Research on rotating encoder zero-position location based on missile steering gear

Permanent magnet synchronous motor (PMSM) is applied to aerospace missile steering gear as the structure of servo position with excellent performance of small volume, precision and reliability. For reducing error of actuator, it is important that initial position of actuator should keep consistent with rotor's initial position because the dynamic key parameters of servo system are influenced by rotor position. Therefore, it is a key point that actuator's zero position and rotating encoder rotor's should be coincident. In this paper, rotating encoder is applied to position sensor in missile steering gear servo system for testing rotor position, and the method of confirming initial position is advanced, then the method which keeps actuator's zero position and rotating encoder rotor's being coincident is advanced. The better control effect is attained by combining space vector control strategy.