Load-side voltage sag assessment : hands on investigation in Malaysia industries

Abstract

Voltage sag is short duration reduction of RMS voltage and it is recognized as the most serious power quality problem for industries in Malaysia. The impact of voltage sag to the industrial equipment depends on the severity of voltage sag and the sensitivity level of equipments itself toward voltage sag. The concept of EMC for voltage sag problem call for utilities, customers, equipment manufacturer and regulators to play their role in order to minimize the impact of voltage sag by virtue of complying to SEMI F47 and MS IEC 61000 curve. This project focuses on determining the sensitivity level of selected industrial equipments by conducting Ride through Test (RTT) using CHROMA 6530 Programmable AC Source and PSL Industrial Power Corruptor. The industrial equipments selected are the production machine for Semiconductor industries (Tester Machine, Wire Bond Machines and Die Attached), Programmable Logic Controller (PLC) and Magnetic contactors. The sensitivity or Immunity level data of the selected industrial equipments against voltage sag has been established. Comparison on the sensitivity level among similar type of equipments is also performed. It is evident from the RTT results, that majority of semiconductor equipments are very sensitive to voltage sag. The RTT results for PLCs and magnetic contactor also indicate that these two equipments are very sensitive to voltage sag and establish themselves as one of the ‘weak links’ in industrial equipment system. The established sensitivity data for the industrial equipments is helpful in predicting estimated loss due to voltage sag and determining the best cost effective voltage sag mitigation solution to the industrial equipments.