Wuhan UHV specializes in producing series resonance (also known as variable frequency series resonance test device). Next, we will share with you the characteristics of the variable frequency series resonance test device.

Series resonance test

First of all, let's talk about the series resonance test, which is also commonly known as the AC withstand voltage test. It is the most effective and direct way to identify the insulation strength of power operating equipment before commissioning, and can play a decisive role in the pre commissioning process. Series resonance is a principle technology of electronic circuits, and it is a method or preventive test for insulation testing. Due to its large test capacity and high voltage, series resonance is widely used in power generation, power supply and other departments.  

The significance of series resonance test

During the operation of power equipment, insulation will gradually deteriorate under the long-term effects of electric field, temperature, and mechanical vibration. The degree of degradation includes overall degradation and partial degradation, and defects will form over time. For example, during production and installation, areas with concentrated electric field or weak insulation ratio are prone to insulation breakdown. Of course, various preventive testing equipment have their own strengths and can detect some defects that reflect the insulation condition. However, it can also bring some hidden dangers, such as DC withstand voltage test, which was a mainstream method in earlier years and does not have high requirements for the capacity and voltage of the testing equipment. Since voltage is distributed according to resistance, insulation degree cannot be detected under DC voltage. DC effect, On the contrary, it will accelerate the aging and failure rate of power cables. With China's research and testing in technical testing, it is recommended to use AC voltage for testing, which is in line with the voltage conditions that power equipment can withstand during operation. At the same time, the operating test voltage is higher than the operating voltage. After being powered on, the equipment has a larger margin, and its principle is "series resonance". Due to the increase in insulation medium loss, heat generation, and discharge caused by high voltage, it will accelerate the development of insulation defects. Therefore, series resonance testing is also a destructive test. Compared with DC, series resonance testing is more likely to detect insulation defects. This is also the significance of series resonance testing, which is widely recognized and promoted.  

Precautions for series resonance test

When conducting a series resonance test, various non-destructive tests must be carried out first, such as measuring insulation resistance, absorption ratio, dielectric loss factor, DC leakage current, etc. The data must be comprehensively analyzed to determine whether there is moisture or defects. If problems are found, they need to be resolved first, and then the series resonance test can be conducted.