Reliability And Its Parameter Evaluation Of Transmission System With Weather

In recent years,the scale of power system is expanding,and the uncertainty of power system is becoming more complicated and diversified.In the previous research on transmission system reliability evaluation,component model is based on the model of Markoff transfer process.However,the original parameters,such as failure rate and repair rate,are affected by weather factors,which are not constant.Under normal weather conditions,the failure rate of components is low,which is more sporadic failure,and the component repair process is faster.Therefore,the reliability problem is not very serious.If we can build component failure model under different weather condition,it is concluded that the reliability assessment on transmission system under different weather conditions,and gives a different weather condition change law of system reliability index,then power grid company can advance organization,early repair of equipment,reduce blackouts.Thus,this paper combined with the actual situation of the transmission system,from different angles on the effects of complicated weather condition for reliability evaluation.The research includes the following aspects:In fully studied the previous power system reliability parameters estimation method based on historical data,and analyzes the characteristics of the random variation of weather,according to one direction rough set theory with rules and dynamic migration characteristics,the use of one direction rough set theory in one direction rough rules,establish based on one direction rough rules of component failure rate model.The model through to component reliability original parameters influencing factors(weather)factors analysis based on,using one-way rough law method,establishment of transmission line failure rate model,and the transmission line fault rate was estimated.Finally,the failure rates of overthead lines as an example,for unknown fault line rate,the results verify the feasibility of the method.Based on the principle Hidden Markov,there are two ideas,one research presents a hidden Markov chain Monte Carlo algorithm to assess the reliability of the system,the method in the state of the weather,the state of the system and the transition matrix based on the hidden Markov model is solved to obtain the count and system state weather observation sequence.Bringing it into the reliability evaluation system to give account of the state of the weather system reliability evaluation.Another idea,it is through hidden Markov to obtain component failure rate for each weather condition.Based on the principle of one direction S-rough sets theory F-decomposing law analysis,different complex weather characteristics of F-decomposition rule analysis method of the system reliability under complex weather conditions,can on the reliability index of the uncertainty is determining the metric and optimization of system reliability assessment method,reveal the effect of weather factors on the reliability assessment.Finally,the reliability index is obtained by using the method of comparing with the conventional method,the presented method is effective and reasonable.In this regard,take corresponding measures according to the influence of the weather,to improve the system reliability and the ability to deal with adverse weather,provide important reference information for planning and operation.