Purpose − The purpose of this paper is to propose a new outer-rotor permanent-magnet flux-switching machine for in-wheel electric vehicle propulsion. The paper documents both the design procedure and performance investigation of this novel machine. Design/methodology/approach − The topology and preliminary sizing equations of the outer-rotor permanent-magnet flux-switching machine are introduced. Both the number and width of rotor poles are then optimized using comprehensive two-dimensional FEA. The machine losses are particularly investigated by transient FEA for the optimal design. Findings − A outer-rotor permanent-magnet flux-switching machine, with 12 stator poles and 22 rotor poles, is most suitable for the proposed application. The analytical sizing equations are quite efficient with a suitable level of accuracy for preliminary design. The optimal rotor pole width from the FEA results is nearly 1.3 times of the original one. The efficiency of the proposed machine under rated load is relatively low, nearly 85%, as a result of significant eddy current losses in the permanent magnets, which can be effectively suppressed by implementing segmentation. The predicted outstanding performance implies that by adopting magnet segmentation the proposed machine is a leading contender for direct electric vehicle drives. Research limitations/implications − The end effects, which could be considerable in the machine with relatively short axial length, are neglected during the study. In addition, due to the high current density and deep slot, proximity losses in the winding which is not issued in this research could be significant. All the limitations mentioned above could bring corresponding errors to the results. Although the research is concentrated on the application of electric vehicle drive, the techniques can be potentially employed for other applications. Practical implications − The practical implementation of such a machine is confronted with several mechanical hurdles, especially the thermal issues which can be addressed by implementing innovative cooling system. Originality/value − The outer-rotor permanent-magnet flux-switching machines so far have not been addressed yet. This research provides designers with the technical background and another alternative for electric vehicle propulsion.

Aims: Guided by the biopsychosocial-spiritual model, this study aimed to evaluate the spiritual needs of Chinese women with breast cancer and explored factors associated with those spiritual needs. Design: This study has a cross-sectional design. Methods: This cross-sectional study involved 228 breast cancer patients in China, between May 2019 and July 2019. Data were collected using the general information form, the Spiritual Needs Scale, the Perceived Social Support Scale and the Hospital Anxiety and Depression Scale. Data were analysed by Spearman correlation analysis, univariate analysis and multiple linear regression, and a structural equation model (SEM) was constructed by maximum likelihood estimation.Results: There was a slightly higher average score for spiritual needs. Of the five dimensions of spiritual needs, those with the highest and lowest levels were 'meaning and purpose' and 'relationship with transcendence' respectively. Religion, time since confirmed diagnosis and education level were related to spiritual needs. The proposed model linking spiritual needs perceived social support, anxiety, and depression revealed a satisfactory fit to the data. Specifically, a higher level of social support predicted lower levels of anxiety and depression, which in turn predicted stronger spiritual needs. Conclusions: The spiritual needs of breast cancer patients were associated with individual characteristics and psychosocial elements. Patients' spiritual needs should therefore be effectively evaluated, especially the needs of those who are not religious. Furthermore, comprehensive, needs-tailored interventions that incorporate spiritual, biological, psychological and social support should be formulated. Impact: Nurses should become more aware of the spiritual needs of breast cancer patients, incorporate a spiritual focus into their care and develop comprehensive needs tailored to their characteristics as well as interventions based on biopsychosocial factors.

PurposeThe aim of this paper is to present a new sensorless control strategy using a flux observer, which is particularly designed for taking into account the rotor saliency and winding inductance variation in an interior permanent magnet synchronous motor (IPMSM).Design/methodology/approachIn a PMSM, the magnets‐excited flux‐linkage, i.e. the rotor flux‐linkage, can be expressed as a vector. Its phase angle stands for the rotor position. Therefore, if this vector is estimated with an observer, the rotor position can be obtained without a position sensor, consequently, sensorless control can be realized. The main object of this paper is to establish and implement a model of rotor flux observer, specifically for IPMSM.FindingsThe flux observer model is built on the d‐q‐0 frame, using unequal values of the d‐axis inductance Ld and q‐axis inductance Lq to represent the IPMSM rotor saliency. Its digital implementation is proposed, whilst the sensorless control strategy is experimentally verified.Research limitations/implicationsInsignificant error exists in the estimated rotor position, probably due to the non‐sinusoidal variation of winding inductance. Further improvement of the observer model is preferable.Originality/valueIn previous works, the rotor flux observer is only applied to surface‐mounted permanent magnet synchronous motors (SPMSM) in which the winding inductance is constant. However, the proposed observer can deal with the rotor saliency and inductance variation in IPMSM, whilst its digital implementation is also new.

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