Technology Of Fuzzy Comprehensive Evaluation Of The Dynamic Characteristics Of AC Contactor

AC contactors are widely used not only for motors but also in a huge number of automatic systems as a type of low-voltage electronic product. As the most frequently used electronic switch, the damages are mostly from the cauterization of contacts. During the start and break moment of the AC contactor, the bounce and the electro-arc of the contact result in shorten of the life-span. It is obvious that, as the executed part, the contacts' working conditions has a directly impact on the quality and the characteristics of the switch.In light of the situations, using CJ20-25 AC contactor as the study object to obtain the parameters which closely interrelated to the important performance of the AC contactor such as the electro-life, mechanical life and the switch capability, this paper presents a technique to deal with fuzziness to combine these parameters into one measure that represent an overall estimate of how well the character was when evaluating the dynamic characteristics, namely the Fuzzy Evaluation of the Dynamic Characteristics of AC contactor. All these parameters are obtained by using of the electro-optical contactor dynamic testing device. The evaluation is specialized with the starting process.Firstly, the basic concept of the fuzzy comprehensive evaluation method is introduced, also the ideology and the detailed step are set forth; Secondly, analyzing the AC contactor's dynamic characteristics with an important conclusion that for the certain dimension structure AC contactors, its dynamic characteristics are depend on the closing making angle of the voltage supply. Based on the theory, the evaluation model is structured answer for the fuzziness, comprehensive and multi-layer of the contactors' dynamic character, and establishing the subjection degree function, so to calculate the value of the subjection degree. And the valuation of the contactors' dynamic character with the different closing making angle is obtained. In addition, fuzzy decision calculating system is designed and implemented by C program, and partly illustrated on an example. This method lays the foundation of designing high performance of the AC contactor.This project combined with the national natural science fund project "study on uncertainty of dynamic response of contact of AC contactor" with the aid of the National Natural Science Foundation of China.