Interpretation of Immunity Time Testing Method under Voltage Sag for Sensitive Process Rated Less than 1000V

Industrial production interruption events due to the voltage sag have occurred frequently in recent years. In order to solve the contradiction between the voltage sag problem and the sensitive industrial production process, it is necessary to obtain the sag immunity time of the sensitive process. Guangzhou Electric Power Research Institute started from the practical problems encountered in the production process considering changes in physical parameters when sensitive processes are affected. In order to obtain accurate process immunity time, a standard testing method for sensitive process voltage sag immunity time below 1000V was developed. The testing method proposed by this standard can sort through the complex production process layer by layer, and identify the weakest link and the most sensitive equipment in the entire process. This article interprets the standard layer by layer, and proves the applicability of the testing method proposed by the standard through actual case.