摘要
针对两级并网光伏系统在光伏阵列功率波动时难以兼顾最大功率点跟踪和母线电压稳定控制的问题,提出一种应用于单相两级并网光伏系统的混合控制算法。该算法利用交错Boost变流器中的一只全控型器件对最大功率点进行快速跟踪,而另一只全控型器件对光伏系统的直流母线电压进行稳定控制,从而同时实现最大功率跟踪和直流母线电压稳定的控制。理论分析和仿真结果表明,所提出的混合控制策略在稳态时能使光伏系统工作在最大功率点处;当输入功率发生剧烈变化时,光伏系统的直流母线电压波动较小,有效地避免直流母线电压在功率波动时的电压冲击,提高了直流母线电容的使用寿命。
Aimed at the problem that a two-stage grid-connected photovoltaic(PV)system is difficult to realize maxi⁃mum power point tracking(MPPT)and bus voltage control at the same time under power fluctuations of a PV array,a kind of hybrid control algorithm is proposed,which can be applied to a single-phase two-stage grid-connected PV system.This algorithm adopts one dependent controllable power device in an interleaved Boost converter to fast track the maximum power point,and uses another one to realize the stable control of DC-link voltage for the PV system.As a re⁃sult,MPPT and DC-link voltage regulation can be realized at the same time.Theoretical and simulation results show that the PV system can work at the maximum power point in a stable state under the proposed hybrid control strategy,and the fluctuations of DC-link voltage can be reduced under significant changes in input power,indicating that this al⁃gorithm can effectively avoid the voltage impulse of DC-link voltage under power fluctuations and improve the lifetime of the DC-link capacitor.
作者
张爽
张迪
薛飞
徐恒山
ZHANG Shuang;ZHANG Di;XUE Fei;XU Hengshan(Electric Power Research Institute,State Grid Ningxia Electric Power Co.,Ltd,Yinchuan 750001,China;College of Electrical Engineering&New Energy,China Three Gorges University,Yichang 443002,China)
出处
《电力系统及其自动化学报》
CSCD
北大核心
2022年第10期89-96,共8页
Proceedings of the CSU-EPSA
基金
宁夏自然科学基金资助项目(2020A1176)。
关键词
光伏系统
直流变换
混合控制策略
功率波动
直流母线电压
photovoltaic(PV)system
DC conversion
hybrid control strategy
power fluctuation
DC-link voltage
