考虑锁相环影响的LCL型并网变换器电流环控制器参数设计  

Design of LCL-type Grid-connected Converter Current Loop Controller Parameters Considering Effects of Phase Locked Loops

作　　者：周诗颖[1] 邹旭东[1] 童力 朱东海[1] 高晓璐[1] 赵迎迎[1] 康勇[1] 

机构地区：[1]强电磁工程与新技术国家重点实验室(华中科技大学),湖北省武汉市430074 [2]浙江省电力公司电力科学研究院,浙江省杭州市310014

出　　处：《中国电机工程学报》2016年第4期1075-1089,共15页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51477064);国家重点基础研究发展计划项目(973计划)(2012CB215100)~~

摘　　要：通常风电场位于大电网的末端,并网端口电压的大幅波动将引起锁相环不同程度的暂态响应,使并网系统无法呈现预期的控制性能,甚至出现暂态不稳定的现象。考虑锁相环的暂态特性以及线路参数对大功率直驱风电系统中LCL型并网变换器电流控制性能的影响,提出了一种基于多目标函数的电流环PI控制器参数设计方法。首先,建立了并网电流控制系统的精确静态模型。在此基础上,通过对系统响应特性的幅值裕度、相位裕度和静态误差的分析,得到了满足上述要求的PI控制器参数取值范围。随后,建立了受锁相环性能影响的并网电流控制系统的暂态模型,进一步对已有的PI参数取值区间进行优化,得到了性能更优的控制器参数组合。最后,基于典型参数下1.5 MW的LCL型并网变流器进行了仿真分析,在10 k W的直驱式风力发电并网变流器样机上进行了实验验证。结果表明,该方法可全面改善并网电流控制的动静态响应特性以及对电网环境的适应能力。Wind farms are usually at the end of the grid, grid port voltage fluctuations will cause varying degrees of phase locked loop （PLL） transient response, so that the grid system cannot render the expected control performance, even leads to instability. Considering the impact of PLL transient characteristics and line parameters on high-power direct drive wind power system converters with LCL filter current control performances, in this paper a current loop PI controller parameter design method based on the multi-objective function was proposed. Firstly, a precise static model of grid-connected current control systems is established. Based on this, by analyzing the amplitude margin, the phase margin and the static errors of the system response characteristics, the PI controller parameter ranges meeting the above requirements had been achieved. Subsequently, a transient grid-connected current control system model affected by phase locked loop performance was established, furthermore the existing PI parameters value interval was optimized to obtain a better performance of the controller parameter combinations. Finally, 1.5 MW LCL type grid-connected converter simulation results and 10 kW experimental platform verification showed that, this method can improve both the static and dynamic responses of the current control and adaptability to the grid environment.

关 键 词：LCL型并网变换器 PI控制器 多目标函数 线路参数 锁相环 

分 类 号：TM46[电气工程—电器]