The Interval Analysis For The Reliability Of Distribution Systems

In the past decades, people have attached much more importance to the generation system evaluation and transmission system evaluation than the distribution system reliability evaluation in the power system reliability evaluation, because the failure of generation system or transmission system may cause serious influence to the power system. However, the distribution system is located at the end of the power system, and it is the point of the power system that links the bulk power sources to the consumer's facilities. The distribution system is an important part that supplies and distributes energy to consumers, operating in the special mode. Therefore, the reliability of the distribution system has a direct effect on the consumer. With the requirement of higher quality energy supply from consumer, the distribution system evaluation has been attached more importance to. Based on the character of the distribution system, having lots of components and having complex structure, the works in this paper are shown as bellow:1. Uncertainty of the original parameters of components may be caused by the shortage of the statistical information or the statistic error. The algorithm of interval is used in this paper with which the original reliability parameters that are changing in a certain range are treated with interval number. Thereby the uncertainty of the parameters can be calculated in the whole process of the reliability evaluation. At the same time the interval reliability indices that are influenced by multi-parameter can be gotten through only once calculation.2. Using the feeder partition method, the structure of the distribution system can be simplified and the speed of the distribution system reliability evaluation can be improved. Therefore, based on the interval theory, the uncertainty of the parameters is calculated in this paper, at the same time, the speed of the calculation is improved and the network structure is simplified.3. An interval method of reliability evaluation in the distribution system is presented in this paper. When this method is used to evaluate the distribution system reliability, interval is used as the components'reliability parameters first. Secondly, the distribution system is partitioned. Lastly, failure is analyzed. During the failure analyzing, in the course of failure recovery, it is considered that the back feeder's load is increased because of the load transfer in the failure feeder. Because of the restriction of the transmission capacity and the voltage level, the load transfer in the...