Improvement of voltage levels of medium voltage distribution networks: a case study of Nordic feeder, Dar es Salaam

Tanzania Electric Supply Company Limited (TANESCO) is the sole electricity utility company in Tanzania supplying electricity to Tanzania consumers, its core activities being to generate, transmit and distribute electricity to consumers. However, in the course of distributing electricity to its customers, the company is facing many challenges including overloading of the Medium Voltage distribution networks, poor voltage regulation, and high losses and some customers operating at low power factor. TANESCO as well as other Utilities around the globe, recognize that the objective of the distribution network is to distribute power at voltage levels defined in general conditions of power supply (i.e. within the defined voltage regulation) for which appliances and equipment will operate. In this research, a load flow study methodology including data collection, network modeling, designing procedures, testing the load flow model itself, PSS/E (Power System Simulation for Engineers) software for load flow study and reactive power compensation methods are presented. Two scenarios for load flow study were conducted on the medium voltage (33 kV) network and results are presented i.e. simulation of the existing distribution network and simulation of the distribution network after improvement on the network was done. TANESCO can use the load flow study methodology presented in this research for operational purposes, and planning for future system expansion, including the use of Shunt capacitors in its MV radial distribution networks suffering from poor voltage regulation.