Research On Reliability Evaluation Method Of Distribution Network With Distributed Power Supply

As the terminal of direct-connected users,the distribution system is centrally distributed at the end of the grid.Data confirm that most of the blackouts in the grid originate from the distribution network.It can be said that the stability and sustainability of the distribution network will directly affect the operation of the large power grid;in the process of industrialization continues to advance today,the speed of energy consumption is increasing,and environmental pollution is becoming increasingly prominent,including wind power,photovoltaic and other distributed generation technology with a series of pollution-free,rich resources.Advantages have attracted much attention and have great potential for development.However,the problem of poor stability exists in distributed generation basically,and the use of such resources needs to adjust and modify the topology of the original grid,which in the invisible for the stable operation of the distribution network has buried hidden dangers,so we need to pay attention to and strengthen the stability of the distribution network with distributed generation.Comprehensive and meticulous assessment of sex and reliability.Firstly,the paper collects a lot of relevant information about this subject,combs and integrates the theories which can be used to evaluate the reliability of distribution network.At the same time,under the guidance of these theories,the author elaborates and analyzes in detail the conventional methods for evaluating the reliability of distribution network,that is,to create a two-state outage model of components,and through a special state enumeration method.Sequential Monte Carlo method is used to select the failure state of the system,and the core load partition algorithm is used to evaluate the selected failure state in a comprehensive and meticulous way.Secondly,the distributed generation technology is briefly discussed,and the reliability evaluation of distribution network with distributed generation is analyzed with emphasis.The analysis contents mainly include: establishing the random output model and load sequence model of distributed generation,deeply studying the island operation state of such distribution network,and creating a new distribution network.The accurate and reasonable islanding model and its dynamic solution are given.Then,the influence of distributed generation fault on distribution network operation is analyzed by synchronous sampling method.After the above work is completed,the reliability evaluation process based on sequential Monte Carlo simulation is fully clarified.Thirdly,the software Microsoft Visual C++ completes the reliability evaluation algorithm well,and then introduces it into the IEEE RBTS Bus6 system for further example analysis.The reliability of the system is evaluated objectively and reasonably by combining analytical method with analogue method,and the results are compared with the results of manual calculation to verify the rationality and correctness of the program design;the main feeder F4 system of the distributed generation and the IEEE RBTS Bus6 system is connected,and various reasonable research schemes are worked out.Its reliability is evaluated objectively and rigorously.The conclusion that using distributed generation can enhance the reliability of distribution network is confirmed.The relationship between distributed power failure,connection location and distribution network reliability is studied quantitatively.