Research On Black-Start Strategy Of Wind-Power System With Integrated Energy Storage

With the rapid development of power system and new energy technology,the blackout risk of grid has increased significantly,therefore the black start scheme is of more importance than before.As the effectiveness of the black start scheme is based on choice and equipment of black start resources,it will improve the black start capability of grid together with the realization of high adaption of wind power if wind park could serve as the black start resource.In this paper we first establish the black start unit(BSU)which combines the wind park,energy storage system and gas turbine together through coordinated control strategy.Then the black start experiment simulation is performed in the IEEE39-bus system on the PSCAD/EMTDC platform to check the availability of BSU,so that the effectiveness of the research is confirmed.First,the mathematical model of doubly fed wind turbine is analyzed by setting up equivalent models on PSCAD/EMTDC platform.To avoid the strong current surge caused by wind park and gas turbine when integrated to grid and to realize the safety and steady integration,the idle load integration control strategy of wind turbine is studied and the rationality and correctness of the models above are ensured by simulation,which is the basis for gas turbine to crank the wind turbine.Then the mathematical model of gas turbine,energy storage system and the relative control strategy are studied by setting up models on PSCAD/EMTDC platform.The coordinated control scheme of BSU is settled,in which the specific turbine offering full range supporting response to frequency disturbance of isolated BSU system is figured out and the fluctuation range of the energy storage systems is decided out of the power surge the BSU system could bear.After that the energy storage system control strategy is made up,in which the gas turbine provides cranking power in the BSU system and energy storage station balances the fluctuation of wind park output.The practicability of wind-fuel complementary power generation system and BSU serving as black start resource and the rationality of energy storage system are proved by simulation.Finally,the black start path recovery scheme is brought up according to the shortest path method of the front K and the technical verification to follow-up recovery progress of BSU-contained system is performed mainly aimed at the over-voltage problem of transmissions,as the system voltage and frequency safety when load of plant recovers has been checked.The results confirm that the system could serve as the black start resource.The black start simulation experiment in IEEE39-bus system confirm that the BSU system could crank the auxiliary machine of generators in power plant and the local vital loads independently.