Winding current waveform controlling method for switch reluctance motor braking process

Abstract

The invention provides a method for controlling the winding current waveform in the braking process of a switch reluctance motor, which comprises: a step of braking operation by the motor, during which the positive voltage is adopted to increase the current in the initial segment of the electrifying interval; a step of adopting negative voltage to reduce the current after the current increases to the specified value and the winding current is larger than the specified current; a step of increasing the winding current by adopting zero voltage when the winding current is less than the specified current; and a step of adopting the positive voltage compensation to increase the current if the winding current is reduced when zero voltage is adopted or the current does not increase to the specified value after the zero voltage with n periods is adopted continuously. The method has the advantages that the braking current waveform of the winding can track the specified waveform well, the current waveform has good smooth property, and the output torque pulse of the motor is effectively reduced.

Description

technical field [0001] The invention relates to a current control method, in particular to a winding current waveform control method suitable for the braking process of a switched reluctance motor with any number of phases and any structure powered by an independent half-bridge power circuit for each phase winding. Background technique [0002] The stator and rotor of the switched reluctance motor are double salient pole structures, which are made of laminated silicon steel sheets. There are concentrated windings on the stator poles and no windings on the rotor. Switched reluctance motors can be designed with different winding phases and different stator and rotor poles, such as three-phase 6 / 4 poles, three-phase 12 / 8 poles, four-phase 8 / 6 poles. [0003] The switched reluctance motor is powered by the power circuit, figure 1 It is a topology of a one-phase power circuit with two switches. The power supply in the figure can be a storage battery or a rectified and filtered...

AI Technical Summary

Problems solved by technology

But if the motor speed is high, then Relatively large, and R i can be ignored, using zero voltage, it can be seen from formula 2 that the current rises at a faster rate; if positive pressure is used, it can be seen from formula 1 that the current rises faster, which will cause the winding current to run out of control

[0014] These two braking control methods have large winding current fluctuations and poor current waveform smoothness, which is not conducive to reducing the output torque ripple of the motor.

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