对高压直流输电工程进行规划、设计时，优化选择设备的型号以取得最大的经济和可靠性效益已成为日渐重要的问题。基于成本效益分析原理，综合计及直流输电系统的可靠性和经济性，给出了高压直流输电系统设备最优选型模型及算法。分析了设备的投资费用、运行维护费用和系统停电损失费用等的计算模型，并在此基础上建立了高压直流输电系统设备最优选型的数学模型，该模型属于离散非线性优化模型，基于遗传算法给出了模型的求解算法。采用整数编码、自适应交叉率和变异率对遗传算法进行改进，并结合直流输电工程实际提出子系统可靠性保留技术，改善了算法收敛性和计算速度。对一单12脉接线高压直流输电系统进行了设备最优选型的算例分析。结果表明，该模型和算法可行，对高压直流输电系统的规划、设计中设备选型有重要的指导作用。

How to determine the optimum type of components to obtain the maximum benefit considering the cost and operational reliability is becoming an important issue in the HVDC system planning and design processes. Based on the cost-benefit principle, the model and algorithm of determining the optimum type of components in HVDC systems is proposed. Considering the investment, maintenance and outage costs, this problem was formulated as a nonlinear and discrete optimization model. An improved genetic algorithm with an integer coding technique and adaptive probabilities of crossover and mutation was used to solve this problem. The computation effectiveness of the proposed method was also improved using the technique of saving the reliability of subsystems according to the inherent characteristics of HVDC systems. A single 12-pulse HVDC system was used to illustrate the proposed technique. Case studies indicated that the model and algorithm were feasible. Results also showed that the proposed method is an appropriate tool to determine the optimum type of components in HVDC planning and design processes.

“十一五”国家科技支撑计划重大项目(2006BA A02A21)；国家自然科学基金项目(50777067)；重庆市自然科学基金重点项目(CSTS2008BC7031)；输配电装备及系统安全与新技术国家重点实验室项目(2007DA10512709103)。