The abnormal phenomenon of the microcomputer relay protection tester is often at the system level, but the cause of the fault is at the component level and material level, and the multiple possibilities of the fault cause make it difficult to locate the fault. Therefore, the task of abnormal phenomenon information diagnosis is to inject historical statistical data and faults, and prescribe the right medicine for the abnormalities of the microcomputer relay protection tester. The judgment and prediction of the degree of failure damage are carried out in sequence. There are three main methods for fault diagnosis of the microcomputer relay protection tester, which are as follows:

1. Probability trend diagnosis

The probabilistic trend diagnosis method uses the key parameter set corresponding to the abnormal phenomenon to establish the probability trajectory of each parameter change and fault damage based on historical data, and then compares the current multi-parameter probability state space to judge the current health status and analyze the trend. Through the interference of the current parameter probability space and the known damage state probability space to perform quantitative damage judgment, you can intuitively check out the key problems of the (microcomputer) relay protection tester.

2. Basic diagnosis analysis

The basic diagnostic analysis is to use the establishment of the dynamic response mode of the observed object to identify the parameters according to the response output of the current system, compare the statistical characteristics of the parameters in the normal state, and perform the failure mode to confirm whether the microcomputer relay protection tester is in good condition. This method provides a different approach from probability trend analysis, through which the alarm effect can be quickly achieved.

Three, comprehensive diagnosis

This diagnosis method uses parameters from a variety of information sources, sensor information, and a combination of historical and empirical information to analyze the self-check of the microcomputer relay protection tester, so as to reduce errors in work, and can effectively improve the degree. The best choice for data fusion.