DESIGN AND IMPLEMENTATION OF 2.5KVA SOLAR INVERTER

ABSTRACT In Nigeria presently, electrical power generated presently is grossly insufficient in terms of meeting the power demand in the country. Presently, the Electrical Electronic Engineering department depends solely on the central diesel generator for the School of Engineering building which comes on at anytime and goes off at unexpectedly daily. Therefore there is need for alternative power supply system in order to reduce over-dependency on the utility grid. This project proposes a 2.5KVA hybrid power supply system for powering of the departmental classes and laboratory. Based on load calculations for the department and laboratory, the system requires a 2.5KVA power inverter which converts power from 8 units of 24V/200AH deep cycle battery into AC power, 6 units of 300W solar panel for recharging the batteries through a 45A solar charge controller. The design procedure adopted includes various sizing calculations used to determine the required battery capacity, power rating of the solar panels and the inverter capacity. Also, an incremental approach was adopted for achieving the required inverter capacity. Based on this approach, an initial 1500W inverter with 24V/100AH battery capacity and 560W solar panel array were installed to drive the computers and other appliances in the department. Subsequently, another 1500W is expected to be installed in the future to take care of future load in excess of 1500W. The test results show that it took about two hours (2hrs) to discharge the battery under 761W load and five hours (5hrs) to fully charge back to 27.2V. It was observed that the intensity of the sunlight had great impact on the rate of charging of the battery. The results show that this solar installation can be used to compliment power supply for the department and laboratory especially during power outages and downtimes of the central generator.