为解决5个串并联水电站的联合调度问题，采用相对比较的方法，在同一计算条件下，将系统分解为三峡梯级与清江梯级2个子系统，分别建立子系统数学模型；通过优化方法求解，得到未联合调度时的发电量；然后建立系统联合调度数学模型，分解协调模型将2个子系统联合优化，得到系统联合调度时的发电。经过对比分析，三峡梯级与清江梯级联合调度后年均可获得补偿电量18.29亿kW•h。

Abstract :This article studied the united operation of five hydropower stations and adopted the comparative method. On the same condition, the system was firstly divided into two subsystems, i.e. the Three-gorges cascade and the Qingjiang cascade, modeled and solved respectively by optimal algorithm, and individual operation results were gained. Then, united operation mathematics model of two subsystems was established and solved by decomposing-concordance algorithm, and united operation results we re obtained. At last, calculated results through contrastion indicated that united operation could get more than 1.829 billion kilowatt-hourselectric power.