Investigation on Voltage Quality Problems on the Process of Cement Industry Production in Indonesia: A Case Study of Cement Kupang Factory - Indonesia

The decline in the quality of electric power becomes a serious problem in the industrial sector and affects a significant cost loss. One of the dominant power quality problems is the voltage dip. The use of electric motors in an industry becomes one of the main causes. This paper discusses the investigation on voltage dip problems at a cement factory at Kupang,, Indonesia. The cement factory uses an induction motor as the prime mover and is proven to trigger a voltage dip because of its high starting current. Based on the observed data of the disturbance, a single line diagram was created. The single line diagram was analyzed using an equivalent circuit. It was found out that as the induction motor was started, it created a very significant voltage drop as of 20.43 % to 62.26 %. The voltage dip correlated to the capacity of the induction motor used. The larger the capacity of the induction motor, the larger the voltage dip occured.