A company in California, USA, spent more than two years developing and testing a motor. It claims that this motor is making achievements "never seen in the motor/generator industry". 360 Power Group, based in Marina Del Rey, said that its machines - which can also be used as generators - can achieve 98.4% electrical efficiency at 1800 rpm.
The motor uses three magnets in the rotor to generate radial axial radial magnetic fields in three precisely controlled air gaps, instead of two. Instead of using traditional field coils, it uses modular coils, which require one third less copper than usual, and reduce the size and weight of the motor in a similar proportion.
The three field design operates effectively without saturation or loss of flux. It is said to produce high power density, efficiency and torque levels at low speeds.
The rated output power of the motor can be extended from 1kW to 500kW, and full torque can be generated in the whole working range. This design allows the electronic transmission with stepless speed change to switch the three phases of multiple coils in flight. It eliminates the need for mechanical transmission, thereby saving space, weight and cost.
Low speed (less than 2500 rpm) operation reduces vibration, noise, heat, and maintenance costs compared to high speed motors.
The windings of the motor are separated into multiple detachable coil/ferromagnetic core modules instead of traditional field windings. In unlikely cases, if a coil fails, the motor will operate at a slightly reduced efficiency until the module can be replaced.
The modular coil design is said to help improve the thermal efficiency. Whether the motor is passive air cooling or active liquid cooling, it will help extend the life of the machine. Modular design also reduces manufacturing and maintenance costs. 360 Power Group said that if it is used to provide power for electric vehicles and batteries of the same capacity are used, the motor will improve the endurance by 33%. It can operate in conventional driveline configurations or hubs.
The company said that if used as a generator, fuel consumption could be reduced by one third.
The 15kW version of the 360 Power Group's electric generator (left) is on the test bench, with a conventional motor of similar rating (right).
Michael Salerno, chief design engineer of 360 Power Group, said, "This represents a fundamental innovation in motor technology. This technology can operate as both a motor and a generator, which makes possible the cooperative power engineering that has never been possible."
He added that, as a generator, "due to its power density, small size and weight compared with traditional technology, its application has become very large. Roof mounted wind turbines are now feasible. Even megawatt level large generators will become smaller, no transmission, and easier to maintain. The application of this breakthrough technology is unlimited."
The characteristics of the motor will also make aviation applications feasible, because the power weight ratio is much higher than that of traditional motors.
360 Power Group has more than 100 U.S. and international patents protecting its technology - at least 40 more are pending - indicating that it is in licensing discussions with several potential manufacturers.
360 Power Group is the operating division of Clearwater Holdings, headquartered in Nevada.
