The Reliability Evaluation Research Of A Regional Power Grid With Distributed Generation

Recently, the rapid development and wide application of the distributed generation technology, not only can improve energy efficiency in order to protect the environment, but also have a positive significance ease for the contradiction between the peak power shortage in the Case of the global energy crisis and environmental pollution is worsening. Therefore, it has a great benefit Whether for the national energy strategy or for the reduction of environmental pollution from the pursuit of sustainable development perspectives. But, Large-scale distributed generations connected to the power system will make it into a new one where power supply and the loads Spread all over. With the structure and operation mode becomes different of the new grid, the theory and methods to evaluation the reliability of power supply also changed.The characteristics, Access location, network-Accessing mode of DG were researched fully. This paper established a multi-capacity units of wind power and improved dual state model of small hydropower. More synthetic output state units are set to fewer groups by clustering technology, according to the random characteristics of DG power output. with the equivalent of only consider generators and electricity load of two-terminal system,Secondly, the outage capacity preliminary sorting table are created to reduce the calculation steps and save time,against the cumbersome problem of calculation for outage Capacity probability model. The capacity model and daily peak load model are combined to evaluate a new power generation system margin assessment system, with only considering generators and electricity load as a two-terminal system. MATLAB program is compiled to calculate reliability indexes to evaluate the reliability for using a actual power generation system with multiple wind farms and many small hydropower as an example.Then, various types faults of feeder、distribution transformers、circuit breakers、 fuses、etc are combined with feeder segment. And, this method is used to simplify a actual complex distribution network with multiple wind farms. Then, the improved FMEA method is used to analyze the hypothetical faults. Consequently, a electric network is built and the reliability is evaluated based on DIgSILENT platform. The practical example demonstrates the effectiveness and feasibility of this proposed method.Finally, Strategies and recommendations are given to improve the system reliability from two angles of technical and management improvements based on the results of the reliability evaluation for a regional power grid power systems and distribution systems with distributed power.