摘  要：根据超声波电动机对其驱动控制单元的要求，设计了一种用于超声波电机驱动的DDS信号发生器。该信号发生器基于可编程逻辑器件（CPLD）实现，能够给出频率及相位差可调的两路正弦信号，信号特征符合超声波电机驱动需求。DDS信号发生器处于超声波电机控制系统的前向通道中，其误差分析不仅可以指导DDS信号发生器的设计，而且对于提高系统动态控制性能具有重要意义。针对超声波电动机驱动应用场合，对DDS信号发生器进行了详细的误差分析，给出了定量分析结果。
关键词：超声波电动机；误差分析；直接数字频率合成；定量分析

Abstract: According to ultrasonic motor drive control unit,designed a DDS signal generator for ultrasonic motor-driven.The signal generator based on the CPLD,it generated the two sinusoidal signals with frequency and phase difference adjustable，and the signal characteristics with ultrasonic motor-driven demand.DDS signal generator at the front of ultrasonic motor control system,its error analysis not only could guide the design of DDS signal generator，but also had a great significance to improve the dynamic performance.According to ultrasonic motor application,this paper detailed error analysis of DDS signal generator,and gave the results of quantitative analysis.
Key Words: Ultrasonic motor;Error analysis;DDS;Quantitative analysis