Research on a Novel Framework of the Fuzzy DP and its Application to Power System Planning

动态规划算法是解决电力系统规划中多阶段决策问题的一种方法。在时序决策过程中，如最优未来规划问题，问题本身必然包含不确定性因素，提出了一种新的模糊决策过程框架，通过判断隶属度函数之间的优劣来确定最优路径。该框架基于目标函数本身可以通过直接考虑不确定数据而得到模糊数的特点。在这种新的框架中，所得到的最优解具有一定的宽度，该宽度将由于数据的不确定性而必然出现。换句话说，最优解被确定为一个集合。在模糊环境下，任何属于该集合的决策都是平等的。此外，在本研究中，作者考察了…的特征和影响将改进的模糊DP算法应用于电力系统中典型的规划问题--水火电调度问题和发电计划问题，进一步证明了该算法的有效性。在水火调度问题中，水库的自然入库流量和电力需求均以模糊数的形式给出。结果表明，水库的最优调度可归结为带带解。在发电规划问题中，通过将未来成本(固定成本和变动成本)定义为模糊数，提出了一种求解未来最优发电机组组合的方法。同时，对该方法进行了扩展，使系统规划者可以通过将需求的不确定性设置为多个情景来灵活地应对电力需求增长的任何情况。在此基础上，作者提出了一种考虑从确定引入到运行开始的时间滞后来确定最优电源扩展规划的方法。较少

As a method for solving multistage decision making problems in power system planning, the Dynamic Programming (DP) algorithm has been used. Here, in the time sequential decision making process such as the optimal future planning problem, uncertainty factors are necessarily included in the problem itself.In this research, the authors developed a novel framework of the fuzzy DP where the optimal pass can be deterimined by judging the superiority between the membership functions. This framework is based on the characteristics that objective function itself can be obtained as a fuzzy number by the direct consideration of uncertain data. In this novel framework the optimal solution obtained has a width which will be appeared necessarily as a result of data uncertainties. In other words, the optimal solution is determined as a set. Any decision making which belongs to this set are equal under the fuzzy environment.Further, in this research, the authors investigated characteristics and effect … More iveness of the developed fuzzy DP algorithm by applying it to the hydro-thermal scheduling problem and the generation planning problem which are typical planning problems in the power systems. In the hydro-thermal scheduling problem, the natural inflow to reservoirs and the power demand are given as fuzzy numbers. As a result, the authors could obtain the optimal operation of reservoir as the solution with a band. In the generation planning problem, the authors developed a method for obtaining the future optimal mix of generators as the solution with a band by defining the future costs (fixed cost and variable cost) as fuzzy numbers. Also, the developed method was extended so that the system planner can cope with any senario on the increase of power demand flexibly by setting the uncertainty of the demand as several scenarios. Further, the authors developed a method for determining the optimal generation expansion planning considering the time-lag from a determination of introduction to a start of the operation. Less