风电火电打捆送出时的输电容量优化方法

A method to optimize transmission capacity of wind power in combination with thermal power

风电火电打捆送出是实现大容量风电远距离送出的一种比较经济可行的方法。针对现有的可再生能源政策以及火电机组的实际运行特性,提出了风电优先同时考虑火电机组最小技术出力的风电火电打捆送出策略。利用风电场群出力持续曲线来描述风电场群的年出力特性,基于此曲线以及风电火电送出策略给出了确定输电容量下的风电与火电年实际可送出电量以及阻塞电量的计算方法。在综合考虑由于阻塞电量导致的损失,打捆送出时对火电的不利影响以及输电线路建设成本的基础上,给出了输电容量的优化方法。算例分析表明该算法可以在优化输电成本的同时,最大程度地减少风电火电打捆送出时各方面的不利影响。

It is an economic way to transmit large capacity of wind power in combination with thermal power to far away. Considering the current renewable energy policy and the operation characteristics of thermal plant, this paper proposes a strategy to transmit wind power in combination with thermal power, which takes both wind power priority and minimum technological output of thermal into consideration. The annual output characteristic of wind farms is described by the wind power duration curve, based on which the annual transmitted power and the congestion loss due to transmission limitation are calculated. The optimal transmission capacity is calculated by making a balance between congestion loss and the cost of transmission line, also, the negative effect on thermal power while transmitting power in combination with wind power is considered. The result shows that the proposed method can minimize the transmission cost; also the negative effect of both wind power and thermal power can be relieved.