Integration of Wind Farm into Gansu Power Grid and its Operation

Jiuquan area is located in Hexi Corridor which is in the Silk Road, Gansu Province, China. In recent years, wind power penetration into the grid has increased rapidly with abundant wind resources in Jiuquan, according to the policy of the Chinese government to "establish a 'Hexi Wind Power Corridor' and rebuild another Western 'Terrestrial Three Gorges Dam'". By the end of 2008, the total installed capacity of wind power in Jiuquan has reached 508.6 MW, which is about 3.34% of total electric power generation of Gansu province. The wind farms are connected to 110 kV transmission network or above in Jiuquan, the studies of their impacts on the grid, in particular, the grid operation are becoming serious and urgent. Jiuquan is far away from the load center with a weak grid configuration, therefore issues such as transmission line overloading, local grid voltage fluctuation, and transient stability limitation are looming with large scale wind power integration. The power system dispatch and operation are influenced by the intermittent nature of the wind power, which should be regulated by the system reserves. This paper discusses the recent integration of wind power into the grid with a focus on the impact on the Gansu power grid operation. The paper also presents the measures to deal with these issues.