AC Propulsion Introduces the AC-150 Gen 2

AC Propulsion Introduces the AC-150 Gen 2:

A Powerful, Efficient Electric Drive System with New and Unique Features

December 12, 2001
Sacramento, CA

AC Propulsion introduced the AC-150 Gen 2, a new drive system for electrically-propelled vehicles, at the Electric Transportation Industry Conference today in Sacramento. The original AC-150 is the 200 horsepower (150 kW) drive system that has set new standards for performance and efficiency since it was launched amid much fanfare and tire smoke in 1994. Since then, the AC-150-powered EVs have proved that electric vehicles can be exciting as well as emission free. In AC Propulsion's tzero prototype, the AC-150 provides the power to accelerate faster than Ferraris, Lamborghinis, and Porsches yet delivers the efficiency of a Honda Insight. Two AC-150s powered Ed Dempsey's White Lightning as it set the EV land speed record at 254 mph.

The new AC-150 Gen 2 gives up nothing to its forebears in the performance department, but it embodies new functions and design improvements from the fertile mind of Alan Cocconi, AC Propulsion's Founder, Chairman, and Chief Engineer. "We've been building, selling, and driving the AC-150 since 1994, so when we started work on Gen 2 in 1999, we had a wish list of new features and changes we wanted, and along the way, we had some other brainstorms, so the end result is packed with improvements both major and minor," Cocconi noted. "The Gen 2 is a smaller, lighter drive system that provides more features for the EV driver and creates new opportunities for the EV manufacturer."

One new feature in particular stands out as a potential breakthrough for electrically propelled vehicles the AC-150 Gen 2 has a bidirectional charger. In simple terms, this means that the charger can reverse the conventional charging process and send 60 Hz AC power, efficiently and safely, out from the vehicle. With a bi-directional charger and appropriate control and communications systems, fleets of vehicles can serve as active elements in the power grid. AC Propulsion is in discussions with the California Air Resources Board (CARB), the California Independent System Operator (Cal ISO), the California Energy Commission (CEC), the South Coast Air Quality Management System, (SCAQMD), Electric Power Research Institute (EPRI), other agencies, academics, automakers, and utilities about the potential for, and barriers to, what has come to be called vehicle-to-grid (V2G) technology.

The bidirectional charger also has smaller scale but more immediate benefits. By discharging into the grid, electric vehicles can perform a self-diagnostic battery check to evaluate the capacity and state of health of the battery pack. EV owners know that accurate knowledge of battery capacity is important but until now, a discharge test was difficult and time consuming. Some EV dealers had to resort to assigning an $80/hour technician to drive an EV around the block continuously to see how far a suspect battery would go. With bidirectional charging, the whole test can be accomplished at night, at the customer's home, and the battery can then be recharged to full by morning.

The bi-directional charger does not need to be connected to the grid. In stand-alone mode it allows the vehicle to power appliances and equipment ranging from lights and computers all the way up to refrigerators, air conditioners, power tools, arc welders, and whole houses. With a battery EV the duration of power is limited to several hours by the battery capacity, but the bidirectional charger can be used on hybrid and fuel cell vehicles too. By converting onboard fuel energy to AC electricity, such vehicles can provide remote power at worksites and backup power during blackouts. "Hybrid and fuel cell vehicles can generate power cleanly and efficiently while they are parked" said Tom Gage, AC Propulsion President. "The engine or fuel cell will just be sitting there, so it makes sense to put it to use. With automotive emission control technology and economies of scale, vehicle-based power generation can operate more cleanly and cost effectively than many other distributed generation resources. We are just starting a project to build an HEV that will use a Gen 2 drive system to demonstrate this.

"Besides V2G, stand alone power, and clean generation, there is one other capability of the bi-directional charger energy that we expect will eventually come in handy", Gage said. "With a bidirectional charger, we can charge one EV from another. In ten or 15 minutes, we can transfer enough charge to get the stranded vehicle to a charge station under its own power."

The new AC-150 Gen 2 retains the 150 kW peak traction power and the 20 kW charge power of the original AC-150 but it is 30% smaller and eight pounds lighter. The AC-150 power electronics unit (PEU) includes the traction inverter, the charger, a 100 ampere 13.5V DC power supply, the battery contactor assembly, and the high voltage power interface for hybrid and accessory connections. "Looking at all of the components, we think this is the smallest complete power system available for a full function vehicle, and it's all in one box" Cocconi stated, "and when you look at power density, kW per liter, there is nothing else that comes close"

Along with the smaller package, the Gen 2 uses improved water-tight connectors for all signal inputs and a quarter-turn twist lock connector for the battery connection to the PEU. A new contactor control system improves servicing safety by providing user-friendly battery connect/disconnect procedures. Digital control logic allows greater flexibility in adapting the AC-150 to any induction motor for variety of applications including light truck and medium duty applications. The new control system is inherently compatible with CAN and other digital control protocols used by auto manufacturers.

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 electric propulsion systems with integrated grid power connection capability. AC Propulsion has patented several key technologies for electric drive vehicles, and is developing technologies and business models for vehicle-to-grid systems that will transform the automotive and distributed power generation industries.