Modular concept can be used as zero-emission or range extender package in urban on interurban work
Cummins has unveiled an electric powertrain that can be configured as either a zero-emission package or to utilise a small diesel range extender.
It is suitable for use in urban and interurban applications and it utilises individual battery units, each with 70kW/h of energy storage.
Up to eight can be integrated within the fully electric driveline and distributed around the vehicle, giving a maximum range of 360km on one charge.
With three battery packs in the range extender configuration, up to 85 miles of engine-off operation is possible, says Director Customer Engineering Bill Pearce. He adds that, as there is no additional space claim over a standard diesel, retrofit is an option.
The range extender utilises the 2.8-litre, 160bhp ISF engine. Cummins’ control system monitors the batteries’ state of charge and engages the engine when necessary, and it can also utilise a ‘load following’ strategy at times of high power demand.
In the latter situation, the engine will run at full output to channel maximum electrical energy to the motor-generator. Cummins says that its larger ISB units are compatible with the range extender electric driveline and that geofencing is possible.
Various charging options for both options will be available, including overnight and opportunity replenishment, and Cummins is already talking to vehicle manufacturers about the driveline in both of its forms.
The first demonstration buses are likely to debut in 2018 and production should commence in 2019.
In the range extender variant, Mr Pearce says that there is potential to pre-heat the exhaust so that when the engine restarts after a potentially long period of inactivity, there will be no short-term emissions spike before operating temperature is reached.
Both systems incorporate the same traction motor and power electronics to deliver a continuous torque output of 1,850Nm. They can provide a peak torque of 3,400Nm at times of high demand.
