基于比例积分谐振调节的光伏并网逆变器电流控制方法

doi:10.16183/j.cnki.jsjtu.2018.12.014

摘要/Abstract

摘要： 为解决电网电压畸变影响光伏逆变器电流控制性能的问题，提出一种基于比例积分谐振(PIR)调节器的电流控制方法.首先确定了光伏逆变器含有电流内环、直流电压外环的控制结构，PIR调节器用于对电流内环中电网电压畸变扰动的抑制与基波电流的跟踪.由于光伏逆变器的LCL滤波器与PIR调节器阶数较高，在设计控制参数时面临诸多问题，接着提出一种基于离散系统根轨迹法的PIR调节器参数设计方法，避免了连续域设计的调节器参数直接应用于数字控制器，从而引发调节器性能偏差甚至失稳.分析结果显示，在电网频率以及LCL滤波器参数变化时，设计参数依然可使系统具有较好的适应性.最后在Simulink上搭建仿真模型，验证了基于PIR调节的电流控制方法的可行性以及所设计调节器参数的正确性.

关键词: 光伏逆变器, 电网电压畸变, LCL滤波器, 比例积分谐振(PIR)调节器, 离散系统根轨迹

Abstract: To solve the problem of grid voltage distortion affecting the current control performance of photovoltaic inverter, a current control strategy based on proportional-integral-resonant (PIR) regulator is proposed. Firstly, the control structure of photovoltaic inverter with inner current-loop and outer DC voltage-loop is determined. PIR regulator is used to suppress the grid voltage distortion or disturbance in inner current-loop and track the fundamental current. Due to the high orders of the LCL filter and PIR regulator in the photovoltaic inverter, there are many problems in the design of control parameters. Then, a parametric design method of PIR regulator based on the discrete-time root locus is proposed, which avoids the performance deviation or unstability of the regulator when the regulator parameters based on continuous domain are directly applied to the digital controller. Analysis results show that the design parameters can still make the system have a good adaptability during the changes of the grid frequency and LCL filter parameters. Finally, a simulation model based on Simulink verifies the feasibility of the current control strategy based on PIR regulator and the correctness of designed controller parameters.

Key words: photovoltaic inverter, grid voltage distortion, LCL filter, proportional-integral-resonant (PIR) regulator, discrete-time root locus

中图分类号:

TM 464

支琴a，吴映阳b，金之俭b，沈海军a. 基于比例积分谐振调节的光伏并网逆变器电流控制方法[J]. 上海交通大学学报（自然版）, 2018, 52(12): 1642-1648.

ZHI Qin,WU Yingyang,JIN Zhijian,SHEN Haijun. Current Control Strategy for Photovoltaic Grid-Connected Inverter Based on PIR Regulator[J]. Journal of Shanghai Jiaotong University, 2018, 52(12): 1642-1648.

参考文献

［1］张尧, 晁勤, 吴春艳, 等. 光伏并网逆变器研究综述［J］. 电器与能效管理技术, 2016 (17): 7-11. ZHANG Yao, CHAO Qin, WU Chunyan, et al. Researching review of photovoltaic grid-connected inverter［J］. Electrical and Energy Management Technology, 2016 (17): 7-11. ［2］徐强, 张海燕, 张莉, 等. 电网电压不平衡和畸变的双馈风电锁相环研究与设计［J］. 电器与能效管理技术, 2015 (19): 39-44. XU Qiang, ZHANG Haiyan, ZHANG Li, et al. Research and design of PLL for DFIG-based wind power with unbalanced and distortion grid voltage［J］. Electrical and Energy Management Technology, 2015 (19): 39-44. ［3］何娈, 王昕, 周荔丹, 等. 混合调制 SVG 直流侧平衡新方法的研究与试验［J］. 电器与能效管理技术, 2015 (6): 33-38. HE Luan, WANG Xin, ZHOU Lidan, et al. Study of a new DC balance control method for hybrid modulated cascade SVG［J］. Electrical and Energy Management Technology, 2015 (6): 33-38. ［4］林海雪. 分布式电源的并网标准及其发展趋势［J］. 电器与能效管理技术, 2016(17): 1-6. LIN Haixue. On the standard for grid-connected of distributed resources and its developmental trend［J］. Electrical and Energy Management Technology, 2016 (17): 1-6. ［5］贺春, 赵书强, 魏晓光, 等.谐波畸变下电网的无功优化［J］. 电力自动化设备, 2003， 23(1): 14-17. HE Chun, ZHAO Shuqiang, WEI Xiaoguang, et al. Reactive power optimization for system network accompanied with harmonic distortion［J］. Electric Power Automation Equipment, 2003, 23(1): 14-17. ［6］魏薇, 史林军, 赫卫国, 等.含STATCOM的风电场级多PI控制器参数优化［J］.广东电力, 2018, 31(9): 62-69. WEI Wei, SHI Linjun, HE Weiguo, et al. Optimization on parameters of multi-PI controller of wind farm with STATCOM［J］. Guangdong Electrical Power, 2018, 31(9): 62-69. ［7］于龙, 傅仲文, 唐圣学.基于神经网络PI+自适应重复控制的并网逆变器研究［J］. 可再生能源, 2018, 36(11): 1670-1676. YU Long, FU Zhongwen, TANG Shengxue. Research on grid connected inverter based on neural network PI+ adaptive repetitive control［J］. Renewable Energy Resources, 2018, 36(11): 1670-1676. ［8］熊平化, 孙丹, 邓伦杰.广义谐波电网环境电压源型并网变流器滑模变结构直接功率控制策略［J］.电网技术, 2016, 40(6): 1845-1850. XIONG Pinghua, SUN Dan, DENG Lunjie. Improved sliding-mode-based direct power contorl stra-tegy of grid connected voltage sourced converter under universal harmonic grid［J］. Power System Technology, 2016, 40(6): 1845-1850. ［9］杨苹, 郑远辉, 许志荣, 等.基于准比例谐振积分与重复控制的光伏并网逆变器研究［J］.可再生能源, 2015, 33(7): 993-998. YANG Ping, ZHENG Yuanhui, XU Zhirong, et al. Study on photovoltaic grid-connected inverter based on quasi-PRI and repetitive control［J］. Renewable Energy Resources, 2015, 33(7): 993-998. ［10］程鹏, 年珩. 电网电压不平衡时基于谐振闭环调节的双馈异步发电机转矩波动抑制策略［J］. 中国电机工程学报, 2015, 35(7): 1756-1767. CHENG Peng, NIAN Heng. Torque ripple restraint strategy of DFIG under unbalanced grid voltage conditions based on resonant control loop［J］. Proceedings of the CSEE, 2015, 35(7): 1756-1767. ［11］赵新, 金新民, 周飞, 等. 基于比例积分-降阶谐振调节器的并网逆变器不平衡控制［J］. 中国电机工程学报, 2013, 33(19): 84-92. ZHAO Xin, JIN Xinmin, ZHOU Fei, et al. Unba-lanced control of grid-connected inverters based on proportion integral and reduced order resonant controllers［J］. Proceedings of the CSEE, 2013, 33(19): 84-92. ［12］易皓, 卓放, 翟灏. 基于矢量谐振调节器的有源电力滤波器网侧电流检测控制方法研究［J］. 电工技术学报, 2015, 30(7): 72-79. YI Hao, ZHUO Fang, ZHAI Hao. Research on source current detection type APF control scheme based on vector resonant regulator［J］. Transactions of China Electrotechnical Society, 2015, 30(7): 72-79. ［13］朱荣伍, 伍小杰, 杨艳, 等. 采用比例谐振调节器的单相电压型 PWM 整流器［J］. 高电压技术, 2010, 36(8): 2095-2100. ZHU Rongwu, WU Xiaojie, YANG Yan, et al. Single-phase voltage-source PWM rectifier using pro-portion resonant controller［J］. High Voltage Engi-neering, 2010, 36(8): 2095-2100. ［14］龙熹, 陈敏, 彭国荣, 等.基于比例多谐振控制的直驱永磁风力发电系统谐波抑制研究［J］.可再生能源, 2016, 34(9): 1314-1319. LONG Xi, CHEN Min, PENG Guorong, et al. Research on harmonic suppression of D-PMSG wind power generation system based on proportional-multi resonant controller［J］. Renewable Energy Resources, 2016, 34(9): 1314-1319. ［15］刘斌, 谢积锦, 李俊, 等.基于自适应比例谐振的新型并网电流控制策略［J］.电工技术学报, 2013, 28(9): 186-195. LIU Bin, XIE Jijin, LI Jun, et al. Novel grid-connected current control strategies based on self-adaptive proportional-resonant［J］. Transactions of China Electrotechnical Society, 2013, 28(9): 186-195. ［16］王剑, 郑琼林, 高吉磊. 基于根轨迹法的单相 PWM 整流器比例-谐振电流调节器设计［J］. 电工技术学报, 2012, 27(9): 251-256. WANG Jian, ZHENG Qionglin, GAO Jilei. Design of current proportional-resonant regulator for single-phase PWM rectifier based on root-locus method［J］. Transactions of China Electrotechnical Society, 2012, 27(9): 251-256.