Power Quality Assessment for a Fluctuating Load Based on the Electrical Transient Analysis Program

Before a new power customer is connected into the power grid, it is an important task to assess the possible impact of this new load on the power quality. This paper proposes a method to analyze the voltage fluctuations and harmonics for the characteristics of many types and quantities of internal frequency conversion equipment and motors in the power consumer. First, the principles and methods for model establishment of voltage fluctuation analysis and harmonic analysis are introduced. Then, according to the actual operation of the loads, the simulation model is established in ETAP (Electrical Transient Analysis Program). The voltage fluctuation and the harmonics injected into the power grid caused by the operation of loads are obtained through simulation. Since the phenomenon that the harmonics exceed the standard in the extreme operating condition, this paper gives reasonable control measures based on the actual condition of the load, the simulation results and the allowable values prescribed by national standards. (paper)