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This paper describes a full digital system to control a permanent magnet synchronous motor (PMSM) used in electric vehicle (EV) driving by TMS320C240 DSP. In view of the operation characteristic of EV, a fuzzy-PI control strategy is presented based on the field orientated control (FOC) and space vector technique in order to utilize reluctance torque of PMSM effectively. Due to the compensation for torque changes resulting from d-axis current in real-time, the system maintains high efficiency in all range of speed. The combination of fewer components and the improved control strategy enables the system to fulfil enhanced operation performance of EV.

The leakage magnetic fields due to heavy current leads of bushings belong to 3D open boundary fields in a large transformer. The distributions of the fields are calculated by 3D geometric transform method. The eddy current densities and loss in the ascending flange are analyzed at the different materials and thickness of copper screen.

This paper presents a type of hybrid excitation synchronous generator (HESG) without brush and slip ring. Due to its special structure, the 3D finite element method is used to analyze the magnetic field of the generator and the calculation results can be guidance to parameter calculation.

Permanent magnet synchronous motor (PMSM) has a excellent performance and will see a wide use in electric vehicle (EV) application. But some improvements should and can be done to make it more suitable in an EV drive. In this paper, asymmetric airgap and its optimal design, field and circuit coupled design method and winding switch of PMSM are put forward and analyzed, and are verified to be valid by experiment or simulation.

The paper presents a novel artificial neural network (ANN) based PID speed controller for a permanent magnet synchronous motor (PMSM) drive system. The ANN PID scheme is a MIMO controller and operates using the max-torque/current control strategy A general computer is used as hardware platform. Simulation and experiment results verify the success of a drive system with this ANN PID speed controller.

In this paper, the temperature rises of a winding for a transformer with forced-directed oil are computed with the developed mathematical model and numerical model, and the results are given and compared with experimental values. The developed mathematical model is briefly described in the paper. The distribution of winding temperature rise is analyzed.

For permanent magnet synchronous generators, it is difficult to control the air gap magnetic flux, because the magnetic flux is determined by the property of permanent magnet and approximately kept constant. In this paper, a novel hybrid excitation permanent magnet synchronous generator (HEPMSG) is presented, which has the advantages of electric excitation and permanent magnet machines: (1) it has no brushes, and (2) it is easy to get magnetic flux control. The structure and operating principle are described. An example is given in the paper and the results are confirmed by experiments.

Rare earth permanent magnets (REPMs) feature high magnetic performance, and are very suitable for use in electric machine applications. In this paper, some calculation and analysis methods of REPM electric machines are given and summarised. Some kinds of REPM machines developed in China's Shenyang University of Technology are also presented.

Improvements on an intelligent simulated annealing (ISA) algorithm for the optimal design of electromagnetic devices is investigated in this paper. By using a fuzzy inference method, the ISA can not only reject infeasible design schemes before design calculation, but can also circumscribe the whereabouts of the global optimum and automatically narrow the search scope. In case of making improper decisions in ISA searching, a criterion of recognizing error judgment is developed. The algorithm is applied to the optimal design of induction motors used in electric locomotives, and satisfactory results are achieved.

This paper presents experimental and theoretical research on noise and vibration characteristics of a large-capacity permanent magnet synchronous machine. Some mathematical models of noise control of electromagnetic, aerodynamic and mechanical origins are established and applied to the machine design.