含变速恒频风电机组的电网运行特性仿真

风力发电机组的输出功率会随着风速变化而变化，对系统的稳定性和可靠性造成一定的影响。本文通过Simulink模块来搭建风力发电机组各部件系统的仿真模型，并将搭建的风力发电机模型与电网模型进行并网运行仿真。研究了不同风速下风力发电机组并网对电网的影响，以及不同故障下风力发电机对电网运行稳定性的影响。结果表明：当风力发电机组在高风速和低风速下运行时，风力发电机组输出的无功功率、有功功率都远小于在额定风速下的，从而造成不小的功率缺额，对电网系统电压幅值的稳定和维持整个电网系统频率的恒定有重要影响。通过对比发现，对稳定性影响程度最大的是三相短路故障，其次的是系统发生两相接地短路故障，接着是发生两相相间短路故障，其中故障后对电力系统稳定性影响程度最小的是发生单相接地短路故障。

Simulation Research on Grid Operation Characteristics of Wind Turbines with Variable Speed and Constant Frequency

The output power of the wind turbine will change with the wind speed, which will affect the stability and reliability of the system. This paper uses Simulink modules to build simulation models of various components of the wind turbines, and builds the wind turbine model with the power grid. The model is connected to the grid for simulation. The influence of wind turbines connected to the grid on the grid under different wind speeds and the influence of wind turbines on the stability of the grid under different faults are studied. The results show that: when the wind turbine is operating at high wind speed and low wind speed, the reactive power and active power output by the wind turbine generator are far less than those at the rated wind speed, resulting in a large power shortage, which affects the voltage amplitude of the grid system. The stability of the value and maintaining the constant frequency of the entire grid system have an important impact. Through comparison, it is found that three-phase short-circuit faults have the greatest impact on stability, followed by two-phase-to-ground short-circuit faults in the system, and then two-phase-to-phase short-circuit faults. Among them, the least impact on the stability of the power system after the fault is A single-phase grounding short-circuit fault has occurred.