The Research On Test Condition Of Relay's Electrical Life And Intelligent Techniques Of Its Test Device

As a kind of typical controlling apparatus, the relay is widely used in many control systems. The high performance of relay will be claimed lest the reliability of the entire system employing the relay is on the decline. Even worse some fates may be resulted in. Through the electrical life test of relay, not only can the index of relay's electrical life be abtained, but the main causes of failures be found, for the sake of improving the relay's quality. The research about the methology, standard and electrical life-test devices of relay is an important focus in the overseas and domestic research field.Moreover, after the test device and apparatus are devised up and put into use, the users always believe there is a matter with the relay itself once the faults ocur. It is commonly believed that this behavior is very arbitrary. In a matter of fact, there are a variety of reasons can acount for these faults. Consequently, it is required an easy and effective approach to pinpoint its derivation and nature.In this paper, the main tasks are performed on two aspects.On one hand, we have a theoretical research on electrical life test condition of relay loaded with a single-phase asynchronous motor (SPAM). Firstly, begin with building a mathematical model of relay's load, or a single-phase asynchronous motor, we analyze the transient process of the SPAM when it starts and stops by means of qualitative and quantitative methods. Secondly, the actual measurement results are measured and compared with the aforementioned theoretical simulation ones. Therefore the research theory is waterproof. Lastly, we arrive a conclusion on test condition of relay's electrical life-test device when simulating motor load. This kind of test condition includes the voltage across relay's contacts and current through its loop circuit.On the other hand, we also have an exploration on the intelligent techniques of relay's electrical life-test device. Above all, we have introduced the Fault Tree Thoery, which was originated in the1960s. Based on the Fault Tree Analysis (FTA), the main loop circuit of electrical life-test device is studied and its corresponding fault tree constructed. Then we look for the minimal segmental sets of the created fault tree. Finally, the realization algorithm is accomplished according to the minimal segmental sets.