Analysis and Optimization of Transmission and Control Characteristics of Micro-Flow Rotary Direct-Drive Servo Valve

Abstract:

Aimed at the micro-flow servo control requirements of fuel metering system and thrust vector system of small aircraft such as un-manned aerial vehicle， tactical missile and regional civil aviation， the size constraint and design analysis of key structures such as eccentric ball pair transmission interface and non-full-circle throttle valve port of rotary direct-drive servo valve is conducted. The optimization analysis of important parameters such as throttle valve port width， ball pair eccentricity， and driving motor moment of inertia is performed， and the optimization interval of servo valve structure design is given. In addition， a double closed-loop control method for motor angle and current is proposed. The measured results of amplitude-frequency response are consistent with the theoretical analysis， and the high frequency response above 200 Hz meets the actual requirements. The double closed-loop control method greatly reduces the response overshoot of servo valve and improves the stability.