Implementation of the Three-Phase Switched Reluctance Machine System for Motors and Generators

This paper presents two three-phase switched reluctance machine systems. One is the dual motors drive for the electric locomotive traction; the other is the variable-speed generator system for wind power applications. The principles of the switched reluctance machine system operated at four quadrants, the scheme of the symmetrical traction at quadrant I and quadrant III, and the scheme of the symmetrical regenerative braking control at quadrant II and quadrant IV, are given. The transient phase current analysis and the energy analysis of the switched reluctance machine system at the operational state of braking or generating are evaluated, and the rotor position and the peak value of the phase current at three different conditions are given. The closed-loop rotor speed control of the main motor, synchronization of the rotor speed, and balance distribution of loads between the main motor and the subordinate motor have been implemented by the fuzzy logic algorithm. The closed-loop output power control of the switched reluctance wind power generator system implemented by regulating the turn-on angle of the main switches with fuzzy logic algorithm and fixed turn-off angle of the main switches is also presented. The major components of the two prototypes are explained in detail. The experimental results of the dual 7.5-kW three-phase 6/4 structure switched reluctance motors (SRMs) parallel drive system prototype are included. It is shown that the maximum difference in the output torque of the two motors at the same given rotor speeds is within 10.00% and the maximum difference in the practical rotor speed of the two motors is within 5.00%. The tested results of three-phase 12/8 structure switched reluctance variable-speed wind power generator system show that the error of the closed-loop output power control is within 2.2%, while the rotor speed range is close to the ratio of 1:3 with the low rotor speed 405 r/min. The average dc line current of the power converter can be utilized as a feedback signal for the actual output torque of SRM drive or a feedback signal for the actual output power of switched reluctance generator system.