Implementation of Distributed Generation for Voltage Drop Reduction in Electric Power Distribution Systems
Abraham Lomi*, Sukumar Kamalasadan**, and Kartiko Ardi Widodo*

*Dept. of EE, Institut Teknologi Nasional Malang, INDONESIA
**Dept. of EE, The University of North Caroline at Charlotte, USA

Abstract

The electricity demand is growing rapidly due to the increased development activities which may lead to many problems in the operation of power systems such as the power quality, reliability, and control of the power system, etc. since there are many nonlinear and sensitive loads. Power quality can range from simple steady-state low voltage profiles to transient problems, such as oscillatory and surges. In the early days of the electric power industry, distributed generation (DG) was introduced as a source of energy near the point of consumption on a small scale. However, they became quickly unpopular afterward due to their lower efficiency compared to centralized generation. Nowadays, with market liberalization, environmentalism, and technological advance, distributed generation (DG) become more important and popular in power systems, especially in the power system area. Traditionally, poor voltage profile problems can be addressed by using tap-changing transformers, capacitors, etc. With the increase of DG units connects to the distribution networks, the power flow direction will change, depending on production and consumption at a certain time. This will result in changing voltages due to reduce branch current along the feeder. However, the problem of poor voltage profile is only improved if DG is allocated and sized optimally. A genetic algorithm (GA) method is selected to optimize the location and size of DG while the sensitivity factor analysis (SFA) is selected to search the sensitivity buses for DC placement. A 69-bus test system is adopted to run the simulation and showed that the GA finds bus No. 63 as the best location for DG placement. The minimum size of the DG required to ensure the voltages at all load buses lying within the permitted range is 2.16 MW. This allows reducing the total voltage drop from 1.5437 kV (a case of no DG) to 0.5439 kV or contributes to 64.82% total voltage drop reduction. While the sensitivity factor method shows that bus No.57 is the most suitable location for DG placement with a minimum size of 2.61 MW and reduces the total voltage drop 0.8391 kV or counts for 45.69% total voltage drop reduction. In addition, it is clear to show that the DG size in the GA method is smaller than that of the SFA method but the efficiency of improving the voltage profile of the first method is better than that of the latter.

Keywords: distributed generation, genetic algorithm, voltage drop, sensitivity, power quality

Topic: Distributed Energy Resources