- Professor Afshin Izadian
Professor Afshin Izadian of IUPUI's School of Engineering and Technology has done what many thought impossible with the invention of a single-switching transistor power inverter. This discovery comes at a crucial time, when green products are not only desired but required to meet the energy needs of the future.
Izadian's research could prove to be a major step in improving the design and application of green energy technologies, such as solar power and electric vehicles.
Today, most homes and businesses run on alternating current (AC). However, not all electricity sources create alternating current electricity. Some power sources, including batteries and solar panels, create direct current (DC) electricity. This has some industrial applications, but it cannot power homes and businesses. However, direct current electricity can power homes and businesses indirectly if it is converted to alternating current with a power inverter.
Traditional power inverters have at least two switching transistors. While transistors are essential in power inverters, they are cumbersome and inefficient. Each transistor can only output a fine range of voltages, as well. Furthermore, even with specially designed filters, power grids are damaged each day by transistors, leaving much to be desired.
Izadian's new class of power inverter design uses just one switching transistor, much lighter, cheaper and more efficient than traditional multiple-transistor designs.
Izadian came up with his creative transistor design while studying voltage and polarity creation in inverters at IUPUI. In his lab, he randomly reconfigured an inverter circuit. As a result of the reconfiguration, he discovered a new inverter that allowed for infinite voltage levels and the inversion of the power circuits. Also, by-product harmonics, which result in inverter inefficiency, present in all transistors, are reduced in Izadian's design.
"We have a working prototype [of the design]," Izadian said. "It is low power because it is funded by the university." Real-world transistors will be powered at a higher level. The transistor at IUPUI is being used for test cases because the engineering it is using is very new to the scientific community. Izadian and his team also are developing several different circuits for a variety of applications. Having a design for each specific application will only improve transistor efficiency and productivity.
The design is currently under review by a well-known technical journal and many experts in engineering and the energy industry are showing interest.
If the scientific and engineering communities embrace the technology, it may be used in multiple fashions to improve many products that require the conversion of direct current electricity to alternating current electricity. For example, his design could potentially downsize the power components of electric vehicles, resulting in smaller and lighter vehicles. Traction motors in electric vehicles may be less expensive with Izadian's design. And it might have applications in manufacturing robots and green power production sources such as solar panels.
Pending recognition from the scientific community, Izadian's design is ready for manufacturing and wide-scale use. He also is waiting for approval of multiple patents and for additional funding to further develop his product. He estimated the inverter could be on the market within three years.
Izadian's design is a step forward on the long and complicated road to developing technologies to address the energy crisis. Cultural and social changes in the U.S. are needed to maximize the usefulness of Izadian's design, experts say.
"Even if we have an inverter that is 100 percent efficient, we will not solve the problem arising from our energy addiction," said Giri Venkataramanan, a professor in the Department of Electrical & Computer Engineering at the University of Wisconsin-Madison, noting that broad social change is necessary to solve our energy dependence.
"Only cultural shifts can close the gap."
While his breakthrough is big for his own research, Izadian recognizes it is important for the university, as well.
"This kind of breakthrough means a lot to [IUPUI]. It shows our participation in green energy," Izadian said.
In particular, his design further highlights the work at the Richard G. Lugar Center for Renewable Energy on IUPUI's campus, where Izadian is a research faculty member. The center, opened in 2007, focuses on the research and development of green power generation technologies.The center already has made great strides in fuel cell, waste-to-energy and other green technologies.
"We are delighted with Dr. Izadian's work and the possibility that his inverter can impact the renewable energy market," David J. Russomanno, dean of IUPUI's School of Engineering and Technology, said in a news release. "His efforts are the quintessential example of the cutting-edge research that enhances the school's image and reputation and allows us to compete in the renewable energy arena."
A bit about Izadian
Afshin Izadian's recent inverter discovery follows many other impressive accomplishments. He has participated in more than 50 scientific publications and journals and contributed a chapter to CD Proceeding on Electro-Information Technology, a book released this year.
Currently, Izadian is an assistant professor at the Purdue School of Engineering and Technology at IUPUI and a research faculty member at the Richard Lugar Center for Renewable Energy.
He said his ventures into the field of electrical engineering began in Iran, where he received a master's degree in electrical engineering from the Iran University of Science Technology in 2001. Seven years later he was awarded a doctorate in electrical engineering from West Virginia University. He pursued his postdoctoral research in 2009 at UCLA, where he began to broaden his research to include control of renewable energy systems and power converters, nonlinear controls and fault diagnosis, microsystems, MEMS, digital microfluids and energy conversion.
"I had the opportunity of applying my controls engineering knowledge to microfluidics as a postdoctoral researcher at the Department of Chemistry and Biochemistry at UCLA," Izadian said. His research at UCLA and other institutions has exposed him to multiple science and engineering disciplines and has made him one of state's leaders in renewable technology research and development.
Izadian explained that his fascination with tracking controllers inspires him to conduct his research. "Adaptive and other types of controllers that operate under system uncertainties are my favorites," he said.
Most of Izadian's long-term research goals revolve around his work with his power inverter. "We are currently working on the modeling and system operation analysis phase," Izadian explained. "In [the] future, I would like to complete the design of the inverter and its controller and use it for high power application." He plans to upgrade his lab's power inverter so it can operate at higher levels, closer to what he and his team will need in the field.