Delphi's new 800-volt SiC inverter to reduce EV charging time by half

by Autocar Pro News Desk , 17 Sep 2019

Electronics company Delphi Technologies has started commercial production of an 800-volt silicon carbide (SiC) inverter, which is one of the key components of highly efficient next-generation electric and hybrid vehicles.

The new inverter enables electrical systems up to 800 volts, significantly extending EV range and reducing charging times by almost half when compared with today’s state-of-the-art 400-volt systems.

The new technology supports multi-voltage platforms, which the company says is an evolution of its high-voltage inverter and builds on its over 25 years of vehicle electrification experience. Delphi Technologies 800-volt inverter uses silicon carbide MOSFET semiconductors (silicon carbide-based metal-oxide-semiconductor field-effect transistor wide band gap technology). The company recently secured a massive $2.7 billion (Rs 19,305 crore) order from a premier OEM for volume production of this technology over eight years. A official launch is expected in 2022, which will initially be for a high-performance vehicle operating at up to 800 volts.

Recently, the company announced that it is partnering with US-headquartered Cree, which is one of the leading players in the field of SiC semiconductors, that enable the next-generation of EVs to drive longer distances, have faster charging times and improved efficiency. Delphi Technologies inverters will utilise Cree’s Wolfspeed silicon carbide-based MOSFETs.

The company says as per IHS estimate up to 45 percent of global vehicle production will be electrified by 2025, with around 46 million electrified vehicles being sold annually, rising to up to 57 percent by 2030 (around 62 million vehicles annually). Inverters are one of the highest-value electrification components and their efficiency has an industry-changing impact on many aspects of vehicle performance.

Richard F Dauch, CEO, Delphi Technologies said: “Doubling the voltage from today’s typical 400 volts brings a substantial range of benefits, both for the vehicle user and for the vehicle manufacturer. We have designed this technology to simplify vehicle manufacturers’ multi-voltage strategies as they extend their electric and hybrid vehicle ranges.”

At the heart of the new Delphi Technologies inverter is the company's patented Viper power switch, which combines high levels of integration with unique double-sided cooling. These critical features allow the company to develop inverters that are 40 percent lighter and 30 percent more compact than competitor inverter technologies.

The latest addition to the Viper power switch range replaces conventional silicon with SiC, a high band gap semiconductor that allows very fast switching and can operate at even higher temperatures.

“The faster switching alone will allow faster, more compact and lighter motors that offer great efficiency and greater range. That’s in addition to the many benefits of moving to 800 volts," explained Dauch.

The company says with the new inverter operating at 800 volts, vehicle engineers will now have additional flexibility to optimise other powertrain systems. The options include more range or a smaller battery; ultra-fast charging or smaller, lighter, cheaper cables; and greater harvesting of vehicle kinetic energy when braking, further extending vehicle range.

The new SiC Viper power switch fits into the same inverter package as the current silicon switch, reducing engineering costs associated with a technology change and simplifying the design of multiple vehicle performance options. Delphi Technologies says its integrated DC/DC converter and inverter already provides significant savings to OEMs.