Research On The Evaluation Of Regional Power Grid Operation Mode

Operation mode composition is a piece of basic work of power system dispatch department. Good operation mode ensures the power system to provide continuous and reliable power supply with high quality for the users. Regional power grid, as an important component of power system, connects transmission power grid and power users. Along with the swift development of power grid construction and automation, the operation mode of regional power grids become more and more complicated. And even the quantity of feasible operation mode becomes larger and larger, which turns the selection of operation mode to be a hard job, because the traditional selection method based on experiences becomes unreliable. In that case, it is of great theoretical and practical significance to establish a whole set of scientific evaluation method for regional grid operation mode.A set of index framework consisting of 3 levels is established based on the researches on different topics such as static security, reliability, power quality, economy, short circuit current, complexity of dispatch operation and losses for equipment overhaul. The index framework is made up of 15 lower indexes, 7 mid-class indexes and 1 upper index. The quality of operation mode can be decided by comparing with the upper index.In order to realize the computation of index framework, a so called 'probabilistic evaluation algorithm'is developed to modify the indexes which are traditionally used to evaluate single equipment, such as load-rate and capacity-load-ratio, and enable them to evaluate the whole power grid. Besides, the TOPSIS method is used to normalize different indexes. And in addition, the AHP method is brought in to calculate the weight of each lower index when computing upper index. In the end, the operation mode comprehensive index is obtained by the weighted average value of the mid-class indexes. During the calculation, a topology searching method is used to evaluate the effect of the load transfer on operation mode.In the end, this evaluation method is proved effective and feasible through the practical application in a regional power grid of Shanghai, where 3 pieces of operation mode were evaluated and compared.