适用于复杂负载条件下的光伏独立构网控制

Control Strategy for Grid Forming Photovoltaic Network Under Complex Load Conditions

新能源光伏发电系统具备独立构网与电压频率支撑能力是未来以新能源为主体的新型电力系统重要技术需求。考虑负载具有不平衡、非线性、时变等特点,针对复杂负载条件下的不平衡负载问题,提出一种基于新型谐振控制器的新能源光伏独立构网控制策略,其中电流内环采用电感电流比例控制器,电压外环采用新型谐振控制器。给出了电流环配置方法,提出了近似电感电流反馈法,分析了基于新型谐振控制器的电压环设计方法。最后通过原理样机实验表明所提方法实现了新能源光伏逆变器在独立构网条件下对不平衡负载的良好控制,具有高动态响应特性,有很好的工程实用参考价值。

New energy photovoltaic power generation system with independent network and voltage and frequency support capacity is an important technical requirement of the new power system with new energy as the main body in the future.Considering the unbalanced,nonlinear and time-varying characteristics of the load,a new energy photovoltaic independent network control strategy based on a novel resonance controller is proposed for the unbalanced load under complex load conditions,in which the inner current loop adopts an inductive current proportional controller and the outer voltage loop adopts a new resonance controller.The current loop configuration method is presented,the approximate inductive current feedback method is proposed,and the voltage loop design method based on the new resonant controller is analyzed.Finally,the theoretical prototype experiment shows that the proposed method achieves good control of unbalanced load under the condition of independent network,and has high dynamic response characteristics,which has good engineering practical reference value.