Voltage Sag Assessment in a Large Chemical Industry

This paper presents a method for the assessment of voltage sags caused by short-circuit faults in a large chemical industry. The supply arrangement for the industry is discussed. The connected equipment of the industry is fed from the 6.6-kV bus. The voltage sag analysis is performed for faults at different voltage levels in the power supply network. For every voltage level, the critical distance and expected number of voltage sags have been calculated. Since the industry has its own generator, thus the influence of local generation in voltage sag analysis is also investigated.