Continued from Panasonic to Start Production of EV Driving System in 2018 (1)

Small size, light weight, high expandability

The ePowertrain Platform has two major features. First, its size and weight can be reduced by eliminating wiring, etc, compared with a system made by combining discrete components. Compared with the previous product, for which Panasonic combined discrete components, the new system has about 50% less volume and about 30% less weight. Also, the company improved efficiency from 86% to 91%.

A comparison between the previous system, for which Panasonic combined discrete components, and the new system. In this case, two motors are used. In the case of the new system, the EV uses one unit of the Integrated Unit and one unit of the Expansion Unit.

Second, the expandability of the system was improved. By using an in-vehicle charger, DC-DC converter, inverter, junction box and motor as "Integrated Unit," "Expansion Unit" consisting of an inverter and motor is added in accordance with the output required by an EV to which the system is applied.

For example, an electric motorbike uses one unit of the Integrated Unit, and a four-wheeled compact EV uses one unit of the Integrated Unit and three units of the Expansion Unit.

A mock up of the next-generation Integrated Unit (blue) used for an electric motorbike

A mock up of the the next-generation system used for a compact EV. It uses one unit of the Integrated Unit (lower right) and three units of the Expansion Unit.

Panasonic also started the development of a next-generation product, which is even smaller and lighter in weight than the new system, aiming to commercialize it in 2020-2025. For the next-generation product, the company aims to halve the volume while slightly increasing output.

For size reduction, Panasonic plans to reduce the sizes of passive components by increasing the switching frequencies of charger, DC-DC converter, etc as well as to increase motor rotation speed. The rotation speed of the new system's motor is higher than 10,000rpm, and its torque is several tens of newton meters, Panasonic said.

Original Japanese article