FAULT-TOLERANT VECTOR CONTROL METHOD FOR NON-ADJACENT TWO-PHASE SHORT CIRCUITS OF FIVE-PHASE PERMANENT MAGNET EMBEDDED FAULT-TOLERANT LINEAR MOTOR

摘要

Disclosed is a fault-tolerant vector control method for non-adjacent two-phase short circuits of a five-phase permanent magnet embedded fault-tolerant linear motor. Firstly, according to the principle that a magnetomotive force remains unchanged before and after this two-phase open-circuit fault and the sum of non-fault-phase currents is equal to zero, a popularization Clarke transformation matrix is deduced by taking the condition that amplitude values of adjacent two-phase currents are equal as a constraint condition; a counter electromotive force is estimated by adopting a transpose of the matrix; a nonlinear strong coupling system of the motor in a fault state is converted into a first-order inertial system by adopting an internal model controller, a first-order inertia feedforward voltage compensator and a counter electromotive force observer; a short-circuit compensation voltage is obtained according to the principle that a synthesized magnetomotive force of a non-fault-phase short circuit compensation circuit and two short circuit fault phase currents is equal to zero; and the voltage is overlaid with an output voltage of a vector controller. The control method suppresses a thrust ripple of the motor caused by non-adjacent two-phase short-circuit faults of the motor; more importantly, the dynamic performance and the steady-state performance thereof are consistent with those in a normal state; and an on-off frequency of a voltage source inverter is constant.