Abstract:
There are many companies in Ethiopia that are ever-growing fast. One of the leading
companies is Ethiopian telecommunication which provides a quality telecom service to
citizens and supports the development of the country. To ensure this quality service, one of
the most driving agents is electrical power which can be generated from different sources of
energies like Diesel Generator (DiG=20KVA), Main Grid (MG) and Photo Voltaic
(PV=11.5kW) generator along with the backup Battery Banks (BB) in the form of hybrid
power system with 48VDC volt system for a typical site of GINDE WOYN MW. Doing such
type of power combination may secure the power supply to the required load demand but still
this hybrid energy system has its own problem on its controlling system. Since the company
operate its DiG automatic with the MG without considering PV power and the backup
battery. These forces the company costs more for diesel fuel as well as billing for Ethiopian
Electric Utility Company (EEU). Hence, this thesis is going to solve the problem by applying
Fuzzy Logic Controller (FLC) based Energy Management System (EMS) for power source
selection. The proposed EMS prioritizes the power source according to the availability of
each sources unit. The first selection of FLC is the renewable energy source of PV power, the
second selection is backup battery within its upper and lower limit of SOC of the battery and
the third selection is the mains grid if any lastly the diesel generator if no mains available.
FLC is used to choice among different power sources in a hybrid system. Maximum Power
point tracking (MPPT) based on artificial neural network (ANN) for PV system to maximize
output power of the PV generator under different environmental conditions such as solar
irradiance and temperature. Since renewable energy is green unlike diesel generator, it doesn't
emit carbon dioxide which causes global warming. Modelling all existing components like
solar panel, diesel generator, converters, grid power, different MPPT trackers and simulations
have been executed with Matlab/Simulink software. Simulation result shows the ability of
EMS based on FLC to optimize the system performance and certified the effectiveness of the
proposed system which achieves by reducing 72.92% fuel consumption and 41.67%
commercial billing for EEU also.