基于不同变压器调档所引起的电压无功变化在稳态电网中具有近似线性叠加性质，提出一种简单实用的变压器调档策略，以满足电网的无功电压调控需求。在当前潮流下计算变压器抽头变动一档引起全网节点的电压和无功变化级差（步长），定义为一档电压效应和一档无功效应，以抽头变化量（步数）及无功改变量之和的最小值作为目标函数，以全网节点达到目标控制电压范围内作为约束条件，对变压器档位进行组合优化计算，得到优化调档策略，可作为全局优化的预优化计算或变电站档位规划。某实际电网的计算表明此方法简便实用。

The change of voltage and reactive power in stable system caused by tap changing of different on-load tap changers (OLTC) has the nature of nearly linear superposition. Based on this, the strategy of changing the tap of OLTC is proposed in this paper, for satisfying the requirements of reactive power control. The step changes of voltage and reactive of all network nodes in power system caused by tap change of OLTC are calculated in initial power flow, which is defined as voltage effect per tap(VPT) and reactive effect per tap(QPT). The optimal strategy is obtained, by minimizing both taps changes(steps) and reactive power changes as the objective function, restraining the voltage of whole network buses to the control range, and optimizing the combination of transformer taps. The actual calculating example shows that the method is simple and practical.