DESIGN AND CONSTRUCTION OF 5KVA MODIFIED SINE WAVE CONVERTER
It is a statement of fact that power plays a significant role in our daily life. However, Nigeria as a developing country has a lot of challenge in the area of electric power supply. The challenges include inadequate of electric power generating which causes instability of electric power supply in Nigeria. This problem is the course of low productivity in Nigeria, which highly affects our economy. In the above challenges, several efforts have been made to over come this challenge of power instability of electricity, but present outcome are difficult or rejected for its high disadvantages, which as generating set heavy duty diesel engine, solar panel, etc when this alterative source of energy for electric power supply are presented, it create another challenges such as fueling, replacement of parts and producing pollution all over the area.
The inverter system is one substituted for these lapses seen in the above mentioned alternative sources. The inverter system is an electronic system that converts stored chemical energy in battery into electrical energy. Therefore, an inverter system is an electronics circuit that convert Direct Current (DC) to Alternating Current (AC). The capacity of an inverter depends on the application of the appliances and the area by which appliances are to be used. For the purpose of being clearly, the inverter as we are discussing it here may have another scope, but is purely designed for domestic use with its maximum capacity of 5KVA is about 4000watts. It serves as UPS for where there is power failure and also serve as a generating source where there is no power supply form the national grid.
Introduction of this project is all about power inverter system.
Power inverter system is a device used to convert a direct current (d.c) supply into an alternating current (a.c) power supply by an invertion process.
Power inverter system is used as an uninterrupted power supply to where there is constant power outage from the national grid.
It is also used as a power source where there is no power from the national grid.
The power inverter system is used to supply power to our electrical appliances at home and also in our industries, it is of different types and categories. The types are.
i) Pure sine wave power inverter
ii) Modified sine wave inverter
iii) Square wave power inverter etc.
While they are categories as
iii) 1000VA = 1KVA
iv) 1500VA = 1.5KVA
v) 2000VA = 2KVA
vi) 5000VA = 5KVA etc
6.1 THE PROJECT BACKGROUND
This project is basically on power inverter system which we use to convert D.c power supply to a.c for home and industrial use.
Development of power inverter system became necessary because of the power failure that occurs sometimes form national power supply.
For the fact that we are making use of electronics and electrical devices that depends on Power supply for there operations, then we go for an alternative source of power for the constant operation of these devices.
The devices are
ii) Television sets
iii) Radio sets
iv) Electric lamps
vi) Refrigerators etc
The process through this inverter converts D.C to A.C ios called invertion.
This inverter system could be used in conjuction with solar energy by using solar panel or solar module.
Inverter is also vital part of uninterrupted power supply system, therefore when A.C mains goes off the inverter will automatically pick on for the replacement of the power failure from A.C mains. It can also be use where there is no power supply at all.
This invert convert it D.C to A.C by the help of electronics switch called transistors , the transistors make use of oscillating signals that come form the oscillator for its switching. The oscillating signals is the frequency of the inverter.
6.2 AIMS AND OBJECTIVES OF THE PROJECT
i) The purpose of this project is to design and construct a 5KVA power inverter system for the supply of A.C power to serve loads of about 400Watts.
ii) The purpose of this project is to ensure that we produce an inverter system to maintain a constant power supply in our various homes and industries.
iii) The aim of this project is to modelize the old pertain of inverter and introduce some automatic circuit that can help in a different device apart from inverter.
iv) The aim of the project is to ensure that the lectures and other practical works we have been attending in this school does not go in vain. Therefore to give out a good output form what we have been practicing since.
6.3 SCOPE OF THE PROJECT
The design and construction of this power inverter undergoes the process of sourcing out of different components for the circuit construction and designed, also the transformer winding and battery.
All this component sourced were fixed according to the circuit diagram on a vero board and the fixed components were all tested to ensure a good result from them.
The circuit was completed by the transformer where the conductor winding for stepping up of voltage and clamping of lamination to air tight condition were done.
After all these the transformer was tested and it was given out a good output with specified rating of 5KVA, which is equal to 4000W or 4KW due to power factor.
The scope of this project is also gets to the testing of the entire system after interconnection of battery, transformer, coolant fan and the circuit of the inverter.
It is also tested after packaging the entire circuit in one metal construction case with vent that will ensure the inlet of air for coolant, especially the mosfet and transformer that generate heats during operation period.
It is also fixed with fires for easy movement from place to place.