Four-phase switched reluctance motor torque ripple two-level suppression method

A method for torque pulsation two-level suppression of four-phase switched reluctance motor, comprising the steps of:

• a. setting a first group of torque thresholds (th1low, th1up) in a rotor position interval [0°, θr/4], and setting a second group of torque thresholds (th2low, th2up) in a rotor position interval [θr/4, θr/2], wherein, these four torque thresholds meet following requirements:
• th1up>th2up>0 (1)
• th2low<th1low<0 (2)
• |th1up|=|th2low| (3)
• |th2up|=|th2low| (4)
• wherein, a rotor position 0° is the minimum phase inductance position, a rotor position θr is the pitch angle of one rotor cycle, and a half rotor cycle is θr/2;
• b. setting a power supply excitation state of phase A as excitation state SA, wherein, excitation state SA=1 indicates a power supply excitation voltage of phase A is positive, and excitation state SA=−1 indicates a power supply excitation voltage of phase A is negative;
• setting a power supply excitation state of phase B as excitation state SB, wherein, excitation state SB=1 indicates the power supply excitation voltage or phase B is positive, and excitation state SB=−1 indicates a power supply excitation voltage of phase B is negative;
• setting an expected total smooth torque as Te;
• c. supplying power supply excitation to an adjacent phase A and phase B, wherein, the power supply excitation of phase A is ahead of the power supply excitation of phase B by θr/4;
• at this moment, phase A is turned off, while phase B is turned on;
• thus, by commutation process of dividing into two intervals from phase A to phase B, torque pulsation two-level suppression of the four-phase switch reluctance motor is realized.