Abstract:

As a three-phase power electronic device that emulates the characteristics of motor ports， the electric machine emulator （EME） provides an efficient test method for the testing of electric drive systems. The main sign of EME's restoration of the target motor port characteristics is to accurately restore the working current of the target motor， though the existing research has realized the reduction of the fundamental current and the lower order harmonic current， the restoration of the high-frequency ripple current of the motor driven by the motor controller still relies heavily on the matching of the filter inductor and the inductance of the target motor， which reduces the versatility of the EME. Therefore， based on the circuit equivalence virtual method， the equivalent circuit of PMSM is divided into two parts， with one part replaced by the actual circuit of EME， and the other part emulated by the control algorithm. Then， combining with the predictive control of the non-differential beat current， the control differential beat is compensated and the feedforward decoupling non-differential beat current following strategy is proposed. The experimental results show that based on the newly proposed port simulation algorithm of the permanent magnet synchronous motor， the EME can emulate PMSM with different parameters without replacing the inductor， with the frequency domain tracking error of high-frequency ripple current reduced from 160% to 20% of the traditional strategy， which significantly improves the emulation accuracy of the EME for the port-characteristics of PMSM.

Key words: electric vehicle, electric machine emulator, feedforward decoupling control, motor control