Real Time Recognition Method for Wide Speed Range Rotor Position of Dual Three-Phase Motor based on Symmetrical Voltage Injection

The rotor position information is an important variable in the control system of dual three-phase motors, and ensuring the real-time and correct information is a prerequisite for the reliable operation of the dual three-phase motor system. The paper analyzes the structural characteristics of a dual three-phase permanent magnet synchronous motor (DTP-PMSM) with a 30°misalignment of dual Y windings, and proposes a new high-frequency symmetrical voltage injection method that can effectively identify rotor position information in a wide speed range. It forms heterogeneous information verification with the hardware signals of the dual three-phase motor rotor position sensors, improving the functional safety level of the control system. Firstly, a DTP-PMSM mathematical model was constructed under high-frequency voltage injection, and the mapping relationship between injection voltage and response current was derived, revealing the characteristic relationship between rotor position information and response current. Secondly, utilizing the structural features of DTP-PMSM, real-time rotor position information is extracted from the current response by injecting high-frequency rotating voltage into a symmetrical sequence; Finally, the proposed high-frequency rotational voltage injection method was validated through bench testing and analysis. The results show that this method can effectively extract high-precision rotor position information over a wide speed range, meeting the needs of monitoring rotor position sensor information. The rotor position recognition accuracy of this method is high, and it also has good rotor position estimation performance in the steady-state and dynamic operation of the motor.