基于概率潮流的未来输电线路经济评估

Economic Assessment of Future Transmission Line Base on Probabilistic Power Flow

输电网扩展规划时要对方案的经济性进行评估,而输电网的收益主要取决于过网费和输电线路上通过的功率量。提出了一种估算未来输电线路流量的概率潮流方法,帮助电网规划人员评价方案的经济效益。该方法充分考虑未来负荷概率分布、负荷间相关性、发电机停运概率以及机组经济调度等不确定性因素,采用蒙特卡罗抽样方法,建立了未来线路过网流量的计算模型。基于该方法,可有效分析线路过网收入,进而更准确地计算出规划方案的经济效益指标,如净现值、内部收益率、投资回报期等,指导电网规划方案的经济评估。New England测试系统的案例分析验证了上述方法的有效性与应用价值。

It is necessary to conduct economical assessment on the planned scheme during the development of transmission network expansion planning. In view of the fact that the revenue of transmission network is largely depended on the wheeling charge and the flow rate flowing through the transmission lines, a probabilistic power flow method to estimate the flow rate of the future transmission line is proposed to assist the power network planner in assessment of economy benefit of the planning scheme. Considering such uncertain factors as probabilistic distribution of future load, correlativity among loads, probability of generator outage and unit commitment and utilizing Monte Carlo sampling method, a calculation model for the wheeling flow rate passing through the future transmission line is built. Based on the proposed method, the income from wheeling charge can be effectively analyzed, and further the economic benefit index such as net present value （NPV）, internal rate of return （IRR） and pay back time （PBT） can be calculated to guide the economic assessment of power network planning scheme. The effectiveness and application value of the proposed method are validated by the results of case analysis of New England testing system.