光储发电系统的虚拟转动惯量控制

Virtual rotational inertia control of PV generation system with energy storage devices

在深入研究光储发电系统控制策略的基础上,阐述蓄电池虚拟转动惯量的概念,分析在频率动态变化过程中蓄电池的电池储能与机械动能之间的能量转换关系,并提出基于光储发电系统的虚拟惯性控制策略。该控制策略通过检测系统频率的变化与蓄电池荷电状态,调节蓄电池的荷电状态变化率与充放电电流的速率,从而短时调节蓄电池储备能量为系统提供惯性支持。通过光伏装机比重约为30%的仿真系统,验证该控制策略在系统出现功率不平衡后,能够利用蓄电池的虚拟惯量快速响应系统频率变化,从而提高了系统的频率稳定性。

On the basis of the control strategy for PV（Photo Voltaic） generation systems,the concept of virtual inertia of battery is defined. The energy conversion relationship between the battery energy and the mechanical kinetic energy is analyzed,and the virtual inertia control method of PV generation system with energy storage devices is proposed. The proposed strategy could regulate the rate of SOC（State Of Charge）and the battery current according to the frequency deviation and the SOC of battery. The battery reserve energy can be adjusted in a short time to provide the inertial support to the system. A simulation system,in which the installed capacity of PV is around 30% of the total installed power generators,is designed to validate the effectiveness of the proposed control strategy. Simulative results indicate that the proposed virtual inertia control of battery provides rapid response to the frequency fluctuation,effectively improving the frequency stability of the power system.