伺服阀旋转直驱超声电机机理与特性

Principle Design and Characteristic Analysis of Ultrasonic Motor for Direct Drive Servo Valve

摘要:

针对某旋转直驱式伺服阀对驱动电机小长径比紧凑型结构形式的设计要求，从伺服阀功率级200 Hz动态响应需求出发，设计了一款环形行波型超声电机。分析了超声电机的基本工作原理并建立了超声电机定子转子摩擦传动模型，搭建了超声电机特性测试实验台并进行了转矩-转速测试，实验结果与仿真结果一致，验证了电机设计的合理性。在此基础上，进行了超声电机驱动频率和驱动电压的影响特性分析，结果表明超声电机在49.8 kHz的驱动频率下具有最大的工作效率，驱动电压大于110 V时可以满足伺服阀转速与转矩工作需求，并且在49.8 Hz的驱动频率和110 V驱动电压条件下可以接近最大的工作效率。

Abstract:

To meet the design requirements of a rotary direct-drive servo valve for a small length-to-diameter ratio compact structure of the drive motor， an annular traveling wave type ultrasonic motor was designed starting from the demand of 200 Hz dynamic response of the servo valve power level. The basic working principle of the ultrasonic motor is analyzed and the stator-rotor friction transmission model of the ultrasonic motor is established. An ultrasonic motor characteristic test bench was built and the torque-speed test was conducted， based on which， the analysis of the influence characteristics of ultrasonic motor drive frequency and drive voltage was performed. The results show that the ultrasonic motor has the maximum working efficiency at a drive frequency of 49.8 kHz， the servo valve speed and torque working demand can be satisfied when the drive voltage is greater than 110 V， and the maximum working efficiency can be approached under a drive frequency of 49.8 Hz and 110 V drive voltage condition.