A researcher at Indiana University-Purdue University Indianapolis (IUPUI) has invented a new class of power inverter that could lead to cheaper and lighter traction motors and power electronics for EVs.
Power inverters are a key component of EVs, as well as related technologies such as solar power and battery storage. Current inverters with multiple switching transistors generate limited voltage levels, are heavy, generate unwanted harmonics (voltage frequencies) and require filters to reduce harmful effects to the electric grid. Professor Afshin Izadian has invented an inverter that uses a single switching transistor and generates infinite-level voltages, an innovation that could make inverters cheaper, lighter and more efficient.
“The thrilling moment of any research is when your thoughts, designs and implementations come out right and you reach the goal,” Izadian said. “An on-demand change of voltage polarity might not seem very exciting, but it becomes increasingly important if you can accomplish it while maintaining desired voltage amplitudes.”
In a creative moment at his lab bench, Izadian began reconfiguring an inverter circuit and discovered a new technique to create infinite voltage levels and invert the voltage polarity of power circuits, an insight that led to the discovery of other circuits and controllers for high-power inverters with lower switching loss, higher voltage performance and lighter reconfigured circuits. Unwanted harmonics are greatly reduced, which means that car manufacturers can reduce the size and insulation of traction motors and power electronics, so that EVs can be made cheaper.
Izadian’s work is under review by a technical journal, and he has several patents pending. Several companies have shown interest, and he hopes to have products ready for the marketplace in as little as three years.