构网型光伏自同步电压源控制策略研究

Research on the Control Strategies of Grid-forming Photovoltaic Self-synchronizingg Voltage Source

为提升光伏发电并网适应性以及在极弱电网工况下的频率电压支撑能力,提出并研究了一种构网型光伏自同步电压源控制策略,阐述了其基本工作原理,给出了其关键控制方程、工作模式及切换逻辑。所提构网型光伏自同步电压源逆变器不仅可向电网提供必要的频率及电压支撑,并可在电网发生故障时,具备独立向关键负载供电的构网能力。最后通过搭建的500 kW构网型光伏自同步电压源硬件在环实验平台充分验证了所提控制策略的有效性和正确性。

In order to improve the grid-connected adaptability of the photovoltaic power generation system and the frequency and voltage support capability under extremely weak grid conditions,a control strategies of grid-forming photovoltaic self-synchronizing voltage source is proposed and studied.The basic working principle is expounded,and the key control equation,working modes and switching logic are given.The proposed grid-forming photovoltaic self-synchronizing voltage source inverter can not only provide necessary frequency and voltage support to the grid,but also have the grid-forming ability to independently supply power to key loads when the grid fails.Finally,the validity and correctness of the proposed control strategy are fully verified by the hardware-in-the-loop experiment platform of 500 kW grid-forming photovoltaic self-synchronizing voltage source.