中压兆瓦级电网模拟器研究

Research on Medium Voltage Megawatt Power Grid Simulator

光伏电站、风电机组及储能电站等集中式并网发电系统接入电网的电压等级主要为中压10 kV和35 kV,且功率多为兆瓦级。为测试这些兆瓦级、中压直挂式并网发电系统的电网适应性能力,设计了一种输入并联输出串联(IPOS)的电网模拟器拓扑结构,通过载波移相脉宽调制(CPS-PWM)技术提高了高压侧输出的电能质量;介绍并分析了复合控制策略下模拟中压电网的电压跌落特性以及谐波控制策略。在仿真基础上搭建35 kV/3 MW测试平台,实验结果证明该结构拓扑的可靠性及控制策略的可行性和正确性。

The voltage levels of centralized grid-connected power generation systems such as photovoltaic power plants,wind turbines and energy storage power plants are mainly 10 kV and 35 kV,and the power is mostly megawatt level.In order to test the grid adaptability of these megawatt-level,medium voltage direct-connected power generation systems,a power grid simulator topology with input parallel output series(IPOS)is designd,and the power quality of high voltage side output by carrier phase shift pulse width modulation(CPS-PWM)technology is improved.The voltage drop characteristics and harmonic control strategy of the simulated medium voltage grid under the composite control strategy are introduced and analyzed.Based on the simulation,a 35 kV/3 MW test platform is built.The experimental results prove the reliability of the structure topology and the feasibility and correctness of the control strategy.