适用于故障特性分析的锂离子电池储能电磁暂态建模方法

Electromagnetic Transient Modeling Method of Lithium-ion Battery Energy Storage System for Fault Characteristic Analysis

为促进新能源的消纳利用,锂离子电池储能系统(LiBESS)在电网中得到了广泛应用,进一步导致电网故障特征更加复杂。为此,提出一种LiBESS电磁暂态建模方法。在分析故障特征的基础上,建立了功率变流器系统(PCS)模型和兼顾电池外特性、荷电状态的锂离子电池模型。PCS控制策略引入了故障穿越控制环和负序控制环,实现了故障穿越并消除了直流母线电压波动。此外,通过机理分析和仿真验证明确了LiBESS在不同充放电模式下的故障特性差异。最后,基于PSCAD/EMTDC的电磁暂态仿真和基于实时数字仿真器的硬件在环测试验证了所提建模方法的有效性。

To promote the accommodation and utilization of the renewable energy,the lithium-ion battery energy storage system(LiBESS)has been widely used in power systems,resulting in more complicated fault characteristics.An electromagnetic transient modeling method for LiBESS is proposed.Based on the analysis of the fault characteristics,the power converter system(PCS)and the lithium-ion battery taking the external characteristics and the state of charge(SOC)into account are established.The fault ride-through control loop and negative-sequence control loop are introduced into the control strategy of PCS to realize the fault ride-through and eliminate the fluctuation of DC bus voltage.In addition,the difference in fault characteristics of LiBESS under different charging and discharging modes are analyzed through mechanism analysis and simulation verification.Finally,accuracy of the proposed modeling method is verified based on the electromagnetic transient simulation in PSCAD/EMTDC and hardware-in-loop test in RTDS.