电力系统中长期生产成本模型和方法对比研究分析

Comparative Study on Middle and Long Term Production Cost Models and Methods of Power System

随着间歇性可再生能源并网比例的不断增加,电力系统对运行灵活性的要求也越来越高,需要对电力系统规划方案开展长周期细时间尺度的生产模拟仿真,以揭示规划周期内电力系统运行的细节,从而展现运行灵活性的供需平衡情况。生产成本模型中采用不同的优化模型和方法、不同的解耦迭代方式,都会对仿真结果产生不同的影响。为了评估这种影响,在已知电源电网检修计划的前提下,建立了基于安全约束机组组合和安全约束经济调度的生产成本模型,在时间维度上提出了3种模型的解耦迭代求解方式,并派生出5种中长期生产成本仿真方案,通过RTS-96系统的算例仿真,对比了不同生产成本仿真方案的计算速度与精度。算例结果表明,时段间的耦合约束和运行日间的耦合对计算精度有很大影响,合理的优化模型和解耦迭代方案能在保证计算精度的同时,提高求解效率。

With the increasing proportion of intermittent renewable energy integration,the power system increases the demand on operation flexibility.It is necessary to carry out production simulation in fine time scale for a long period to reveal the details of the power system operation within the planning cycle and show the balance between supply and demand of operation flexibility.Using different optimization methods and different way of decoupling iteration in production cost models both had different effects on the simulation results.In order to evaluate this effect,the production cost model based on security constraint unit commitment and security constraint economic dispatch on the premise that maintenance scheduling of units and power grid is known were built.Three decoupling iterative methods in time dimension was presented.On this basis,five mid long term production cost simulation schemes were derived.Through the simulation of the RTS-96 system,the calculation speed and accuracy of different production models were compared,and the results of case study showed that the coupling constraint between time periods and the coupling between running days had a great influence on the calculation accuracy and reasonable optimization model and decoupling iteration scheme could improve the solving efficiency while ensuring the accuracy of calculation.