New Pulse High-frequency Signal Injection without Position Sensor Control

Aiming at the problem that the traditional pulse high-frequency voltage injection method is easy to cause the instability of the position estimation system, a new Q-axis high-frequency current response phase modulation signal method is constructed by locking the Q-axis by using phase-locked loop technology. A new position estimation compensation strategy and a rotor position estimation strategy based on the pulsating high-frequency current injection method for permanent magnet synchronous motors are proposed to effectively avoid the backpotential caused by the increase in speed and the increase in position estimation error caused by the cross-coupling term as well as the instability of the estimation system; the feasibility and effectiveness of the method are demonstrated through experiments.