Oxford-based electric motor manufacturer YASA has achieved a power density of 59kW/kg with its latest axial flux prototype motor, marking a significant increase over earlier testing results.
The company’s 12.7kg prototype motor reached a short-term peak output of 750kW during recent testing at its Oxford Innovation Centre. This represents a 40 per cent improvement on results from summer testing, when a 13.1kg version of the motor achieved 550kW, equating to 42kW/kg.
“To achieve a 750kW short-term peak rating and a density of 59kW/kg is a major validation of our next-generation axial flux technology,” said Tim Woolmer, founder and chief technology officer at YASA. “It’s proof of what focused engineering innovation can achieve. And this isn’t a concept on a screen – it’s running, right now, on the dynos.”
YASA estimates the motor’s continuous power output will be between 350kW and 400kW. The prototype is currently undergoing extended testing cycles as part of a development programme.
The motor uses no exotic materials and achieves its performance through precision engineering, thermal management and packaging optimisation. The company said the design is both compact and scalable, with the technology developed for potential use in high-performance automotive applications.
Simon Odling, YASA’s chief of new technology, said the motor’s performance had exceeded simulation predictions. “The early results are extremely encouraging,” he said. “This is real hardware, in real life, delivering real data – and it’s performing beautifully.”
The development received support from the Advanced Propulsion Centre UK. YASA said its axial flux technology delivers three times the performance density of current radial flux motors.
“Our technology is delivering measurable results today, while paving the way for a new generation of lightweight, efficient electric propulsion systems,” said Joerg Miska, chief executive at YASA.
The company has not provided independent verification of its power density claims. YASA designs and produces axial flux motors and said it would share further details about the prototype motor’s development in future announcements.
YASA specialises in axial flux motor technology, which differs from the radial flux motors commonly used in electric vehicles. The company develops motors for various applications including automotive and industrial use.
