无锁相环方法综述  

An Overview of Non-PLL Methods

作　　者：雷芸[1,2] 肖岚[1] 郑昕昕[1] 

机构地区：[1]江苏省新能源发电与电能变换重点实验室,南京航空航天大学,江苏南京210016 [2]南京理工大学,江苏南京210094

出　　处：《电力电子技术》2015年第6期104-108,共5页Power Electronics

基　　金：国家自然科学基金(51377082);江苏省产学研前瞻性联合研究项目(BY2012021)~~

摘　　要：并网功率变换器对锁相环(PLL)的性能要求很高,然而由于电网电压存在不平衡和频率偏移问题,电网电压的检测和锁相角计算过程会产生一定误差,因此无PLL控制策略得到越来越多的重视。介绍了现有无PLL的电流检测法工作原理,分析了其优缺点。针对三相并网逆变器提出了一种改进型无PLL空间矢量脉宽调制(SVPWM)控制方法,使控制不受电网不平衡情况的影响,通过仿真和实验验证了理论分析。最后以该逆变器为例,参考各种无PLL电流检测方法,对逆变器的无PLL控制策略进行实验,并从动态响应速度、适用性与算法复杂性等角度进行对比,指出了无PLL控制策略研究难点和今后研究方向。Grid-connected power converters require high performance of phase-locked loop （PLL）.However, the grid voltage unbalance and frequency shift may exit.The detection of grid voltage and calculation of phase angle may have error,which would influence control precision.Hence control strategies without PLL are paid more attention.This paper presents a survey on existing non-PLL methods for real-time detection of currents to analyze the advantages and disadvantages.This paper also proposes an improved space vector pulse width modulation（SVPWM） control strategies without PLL for three-phase inverter.The simulation and experiment show that the algorithm can improve control precision effectively under unbalanced voltage.Refer to non-PLL methods for the current detection,control strategies with- out PLL for inverter are experimented.And these strategies are summarized and compared by dynamic response, applicability and complexity.And then difficulties and trends of the research on fault diagnosis of inverters are indicated.

关 键 词：变换器 无锁相环 空间矢量脉宽调制 电流检测 

分 类 号：TM46[电气工程—电器]