永磁交流伺服系统电流环带宽扩展研究  

Current Loop Bandwidth Expansion for Permanent Magnet AC Servo System

作　　者：王宏佳[1] 杨明[1] 牛里[1] 徐殿国[1] 

机构地区：[1]哈尔滨工业大学电气工程系,黑龙江省哈尔滨市150001

出　　处：《中国电机工程学报》2010年第12期56-62,共7页Proceedings of the CSEE

基　　金：国家863高技术基金项目(2008AA042602)~~

摘　　要：在数字控制交流伺服系统中,制约电流环带宽的因素主要包括功率器件的开关频率和A/D采样时间、计算处理、PWM占空比更新等数字控制延时。开关频率的提高会带来开关损耗的增加,因此,在不改变功率器件开关频率的前提下扩展电流环的带宽很有必要。在同步旋转坐标系下的电流解耦控制基础上,分析了永磁交流伺服系统中电流采样和占空比更新方式产生的延时对电流环带宽的影响,并提出了带宽扩展策略,在一个载波周期内实现定子电流的双次采样和PWM占空比双次更新。在保持开关频率不变的情况下,理论上可扩展电流环带宽1倍以上,从而可以大幅提高永磁交流伺服系统的动态性能,仿真和实验结果验证了理论分析的正确性和方法的有效性。In digital control AC servo system, there are two major factors restricting current loop bandwidth, switching frequency and digital delay which means the sum of time durations of A/D sampling, algorithm execution and PWM duty cycle update delay. The switching losses will rise with the switching frequency increase. So expanding the current loop bandwidth is necessary, without changing the switching frequency. The delay effects of current sampling and duty cycle update were analyzed and the bandwidth expansion strategy was proposed. Double stator current sampling and double PWM duty cycle update were achieved in a carrier period. The current loop bandwidth can be extended more than one time theoretically and the dynamic performance of servo system is improved. Simulation and experimental results verify the validity of the theoretical analysis and the feasibility of the method.

关 键 词：永磁同步电机 带宽 电流采样 占空比更新 

分 类 号：TM315[电气工程—电机]