A low-voltage apparatus short circuit tolerance strength test intelligent protective device

Abstract

The invention discloses a low-voltage apparatus short circuit tolerance strength test intelligent protective device comprising a measuring device, a data processing device and a control device; the measuring device is used for real-time measuring of the voltage waveform and current waveform at an incoming end of a test sample and providing a data source for the data processing device; the data processing device is used for determining whether the voltage waveform and the current waveform are abnormal through a current harmonic content abnormality detecting algorithm and according to the voltage waveform and current waveform monitored and collected by the measuring device in real time during the short-circuit test, and outputting a control signal to the control device when an abnormality occurs; and the control device is used to receive the control signal transmitted by the data processing device, control opening of a high-voltage side circuit breaker of the short-circuit test system, and protect the test sample from persistent long-term abnormal voltages or currents, thus avoiding risks such as damages and blasting and protecting the safety of the short-circuit test system and testpersonnel.

Description

technical field [0001] The invention relates to the field of power electronics, in particular to an intelligent protection device and a protection method for a short-circuit withstand strength test system of a low-voltage electrical appliance. Background technique [0002] According to the latest national standards GB / T7251.1-2013, GB / T1094.5-2008, and related IEC international standards, the short-circuit withstand strength test has always been a key test item for the CCC certification type test of low-voltage electrical equipment, components, transformers and other products , Electrical equipment must be able to withstand the thermal stress and electric stress generated by the maximum to the rated short-circuit current, and the test current generally ranges from several thousand amps to several hundred thousand amps. [0003] At present, my country's low-voltage electrical appliance market is huge. There are more than 1,000 types of low-voltage electrical appliances, and t...

AI Technical Summary

Problems solved by technology

According to the requirements of the standard, the short-circuit test is a timed power-on test. After the explosion occurs, if the test time is not up, the sample is still in the power-on state, so the explosion will continue until the end of the system power-on because the power supply is not cut off, further amplifying the loss and risk

[0005] Due to the particularity of the short-circuit test, traditional power system comprehensive protection devices, overvoltage protectors and other protection devices are often installed on the high-voltage side of the test system. Due to the limitations of capacity settings and the particularity of the short-circuit test, they are not suitable for such abnormal situations. protection, and when the test current is large, the low-voltage side is generally not equipped with a protective circuit breaker, only an overvoltage protector is equipped, and the traditional overvoltage protector has extremely limited protection functions, which can neither be differentiated nor quickly response, and therefore cannot provide a truly comprehensive protection

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