针对富含小水电的配电网容易出现丰水期小负荷时电压偏高、枯水期大负荷时电压偏低的问题，提出综合运用增大导线横截面积和部分架空线改造成三芯架空电缆的方法解决富含小水电配电网的电压质量问题。分析了小水电造成电压质量问题的原因，指出减小R和X可以同时解决电压偏高和偏低问题，以投资最小为目标函数，考虑导线加粗和改造成架空电缆的费用，建立了线路改造优化模型，采用随机优化算法求解出最佳改造方案。给出了一个典型算例进行了详细说明，结果表明所建议的方法能够有效改善富含小水电配电网的电压质量。

To solve the problem of voltage deviation of the distribution networks with rich small hydropower, an approach of feeder improvement is suggested, in which, comprehensive application of expanding the cross section of conductors and cable replacement are used. The influence of the small hydropower on voltage deviation is analyzed. It is pointed out that both the high voltage and low voltage problems can be solved by reducing the resistance and the reactance of the feeder. The optimization model is established, in which, the investment of conductor expanding and cable replacement is used as the index. The random optimization algorithm is introduced to find out the best planning scheme. An example is given to illustrate the proposed approach, the results of which show that it is feasible and effective to improve the voltage quality of the distribution grids with rich small hydropower.