Yamaha’s MOTIV.e city car concept equipped with Zytek electric powertrain
Yamaha’s new MOTIV.e city car concept, shown at the Tokyo motorshow, is powered by an electric drive from Zytek that employs a range of new design approaches to minimize the cost, weight and size of the powertrain while maximizing the performance and range. By supplying a number of core high voltage components as an optimized system, Zytek is also minimizing the time required for vehicle development.
MOTIV.e comes from the partnership between Yamaha and Gordon Murray Design, using Murray’s iStream® manufacturing technology to deliver an electric vehicle at an affordable price. Zytek’s sales and marketing director, Steve Tremble says that taking a fresh approach to the powertrain is central to achieving these goals.
“Yamaha wanted the vehicle to reflect the company’s reputation for outstanding engines,” he adds. “Interpreting this in an electric vehicle has driven excellence in performance and driveability, as well as in weight reduction and efficiency, building on the potential of iStream to deliver an agile drivers’ car as well as maximizing the range.”
Zytek supplies the electric motor, paired with a single speed reduction gearbox from Vocis, and the electronic vehicle control module (EVCM) which provides the interface between the powertrain and the rest of the vehicle. The low cost power electronics is manufactured in high volumes by Zytek’s technical partner Continental. To help achieve the light weight and high efficiency targets for the MOTIV.e, the 25 kW motor revs to 15,000 rpm, much higher than comparable units. This substantial increase in motor speed allows the electric engine to be smaller, lighter and more cost-effective than previous-generation units.
“The motor weighs 13 kg, the gearbox 11 kg,” explains Zytek’s engineering program manager, Neil Cheeseman. “These are components that you can pick up with one hand.”
Cheeseman believes the power electronics also set new standards for weight and packaging. The inverter, for example, weighs 7.5 kg. “By making everything in house, Continental has eliminated many of the compromises that stem from using bought-in components,” he said. “Their substantial investment in power electronics has delivered a scalable, power-dense and cost-effective product range that is already proven on everything from small city cars to hybrid commercial vehicles.”
The Zytek EVCM is being built on an electronics platform that duals as a development tool and a cost-effective production unit complying with all relevant automotive standards. Zytek says that unlike other dual-purpose systems that are suitable for production, their unit is cost-competitive with bespoke production technologies. It is also thought to be the only EVCM that takes a further step in powertrain control integration by including thermal management within the decision-making algorithms.
“This is a new generation of EVCM that integrates torque arbitration, temperature control and voltage management to allow better decision making,” Cheeseman explains. “It optimizes the driver’s torque request based on a broad range of parameters including battery charge and temperature and the grip available at the tires. By integrating these decisions, we can provide more with less to improve both the driving experience and the range while reducing the size, weight and cost of the power electronics and battery pack.”
Yamaha MOTIV.e technical specification
This vehicle type could be used by urban rental companies like AutoLib in Paris. Do you think Yamaha’s vehicle will be in the Request For Quotation short lists of rental companies? Or will this vehicle be sold to final customer directly?