Combination of Existing Transformer and Newly Placed Transformer for Optimal Electric Power Distribution System

Electric power is one of the basic human needs. To fulfil the consumer’s power requirement, the electricity supplier and provider need an economical and reliable distribution system. Nowadays, a transformer has been installed in the power distribution system, and if it is moved, it will need a high replacement cost. Therefore, the development of the power distribution system will not change the existing transformer location. However, the current transformer capacity does not adequate to provide the electricity requirement; therefore, newly placed transformers are required to support and provide the needs. This research aims to determine the optimal combination of existing and newly placed transformers to provide a reliable and economical power system. The reliable power distribution system is gained from the shortest power connection distance and low power loss distribution system. The most economical power system is gained by finding the transformation location that produces the lowest cost for power distribution installation, system installation, and lowest transformer losses. The optimal condition is calculated by a genetic algorithm respecting the voltage limit regulation. The result combines existing transformers and newly placed transformers in PT. PLN (PERSERO) Rayon Dolok Masihul Sumatera Utara is the transformer coordinate and capacity, the transformer load combination, and the minimum investment cost.