Simulation of Power Flow and Protection of a Limited Bus Grid System with Injected Solar Power

Nader Barsoum, Chai Zen Lee

Department of Electrical and Computer Engineering, Curtin University Sarawak, Miri, Malaysi.
Department of Electrical and Computer Engineering, Curtin University Sarawak, Miri, Malaysia.

DOI: 10.4236/epe.2013.51008                

Abstract

In recent years, injection of renewable energy such as solar power into the power grid is increasing. However, inclusion of large-scale intermittent-type renewable energy requires better management in proper understanding of grid’s variable characteristics and its protection systems. In this paper, the investigation on overvoltage issue is illustrated. Overvoltage in distribution feeder occurs when large amount of solar power is injected at low power demand. Another investigation is on false operation of overcurrent relays due to reverse power to the 33 kV loads. The potential solutions to the two issues are illustrated in the small-sized power grid system using bi-directional inverters on AC buses in charging battery banks and adjusting the relay current settings. The benefits of solar power injection are illustrated whereby output power from generators is decreased and transmission losses are reduced. Electrical Transient Analysis Program (ETAP) was used for investigations.

Keywords

Grid Systems; Solar Power; Overvoltage; Overcurrent Relay; Bi-Directional Inverter; Relay Current Setting

Conflicts of Interest

The authors declare no conflicts of interest.

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