Research And Application Of The High Voltage Ride Through Technologies Of PMSG

The “centralized access and high voltage transmission” characteristics of China’s wind power lead the frequent voltage fluctuations in the wind power centralized areas and the difficulties in reactive voltage operation and adjustment, in severe cases it can lead to large-scale wind turbines off the net and resulting in adverse impact on the security and stability of the grid. Based on the analysis of the all previous wind turbines tripping-off events, it can be found that the grid voltage fault generally has a "low voltage + high voltage" or "a single high voltage" feature. With the gradual completion of wind power units low voltage ride through capability transformation, the high voltage ride through had become an important constraints that affecting the grid stability. And the research on wind turbine high voltage ride through technology had increasingly become a hot research for scholars.With the rapid development of power electronic technology, direct drive wind turbine with its high reliability and low maintenance cost advantages had become the main model of wind turbine operation. Therefore, it’s necessary to research the high voltage ride through technologies of PMSG.Based on the analysis of the mathematical model of PMSG, the simulation model of PMSG is built on the PSCAD simulation platform. The effect of different grid voltage swells indicators on the operation of the PMSG can be recognized by the analysis of the wind turbine tripping-off events and the comparison of the simulation results of the PMSG model under the ideal grid voltage and the grid voltage swell.Finally, the HVRT control strategy of PMSG based on reactive power support was put forward based on the analysis of the inconsistent power flow among the wind turbine. Furthermore, the availability of the strategy was verified by the results of both the simulation and field test.The HVRT capacity of PMSG can be effectively improved through the adoption of the HVRT control strategy of PMSG, the research achievements have valuable important theoretical and practical significance.