电化学储能电站NPC三电平变流器仿真建模研究

利用仿真软件及实验设备对中点钳位型（NPC）三电平储能变流器进行研究。首先建立1500 V高压直流储能系统,其能量密度、功率密度、系统循环效率较高,且成本和占地面积较低,正逐渐成为主流;然后建立单台NPC三电平变流器（PCS）模型,结合储能系统、滤波电路、变压器等形成电站基本结构,并将多台设备并联建立储能电站模型;最后通过dq坐标系全解耦控制策略实现对PCS输出功率的控制,从而实现与电网的功率互动。仿真和实验结果表明,储能电站可迅速切换充、放电工作状态,并准确跟踪目标功率,输出波形良好、畸变率低的并网电压,从而实现对电网的调节。

RESEARCH ON SIMULATION MODELING OF NPC THREE-LEVEL CONVERTER IN ELECTROCHEMICAL BATTERY ENERGY STORAGE SYSTEM

The neutral point clamped （NPC） three-level energy storage converter is studied by using simulation software and experimental equipment. Firstly, 1500 V HVDC energy storage system is established, which has high energy density, high power density, high system cycle efficiency, low cost and less floor area, and is gradually becoming the mainstream; Then, the model of single NPC three-level power conversion system （PCS） is established. Combined with the energy storage system, filter circuit and transformer, the basic structure of the power station is formed, and the model of energy storage power station is established by connecting multiple equipment in parallel; Finally, the full decoupling control strategy in dq coordinate system is used to control the output power of PCS, so as to realize the power interaction with the power grid. The simulation and experimental results show that the battery energy storage station can quickly switch the charging and discharging working states, accurately track the target power, and output the grid connected voltage with good waveform and low distortion rate, so as to realize the regulation of the power grid.