Analisis Pengaruh Pemasangan Pembangkit Tersebar terhadap Stabilitas Jaringan Distribusi 20 KV di Kota Medan

Abstract

Distributed Generations (DG) power permits active or reactive power to improve voltage profiles, thereby reducing grid load. But this integration can cause network stability problems. The stability carried out in this study is transient stability. This research is focused on the 20 kv distribution network of Medan city for TD 1 GIS Listrik substation (LK.06, LK.07, LK.08, LK.09, LK.10). This analysis uses ETAP software. Simulations were carried out for 2 cases, namely the installation of 4 DGs with a capacity of 10 MW each and the second case of installing 2 DGs with a capacity of 20 MW each. Transient stability analysis is performed for 4 types of disturbances, namely 3-phase, Line-To-Line (LL), Line-To-Ground (LG) and Line-To-Line-To-Ground (LLG) disturbances. Disturbance simulation is carried out when t = 1 second and the disturbance disappears when t = 1.5 seconds for each simulation. From the research results, it is found that the response of power angle, active power, frequency and line voltage when there is a disturbance experiences a very large oscillation due to changes in the load that occurs and returns to stability after some time after the disturbance disappears. As a result, the performance of DG synchronous generators is destabilized during disturbances. In the first case, it takes longer to return to a stable state when a 3-phase fault occurs, while for the second case when an LL fault and LG fault occur. This is because when these disturbances arise, the short circuit currents that arise are also very large so it takes longer. Therefore, it is necessary to calculate very carefully in the installation of DG in the distribution network in Medan city.