考虑电网安全约束条件的机组组合新方法

Novel approach to unit commitment with security constraints

为在电力市场中综合考虑电力系统运行的经济性与安全性，建立了包含电网约束条件的机组组合数学模型，并将其分解为具有整数和连续变量的两个优化子问题。在分析 Ｌａｇｒａｎｇｉａｎ 分解与协调算法振荡机理的基础上，选择机组运行状态改变后的系统边际费用为协调因子，提出了单调收敛的新方法。该协调因子取决于机组的物理参数和系统负荷不平衡的程度，是各机组运行状态改变后对系统运行费用影响的精确度量，因而方法的快速性和收敛性明显优于 Ｌａｇｒａｎｇｉａｎ 乘子法。通过对 Ｉ Ｅ Ｅ Ｅ２４ 节点系统的计算。

In order to combine the economics with the security of power system operation in electrical market, the mathematical model of unit commitment with security constraints was established, and which was decomposed into two sub problems: one with integer variables and the other with continuous variables. Based on analyses of the oscillation mechanism of Lagrangian Relaxation (LR) approach, the system marginal cost was selected as the co ordinator for each unit due to its operating state's change, novel algorithms for effectively co ordinating these two sub problems was presented. Such co ordinator was calculated according to the physical parameters of unit and the unbalance of system demand and is the accurate measure for system cost variation due to the change of unit operating state. Comparing to conventional LR approach, the proposed algorithms perform better in terms of calculation speed and convergence property. Such advantages are demonstrated through the IEEE 24 node system.