风电变流器电网不平衡优化控制策略  

Optimized Control Strategy for Wind Power Converter Under Unbalanced Grid

作　　者：陈佳明 周党生 喻俊鹏 徐晓峰 

机构地区：[1]深圳市禾望电气股份有限公司,广东深圳518055

出　　处：《电力电子技术》2017年第7期40-43,92,共5页Power Electronics

基　　金：国家科技支撑计划项目(2015BAA07B00)~~

摘　　要：处于薄弱电网中的风电变流器,时常要面临电网电压瞬变、谐波和不平衡等恶劣状况,而电网不平衡为其中最常见的一种。针对不平衡电网电压时风电变流器网侧存在的电流畸变、有功功率振荡及由其导致的直流母线电压脉动和电流不平衡问题,在分析其产生原因的基础上,结合变流器的输出能力特性和电能质量的要求提出一种轻度不平衡下消除有功功率振荡、深度不平衡下维持网侧电流平衡的自适应优化控制策略。通过在正序d,q坐标系比例积分(PI)调节的基础上并联多谐振控制器的方法来确保电流的跟踪效果。平台实验验证了控制策略的有效性和优势。Wind power converter usually locates in remote areas where grid is relative weak, are often faced up with grid problems like voltage transients ,harmonic distortion and unbalanced grid voltage.And the well known grid voltage unbalance problem is one of the most concerned issues in recent years.Mechanism of power oscillation as well as its resultant converter direct current-link voltage fluctuation ,grid side current distortion and imbalance phenomenon are analyzed.To solve unfavorable influences brought by unbalanced grid voltage,an adaptive control scheme is proposed according to the converter output characteristics and the inherent power quality requirements.With the optimized scheme, the converter control system would automatically eliminate under mild unbalanced voltage situation and when the unbalanced condition become worse,it would turn to keep the grid side current balance.The optimized control target can be ensured by using multiple resonant controller structure in the positive d,q reference frame where a proportional integral（PI） controller is already implemented.Experimental platform results verify its feasibility and advantage.

关 键 词：风电变流器 电网不平衡 电能质量 自适应控制 

分 类 号：TM46[电气工程—电器]