CVI POWER




Casey Cook


Ivan Hernandez


Bill Vlahos

Objective

Design and construct the Power Electronics aspect of a low-cost, high efficiency energy conversion system. A 10 KW unit is to be realized based on a 1.5 KW prototype developed by CVI Power.

Abstract

Since the dawn of the industrial revolution, modern societies have relied heavily on some form of fossil fuel (coal, petroleum, etc.) to satisfy their energy needs. The majority of this energy has been converted into electric power, which is then distributed to homes and industries around the world. This excessive exploitation of natural resources has led to shortages of fossil fuel and their eventual depletion, indicating a strong need for developing ways that will focus on harnessing alternative sources of energy, such as wind and solar. In order for these alternative sources to be used effectively, they have to be converted to forms that can be generated and distributed efficiently and reliably. Inverters convert power from DC into AC so as to be used in modern electrical systems with minimal effort from the manufacturer's standpoint. Our team is part of a larger interdisciplinary group representing the University of Texas at El Paso for the Department of Energy's "2001 FUTURE ENERGY CHALLENGE" competition.

Method of Completion

The project is broken down into three major modules:

1. DC to DC Converter Module: The DC to DC Conversion Module will step up and regulate the voltage received from the input renewable energy source. The basic topologies to be used is a Cuk converter.

2. Power Electronic Switching Module: This is where the DC to AC inversion will take place. IGBTs are used as the switchesfrothis module. The interface between the power electronics and the control part of the module is an optocoupler. The input to thre IGBTs is passed through this chip and while the overall shape of the pulse is not affected,the amplitude will be sufficiently increased. This added boost to the voltage is obtained by connecting a floating power supply at the output of the optocoupler. In addition, an RCD charge-discharge snubber circuit is placed in the circuit to protect the switches from transients.

3. Output Filtering Module: A low-pass fourth order filter configuration has been implemented for suppressing higher harmonics that could potentially distort the output signal,significantly reducing the THD under 5%.

Issues

The low-cost high efficiency power inverter has been succesfully implemented. The cost was kept under $500 and the split single phase output was realized. All the modules were succesfully integrated and have been able to deliver power to the load appropriately.

Main Block Diagram

Inverter Model for Reverse Engineering

Conclusion

The functionality of the project has been demonstrated succesfully to the faculty of the ECE department. All the initial proposed modules of the design have been succesfully implemented.

HIVE A NICE SUMMER!