Sensorless Control Strategy for Multiphase Induction Motor with Stator and Rotor Resistance Identification Based on Injecting Third Harmonic Current

An Online VSI Error Parameter Identification Method for Multiphase IM With Non-Sinusoidal Power Supply

“…According to (15), when seven-phase sinusoidal current is injected into the seven-phase induction motor, the voltage error generated by the inverter of phase A is shown in the Fig. 5.…”

“…Third harmonic current injection is widely used in multiphase motor control to improve torque performance [11]- [14]. An accurate flux observer is of great help to multiphase motors [14], [15]. However, voltage distortion has non-ignorable influence on flux observer at low speed.…”

“…At the same time, by using the degree of freedom of the harmonic plane, the parameters of voltage error can be identified on the harmonic plane with a MRAS and compensated to the given voltage. This identification method is mainly used to estimate speed and other motor parameters [15], [27]- [29]. A new adaptive law is designed for inverter voltage error identification.…”