Reactive Power Control Method Based On Improve Voltage Qualification Rate Of Distributed Wind Farm

Distributed wind farm mean that wind farm direct access to rural power or low-voltagegrid, compared with the conventional large-scale centralized wind farm, which is a way toavoid a wide range of "abandoning the wind","left power", and so on,while distributed windpower can be fully integrated with the existing power system, it can form a highly efficientand flexible power supply system to improve the reliability of the grid. But most distributedwind farm reactive power and voltage control rely on reactive power compensation equipment,which did not make full use of the wind turbine relying on converter reactive power.In order toimprove distributed wind farm control point voltage qualification rate, in coordination reactivepower and voltage control, the paper made the following research:First, dynamic model of wind turbine research and use PSCAD simulation of wind speed,wind speed simulation model consists of four basic components, through the four basiccomponents simulation and get the synthetic wind speed finally. Based wind farmpower-speed characteristics, discussing the principles of maximum wind energy capture.Based on the wind power system mainstream models, the paper grasp the power principle,establish dynamic mathematical model through PSCAD simulation software.Secondly, discuss the converter of double-fed wind turbine control reactive outputcapacity and the distributed wind farm reactive power voltage control method of reactive PIlayer and reactive power distribution layer. Understand monitor points voltage setting methodsand computational methods to the voltage qualification rate of distributed wind farm.Finally, the paper research the influence of the control point voltage qualification ratecaused by each reactive power compensation device. Compare the advantages anddisadvantages of each device on reactive power-voltage regulation. Practical engineering isthat the PSCAD simulation for the North Zhen Yang distributed wind farms. On the basis ofthe proposed wind farm loss minimum objective function that contain generators, collectorlines and box-type transformers. Use equal incremental method find the optimal value of theobjective function, according to the optimal value can minimize the network loss of distributedwind farm, the actual engineering verification show that the reactive power-voltage coordinatecontrol scheme not only improve the control point voltage qualification rate, but also has apositive effect on the wind farm economy.