中文摘要：

电力市场环境下发输电系统的规划评估决策在某种程度上是可靠性和经济性的博弈，其关键是可靠性的经济度量，由此决策发输电系统应该预留多少安全裕度。目前发输电系统扩展规划中的可靠性决策，往往利用单一用户停电损失值将发输电系统可靠性指标化为经济性指标，作为发输电系统规划的优化目标。针对这一不足，该文应用经济学中无差异曲线的分析方法，建立了发输电系统扩展中可靠性的经济价值评估与决策模型，解决了从经济性角度对可靠性进行度量的关键问题。据此对发输电系统规划方法进行改进，并用实例验证了该经济价值评估方法的有效性和实用性。

英文摘要：

Generation and transmission expansion in power market environment is partly a trade-off between economic efficiency and reliability. The key factor is the assessment of reliability, and then the reserved capacity of generation and transmission system is determined. The prevailing reliability assessment methods, by applying outage cost of customer, usually convert system reliability index into economic index to build up the optimal object. Concerning this shortcoming, the paper applies the indifference curve in the economy to establish the reliability assessment and decision-making model in generation and transmission planning, solving the key issue of how to assess the economic value of reliability. Moreover, the paper improves the generation and transmission planning approaches due to the introduced model, and the validity and practicability of the method is proved by the example.