基于二阶滑模控制的虚拟发电厂分层协同无功电压控制策略

Hierarchical cooperative reactive power and voltage control strategy of virtual power plant based on second-order sliding film control

虚拟发电厂作为分布式发电并网运行和集成管理的关键技术,其电压稳定性是一门重要课题。针对含分布式发电并网的虚拟发电厂电压控制问题,文章基于二阶滑模控制,建立了虚拟发电厂分层协同无功电压控制策略。其中:上层控制模块将电压波动期间需要补偿的无功功率采用下垂特性分配给系统中各个可参与调节DG的逆变器;下层控制模块首先建立虚拟发电厂无功电压的非线性状态方程,然后确定无功电压控制的滑模面,最后得到二阶滑模控制的等效控制策略。仿真算例表明,根据所建立的模型,虚拟发电厂能够有效应对电压波动,维持系统的电压稳定性。

As the key technology of grid connected operation and integrated management of distributed generation,the voltage stability of virtual power plant has been an important subject.Aiming at the voltage control problem of virtual power plant with distributed generation connected,a hierarchical coordinated reactive voltage control strategy was established based on the second-order sliding control.Firstly,the upper control module distributes the reactive power that needs to be compensated during the voltage fluctuation to each inverter which can participate in the regulation of DG in the system,and uses the droop characteristic to distribute.The lower level model firstly established the nonlinear state equation of reactive voltage in virtual power plant,then determines the sliding surface of reactive voltage control,and finally obtains the equivalent control strategy of the second-order sliding mode control.