摘要
模块化多电平变流器(mudular multilevel converter,MMC)在主电路结构中可以有效提高光伏并网系统的光能利用率。提出了一种光伏电站直流并网方案,通过大功率高变比的有源箝位Boost全桥隔离变换器串联升压,然后经MMC实现光伏高压直流并网。针对光伏并网后交流侧电压的稳定性,提出了基于电压前馈的双闭环控制策略。在MATLAB/Simulink中搭建串联型光伏电站经MMC并网模型,并应用基于电压前馈的双闭环控制策略,验证所提拓扑方案的正确性以及控制策略的可行性。结果表明,控制策略可以在发生三相短路故障时及时补偿电压,提高交流系统侧的可靠性。
The modular multilevel converter(MMC)can effectively improve the light energy utilization rate of the photovoltaic grid-connected system in the main circuit structure.A DC grid-connected solution for photovoltaic power plants was proposed.A high-power,high-transformation ratio active clamp boost full-bridge isolation converter(BFBIC)was used to implement series boost,and then the photovoltaic high-voltage DC grid-connection was realized by MMC.In addition,for the stability of the AC side voltage after photovoltaic grid-connection,a double closed-loop control strategy based on voltage feed forward was put forward.A series photovoltaic power station was built in MATLAB/Simulink,the MMC grid-connected model was used then,and a double closed-loop control strategy based on voltage feed forward was applied finally to verify the correctness of the proposed topology and the feasibility of the control strategy.The simulation verification results show that the control strategy can compensate the voltage in time when a three-phase short-circuit fault occurs,and improve the reliability of the AC system.
作者
庞宇琦
马刚
刘勋宇
徐啸天
张新源
吕捷
Pang Yuqi;Ma Gang;Liu Xunyu;Xu Xiaotian;Zhang Xinyuan;Lyu Jie(School of Electrical and Automation Engineering,Nanjing Normal University,Nanjing Jiangsu 210046,China)
出处
《电气自动化》
2022年第2期18-20,24,共4页
Electrical Automation
基金
国家自然科学基金项目(51607093)。
关键词
模块化多电平变流器
光伏并网
三相短路
电压补偿
闭环控制
modular multilevel converter(MMC)
photovoltaic grid-connection
three-phase short circuit
voltage compensation
closed-loop control
