Motor Current Reconstruction Method Using Single Shunt Resistance by High-Frequency Voltage Injection

This paper describes a novel method for current detection in sensorless control using high-frequency voltage injection. The method adopts a low-pass filter to prevent ringing. In general, reactive current cannot be detected using a DC current filter, but this method permits the detection via voltage injection. High responsiveness and simple constitution were achieved using the method. Simulation results indicate that active and reactive currents can be reconstructed using a single shunt current; the experimental results indicate that this method can be applied to a motor drive without lowering the performance compared to when using the current sensor.