poulsen hybrid conversion kit

The Poulsen Hybrid system attached to a Jetta. Click to enlarge.

Poulsen Hybrid is developing a conversion kit that will add through-the-road plug-in hybrid capability to conventional vehicles by externally mounting electric motors onto 2 of the wheels. The motors are normally applied to the rear wheels, in the process converting a FWD car to all-wheel drive, but the system works with rear- and all wheel drive vehicles as well, according to Poulsen.

The system will be available in kit form and could be installed by individuals (do-it-yourself, DIY) in a day, although Poulsen says that it has not decided whether or not to offer the kit that way, due to potential liability issues. Poulsen, which is competing for the Progressive Insurance Automotive X-Prize, plans to offer the system through a network of authorized installers.

The Poulsen PHEV conversion system. Click to enlarge.

The system is based on the premise that 10-15 hp is required to propel a compact or mid-size automobile along a level road at a steady 60-70 mph, and that a relatively small amount of electric power would be able to cope with 70-85% of normal driving, only aided by the combustion engine during start up and when extra energy is required for acceleration and hill climbing.

The Poulsen system, which supports regenerative braking, uses two 5 kW (7 hp) Permanent Magnet, Axial Field (PMAF) motors developed by Alpha-Core, Inc. The disk-shaped on-wheel motors are installed onto the original wheels by means of adapter plates, which are bolted onto the back of special wheel lug nuts.

The stator is prevented from turning by means of a torque bar, which extends from the outside center of the motor to connection fixture situated directly behind the rear wheel and attached to the fender or rear quarter panel. Power supply takes place via power cables extending through a channel in the bar/conduit to the motor controllers and battery pack located in the trunk. Addition of the Poulsen Hybrid system does not touch existing brake, steering and suspension systems.

The controllers in first generation systems are programmed for torque control and are not connected with the original accelerator pedal. The armature current and thus amount of superimposed torque and the brake torque are controlled by potentiometers located in a pot box which is connected with the power supply in the trunk by a 10 ft. cable. A toggle switch turns the system on and off.

Poulsen is currently using a lead/acid deep cycle battery pack comprising six 12V 120 Ah batteries with a 72V/10A on-board charger. The company expects to have a 4.3–4.5 kWh lithium-ion battery pack available this year.

The company has not yet tackled the issue of Department of Transportation (DOT) approvals. Poulsen says that it will post third-party performance data for the hybrid system when it becomes available.

In June, Poulsen announced that it was proceeding to build a pilot series of 500 motors (250 kits), based on the performance of its prototypes. Part of the current effort is focused on the development of manufacturing equipment for the motors, torque arms and model-specific components.

The company said that it hopes to reach a capacity of 100-150 systems per day late in 2008. Although the initial motor design was for light vehicles, the company is working on two more powerful versions suited for SUVs and pickup trucks.