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 proposed method adopts a low-pass filter to prevent ringing. Generally, reactive current cannot be detected using a DC filter; however the proposed method permits detection via voltage injection. High responsiveness and a simple construction have been 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 the proposed method can be applied to a motor drive without lowering the performance, unlike when using a current sensor.