风光互补发电系统并网逆变器控制策略研究

Research on Control Strategy of Grid-connected Inverter in Wind-solar Hybrid Power Generation System

为了提高风光互补发电系统并网后的稳定性,针对其并网逆变器,提出一种分段控制改进型双闭环比例积分控制策略,即根据风光的强弱分段采用风机转速外环-风机电流内环、Boost升压电路直流电压外环-并网电流内环的控制结构,以此来消弱对电网频率和幅值的影响。首先分析风力发电、光伏发电和蓄电池的数学模型,然后构建互补发电系统并提出控制策略,最后通过仿真软件进行仿真验证。仿真结果表明,所提控制策略可有效实现风光互补发电系统并网后不同时段的稳定运行,减小并网电流的波动,维持电压电流的稳定,增加电网消纳新能源的能力。

In order to improve the stability of the wind-solar hybrid power generation system after being connected to the grid,for its grid-connected inverter,a segmented control improved double closed-loop proportional integral control strategy was proposed.It was that in line with strong and weak sections,the control structure of wind turbine speed outer loop-wind turbine current inner loop,boost circuit DC voltage outer loop-grid current inner loop was used to weaken the influence on the grid frequency and amplitude.Firstly,the mathematical models of wind power generation,photovoltaic power generation,and storage batteries were analyzed,and then a complementary power generation system was constructed and the control strategy was proposed.Finally,a simulation software wasutilized for simulation verification.The simulation results show that the proposed control strategy can effectively realize the stable operation of the wind and solar hybrid power generation system in different periods after the grid is connected,reduce the fluctuation of the grid-connected current,maintain the stability of the voltage and current,and increase the ability of the grid to absorb new energy.