Optimal Planning Of Distributed Generation Based On Credible Capacity

With the increase of distributed generation integrated into the grid arouse problems like voltage violation caused by inappropriate configuration of distributed generation.The appropriate configuration scheme of distributed generation can not only meet the traditional grid security constraints,but also improve the benefits of distributed power access to the grid to some extent.Thus,an optimal configuration method of distributed generation based on credit capacity is proposed in this paper to help realize the optimal choice of distributed generation configuration scheme.Around optimal configuration of distributed generation,it is firstly introduced the research status of distributed generation planning in this paper.Then the impact of different distributed generation configuration on the distributed network is compared and the idea of joint configuration of distributed power supply and island switch to improve system reliability is proposed.To demonstrate the contribution of distributed generation on reliability,a credit capacity indicator for substitution of line capacity is proposed and solved with secant method and,at the same time,ENS regression sensitivity indicator is adopted to portray the expected energy not supplied change under the unit load change.With the impact of distributed generation on system reliability and economy taken into consideration,three indicator systems are established concerning reliability,economy and power substitution ability respectively,then a comprehensive evaluation index system is established which consists of system Energy not Supplied,system power outage time expectation,system power outage frequency expectation,average power supply availability,investment cost,reduced load loss,credit capacity,ENS regression sensitivity.Furtherly,the improved AHP method is adopted to comprehensively evaluate different configuration schemes.Taking RBTS BUS6 as the test case,a variety of schemes for the joint configuration of photovoltaic,energy storage and island switches are established.At the same time,program is written based on the comprehensive evaluation indicator system to comprehensive evaluate different schemes to get the optimal solution,and in-depth analysis of the results of different program indicators is carried our.According to the analysis of the results of the case study,the configuration of the distributed power supply is not only related to the configuration capacity,quantity,location,etc.,but also related to the island location and the number of islands where the distributed power source is located.The contribution of the distributed power source to the credit capacity of the power grid is not single positively correlated with its installed capacity and quantity.Besides,as the installed capacity and quantity of distributed power supplies increase,the system's trusted capacity and related indicators become worse due to the increase of the probability of failure.