PDFI控制下单相光伏并网逆变器的混合阻尼控制策略  

Hybrid damping strategy for single-phase grid-connected PV inverter under the control of PDFI

作　　者：杨秋霞 李坤[1] 王虎[1] 赵翠妹 

机构地区：[1]燕山大学电气工程学院,河北秦皇岛066004

出　　处：《电力系统保护与控制》2016年第16期22-27,共6页Power System Protection and Control

基　　金：国家自然科学基金资助项目(61573303);河北省自然科学基金资助项目(E2016203092)~~

摘　　要：传统的比例积分(PI)控制由于具有一定的稳态误差,无法实现对并网电流快速精确的控制,光伏系统并网以后所引入的电网电感对LCL滤波器的阻尼策略也有着不可忽略的影响。为了解决上述问题,提出了一种PDFI控制下单相光伏并网逆变器的混合阻尼控制策略。该策略介绍了比例延时反馈积分(PDFI)控制,在原有的PI控制上加上简单反馈电路,实现了并网电流的无稳态误差控制。同时分析了以阻尼系数为研究对象的混合阻尼控制,改善了电网电感对LCL滤波器的阻尼影响。理论分析、实例仿真的结果表明,该控制策略下,系统能够稳定运行,并网电流实现了精确控制,并且对电网电感具有良好的适应性。The conventional proportional-integral（PI） control can not achieve the rapid and precise control of the grid-connected current because of its steady-state error. The introduction of grid inductor also has a non-negligible impact to damping strategy of the LCL filter when the PV system connects into the grid. To overcome the problems mentioned above, this paper presents a hybrid damping control strategy for single-phase grid-connected PV inverter with the control of PDFI. This strategy introduces proportional delay feedback integral（PDFI） control which adds a simple feedback circuit to the original PI control and can achieve the control of the grid current without steady-state error. The hybrid damping control is also analyzed which takes damping coefficient as the research object, and the impact of the grid inductor to damping strategy of the LCL filter is improved with addition of the hybrid damping control. The results of the theoretical analysis and the simulation both show that the proposed strategy has a great contribution to the control of the grid current and the steady operation of the system, and also has a good adaptability to the grid inductor.

关 键 词：光伏并网逆变器 比例延时反馈积分 稳态误差 LCL滤波器 混合阻尼策略 

分 类 号：TM464[电气工程—电器]