Requirement Analysis of Wind Turbine High Voltage Ride-through Capability Detection and Simulation

Abstract

With the number of wind farms connected to the power system increasing rapidly, the impact of wind power generation system on power grid system stability is becoming increasingly prominent. Especially when the power grid has transient fault, there will be problems such as reverse power flow, large-area power failure of wind farm and so on. This will directly lead to the power system instability and seriously affect the power grid security and stability. Especially in the stage of voltage recovery after the fault is eliminated, the low-voltage fault of the power grid might lead to a sharp rise in the voltage of power grid and overvoltage on the high-voltage line connected to the power grid with wind farm, resulting in the disconnection of the wind power grid connected system. However, China’s current standards do not specify the high-voltage crossing of wind power grid connected system, especially the high-voltage crossing detection device, detection method and detection procedure. Therefore, it is urgent to study the detection technology of wind power high voltage crossing and put forward the detection method. There are many reasons for high-voltage power grid fault, and the interaction between power grid and inverter is more complex in high-voltage fault. If the type test method is used to simulate various high-voltage fault conditions in power system and carry out the test and study on the HVRT( high voltage ride through) performance of wind turbine, the human and material cost is huge and there are many potential safety hazards. At the same time, the grid connection performance of wind turbines are largely related to the control strategy of the controller. Therefore, the semi physical simulation method can be used to research the HVRT detection technology of wind turbine. This can effectively avoid the safety problem of large current and high voltage in the primary circuit, and realize the physical connection between the real controller and the flexible high voltage fault platform model through hardware in the loop simulation. It can simulate the wind turbine capability of high-voltage ride through under various high-voltage fault conditions. It not only has low test cost, but also can deeply study the interaction between power grid and power grid.