The photovoltaic plants controlled by self-standby can provide frequency regulation capability for the power grid.But the existing self-standby control is difficult to evaluate the maximum power and and the economy is required to be quantified.Additionally,it can not provide virtual inertia.The effect of frequency regulation response of photovoltaic plants needs to be improved.To address this problem,this paper proposes a virtual synchronous FR control strategy for PV power plants with adjustable self-standby.Firstly,based on the P-V operation characteristics of PV,a PV maximum power estimation strategy is proposed,as well as a variable step voltage control strategy to achieve PV self-standby control.Second,based on the virtual synchronous generator control strategy and the photovoltaic plant architecture,the frequency feedback control loop is introduced.And the photovoltaic self-standby adjustable control strategy is proposed,supporting the frequency stability of the power grid in the form of virtual inertia.In addition,energy storages connected in parallel on the DC side of the photovoltaic ensure the stability of the DC bus voltage during the dynamic adjustment of the photovoltaic operating point with the self-backup rate.The influence of the error of the maximum power estimation algorithm on the virtual synchronous frequency control strategy is further analyzed.And the influence of the change of virtual synchronous control parameters on the frequency modulation effect is discussed.Finally,Simulink simulation results verify the effectiveness of the proposed control strategy and provide theoretical support for the grid-connected regulation of PV.
关键词
光伏电站/最大功率估算/自备用/虚拟同步控制/调频
Key words
photovoltaic power plants/maximum power estimation/self-standby/virtual synchronous control/frequency regulation
维普
万方数据