Ground-breaking gearbox designs for an energy-efficient future

Xtrac continues to lead the way in innovative transmission design for future road cars, recently winning the Queen’s Award for Enterprise for development of its Integrated Lightweight Electric Vehicle (ILEV) gearbox range.

Since the inception of low carbon vehicle technologies, Xtrac has designed and manufactured revolutionary high performance transmissions for use in a wide range of low carbon powertrain configurations, working in collaboration with many of the industry’s top organisations, including Williams Advanced Engineering, Jaguar Land Rover, Lotus and Nissan.

Xtrac’s family of ILEV transmission systems was initiated from the company’s considerable experience of designing high performance hybrid and electric road vehicle transmissions from as far back as 2008, and now includes three different configurations to suit a range of applications.

Starting in 2016 with a growing market requirement for single speed, lightweight and power dense electric vehicle (EV) transmissions, Xtrac revealed the new P1227 paired with two YASA P400C motors per input to the transmission. Drawing on Xtrac’s precision design and manufacturing engineering capabilities, specific focus was put on ensuring the ground helical gear sets adopted for this transmission were silent for the most demanding electric vehicle applications. Together with the P1227’s torque vectoring capability and rating to a total peak input torque of 1,560Nm and 640kW (870PS) the P1227 quickly became a popular choice for many high performance EV applications.

The P1289 is a descendant of the innovative P1227 transmission and features a single speed 3-shaft configuration with an integrated park-brake and a high performance motorsport limited slip differential. Aston Martin selected this transmission for their first all-electric car – the Rapide E – which required a lightweight, extremely efficient and package optimised solution. As a result of working closely with the vehicle design team and Integral Powertrain, the motor supplier, this highly integrated transmission utilises two rear mounted electric motors producing a combined target output of just over 610PS (450kW) and a colossal 950Nm of torque, providing the balance of power and refinement required for such a vehicle.

The latest addition to Xtrac’s energy-efficient ILEV family is the P1320 – a single-speed epicyclic transmission with an integrated high performance electric motor, capable of a maximum speed of 17,000rpm with a peak input torque of 425Nm. Coupled with a mass of just 12.5kg, this high-power density solution has been chosen by Lotus for their revolutionary new hyper EV, the Evija, which required a tightly packaged EDU (consisting of transmission, motor and inverter) to power each wheel, resulting in a total vehicle power output of 2,000PS (1,470kW), making it the world’s most powerful series production road car.

Xtrac continues to develop the ILEV family to satisfy the silent running, innovative packaging, power density and efficiency demanded by the high performance EV sector of the market.

Xtrac’s P1320 is the latest addition to its family of Integrated Lightweight Electric Vehicle (ILEV) transmission systems