Modeling And Reliability Analysis Of Electric Valve Distribution System In Nuclear Power Conventional Island

As a key component of the I&C system,the status of the electric valve in the conventional island of nuclear power is related to the operation safety of the related system of the conventional island of nuclear power.At present,the design of the electric valve distribution system in the conventional island of nuclear power mainly considers the selection of the distribution cabinet with large capacity to avoid the occurrence of overload of the system.However,the impact on the load balance of the distribution system and the correlation of the process system is considered On the other hand,in the process of power automatic switching device switching,because the electric valve in the same distribution cabinet can not perform its function normally,the normal operation of the main system of the conventional island will be endangered.In order to meet the design requirements of I&C power distribution in the double power automatic switching scheme in the national nuclear power unit design standard,strengthen the ability of the existing I&C power distribution system design to adapt to the process system,so as to effectively meet the reliable operation requirements of the unit and improve the automatic design level of the power distribution system.Therefore,it is necessary to optimize and analyze the reliability of the electric valve distribution system of the conventional island of nuclear power in order to improve the power supply quality of the electric valve distribution system of the conventional island of nuclear power and ensure the safe operation of the conventional island system and equipment.Based on the field data and the operation of related systems,this paper proposes a distribution system optimization method with load balancing rate as the goal,which takes the power flow,branch voltage and current as the constraints.By using greedy algorithm and improved adaptive step size cuckoo algorithm,the distribution system optimization analysis is carried out.Through comparison,it is found that the adaptive step size based cuckoo algorithm Compared with the greedy algorithm,the computational efficiency is similar,but it has better global optimization ability and good versatility.Combined with the simulation test of the electric valve distribution system of a domestic power plant,the results show that the reconstructed electric valve distribution system makes the load distribution of each distribution cabinet more balanced,the load imbalance degree of equipment and the maximum imbalance degree index after distribution are significantly reduced,and the equipment is more fully used,which can effectively solve the problem of heavy load and even overload of some lines.This paper uses fault tree method to analyze the failure probability of three-way water supply pump in the optimized distribution system of electric valve based on the adaptive step size cuckoo algorithm.The results show that the failure probability of three-way water supply pump is reduced from 4.3367 × 10-30 to 7.3614 × 10-36 after reconstruction,which is far lower than that before reconstruction.It fully proves that the optimization scheme not only improves The balance degree of distribution system also improves the reliability of power supply.