基于VSG技术的光伏-储能并网系统协调控制策略

A Coordinated Control Strategy for PV-Energy Storage Grid-Connected Systems Based on VSG Technology

中文关键词:光伏发电  储能装置  虚拟同步发电机  协调控制

keywords:photovoltaic power generation  energy storage device  virtual synchronous generator  coordinated control

中文摘要:针对光伏-虚拟同步发电机技术（photovoltaic virtual synchronous generator，PV-VSG）的现有问题，围绕共直流母线型PV-VSG建立了数学模型，并提出相应的协调控制策略。该策略利用双向DC/DC变流器实现最大功率点跟踪（maximum power point tracking，MPPT）算法，光伏逆变器则负责实现虚拟同步算法，使系统各部分功能清晰明确，降低了对协调控制的要求。通过在并网运行工况、调频运行工况和光照突降运行工况3种工况进行仿真，验证了所提方法的有效性。实验结果表明，与现有的控制策略相比，所提方法简化了控制策略，能够有效抑制光伏逆变器输出功率波动。

Abstract:To address the existing issues of photovoltaic-virtual synchronous generator （PV-VSG） technology，a mathematical model is established for the PV-VSG with a common DC bus，and a corresponding coordinated control strategy is proposed. This strategy employs bidirectional DC/DC converters to implement the maximum power point tracking （MPPT） algorithm，while the PV inverter is responsible for executing the virtual synchronous algorithm. This design clarifies the functions of each system component and lowers the demands on coordinated control. Simulations are conducted under three scenarios： grid-connected operation，frequency regulation operation，and sudden illumination drop. The results verify the effectiveness of the proposed method. Compared with existing control strategies，the proposed approach simplifies the control strategy and can effectively suppress the output power fluctuations of the PV inverter.