By hvhipot 
HV Hipot Electric Co., Ltd. specializes in producing series resonance (also known as series resonance withstand voltage equipment). Next, we will share with you how to analyze the results of the AC withstand voltage test?
AC withstand voltage test is a preventive testing method adopted for large capacity and high voltage operating equipment in the power system. It is a destructive test for insulation strength, which can effectively avoid sudden faults and large-scale power outages after power operation. AC withstand voltage test, also known as “resonance test”, plays a decisive role in whether the power system can be put into operation. So, how to analyze and qualify AC withstand voltage test?
Requirements for voltage withstand test
Taking 10kV cables as an example, let’s talk about the requirements and results of voltage withstand tests based on the power preventive testing standards. For example, for rubber cables with rated voltage below 18/30kV, the test voltage is 2.5U0 or 2U0, and the test time is 5-60min.
How to analyze the communication withstand voltage test
Before the experiment, we first need to measure the insulation resistance of the tested electric power cable and record the data. Then, we use a 20-300Hz AC withstand voltage test equipment (“series resonance”) to conduct the AC withstand voltage test according to the above requirements. After the test is completed, the cable is fully discharged, and the insulation resistance value is measured. The data results should be very similar to those measured before the experiment, and it can be considered that the cable insulation is good; Secondly, during the test process, the fault alarm signal of the series resonance test device can also be used to determine whether the insulation of the cable is good. The main purpose is to observe whether there are non-human emergency shutdowns, flashover faults, etc. during the test process. If they occur, the cable should be stopped for inspection to check whether the insulation resistance meets the requirements. If it does not meet the requirements, it indicates that the cable has experienced varying degrees of insulation faults and does not meet the requirements for operation. It is important to pay attention to the accumulation effect of the cable during the AC withstand voltage test, and minimize the damage to the cable caused by AC withstand voltage as much as possible.