Study On The Inductance Identification And Control Of The Actuator Of Monostable Permanent Magnet Vacuum Circuit Breaker

As well as the social economy is developing rapidly,the demand for electric energy is increasing.The quality and reliability of power supply is highly demanded by users,and Smart Grid has also become an inevitable trend.Circuit breaker is one of the important equipment in power system,while the actuator is the core part of a circuit breaker.The performance of the whole circuit breaker is mainly influenced by the reliability and intelligence of its actuator.With the advantages of simple structure,less fault source,long service life and high reliability,permanent magnet actuator has been developed rapidly in recent years and has been more focused on.Monostable permanent magnet actuator is the main research object of this paper.In the process of the research on the monostable permanent magnet actuator,the inductance of its drive coil has been founded nonlinearly changing,which makes it difficult for the intelligent control.Therefore,the main research direction of this paper is the study on the coil inductance identification of the monostable permanent magnet actuator and the system intelligent control strategy based on the coil inductance identification.First,the structure characteristics and working principle of the monostable permanent magnetic actuator are introduced detailedly.Then,the electromagnetic model of a real monostable permanent magnetic vacuum circuit breaker actuator is built on Ansoft Maxwell.Based on the electromagnetic field theory and the finite element method,the static and dynamic characteristics of the actuator are calculated respectively,and the changes of displacement,speed,coil current and excitation capacitor voltage are analyzed.Next,the flux current method,the differential equation method and the energy perturbation method are carried out to identify coil inductance in the process of a certain movement.By comparing the identification results of these three methods,the feasibility and effectiveness of the methods in realizing coil inductance identification are verified.Then two kinds of coil inductance identification methods based on non-linear model are proposed,which are suitable for more movements.The two methods are tested by using a certain movement characteristic,and the results of two methods are close to each other.Finally,according to the coil inductance identification,a system model of the monostable permanent magnet actuator is established on the Simulink software.The intelligent controller is built by using the single neural network adaptive control technology.The dynamic characteristics are significantly improved after control,which proves that the intelligent control strategy is feasible and effective.