引用本文: | 朱晓荣,刘世鹏,张海宁,等.不平衡电网电压下光伏并网逆变器滑模直接电压/功率控制策略[J].电力系统保护与控制,2016,44(23):133-140.[点击复制] |
ZHU Xiaorong,LIU Shipeng,ZHANG Haining,et al.Sliding mode control based direct voltage/power control strategy for PV grid connected inverter under unbalanced grid voltage[J].Power System Protection and Control,2016,44(23):133-140[点击复制] |
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摘要: |
不平衡电网电压下,光伏并网逆变器的输出功率和输出电流都将产生波动,给电力系统的稳定运行造成不利影响。根据光伏并网系统的数学模型,提出了光伏并网逆变器基于滑模控制的直接电压/功率控制策略。该控制策略可在电网电压不平衡时有效抑制并网逆变器输出有功功率和无功功率的波动。根据光伏并网逆变器输出功率和正、负序电流的关系,提出了以消除负序电流为控制目标的改进控制策略。此外,为提高系统的运行性能,提出了功率电流协调控制策略。最后,对所提出的控制策略进行了仿真分析,仿真结果验证了所提出控制策略的有效性。 |
关键词: 光伏并网逆变器 不平衡电网电压 滑模控制 直接电压/功率控制 |
DOI:10.7667/PSPC151977 |
投稿时间:2015-11-11修订日期:2016-03-07 |
基金项目:青海省光伏发电并网技术重点实验室资助项目(2014-Z-Y34A) |
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Sliding mode control based direct voltage/power control strategy for PV grid connected inverter under unbalanced grid voltage |
ZHU Xiaorong,LIU Shipeng,ZHANG Haining,WANG Dongfang,LI Chunlai |
(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University, Baoding 071003, China;Qinghai Province Key Laboratory of Photovoltaic Grid Connected Power Generation Technology, Xining 810000, China) |
Abstract: |
Under unbalanced grid voltage, second order pulsation component will appear in the output power and the output current of the PV grid connected inverter, which will affect the stable operation of the power system. Based on the mathematical model of PV grid connected system, this paper proposes a direct voltage/power control strategy based on sliding mode control (SMC) for the PV grid connected inverter. When the grid voltage is unbalanced, the control strategy can effectively suppress the power oscillation in the active and reactive power. According to the relationship between the output power and the positive/negative sequence current of the PV grid connected inverter, an improved control strategy is proposed to eliminate the negative sequence current. In addition, a power/current coordinated control strategy is proposed to improve the operating performance of the PV system. Finally, simulation analysis is carried out, and the results verify the effectiveness of the proposed control strategy. |
Key words: PV grid connected inverter unbalanced grid voltage sliding mode control direct voltage/power control |