Pseudo-Random High-Frequency Sinusoidal Voltage Injection Based Sensorless Control for IPMSM Drives

A sensorless control method based on pseudo-random high-frequency(HF) sinusoidal voltage injection is studied to solve the noise problem caused by the conventional HF injection strategy in this paper. In the low-speed and zero-speed range, HF injection strategy is widely used as a sensorless control strategy for IPMSM drives. However, the harsh noise caused by the HF signals is unexpected. By injecting two HF signals with different frequencies in a random manner, instead of traditional fixed frequency signal, noise problems can be attenuated while sustaining the estimation accuracy. The signal processing is analyzed to select the frequency and amplitude of the pseudo-random high-frequency (PRHF) sinusoidal signals. This method is verified by simulation and experiment on a 2.2-kW IPMSM drive platform.