| With the rapid development of AC-DC networking, the superiority of AC-DC for long-distance transportion of wind power is apparent increasingly. The wind farm scale is larger and larger, and with the restriction of AC transmission technology and electricity market absorption capacity, the AC-DC systems long-distance transport has become an important way to send large-scale wind power to load centers. Nowadays how to use the AC-DC system control measures to improve the delivery capacity of wind power is a very important problem.Firstly, paper studies the operating characteristics of HVDC and AC transmission and their superiorities are proposed respectively. On this basis, the effects of AC and DC are studied, including the impact of HVDC control on AC system and the effect of converter station reactive power compensation on AC voltage. The operating characteristics of wind power are also analyzed, including the active power output characteristics of wind power and the reactive power and voltage characteristics. The influence of AC and DC transmission on improving wind power transmission capacity is discussed. Based on the advantages of AC-DC, AC-DC transmission can improve the long-distance transmission capacity of wind power more than AC transmission, and the present problem in large-scale long-range wind power transmission by AC-DC power system is proposed. Due to the above issue, AC-DC coordinated control method and mechanism are analyzed. Eventually a plan of AC-DC outgoing coordinated control strategy for improving the ability of wind power transmission is proposed. The policy is applied to Hexi grid, and the simulation results show the effectiveness of the strategy to improve the delivery capacity of wind power. |
