Delphi Team Receives U.S. DOE Funding to Help Lower Cost of Power Electronics for Hybrid Electric Vehicles

Delphi aims at a 50% cost and size reduction in electric propulsion inverters


KOKOMO, Ind., — Delphi Corporation announced that it has been selected by the U.S. Department of Energy (DOE) to lead an industry-government team to develop the next generation propulsion inverter for hybrid vehicles. The new smaller inverter is lower cost and will be used on the next generation high-efficiency hybrid electric vehicles (HEVs) and next generation “plug-in” hybrids (PHEVs). In the longer-term, the inverter will be used for fuel cell vehicles (FCVs).

Hybrids and next generation “plug-in” hybrids help conserve energy reserves in reducing emissions of greenhouse gases and other air pollutants. The DOE and Delphi view this particular project as a key element of a strategic, public-private partnership to achieve the lower-cost technologies needed for these advanced vehicles to become more broadly accepted in the U.S. marketplace.

The Delphi-led research and design team will contribute $3 million and receive $5 million in funding from the DOE, resulting in an $8 million project, seeking to reduce the cost and size of the inverter for electric propulsion systems by 50% or more.

“We are pleased to have the opportunity to work on this exciting project,” said Thomas Goesch, Delphi managing director of the Power Electronics PBU. “We have assembled a team of highly qualified industry leaders and national laboratories to identify and develop the key technologies needed for an electric propulsion inverter that meets or exceeds the DOE performance and cost targets.”

The primary team members for the project include: Delphi for the inverter design, packaging, thermal management, mechanical integration, build, test and assessment of cost to manufacture; Dow Corning and GeneSiC for silicon carbide-on-silicon power semiconductor devices; General Electric for high-temperature thin-film DC buss capacitors; Argonne National Lab for ceramic capacitors; and Oak Ridge National Lab for characterization of power semiconductor devices, modeling, simulation and evaluation of alternative inverter topologies, and system testing.

Propulsion inverters provide phased AC (Alternating Current) power for hybrid vehicle traction motors and generators, as well as auxiliary pumps and drives. The propulsion inverter enables precise control over electrical power flow from the battery to the electric motor. One or more electric motors can be combined with another power source like a gasoline or ethanol engine, an engine-generator, or a fuel cell to propel the vehicle at higher efficiency than conventional engine technology.

In addition to reducing the cost and size of the inverter system, the Delphi team is taking on the challenge of enabling the system to operate at normal engine coolant-loop temperatures of 105-120° C to help reduce other system costs and the space needed to cool today’s inverters.

“This will result in development of inverter building blocks that will be readily scalable to a wide range of power levels, enabling the necessary economies of scale for lower cost,” said A.J. Lasley, Delphi chief engineer for advanced HEV and powertrain electronics.

“Clearly, this is the type of project that will help the economy of Indiana as well as the entire U.S.,” said Paul Mitchell, policy director for economic development, workforce & energy for Indiana’s Governor Mitch Daniels,“ particularly by reducing everyone’s energy costs, but just as importantly by stimulating growth of the expertise and U.S. industrial base for advanced ’green’ technology. Delphi has been a pioneer in power electronics and is building on this legacy by developing the next generation of energy efficient technologies needed to accelerate production of tomorrow’s vehicles today. We are thrilled this innovative work is being led here in Indiana and in partnership with many others throughout our nation, and are hopeful the discoveries generated will lead to new high-tech jobs.”