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A hybrid formulation is proposed that incorporates finite element substructuring and Galerkin boundary elements in the numerical solution of Poisson's or Laplace's equation with open boundaries. Substructuring the problem can dramatically decreases the size of matrix to be solved. It is shown that the boundary integration that results from application of Green's first theorem to the weighted residual statement can be used to advantage by imposing potential and flux continuity through the contour which separates the interior and exterior regions. In fact, the boundary integration is of exactly the same form as that found in Galerkin boundary elements.

This paper aims to establish a piecewise Maxwell stress analytical model of bearingless switched reluctance motor (BSRM) for the full rotor angular positions. The proposed model varies from the existing models, which are only applicable to the partial-overlapping positions of stator and rotor poles. By extending the applicable rotor angular positions, this model provides a basic analytical model for the multi-phase excitation control of BSRM.

The full rotor angular positions are classified into the partial-overlapping positions and the non-overlapping positions. At first, two different air gap subdividing methods are proposed, respectively, for the two-position ranges. Then, different integration paths are selected accordingly. Furthermore, two approximate methods are presented to calculate the average flux density of each air gap subdivision. Finally, considering the mutual coupling between the two perpendicular radial suspension forces, a piecewise Maxwell stress analytical model is derived for the full rotor angular positions of BSRM.

A piecewise Maxwell stress analytical model of BSRM is built for the full rotor angular positions, and applicable to the multi-phase excitation mode of BSRM. For the partial-overlapping positions and the non-overlapping positions, two sets of air gap subdividing methods, integration paths and approximate calculation methods of air gap flux densities are proposed, respectively. The accuracy and reliability of the proposed model are verified by the finite element method.

The piecewise Maxwell stress analytical model of BSRM for the full rotor angular positions is proposed for the first time. The novel air gap subdividing methods, integration paths, approximate calculation methods of air gap flux densities and the coupling between the two radial suspension forces are adopted to improve the modeling accuracy. As the applicable range of rotor angular position is extended, this model overcomes the limitation of the existing models only for single-phase excitation mode and contributes to the accurate control of BSRM multi-phase excitation mode.

This paper deals with closed‐loop control of a switched reluctance generator (SRG).

The control objective when generating is to maintain the dc link voltage at the required value while achieving maximum efficiency. Three possible control schemes are presented and their performance is examined by testing on an experimental 12/8 three‐phase SRG.

A very simple control scheme that requires no prior characterisation of the SRG, an approach based on the use of an inverse machine model and finally, a control scheme that is aimed at achieving optimal efficiency are described and experimental results for all three are presented.

The inverse machine model control scheme and the optimal efficiency control scheme require operation at a constant voltage reference for accurate operation (although this is the case for many generator applications). Possible future research might include the expansion of these control schemes to operation with a variable voltage reference.

The importance of maximising efficiency is emphasised with a clear method of deriving the optimal efficiency firing angles described.

This paper provides a good overview of SRG operation through the experimental implementation of three separate closed‐loop voltage control schemes, each of which is described in detail.

This paper aims to propose an effective method to verify poles polarities of switched reluctance motors (SRMs). Different from the ways of detection poles polarities by permanent magnet in SRMs, the difference of self-inductance between different winding connections is used to verify the pole polarity.

First, the winding connections with the forward and reverse series are proposed. The magnetic circuit models are established to analyze the flux linkage of different winding connections. Then, according to the difference of inductance characteristics, including the self-inductance and the mutual inductance affected by the adjacent poles, it is theoretically feasible to verify the polarity of each pole. Finally, the proposed method is verified by the simulation and experiment on a six-phase SRM.

First, compared to the reverse series, the forward series can produce larger self-inductance when one phase is excited at the same current excitation, which can be used to verify the poles polarities of one phase with different winding connection. Second, the mutual inductance can be used to distinguish the winding connections. Third, the difference of the maximum self-inductance of the winding, which is composed of two adjacent windings, can be used to verify the polarities of the adjacent poles.

This paper proposes an effective method to verify poles polarities of SRMs.

Because of the shortage of energy, the development of green and reliable energy is particularly important. As a green and clean energy, wind power is widely used. As the core component of wind power generation, it is particularly important to choose generators with high reliability. Switched reluctance machine is widely used as generators because of its strong fault tolerance and high reliability. Therefore, this paper aims to propose a power converter and its control strategy to improve the efficiency of switched reluctance generators.

In this paper, a full-bridge power converter (FBPC) instead of the asymmetric half-bridge power converter (AHBPC) is adopted to drive the switched reluctance generator (SRG) system. Compare the FBPC with the AHBPC, the FBPC has several advantages including low cost and modularization, and operation process of SRG winding current direction is variable.

The results show that the SRG system can keep smooth operation by the FBPC with relatively high efficiency.

The FBPC is suitable to drive the SRG system. Meanwhile, this paper introduces two excitation modes of the FBPC as three-phase three-beat mode and six-phase six-beat mode. When the six-phase six-beat control strategy is adopted, the dead band time of the converter can be avoided. At the same time, the SRG has higher efficiency.

To investigate the use of amorphous iron as the stator core material to increase the efficiency of electric machines in serialised production.

In the design process of a new structure for the induction motor with a stator core made from amorphous iron it is necessary to apply the circuit method and the field‐circuit method. The use of the circuit method allows quick calculations of many versions of the designed motor, but the use of the field‐circuit method is necessary for verification of the maximal value of the flux density in the entire area of the cross‐sections of the motor core.

A new construction for the small induction motor with the stator core made from amorphous iron was designed based on the classical structure of the four‐pole induction motor. In the designed motor a decrease of the electric energy costs was observed, which is much bigger than the material costs, and in effect lower total costs for the designed motor were obtained.

According to necessary changes in the motor construction, due to lower saturation limit for this material, the authors obtained a significant increase in the motor efficiency and a decrease in the total cost of the motor. The development of a new technology allows the cutting of amorphous magnetic materials and the production of electric motors from them.

This paper shows the possibility of using amorphous magnetic materials for stator core of small induction machines and the advantages of such construction for obtaining more efficient motor construction.

Applies the field/circuit two‐dimensional method and improved circuit method to engineering designs of the induction motor with stator cores made of amorphous iron. Exploiting of these methods makes possible computation of many different specific parameters and working curves in steady states for the “high efficiency” three‐phase small induction motor. Compares the results of this calculation with the results obtained for the classical induction motor with identical geometric structure.

This paper aims to present the analysis, design and implementation of functional link-based recurrent fuzzy neural network (FLRFNN) for the control of variable-speed switched reluctance generator (SRG).

The node connecting weights of the FLRFNN are trained online by back-propagation (BP) algorithms. The proposed estimator requires less processing time than traditional methods and can be fully implemented using a low-cost digital signal processor (DSP) with MATLAB toolboxes. The DSP-based hybrid sensor presented in this paper can be applied to a wind energy-conversion system where the SRG is used as a variable-speed generator. The current transducer is used to monitor the energized current and proximity sensors for rotor salient.

The authors have found that optimal based on FLRFNN with Grey controller can resolve the regulation of the system with uncertainty model and unknown disturbances. This technique can maintain the system stability and reach the desired performance even with parameter uncertainties.

This design will improve the performance of SRG to operate more smoothly. This application is currently being studied because the SRG has well-known advantages such as robustness, low manufacturing cost and good size-to-power ratio. Performance of the proposed controller can offer better stability characteristics. Finally, the SRG has a very good efficiency in the whole operating range.

The S-MCSRM is a two-phase excited switched reluctance motor (SRM), with the short flux path and mutual inductance coupling, which is suitable for the oil submersible pump application owing to large torque and three-wire connection with the standard full-bridge power converter. However, there is not literature to disclose its model due to the complicated mutual inductance coupling. The FEM model is a time-consuming method to analyze this motor. For the first time, this paper aims to propose an S-MCSRM model for performance analysis and control method developing. The proposed model would save simulation time and be a theoretical fundamental for further implementing control algorithm.

The S-MCSRM's operating principle is analyzed, and the voltage equation and the generated torque are deduced. The FEM is utilized to obtain the five typical magnetization curves that describe the S-MCSRM's magnetic path characteristic. The magnetic co-energy equation, phase torque and total torque equations are obtained. From the basic voltage equation, the S-MCSRM's state space model is built for the dynamic analysis and control purpose. The S-MCSRM is widely analyzed in detail by using the proposed model and comparison with the conventional SRM. JMAG finite element package is used to verify the proposed model.

The proposed modeling method is validated by the identical results to those from FEM-based JMAG software. The proposed model just takes second-level time, which is far less than minute-level time consuming of FEM method. The S-MCSRM generates larger torque than the conventional SRM, with three-wire and standard full bridge power converter, and it is confirmed that the S-MCSRM is suitable for the oil submersible pump applications.

This paper proposes a new modeling method for the S-MCSRM to exactly analyze the motor's operating performances, and also it is a theoretical fundamental for developing control algorithm. The proposed model saves much time in analysis, calculation, and simulation, when compared to the FEM method. The completed analysis including flux linkages, torque, torque-ripple, and torque-speed characteristic discloses the S-MCSRM's steady-state operating performances, which provides the deep insight for this kind of motor's applications.

Case management is a technology for enhancing the continuity of care provided to clients in a community-based mental health service system. From among diverse case management models, the Massachusetts Department of Mental Health adopted the service broker model for statewide implementation and identified changes in the structure of inter-occupational and interorganizational relations in the agency that would be needed to accommodate this technology. This chapter analyzes the process of implementing this technology, based on interviews with administrators of mental health service areas during the implementation period. Potential obstacles to the implementation of a new technology are discussed and the resulting variation in adherence to the selected case management model is described. Sources of conflict about the case management model and effective responses to this conflict are identified. Conflict over the new model was strongest in areas where clinicians were most powerful and where boundaries around hospitals were strongest; such conflict was often resolved by subordinating case managers to clinicians and thus reversing the intended hierarchical structure. Implementation was facilitated by bridging strategies that facilitated cooperation among case managers and clinicians.