基于边际发电成本的联络线交换功率两阶段迭代优化方法

Two-stage iterative method to optimize tie-line exchange power based on marginal power generation cost

为充分利用联络线功率输送能力,降低电网总体运行成本,提出一种基于边际发电成本的联络线交换功率两阶段迭代优化方法。从各区域电网初始机组组合方案与各联络线初始交换功率出发,分两阶段对联络线交换功率进行迭代优化。首先,在不改变机组开机方式的前提下,基于各区域电网的边际发电成本对联络线交换功率进行第一阶段迭代优化。接着,对区域电网中出力连续等于最小技术出力且发电成本最高的边际机组进行关机操作,在此基础上进行第二阶段迭代优化。该方法与电网实际调度过程联系紧密,且仅需各区域电网提供边际机组的运行信息,保护了各区域电网的数据隐私。最后,基于3个区域电网和3条联络线的仿真实验验证了所提模型和方法的有效性。

To fully use power transmission capacities of tie-lines and reduce the total operating costs of the power grid,a two-stage iterative optimization method is proposed to optimize exchange power of the tie-lines based on marginal power generation cost.The method iteratively optimizes exchange power of the tie-lines by successive two stages,starting from initial results of Unit Commitment(UC)of each regional power grid and initial exchange power of each tie-line.In the first stage,the exchange power of the tie-lines is optimized based on the marginal power generation costs of each regional power grid without changing the results of the UC.Then,the unit whose output power is continuously equal to the minimum technical outputs and with the highest marginal cost is turned off.After that,the second-stage iterative optimization of exchange power of the tie-lines is executed.The method can be easily applied to engineering practice because it is closely related to the actual dispatching process of the power grid,and only needs the regional power grid to provide the information of the marginal unit operation.This protects the data privacy of each regional power grid.Finally,a simulation is performed based on a case system of three regional grids and three tie-lines,and the simulation results verify the method.