孙正海 王剑平 杨晓红等

摘要對SVPWM伺服系统死区效应及在线死区补偿方法进行了探讨。常用的平均死区时间补偿技术是根据参考电压伏秒面积等于补偿后伏秒面积原则，由于难以准确地得到电流的极性所以可能出现误补偿。该文在分析了死区效应对输出电压电流影响的基础上，提出了一种低成本的死区补偿方法。并通过将相电流进行旋转坐标变换计算电流矢量角，间接判断电流极性准确的求出了电流的过零点，从而得到较好的补偿效果。最后在基于TMS320F2812研发的伺服驱动器上测试软件，结果证明了该方法的正确性，有效地减小了死区时间造成的电流畸变并使零电流箝位现象得到明显改善。

关键词死区补偿；在线测量；零电流箝位；伺服系统

中图分类号S22文献标识码A文章编号0517-6611（2015）31-340-04

Online Novel Deadtime Compensation Method of Agricultural Servo Motor

SUN Zhenghai， WANG Jianping*， YANG Xiaohong et al

（College of Information Engineering and Automation， Kunming University of Science and Technology， Kunming， Yunnan 650500）

Abstract The deadtime effect of SVPWM servo system and online deadtime compensation method was discussed. Common average deadtime compensation is based on the principle that the voltsecond area of reference voltage equals to the voltsecond area after compensation. It is difficult to obtain accurate polarity of the current， so error compensation may appear. After analyzing the dead zone effect on the output voltage and current influence， this article proposes a lowcost method of deadtime compensation. And by the phase current rotating coordinate transformation to calculate the current vector angle， indirectly determining the current polarity， it can accurately calculate current zero crossings and obtain better compensation effect. Finally， based on TMS320F2812 developed low pressure servo drive test software. It proves the correctness of the method which effectively reduces the dead time caused by the current distortion and zerocurrent clamping phenomenon has been significantly improved.

Key words Deadtime compensation； Online measurement； Zerocurrent clamp； Servo system

目前伺服电机在农业方面的应用越来越广泛，而对于理想的农业伺服电机功率器件而言，门级驱动信号应该是互补的。但是对于实际的功率器件而言，为了防止上下桥臂的开关直通，两个开关需要加入一段死区时间，正是这段空白时间使得输出电压和实际给定电压之间存在误差。而每个斩波周期内引起的微小畸变积累起来就会造成严重的波形失真和基波电压降。随着开关频率的增大，电压失真和谐波成分也越大。由死区时间造成的死区效应会使输出电压电流畸变，出现零电流箝位现象以及转矩、转速脉动，严重影响了伺服驱动器的性能[1-3]。……