电网不平衡时采用改进无差拍控制的并网变流器不同约束条件的实现  

Implementations of Different Constraint Conditions Based on Improved Deadbeat Control for Grid-connected Converter Under Unbalanced Grid Voltage

作　　者：姜卫东[1] 汪磊[1] 王永生[1] 姚瑱 丁星星[1] 

机构地区：[1]合肥工业大学电气与自动化工程学院,安徽省合肥市230009 [2]南京埃斯顿自动控制技术有限公司,江苏省南京市210000

出　　处：《中国电机工程学报》2017年第6期1777-1786,共10页Proceedings of the CSEE

摘　　要：介绍在电网电压不平衡下并网变流器在αβ坐标系的数学模型。采用无差拍控制(deadbeat control,DBC)方法跟踪给定电流实现电网电压不平衡时的3种约束条件,不需要提取并网电流中的正负序分量。针对DBC方法的延时补偿问题,采用两步预测的方法补偿控制延时。在实际系统中,电流采样误差不可避免,为了抑制采样误差对电流控制的影响,提出一种带电流校正的改进DBC方法,提高系统的干扰抑制能力。最后,搭建三相并网变流器的实验平台,完成相关实验,验证所提出控制方法的有效性。The mathematical model in aft frame of a grid connected converter was described under unbalanced grid voltage. Deadbeat control （DBC） method was adopted to track reference currents to implement different constraint conditions. Then positive and negative sequence components were not required to be separated from grid connected currents. To the problem of delay compensation in DBC, a two-step prediction method was used to compensate time delay. However, in a practical system, sampling errors of currents are inevitable. In this paper, an improved DBC method with current correction was proposed to suppress sampling errors, which can improve the capability of interference suppression for system. Finally, the experimental setup of a grid-connected converter was built, and the effectiveness of the proposed method was verified by experimental results.

关 键 词：不平衡电网电压 无差拍控制 延时补偿 采样误差 干扰抑制 

分 类 号：TM46[电气工程—电器]