October 19, 1999
San Dimas, California

A new conductive charging system will make life easier for electric vehicle (EV) drivers. Using high-power AC charging, the innovative system speeds up the charging process and reduces the cost of charging equipment. EVC3, the Electric Vehicle Conductive Charging Coalition, will support standardization of high-power AC charging by the Society of Automotive Engineers (SAE). EVC3 members include DaimlerChrysler, Ford, Honda, Mazda, Volkswagen and Volvo as well as EV component and infrastructure suppliers.

AC Propulsion, Inc. of San Dimas, CA, conceived the new system because its Reductive(tm) electric vehicle chargers can use more power than standard Level 2 charging equipment can supply. Working with infrastructure suppliers EVI, Inc. and Avcon Corporation, AC Propulsion has developed, tested and demonstrated a working prototype.

"We call high-power AC charging 'Level 2+' because it provides the power of Level 3 charging with the simplicity of Level 2", said Tom Gage, AC Propulsion business manager. "We build high-power chargers into our cars because we've found that faster charging really improves EV convenience. With Level 2+, EV drivers can fully utilize our charger. A 30 minute charge can provide 50 miles of range, so EV drivers can charge quickly and go on about their business. Since Level 2+ equipment will not be expensive, there should be plenty of places to find it. Extensive daily driving, 200 miles or more, even with low-cost lead-acid batteries, will be possible. This is a real cost and convenience breakthrough for EVs."

Level 2+ charging equipment will be displayed and demonstrated at the North American Electric Vehicle & Infrastructure Conference (NAEVI) in Atlanta, Georgia, Nov. 17-19, 1999.

"EVI will be at NAEVI to demonstrate high-power AC charging with a modified version of our EVI ICS-200B charge station", said Mickey Oros, president of Electric Vehicle Infrastructure, Inc., the nation's largest supplier of conductive charging equipment. "Faster charging is a big plus for the customer. We are working hard to make it happen."

High-power AC charging represents a promising new direction for EV charging infrastructure. Until now, high-power charging required offboard chargers to convert line current (AC) to direct current (DC). Now, EV engineers are starting to integrate this function into the car, so the offboard charger, and its cost, are eliminated.

According to Craig Toepfer, a Ford EV infrastructure development engineer, "Infrastructure cost is a big barrier to EV commercialization. Now, with high-power AC charging, that barrier is dramatically reduced."

Only conductive charging equipment can economically provide the faster Level 2+ charging. Inductive charging equipment, which requires a complex offboard charger, is less adaptable to high-power charging for cost reasons.

Stuart Johnson, principal engineer, Volkswagen environmental staff , noted, "Volkswagen likes conductive charging for EVs because it allows the charger to be integrated with the drive system. This reduces vehicle cost and weight and it can handle fast or slow charging, whatever is available. Level 2+ is the key to making fast charging a reality for our customers and we think that is what they will want."

Level 2 is the official designation for EV charging equipment that provides up to 7 kW of electrical power for EV charging. SAE's Conductive Charging Standard J1772 specifies safety, reliability and convenience features for conductive Level 2 charging equipment. Level 2+ uses the same designs and control specifications as Level 2 but upgrades components and logic to supply up to 75 kW of charging power. Level 2+ can still supply lower power to existing EVs like Honda's EV Plus and Ford's Ranger EV. Similarly, vehicles built with Level 2+ capability will be able to use existing Level 2 charging equipment. This backward and forward compatibility will sustain the momentum of EV charging infrastructure growth.

The proposed Level 2+ configuration is an open standard intended to promote EV acceptance and use. AC Propulsion will collaborate with automakers and infrastructure suppliers to revise SAE Standard J1772 to accommodate Level 2+. Tom Cartwright, president of Avcon, a leading supplier of EV charging couplers, says, "Level 2+ builds on the existing standard conductive coupler. Avcon plans to support Level 2+ with cable coupler assemblies and complete interface boxes."

AC Propulsion is a California corporation dedicated to creating electric vehicles that people want to drive. Founded in 1992, the company develops, manufactures and licenses technology for high performance electric vehicle drive systems. AC Propulsion has patented several key technologies for electric vehicles, including Reductive charging. Reductive charging integrates a high-power battery charger into the vehicle's motor drive electronics, providing high-power charging with very low incremental cost.

Technical information is available from www.acpropulsion.com (link to technical details).