Mary Casey

Martin S Mcnamara

Gerard M Fealy

Ruth Geraghty

Philomena A Halligan

Margaret Treacy

Michelle M Butler

Maree Johnson

Nurses' and Midwives' clinical leadership development needs: A mixed methods study

Keywords: Clinical leaders, leadership development, Needs analysis, Mixed Methods

des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Editor's & Reviewer's Feedback Actions Taken 1. Check the entire paper for grammar. For example, this sentence, The roles of clinical leaders have been specified (Cooke, 2001aand 2001b[START_REF] Davidson | Clinical Leadership in contemporary clinical practice: implications for nursing in Australia[END_REF], and its impact on care outlined, should be revised to read: … and their impact on care (you are referring to roles, not role).

The entire paper has been thoroughly review for grammar.

2. The response rate is exceedingly low, which is a major limitation of the study. Moreover, the usable sample of surveys does not meet the required number, so sample size is not adequately justified. This issue is not yet adequately addressed in the text discussion section.

This section now includes a more complete explanation.

The low response rate to the national postal questionnaire is a limitation of this study. This can be account for in part in the fact that over five hundred returned questionnaires were from nurses and midwives who were ineligible to participate in the study as they were not employed to work in the public health service, a criterion stipulated by the funding body. Furthermore, the use of telephone or e-mail as a complementary method for enhancing the effectiveness of the Dillman method (Axford 1997) was not possible since the sample was anonymous to the researchers. Comparison of the study response rate with that of other large-scale national postal surveys among nurses and midwives in Ireland indicates that the response rates were very similar to those obtained in the Experiences of Empowerment study [START_REF] Scott | Nurses' and Midwives' Understanding and Experiences of Empowerment in Ireland[END_REF], which and reported a response rate 33.1% from a postal survey of 4,000 nurses and midwives and higher than the response of 20% from a survey of 10,000 nurses obtained in the ). A high response rate to questionnaires is considered desirable, particularly if the data are to be used for predictive purposes [START_REF] Meehan | Nursing and Midwifery Research Priorities for Ireland NCNM[END_REF].

The present study sought data on self-reported need and hence the burden of interpretation with reference to predicting need may be considered lower than that demanded in intervention and interrelationship studies. For the present study the response rate achieved must be considered with reference to sampling frame and the context in which the questionnaire was administered. The sampling frame was the Active Register of the Register of Nurses in Ireland, which does not permit targeted sampling of discrete subgroups such as nurses and midwives or those employed in either public or private sectors. In addition, the survey was administered at a time of uncertainty in Ireland when all public servants experienced large reductions in salaries and this mood may have impacted on data collection.

3. Place the ethical considerations section after the survey instrument section and before the data analysis section. . This sentence is unclear or grammatically incorrect: A scale score being an average of the scores on each item with a higher mean value indicated a higher self-reported development need.

This section now reads Scale A measured the perceived importance of each item in the list of items in relation to effective performance of the clinical leader role in practice setting using a five-point scale from 1 ('not important') to 5 ('very important'). Scale B measured respondents' self-perceived clinical leadership development needs in relation to each item on the same list from 1 ('no need') to 5 ('very high 7. The description of the factor analysis continues to read as if separate factor analyses were done for each subsection of the questionnaire. A factor analysis that includes all items will yield a certain number of factors from 1 to x. Each item of the questionnaire loads more or less better on a certain factor. Items are retained on the basis of preset criteria for loading and items that load on more than one factor are typically deleted. Thus, it is unclear why you wrote, for example, that a particular subsection of the questionnaire was made up of two components.

Included in this section is the following explanation

To further define the traits in each scale, factor analysis [START_REF] Johnson | Applied Multivariate Statistical Analyses (5th Edition)[END_REF] was conducted on each scale, and where appropriate new subscales defined. 8. It is unclear why the factor analysis results mention the subsections when the data in Table 4 are only for the 5 subscales that also appear in the left column in Table 2.

Background

Nurses and midwives are expected to fulfill a leadership role at all levels, yet efforts to strategically support them are often unfocused. An analysis of clinical leadership development needs can provide the foundation for leadership initiatives to support staff.

Method

INTRODUCTION

From a global perspective, as providers of front-line clinical care, nurses and midwives are ideally placed to offer clinical leadership that is required to ensure quality and optimum patient care. The roles of clinical leaders have been specified (Cook, 2001aand 2001b[START_REF] Davidson | Clinical Leadership in contemporary clinical practice: implications for nursing in Australia[END_REF], and their impact on care outlined (Dierckx de Casterlé 2008, [START_REF] Hix | Clinical nurse leader impact on microsystems outcomes[END_REF]). However, it is the way that these roles and skills are exercised within these roles that determines leadership effectiveness [START_REF] Gopee | Leadership and Management in Healthcare[END_REF].

BACKGROUND Leadership in nursing and midwifery

Leadership in healthcare involves the creation of conditions for success and the achievement of professional and organizational goals [START_REF] Milward | Clinical leadership in health care: a position statement[END_REF]. In nursing and midwifery, leadership involves taking responsibility for direct care and for monitoring service more generally [START_REF] Davidson | Clinical Leadership in contemporary clinical practice: implications for nursing in Australia[END_REF], Carryer et al. 2007,). Effective leadership empowers individuals and groups to engage in change [START_REF] Casey | Developing a Framework for Partnership between Organizations that provide Nursing and Midwifery Education[END_REF]) and improve quality (Alleyne & Jumma 2007[START_REF] Shaw | [END_REF]. Improving nurses' leadership skills enhances the provision of quality healthcare (Borrill et al. 2002, Large et al. 2005).

The American Association of Colleges of Nursing (AACN) defines a clinical nurse leader as someone who supports and leads innovations that improve outcomes of care, ensures quality and reduces costs, integrates research into practice, is recognised as a leader and an advocate for transforming the health system and implementing best practice [START_REF] Smith | Transforming the care delivery model in preparation for the clinical nurse leader[END_REF]. Clinical leadership enables evidence-based care to improve patient outcomes [START_REF] Milward | Clinical leadership in health care: a position statement[END_REF] [START_REF] Tornabeni | The power of partnership to shape the future of nursing: the evolution of the clinical nurse leader[END_REF]. Hence, clinical leadership is essential in complex health systems, in which multiple professional groups, often with complex interdisciplinary social relationships and at times divergent disciplinary goals, work closely together. The challenge for contemporary leadership in healthcare is to maintain a perspective that combines the lofty goals of strategy formulation with the minutiae associated with the day-to-day management of direct care in the clinical context [START_REF] Casey | Developing a Framework for Partnership between Organizations that provide Nursing and Midwifery Education[END_REF].

Leadership development takes time [START_REF] Hartley | Leadership Development: A Systematic Review of the Literature, NHS Leadership Centre[END_REF] and involves sustained interaction between the clinical leader and coworkers (Dierckx de [START_REF] Dierckx De Casterlé | Impact of clinical leadership development on the clinical leader, nursing team and care-giving process: A case study[END_REF]. Leader development requires human capital, expressed as a range of intrapersonal competences, and social capital which underpins the interpersonal competences required for leadership development as seen in Table 1.

Sample

Survey respondents

The sampling frame was 68,000 nurses and midwives (An Bord Altranais 2008) and with a precision of ± 3% at a 95% confidence interval, it was considered that a sample size of 1,100 would be required. A simple random sample of 3,000 nurses and midwives employed within the Health Service Executive (HSE) in Ireland was selected from the Active file of the Register of Nurses. This ensured that all grades and in each of the five divisions of the Register, viz. general, children's, psychiatric, intellectual disability, and midwife, would be represented. At the closing date for return of questionnaires, a total of 802 (26.73%) replies were received, 534 (17.8%) of which were returned completed and 268 (8.9%) were incomplete. Using the [START_REF] Dillman | Mail and Internet Surveys: The Tailored Design Approach[END_REF] procedure another circulation of R e v i e w C o p y 7 questionnaires were sent to the non-respondents which yielded 630 (27.91%) replies, of which 377 (16.7%) were completed and 253 (11.2%) incomplete. This procedure involves three contacts with the sample: a pre-notification A5 postcard, an initial administration of the questionnaire and a second administration to non-respondents of the first attempt. Accordingly, a total of 1,432 responses were received, of which 521 questionnaires were unusable. From the unusable questionnaires, 477 were categorised as not employed in the public sector (273) or provided no indication of the sector in which employed (194). An additional 29 questionnaires indicated that they were either no longer working in nursing or midwifery, were ill or living abroad. A further 25 questionnaires were returned as undeliverable. This resulted in a valid sample of 2,946 and a useable sample of 911 questionnaires, representing a response rate of 30.92%.

Focus group participants

A purposive sample of all grades of nurses and midwifes from each of the four HSE administrative regions was selected to elicit their view on clinical leadership and their perceived clinical leadership development needs. Twenty-two focus groups were conducted at fourteen different sites which included a mixture of national, regional and local tertiary care centres. The mean number of participants per group was 8 and the range was 3-12 members. Group homogeneity was achieved by grade and discipline in all but one focus group and a total of 184 participants representing all disciplines and clinical and promotional grades participated in the focus groups

Survey instrument

A 'questionnaire' the Clinical Leadership Analysis of Need Questionnaire '(CLAN-Q© ©).' was developed to measure the clinical leadership development needs of nurses and midwives. An initial item pool (Bray et al. 2003) of over one hundred items that reflected critical tasks associated with effective performance as a clinical leader were generated from the literature (Christian and [START_REF] Norman | Clinical Leadership in nursing development units[END_REF], Cook 2001aand 2001b[START_REF] Williams | Literature review: Evidence of the contribution leadership development for professional groups makes in driving their organizations forward Henley Management College[END_REF], Large et al. 2005[START_REF] Davidson | Clinical Leadership in contemporary clinical practice: implications for nursing in Australia[END_REF][START_REF] Dopson | The role of the middle manager in the implementation of evidenced-based health care[END_REF][START_REF] Flood | The Clinical Nurse Manager (2): Unlocking the potential of this Key Role in the Transformation of Irish Health Care[END_REF], Lunn et al. 2008, Sorenson et al. 2008[START_REF] Hix | Clinical nurse leader impact on microsystems outcomes[END_REF]) and critically reviewed by the research team acting as content experts. The items were presented in two Likert scales. Scale A measured the perceived importance of each item in the list of items in relation to effective performance of the clinical leader role in practice setting using a five-point scale from 1 ('not important') to 5 ('very important'). Scale B measured respondents' self-perceived clinical leadership development needs in relation to each item on the same list from 1 ('no need') to 5 ('very high need').

A small pilot study was conducted among a convenience sample of one junior and three senior grades of nurses and midwives in different settings and this provided confirmation of the feasibility of the questionnaire [START_REF] Hallberg | Surveys[END_REF]. Following pilot R e v i e w C o p y 9 testing it was observed that responses to Scale A in all categories elicited responses that were in the higher end of perceived importance (i.e. important and very important). This indicated a threat to the discriminating power of the items with respect to Scale A.

However, given the absence of any extant list of leadership behaviours and capabilities with which to construct a needs analysis scale, the research team considered that it was necessary to retain Scale A as a self-report mechanism of perceived importance as this provided internal validation of each item with respect to Scale B. This consideration outweighed that limitation, and the fact that 80% of the respondents ranked these items as 'very important' lends support for claims of construct validity of the instrument items.

The CLAN-Q incorporated a demographic questionnaire and took approximately twenty minutes to complete.

Validity and reliability of survey instrument

Instrument content validation involved domain identification, item generation, and instrument construction [START_REF] Grant | Selection and use of content experts for instrument development[END_REF]. Each item was independently examined by four experts from the research team and items were excluded or retained on consensus. Finally, a list of 68 items was retained and compiled into three main category scales based on specific concepts based on their fit with emergent constructs, namely 'improving the environment for care delivery' (31 items), 'personal and professional development' (14 items) and 'skills for clinical leadership' (23 items). The multiple iterations of the instrument items and the use of cognitive interviewing principles [START_REF] Drennan | Cognitive interviewing: verbal data in the development and pre-testing of questionnaires[END_REF]) added rigor to the process of content validation. A similar analysis of scale 'personal and professional development' (contained 14 items) also identified two components or subscales; 'development of individual' (9 items) and 'development of the profession' (5 items). Based on scale reliability calculations it was noted that the third subscale relating to 'skills for clinical leadership' improved if one item was deleted. The item 'influencing key stakeholders within the profession' was omitted from the survey, leaving 22 items for this third subscale. The results of factor analysis and the indicative content of the final five subscales are listed in Table 2.

Ethical considerations

Permission for the study was received from the university. Return of the CLAN-Q was accepted as consent to participate in the survey and each participant in the focus group gave informed written consent on the basis of confidentiality. As the distribution of scores are centred near the middle of the range, and are essentially symmetric (skew near 0), the scores were assumed to be normally distributed. Based on repeated measures ANOVA with Greenhouse-Geisser adjustment for non spherical data to correct degrees of freedom, post hoc comparisons of subscales were performed using the Bonferroni method for controlling Type 1 error to 0.05. ANOVA with Tukey's posthoc method was used for comparison between grades on each individual scale.

R

Dependability and credibility of focus groups

The focus group questions were prepared in advance and structured using the same categories that were developed for the national survey instrument, viz. 'the care environment', 'personal and professional development needs', 'professional skills for 13 the free nodes were identified and further explored in the existing and incoming data, a tree node structure was devised. This process allowed relationships between themes to be explored, revealing underlying patterns and relationships in the data, thus assisting dependability. Dependability was also enhanced using a coding framework based largely on the work of [START_REF] Day | Leadership development: A review in context[END_REF]. This framework was modified to refine the tree node structure until the maximum amount of data was accounted for, with minimal overlap and redundancy in order to identify and describe the clinical leadership development needs of nurses and midwives.

RESULTS

The justification for combining quantitative and qualitative methods was to provide a more complete account of clinical leadership development needs and a more detailed explanation of these perceived needs (Bryman 2006). To this end, the results of the survey and focus group are presented separately and 'the mix' is in the interpretative treatment of the results manifest in the unifying discussion (Plano-Clarke and Creswell 2008).

Survey sample characteristics

The majority of the sample was female 92% (n=836) and all promotional grades were represented. The mean age of the sample was 42 years (SD=10.14, range 22-70). Twothirds (66.3%, n=584) worked in a public or public voluntary hospital setting, 21%

Clinical leadership development and promotional grades

For the purpose of analysing differences by grade, nurses and midwives were grouped together and recoded into four categories; 1) staff (incorporating public health nurse), 2) clinical manager, 3) specialist and advanced practitioner and 4)senior manager and director of nursing/midwifery. identify any significant differences. A pooled analysis combining staff and specialists views, based on their greater engagement and proximity to clinical care, with those of middle and senior management levels revealed a significant difference between frontline workers (M=3.12, SD=1.00) and those more distant from the bedside (M=2.89,SD=0.97, p=0.003), where frontline staff expressed a higher leadership development need.

A significant difference between grades in the subscale 'managing patient care' was also observed (F (3,819) =3.41, p=0.017). Pair wise comparison indicated a significant difference between staff (M=2.99, SD=1.14) and manager grades (M=2.67, SD=1.04, p=0.010), with staff reporting higher clinical leadership development need.

No significant differences between grades for the subscale 'development of the individual' (F(3,847)=2.43,p=0.064) was observed. While the scale comparisons indicated that the highest scale across all grades was in relation to' development of the profession', there were no significant differences between grades (F(3,856)=0.36,p=0.781).

There is at least one difference between grades for the 'kills for clinical Just over half the participants in the twenty-two focus groups were employed in general nursing (52%, n=93), a quarter (24%, n= 44) in midwifery and the remainder in either children's nursing (7.7%, n=14), psychiatric nursing (6.6%, n=12) or intellectual disability nursing (4.9%, n=9). The majority (92%, n=169) were female and the average age was 40 years with a range age of 23-60 years.

Clinical leadership and views on clinical leaders

Quality nursing and midwifery services

Participants portrayed a very strong commitment to their role as clinical leaders, patient advocates and protectors of patient dignity and privacy and were uncompromising about the difficulties they encounter in so doing: …you are striving for best practice but the way things are with the patient numbers and the lack of staff it's very hard… to give them a small bit of privacy to see a doctor never mind anything else. (SNG G2)

Roles and functions of clinical leaders

Nurses and midwives emphasised their coordinating role as integrating diverse disciplinary inputs in the interests of patient care; indeed, they regarded themselves as the main group to whom this responsibility fell: …the whole thing is multi-disciplinary…call in this discipline or that discipline but as nurses we're the ones who seem to pull it all together. (CNM G4) Nurses and midwives were seen as ideally placed to provide clinical leadership but this role potential was frequently underutilized and their contributions unrecognized: nurses are uniquely positioned…the difficulty is the level of understanding within other groups may not value that role or may not understand that role …we've been struggling for so many years as a profession, articulating what it is that we bring to the table. ). A high response rate to questionnaires is considered desirable, particularly if the data are to be used for predictive purposes [START_REF] Meehan | Nursing and Midwifery Research Priorities for Ireland NCNM[END_REF].

The present study sought data on self-reported need and hence the burden of interpretation with reference to predicting need may be considered lower than that demanded in intervention and interrelationship studies. For the present study the response rate achieved must be considered with reference to sampling frame and the context in which the questionnaire was administered. The sampling frame was the Active Register of the Register of Nurses in Ireland, which does not permit targeted sampling of discrete subgroups such as nurses and midwives or those employed in either public or private sectors. In addition, the survey was administered at a time of uncertainty in Ireland when all public servants experienced large reductions in salaries and this mood may have impacted on data collection. (Cook 2001a(Cook , 2001b)). While the management of relationships between patients, multidisciplinary team members and the wider organization is widely acknowledged to be a key function of clinical leaders [START_REF] Milward | Clinical leadership in health care: a position statement[END_REF], the ability to articulate concise definitions of clinical leadership and of needs related to its development at the individual, group and wider organizational level varied across the focus groups. It is not surprising therefore that although the subscale' development of the profession', which included items as networking and organizational politics, did not indicate any significant differences between the grades, it was the highest expressed leadership development need. The staff grade expressed higher needs in relation to 'managing the clinical area', 'managing patient care' and 'skills for clinical leadership' and than any manager grade.

Focus group participants spoke of their commitment to motivating other s to improve care and while the acknowledged their responsibility and accountability in providing quality care, they also emphasized their lack of self confidence and autonomy and lack of control over local resources. Clinicians can exert influence in directing patient care by exemplary leadership and by excellence in their practice domain [START_REF] Davidson | Clinical Leadership in contemporary clinical practice: implications for nursing in Australia[END_REF]), but their scope of leadership is influenced by their position, status and the everyday challenges of limited resources. In contrast, managers are somewhat removed from the patient interface but perceive their influence as being greater.

The subscale 'development of the profession' concerning leadership at team, interdepartmental and organizational levels of leadership was the highest reported need among all grades. Focus group data also confirmed that nurses and midwives struggle to get their voices heard at the policy table and feel increasingly excluded within their organizations, which is consistent with the evidence from other Irish studies [START_REF] Tracey | Experiences of top-level nurses Unpublished[END_REF][START_REF] Hogan | A Grounded Theory of the Role of the Directors of Nursing in Band One Teaching Hospitals in Ireland[END_REF], O'Shea 2008). Clinical leadership involves not only taking responsibility for direct care and its outcomes but also for monitoring and developing services in general [START_REF] Davidson | Clinical Leadership in contemporary clinical practice: implications for nursing in Australia[END_REF], Carryer et al. 2007). As the focus shifts away from the bedside and the micro-system in which the nurse or midwife is central [START_REF] Hix | Clinical nurse leader impact on microsystems outcomes[END_REF]) and outwards to the multidisciplinary team and wider organisation, the focus group data suggested that nurses and midwives are much less assured of their roles. Management 2003). This need is linked to their ability to participate fully in multidisciplinary teams, work in partnership and to drive change. When this need is met it gives rise to effective leadership in the way that the leader is aware of the political nuances that impact on clinical practice and can effectively manage conflict and departmental turfism [START_REF] Casey | Partnership: success factors of international relationships[END_REF]. This requires better role differentiation for meaningful integration and highlights the importance of developing both individual leaders and collective leadership [START_REF] Glatter | Of leadership, management and wisdom: A brief synthesis of selected reports and documents on leadership development Prepared for the National College for School Leadership[END_REF] is a difference in the degree of need depending on the promotional grades as highlighted between staff and manager grades. Any strategy for clinical leadership development therefore must take cognisance of the promotional grade and particular context in which nurses and midwives operate as well as the overall development needs of nursing and midwifery as professional disciplines [START_REF] Williams | Literature review: Evidence of the contribution leadership development for professional groups makes in driving their organizations forward Henley Management College[END_REF], Large et al. 2005[START_REF] Tornabeni | The power of partnership to shape the future of nursing: the evolution of the clinical nurse leader[END_REF], Proctor-Thompson 2008[START_REF] Sorensen | Beyond profession: nursing leadership in contemporary healthcare[END_REF][START_REF] Stanley | Congruent leadership: values in action[END_REF].

  Report on the Continuing Professional Development of Staff Nurses and Staff Midwives (National Council for the Professional Development of Nursing and Midwifery

Done 4 .

 4 Citations to the literature used for item generation are needed. Done 5. The survey questionnaire description remains insufficiently clear. What is Scale A and what is Scale B? Done 6

A••

  mixed methods design was used. A questionnaire was sent to 911 nurses and midwives and 22 focus groups comprising 184 participants were conducted. Data were collected between March and June 2009 across all promotional grades of nurses and midwives in Ireland. Repeated measures ANOVA with Greenhouse-Geisser adjustment was used for post-hoc pair wise comparisons of the subscale dimensions of clinical leadership. ANOVA with Tukey's post-hoc method was used for comparison between grades on each individual subscale. Thematic analysis was undertaken on the focus group data. needs related to development of the profession were highest for all grades. The staff grade expressed a higher need in relation to 'managing clinical area', The staff grade of nurses and midwives have higher clinical leadership development needs than managers in relation to managing the clinical area and patient care. • Leadership development need was greater across all grades of nurses and midwives in relation to development of the profession which involves organizational and interdisciplinary interactions with other health care professionals, and influencing clinical decision making and health policy more generally. Clinical leadership in nursing and midwifery is about integrating the clinical leadership role and function into everyday practice to provide a quality service. Implications for Practice and/or Policy • Clinical leadership development must focus on individual and organizational competency development within each individual health care context. • Leadership development initiatives are likely to be more successful if the various dimensions of clinical leadership development need and the promotional grade of the individual are taken into account.• Clinical leadership development initiatives must take a partnership approach between clinical and academic input for the design and delivery of programmes.

  place between March and June 2009. Data for the national postal survey were collected using the Clinical Leadership Analysis of Need Questionnaire (CLAN-Q© ©). Focus group data were collected over the same period. Each focus group was held in private, audio recorded and lasted approximately sixty minutes.

  the traits in each scale, factor analysis[START_REF] Johnson | Applied Multivariate Statistical Analyses (5th Edition)[END_REF] was conducted on each scale, and where appropriate new sub-scales defined. It was determined that the scale 'skills for clinical leadership' consisted a single component.The scale relating to 'improving the environment for care delivery' (31 items) was determined to have two components based on Eigen value greater than 1 from a principal component extraction. Varimax rotation was used to identify which component each item contributed to based on a loading factor greater than 0.5. The two components or subscales were identified as 'managing clinical area' (6 items) and 'managing patient care' (25 items).

  undertaken using the Statistical Package for the Social Sciences© (SPSS Version 15.0) software. Descriptive variables related to respondents' demographic characteristics were summarised using frequency distributions to describe the sample.

  leadership'. Dependability was enhanced by the use of a topic guide[START_REF] Holloway | Research in Nursing 2 nd[END_REF], based on the three categories as the questionnaire and by judicious group moderation and by analysis of the data by two members of the research team which achieved complete agreement on the interpretation and analysis of themes. Data analysis involved data reduction, exploration and synthesis (Attride-Stirling 2001). Credibility of the analysis was enhanced by adherence to systematic analytical process which involved reading each transcript closely and breaking down significant segments into themes which were allocated to free nodes using NVivo 7© ©. As significant relationships between

  among promotional grades was observed in the subscale 'managing the clinical area' (F (3,865) =2.906, p=0.034). Pair wise post hoc tests did not

  leadership' (F (3,819) =3.232, p=0.022). Post-hoc comparisons identified that staff grade (M=3.14, 1.031) differed from manager grade (M=2.85, SD=.94, p=0.011), with staff expressing a higher clinical leadership development need.

  Focus group participants found it difficult to agree on a definition of clinical leadership, but agreed that it is founded on clinical expertise, experience and credibility. Being a clinical leader was seen as more challenging for clinical nurse managers and midwifery managers (CNM/CMM) due to their position in the organization (middle management) their multiple and conflicting responsibilities and poor role definition:We describe ourselves as the meat in the sandwich…we are like the filling. Stuck in the middle…we are the ones that are being pushed from the top down…. (CNMG1) Clinical leaders were seen as the 'guardians' of patient care and expected to advance nursing and midwifery practice by advocating for patients' interests and by maintaining standards: I think at the core of it is patient advocacy, patient-centred care…emphasis is on quality and safety … maintenance of standards is at the core of what we're at.(DoN&M)

  (DoN & M) All grades were able to provide examples of specific initiatives that had made a difference to patient care. Directors, specialists and some managers emphasised the importance of challenging existing practices and initiating change at organizational level.Discussions around dealing with conflict arose mainly in response to concerns about Where these result from the actions or omissions of nursing or midwifery colleagues, participants indicated that they would try to deal with concerns at the lowest appropriate level and refer upwards according to their professional judgment and established policies: the best way is to talk to the person privately…in a safe, professional way…I think being honest and professional is the right way to approach a colleague …it depends how serious it was…you try and solve it as local as possible. (SNGG4)Dealing with concerns about medical colleagues was considered much more of a challenge: the majority of your battles when it comes to patients, and they are right social implications. (CNMG1)resources and competencies for clinical leaders and leadershipA lack of personal and professional autonomy was a recurring theme in the data: 'we' can literally do absolutely nothing because 'we' don't have power …to do anything….there is a lack of support there…there's no support. (CMMG1) Participants indicated a leadership development need at the interpersonal level associated with intrapersonal needs expressed through feelings of powerlessness and poor self and professional image:we're looked down on ... if you're down in the pecking order you end up hitting a brick wall…they don't listen to us. (SNID) There were numerous examples of nurses' and midwives' motivation, personal initiative and commitment to initiating change and while there was consensus that managing vital ingredient of clinical leadership, participants believed that their initiative was not effectively harnessed. This again suggested a leadership need at the wider organizational level: one of the big problems in changing policy …they don't have the time…ward meetings are going out the window…there's nowhere to come together and say, how do we feel things are going, how can we improve? (SMG1)The context of clinical leadershipWhether leaders' human capital, as manifest in their intrapersonal competences, translates into social capital and effective leadership depends on the context in which they operate. Overall, motivation, recognition of contribution, teamwork, mutual respect, organizational support and inclusiveness were identified as the key ingredients of a supportive work context: from the time a staff nurse comes to work in a unit… there's a development plan put in place…the hospital is very proactive in allowing staff to participate in these programmes. (CNM G5) DISCUSSION Study limitations Leadership is culturally influenced and context-dependent, hence the outcomes of this study are most relevant to how nursing and midwifery is delivered in Ireland, and regulatory frameworks and clinical environments in other countries may elicit different leadership development needs.The low response rate to the national postal questionnaire is a limitation of this study. This can be account for in part in the fact that over five hundred returned questionnaires were from nurses and midwives who were ineligible to participate in the were not employed to work in the public health service, a criterion stipulated by the funding body. Furthermore, the use of telephone or e-mail as a complementary method for enhancing the effectiveness of the Dillman method (Axford 1997) was not possible since the sample was anonymous to the researchers. Comparison of the study response rate with that of other large-scale national postal surveys among nurses and midwives in Ireland indicates that the response rates were very similar to those obtained in the Experiences of Empowerment study[START_REF] Scott | Nurses' and Midwives' Understanding and Experiences of Empowerment in Ireland[END_REF], which and reported a response rate 33.1% from a postal survey of 4,000 nurses and midwives and higher than the response of 20% from a survey of 10,000 nurses obtained in the Report on the Continuing Professional Development of Staff Nurses and Staff Midwives (National Council for the Professional Development of Nursing and Midwifery (NCNM) 2004

  that clinical leadership is directed at ensuring quality patient services, and nurses and midwives closest to the patient consider themselves wellpositioned to make a difference to patient and quality care. The staff grade expressed higher development needs in relation to 'managing the clinical area', 'managing patient care' and 'skills for clinical leadership' which involved activities such as coordinating care, developing effective working relationships with the interdisciplinary team, managing conflict, implementing change, coordinating care and ensuring adequate resources for care. The principal mechanisms through which nurses and midwives impacted on patient care were patient advocacy and safety, maintaining dignity and privacy through the co-ordination of the care. These mechanisms are well supported in the literature where a clinical leader is an expert clinician involved in providing direct clinical care and as a clinician can influence others to achieve optimal care

  these needs is warranted to determine what role the organisation and individual can contribute to meeting this leadership development need deficit. Whether and to what extent nurses and midwives gain recognition and exert influence at the individual, team, department and organizational levels will ultimately impact on the quality of patient services. The need for nurses and midwives to be involved at strategic and operational levels of decision-making is essential to the development of more accountable and integrated health services (O'Shea 2008). That nurses and midwives in management positions should be so constrained in acting as leaders removes a source of role models and mentors for junior colleagues and an incentive to assume such roles. Hence, a distinct leadership development need for nurses and midwives is the ability to better represent their unique contributions to patient outcomes in a credible manner. Clinical leaders in nursing and midwifery advocate for patients and for their professions (NCNM 2005) and shared decision-making among doctors, nurses and other health professionals is an important condition for such wider advocacy (Office for Health

  thereby building individual and organizational capacity. These competences require capacity-building through as communication and decision making, advocacy, empowerment, quality, partnership, and political awareness. This finding supports leadership development approaches that address the intrapersonal, such as self awareness and the interpersonal domains of competence associated with the individual, team, departmental and organizational levels (McAuliffe et al. 2002, Large et al. 2005, Sorensen et al. 2008, Stanley 2008, Tornabeni & Miller 2008) Clinical leadership development Needs in relation to the dimensions of clinical leadership development were successfully identified using the ©CLAN-Q. These needs are related to managing clinical area, managing patient care, development of the individual, development of the profession and skills for clinical leadership. On the evidence in this study leader development, in terms of self awareness, and leadership development (collective organizational context) must be considered as part of the spectrum of clinical leadership development. Moreover, there

  competency development must be key outcomes of clinical leadership development initiatives for nursing and midwifery. This requires a focus on the individual, the professions and the organizations in which they operate. Undertaking clinical leadership needs assessment and developing mechanisms to address leadership deficits at individual, team, department and organisational levels are necessary. Clinical leadership development is a shared responsibility and those in leadership positions must work together across professional boundaries to secure the recognition and influence that they need so that clinical leadership capacity can be harnessed, developed and deployed in the interests of patient care. (1997) Enhancing Dillman's total design method for mailed/ telephone surveys using current technology to maximise cost-benefit ratios Journal of Sociology 33(3), 387-393. Bourdieu P. (1997) The forms of capital. In Education, Culture, Economy, Society (Halsey A.H.L., Brown P. & Wells A.S., eds), Oxford University Press, Oxford. Borrill C., West M., Dawson J., Shapiro D., Rees A., Richards A., Garrod S., Carletta J. & Carter A. (2002) Team Effectiveness in Health Care: Findings from the Health Care Team Effectiveness Project. Report from Aston Centre for Health Service Organization Research, Aston University. Bray C.O., Nash K. & Fromanz R.D. (2003) Validation of measures of middle schoolers' self efficacy for physical and emotional health, and academic tasks. Research in Nursing and Health 26, 376-386. Bryman A. (2006) Integrating quantitative and qualitative research: How is it done? Qualitative Research 6(1), 97-113. Carryer J., Gardner G., Dunn S. & Gardner A. (2007) The core role of the nurse practitioner: practice, professionalism and clinical leadership. Journal of Clinical Nursing 16the Professional Development of Nursing & Midwifery (2004) Report on the Continuing Professional Development of Staff Nurses and Staff Midwives NCNM, Dublin. National Council for the Professional Development of Nursing and Midwifery (2005) A Preliminary Evaluation of the Role of the Advanced Nurse Practitioner NCNM, Dublin. National Health Service Scotland (2004) Leadership Development Framework for Discussion NHS Scotland. Office of Health Management (2003) Clinicians in Management: A Review of Clinical Leadership -Discussion Paper 4 Office of Health Management, Dublin. O'Shea Y. (2008) Nursing & Midwifery in Ireland: A Strategy for Professional Development in a Changing health Service, Blackhall Publishing, Dublin. Plano-Clark V. and Creswell J. (2008) The Mixed Methods Reader Sage Publications Ltd, London. Proctor-Thomson S.B. (2008) Constellations or stars? What is being developed in leadership development? Lancaster University Management School, Centre for Excellence in Leadership (CEL).

Table 2

 2 provides details of the results of factor analysis in terms of subscale titles and indicative content.

Table 4

 4

	indicates the dimensions of
	clinical leadership in terms of mean,
	standard deviation and skewness

1 Nurses'

and Midwives' clinical leadership development needs: A mixed methods study

	Aim
	This paper is a report of a descriptive study of nurses' and midwives' clinical leadership
	development needs.

Table 1 Key Aspects of leader and leadership development (Day 2001) Aspects of leader development (Human Capital) Aspects of leadership development (Social Capital)

	expressed, in the interpersonal domain, in the leadership roles and processes (McCauley
	et al. 1998).
	THE STUDY
	Aim
	The aim of this study was to describe nurses' and midwives' clinical leadership
	development needs.
	Design A concurrent triangulation mixed methods design involving a survey and focus group R e v w e i interviews was used.
	Building intrapersonal competence Developing individual knowledge, skills and abilities	Building interpersonal competence Building network relationships through C o p
	interpersonal exchange Self awareness (emotional awareness, self confidence) Social awareness (empathy, service orientation y
			and enabling others)
	Self regulation (self control, trustworthiness, ability to	Social skills (collaboration, partnership,
	cope with change)		cooperation, conflict management)
	Self motivation (commitment, take initiative, positive	Membership of influential social networks
	outlook)		(Bourdieu 1997, Maton 2005)
	Both leader and leadership competency development must be addressed for the
	integration of the cognitive, affective and behavioural dimensions of the role required to
	enact leadership. Essentially, leadership development involves building individual and
	organizational capacity so that members' intrapersonal competences can be effectively
	6

Table 2 Results of factor analysis, subscale titles and indicative content of CLAN-Q instrument Subscales, factor analysis, number of items of category scale 'improving the environment for care delivery'

 2

	Subscale Title	Number of items and indicative content of subscale
	Managing clinical area	Contained 6 items related to coordinating care in the work setting, ensuring
	Eigenvalue 20.53	adequate resources to provide optimum care, identifying priorities for
	% of Variance 66.24	service improvement, and ensuring that team members carry out duties
	Cumulative % 66.24	appropriate to their grade.
	Managing patient care	Contained 25 items related to protecting dignity and confidentiality of
	Eigenvalue 1.34	patients, involving patients in their own care, contributing to the

Subscales, factor analysis, number of items of category scale 'personal and professional development

	Development of individual	Contained 9 items related to demonstrating commitment to lifelong learning,
	Eigenvalue 8.53	recognising own strengths and weaknesses, coping effectively with pressure,
	% of Variance 60.93	and acting as a mentor to colleagues
	Cumulative % 60.93
	Development of profession	Contained 5 items related to participating in nursing/midwifery forums,
	Eigenvalue 1.63	networking and understanding the impact of organisational politics on the
	% of Variance 11.61	work of the profession.
	Cumulative % 72.54
	Subscales,

factor analysis, number of items of category scale 'skills for clinical leadership'

  Skills for clinical leadership Contained 22 items related to effective working relationships with the interdisciplinary team, motivating others, accepting accountability, and initiating change to ensure optimal care

The reliability of each subscale was examined by calculating a Cronbach's Alpha coefficient. An acceptable Alpha level is 0.7 or above, and the properties of the five scales were: 'managing clinical area' contained 6 items, α=0.91, 'managing patient care' contained 25 items, α=0.98; 'development of individual' contained 9 items, α=0.96; 'development of profession' contained 5 items α=0.91 and 'skills for clinical leadership' contained 22 items, α=0.98.

  n=180) worked in the community or in nursing homes and other non acute care sector.

	midwives accounted for just over 5% (n=46). Details of the grades of each participant are
	provided in Table 3.
	R e v i e w
	C o p
	y
	The majority of respondents (61.5% (n=547) were employed as general nurses and
	14

Table 3 . Survey results in relation to grade at which currently employed

 3

		Percentage
	Grade	(number)
	Staff Nurse	66.6 (n=599)
	Clinical Nurse Manager level 1 (CNM1)	6.3 (n=57)
	Clinical Nurse Manager level 2 (CNM2)	10.6 (n=95)
	Clinical Nurse Manager level 3 (CNM3)	1.1 (n=10)
	Clinical Nurse Specialist	5.1 (n=46)
	Advanced Nurse Practitioner	0.4 (n=4)
	Assistant Director of Nursing	3.1 (n=28)
	Director of Nursing	0.8 (n=7)
	Staff Midwife	3.9 (n=35)
	Clinical Midwife Manager level 1 (CMM1)	0.2 (n=2)
	Clinical Midwife Manager level 2 (CMM2)	0.8 (n=7)
	Clinical Midwife Manager level 3 (CMM3)	0.4 (n=4)
	Clinical Midwife Specialist	0.2 (n=2)
	Advanced Midwife Practitioner	0.1 (n=1)
	Assistant Director of Midwifery	0.2 (n=2)
	Director of Midwifery	0 (n=0)
	Missing	1.3 (n=12)
	Total	100 (n=911)
	The sample was representative when compared with the national Register of Nurses
	statistics of just under 92,000 qualifications. In the study sample of registrations of 1,306,
	general nursing was underrepresented 58% (n=755) compared to 63% (n=57,474) in the
	national Register. Psychiatric Nursing was (9% n=112) approximately 2.1% less
	representative than the national Register (11% n=9796) and there was slight over
	representation of midwifery of 17% (n=222) compared to 14% (n=12,988) and,
	intellectual disability accounted for 7% (n=86) compared to 5% (n=4,233) and public
	health over representative at 4% (n=47) than the national Register of 3% (n= 2,378).

(M=3.04, SD=1.00, p<0.001). The five subscales of dimensions of clinical leadership development need are presented in Table

4

.

Table 4 Subscales of clinical leadership development need Subscale of Clinical Leadership Development Need

 4

		Mean	SD	Skewness n	Missing
						values*
	Managing the clinical area	3.07	1.0	0.19	880	31
	Managing patient care	2.92	1.1	0.31	834	77
	Development of individual	3.04	1.0	0.24	863	48
	Development of profession	3.22	0.99	0.05	872	39
	Skills for clinical leadership	3.07	1.0	0.15	834	77
	*Non responses

Journal of Advanced Nursing


F Benchabane
email: fateh_benchabane@yahoo.fr.

A Titaouine

O Bennis

K Yahia
email: kd_yahia@yahoo.fr.

D Taibi

Systematic Fuzzy Sliding Mode Approach Combined With Extented Kalman Filter for Permanent Magnet Synchronous Motor control

Keywords: permanent magnet synchronous motor, extended Kalman filter, sensorless control, load torque observation, initial position, fuzzy, systematic sliding mode

This paper proposes a new state observer based on an extended Kalman filter (EKF) for the sensorless systematic fuzzy sliding mode control of permanent magnet synchronous motors (PMSM). The observer can obtain a precise estimation of rotor speed and position. Load torque is also observed and used as the feed-forward compensation to improve the system performance during load torque changes. In this system, the initial rotor position is not necessary for the start up.

I. INTRODUCTION

Permanent magnet synchronous motors (PMSM) are more and more used because of their good performances. High performance control of the PMSM requires identification of the rotor position which is usually measured by a mechanical rotor position sensor, which increases the cost and the instability of the system. As a result, sensorless control has recently become a research focus [1,2].

In this study, a fuzzy sliding-mode control system, which combines the merits of the sliding-mode control, the fuzzy inference mechanism and its algorithm, is proposed. In the sliding-mode controller a switching surface that includes an integral operation [3,4] is designed. When the sliding mode occurs, the system dynamic behaves as a robust state feedback control system. Furthermore, in the general sliding-mode control, the upper boundary of uncertainty, which include parameter variations and external load disturbance, must be available. However, the boundary of uncertainty is difficult to determine in advance for practical applications. A fuzzy sliding-mode controller is investigated to resolve this difficulty, in which a simple fuzzy inference mechanism is used to estimate the upper boundary of uncertainty. Furthermore, to reduce the control effort of the sliding-mode controller, the fuzzy inference mechanism is improved by adapting the centres of the membership functions to estimate the optimal boundary of uncertainty [5][6][7].

In this paper, a new state observer based on an extended Kalman filter is proposed. The precis rotor position and speed can be obtained by EKF. Then a sensorless speed control system can be formed. The load torque is used as the feedforward compensation of the reference torque at the output of the speed regulator. With the compensation, the speed fluctuations during load torque impacts can be greatly decreased.

II. PMSM MODEL

With the simplifying assumptions relating to the PMSM, the model of the motor expressed in the Park reference frame is given in the suitable state form [8,9]:

X F(X) G U Y H(X) ⎧ = + ⋅ ⎨ = ⎩ & (1)
where:

1 1 1 d 3 2 2 x y (X) h (X) I Y(X) x y (X) h (X) ⎡ ⎤ ⎡ ⎤ ⎡ ⎤ ⎡ ⎤ = = = = ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ Ω ⎣ ⎦ ⎣ ⎦ ⎣ ⎦ ⎣ ⎦ d d 1 d 2 q q q 3 1 0 L I x V 1 X x I ;U ;G 0 V L x 0 0 ⎡ ⎤ ⎢ ⎥ ⎢ ⎥ ⎡ ⎤ ⎡ ⎤ ⎡ ⎤ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ = = = = ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ ⎣ ⎦ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ Ω ⎣ ⎦ ⎣ ⎦ ⎢ ⎥ ⎢ ⎥ ⎣ ⎦ 1 1 2 2 3 1 2 1 2 2 1 3 3 3 3 l 1 3 2 1 2 3 2 a x a x x f (X) F(X) f (X) b x b x x b x f (X) T c x c x x c x J ⎡ ⎤ ⎢ ⎥ ⋅ + ⋅ ⋅ ⎡ ⎤ ⎢ ⎥ ⎢ ⎥ = = ⋅ + ⋅ ⋅ + ⋅ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ ⎣ ⎦ ⎢ ⎥ ⋅ + ⋅ ⋅ + - ⎣ ⎦ and: q s s d 1 2 1 2 d d q q d q f f 3 1 2 3 q p L R R p L a ; a ; b ; b L L L L p (L L ) p p f b ; c ; c ; c L J J J ⋅ ⋅ = - = = - = - ⋅ - ⋅ φ ⋅ φ = - = - = =
in 1 f (X) the load torque l T is removed from the state equations and will be considered as a perturbation.

III. SPACE VECTOR MODULATION (SVM)

In space vector modulation techniques, the reference voltages are given by space voltage vector and the output voltages of the inverter are considered as space vectors. There are eight possible output voltage vectors, six active vectors u1-u6, and two zero vectors u0, u7 (Figure . 1). The reference voltage vector is realized by the sequential switching of active and zero vectors. Figure 1 shows reference voltage vector uref and eight voltage vectors, which correspond to the possible states of inverter. The six active vectors divide a plane for the six sectors 1-6. In each sector, the reference voltage vector uref is obtained by switching on, two adjacent vectors for an appropriate duration. As seen in in figure 1 The six active tension vectors can be formulated by: ( )

j i 1 3 i dc 2 u u , i=1, 2, 3, 4, 5, 6. 3 π - = e (2)
Where: udc is a dc voltage.

Figure. 2. Projection of the reference vector (sector 1)

Figure 2 shows the case when the reference vector is in sector 1. The times T1 and T2 are obtained by simple trigonometrical relationships and can be expressed in the following equations:

1 2 0 1 2 ref 1 2 T T T T T T u u u T T = + + ⎧ ⎪ ⎨ = + ⎪ ⎩ (3) and:
( )

( ) 2 2 s ref 1 1 s ref s ref T u u c o s3 0 T T u u x T u x tg 60 β α β ⎧ ⎪ = ⎪ ⎪ ⎪ = + ⎨ ⎪ ⎪ = ⎪ ⎪ ⎩ o o (4)
Finally, according to (2), the application periods of every vector is given by: ( )

1 s ref s ref dc 2 s r e f dc T T 6 u 2 u 2u T T 2 u u α β β ⎧ = - ⎪ ⎪ ⎨ ⎪ = ⎪ ⎩ (5)

IV. SLIDING MODE CONTROLLER DESIGN

The advantages of the sliding mode controller can be summarized as follows [5,11]:

1) Fast response with no overshoot.

2) No steady state error.

3) Robustness, stability in a closed loop environment, insensitivity to parameter variations and load disturbances. The switching patterns for a six-pulse inverter are generated directly by the sliding mode. The SMC is designed in d -q plane, and the voltages d q V ,V * * , are taken as control inputs.

The following switching hypersurfaces are used: The control inputs are taken as follows:

d d 1 V K sign(S ) * = (8) q q 2 V K sign(S ) * = (9)
the gains d K , q K are selected so as to satisfy the existence condition of the sliding mode:

i . i i S 0 lim S S 0,i 1, 2 → < = ( 10
)
Which is equivalent, using the Lyapunov stability, to

2 i i 1 V V = = ∑ (11) with 2 i i 1 V S 2 = (12)
Then, for the control system to be stable, the time derivative of (11) must be negative, i.e. Only the information about the boundaries of q I and is needed before designing the SMC. Here NB is negative big, NM is negative medium, ZR is zero, PM is positive medium and PB is positive big, are labels of fuzzy sets and their corresponding membership functions are depicted in figures 4, 5 and 6, respectively. The continuity of input membership functions, reasoning method, and defuzzification method for the continuity of the mapping u fuzzy (e, e) ⋅ is necessary. In this paper, the triangular membership function, the max-min reasoning method, and the center of gravity defuzzification method are used, as those methods are most frequently used frequently in the literature [4,13].

VI. DESIGN OF EKF OBSERVER

Accurate and robust estimation of motor variables which are not measured is crucial for high performance sensorless drives. A multitude of observers have been proposed, but only a few are able to sustain persistent and accurate wide speed range sensorless operation. At very low speed, theirs performances are poor. One of the reasons is the high sensitivity of the observers to unmodeled nonlinearities, disturbance and model parameters detuning.

The Kalman filter provides a solution that directly cares for the effects of disturbance noises including system and measurement noises. The errors in parameters will also normally be handled as noise [14].

The dynamic state model for non non-linear stochastic machine is as follows where all symbols in the formulations denote matrices or vectors [12,14]:

x(t) f (x(t), u(t), t) w(t) y(t) h(x(t), t) v(t) • ⎧ ⎪ = + ⎨ ⎪ = + ⎩ (18)
w(t) : System noise vector. v(t) : Measurement noise vector w, v : are unrelated and zero mean stochastic processes.

A recursive algorithm is presented for the discrete time case. For the given sampling time s T , both the optimal estimate sequence k / k x and its covariance matrix k / k P generated by the filter go through a two step loop.

The first step (prediction) performs a prediction of both quantities based on the previous estimates k 1/ k 1

x --and the mean voltage vector actually applied to the system in the period from k 1 T -to k T .F is the system gradient matrix (Jacobean matrix).

T x(t) x(t) f (x(t), u(t), t) F(x(t), t) x (t) = ∂ = ∂ % % (19) k/k 1 k 1/k 1 s k 1/k 1 k 1 x x T. f(x ,u ) - - - - - - = + (20) T k/k 1 k/k 1 k 1/k 1 k 1/k 1 s P P (F P P F ) . T Q - - - - - - = + + + (21)
The second step (innovation) corrects the predicted state estimate and its covariance matrix trough a feedback correction scheme that makes use of the actual measured quantities; this is realized by the following recursive relations:

k / k k / k 1 k k k / k 1 x x K (Y Hx ) - - = + - (22)
k / k k / k 1 k k / k 1 P P K HP - - = - (23)
Where the filter gain matrix is defined by:

T T 1 k k / k 1 k / k 1 k P H (HP H R) - - - = + (24) H is transformation matrix. x(t) x(t) h H(x(t), t) x = ∂ = ∂ % % (25)
The proposed EKF observer is designed in rotor reference frame ( d,q frame).

The state vector is chosen to be:

T d q X [I I ] = Ω θ Input: T d q U [V V ] = ; Output: d q Y [I I ] = d q
I ,I and d q V ,V are motor stator currents, voltages in rotor reference frame. The noise covariance Q reflects the system model inaccuracy, the errors of the parameters and the noise introduced by the voltage estimation [3,17]. Q has to be increased at stronger noise driving the system, entailing a more heavily weighting of the measured current and a faster transient performance.

An initial matrix 0 P represents the matrix of the covariance in knowledge of the initial condition. Varying 0 P affects neither the transient performance nor the steady state condition of the system. In this study, the value of these elements is tuned "manually", by running several simulations. This is may be one of the major drawbacks of the Kalman filter.

The blocks CNL, SMC are regulators, the first is the nonlinear controller for speed, and the second is the sliding mode control regulator for rectifier.

Figure 5 shows the proposed Sensorless nonlinear control using EKF. In this study, the outputs of a PWM voltage source inverter are used as the control inputs for the EKF. These signals contain components at high frequencies, which are used as the required noise by the Kalman filter. Thus, no additional external signals are then needed.

T d q q s s d s q s d d d d d s s f s d s q s s q q q q q d q sf s q d s q s s l f (x(k), u(k)) I I L R 1 (1 T )I p T I T V L L L L R 1 ( p T )I (1 T )I T p T V L L L L L L f 1 pT I I pT I (1 T ) T T J J J J ⎡ ⎤ = Ω θ = ⎣ ⎦ ⎡ ⎤ - + Ω + ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ φ -Ω + - - Ω + ⎢ ⎥ ⎢ ⎥ ⎢ ⎥ - φ ⎢ ⎥ + + - Ω - ⎢ ⎥ ⎢ ⎥ Ω ⎣ ⎦ (26)
where:

T d q h I I ⎡ ⎤ = ⎣ ⎦ Figure.
8. Speed control of a PMSM using the Fuzzy Sliding mode with an EKF for speed and position estimation.

VII. LOAD TORQUE ESTIMATION

The load torque is not easily measurable so it has to be estimated. The method suggested by Le Pioufle allows estimating it in real-time [8]. Figure 9 illustrates the principle for estimation. The error between measured speed and estimated speed is presented like the entry of the PI regulator: Figure 11 shows the responses of speed, position, currents I d and I q load torque with errors between the actual and estimated states for step reference with 75% of rated load at t=0.1 s. At t=0.2 s the speed is reversed from +100rad/s to -100rad/s and at t=0.4 s the reference speed becomes 10 rad/s. These responses illustrate high performances of the proposed EKF observer combined with Fuzzy Sliding mode during transient and steady states and the EKF works at very low speed, where many speed estimators or observers perform poorly.

  the reference vector uref can be implemented by the switching vectors of u1, u2 and zero vectors u0, u7 [10].

Figure. 1 .

 1 Figure. 1. Principle of space vector modulation.

  These selections are based on the concept of vector control and instantaneous current control[5,11,12]. and are related to inner loop (current loop). In this case, the current components d I and q I are decoupled. The reference currents dref I and qref I are determined by the outer loop.

  of a complete fuzzy control system is given in figure 3. The plant control u is inferred from the two state variables, error (e) and change in error ∆e [4]. The actual crisp inputs are approximates of the closer values of the respective universes of discourse. Hence, the fuzzyfied inputs are described by singleton fuzzy sets.The design of this controller is based on the phase plan. The control rules are designed to assign a fuzzy set of the control input for each combination of fuzzy sets of and[5,13]. Table1 showsone of possible control rule base. The rows represent the rate of the error change e ⋅ and the columns represent the error (e) . Each pair (e, e) ⋅ determines the output level NB to PB corresponding to u .

Figure. 3 .

 3 Figure. 3. The structure of a fuzzy logic controller.

Figure. 4 .Figure

 4 Figure. 4. Membership functions for input e

Figure. 7

 7 Figure. 7. S-Function representation of the EKF.

Figure. 9 .

 9 Figure. 9. Estimation of load torque.

  by poles imposition .

Figure. 10 .

 10 Figure. 10. Estimation of load torque VIII. SIMULATION RESULTS Extensive simulations have been performed using Matlab/ Simulink Software to examine the control algorithm of the

Figure. 11

 11 Figure.11 Drive response under reference speed inversion under load disturbances

Table .

 .

	1. Rules Base for speed control

IX. CONCLUSION

In this paper, the authors determine fuzzy sliding mode control of a permanent magnet synchronous motor. The dynamic behavior and the control performances obtained are satisfactory. The perturbation is rejected.

The observer based on an extended Kalman filter can observe the exact rotor speed and position. The EKF observer is able to increase the performance of the fuzzy sliding mode control in terms of low-speed behavior, speed reversion and load rejection.