IHI succeeds in developing a prototype of a high-power electric motor for aircraft propulsion systems
IHI, in collaboration with Akita Prefectural University (President: Junichi Kobayashi), Akita University (President: Fumio Yamamoto), and local companies in Akita Prefecture, has successfully developed a prototype of a 250-kW high-power electric motor for aircraft propulsion systems.
The electric motor is being developed as an electric hybrid propulsion system. With a power output of 250 kW, the motor has a high-power output comparable to a 3-liter turbo engine for passenger cars, and the heart of the motor, which consists of permanent magnets and an iron core, has a compact design with a volume of approximately 3 liters.
IHI envisages the motor would be increased to more than 1 MW and installed as an electric hybrid propulsion system in a 200-seat medium-sized passenger aircraft.
©Akita University
©Akita Prefectural University
This development is the result of collaboration between the Joint Research Center for Electric Architecture (Centre Director: Junichi Sakaki), jointly run by Akita Prefectural University and Akita University, under a cabinet office’s project funded by the Subsidy for Regional University & Regional Industry Creation Project for Industry Creation, IHI and local companies in Akita Prefecture. The permanent magnets are arranged based on a high-density magnet array (Halbach array*) to maximize the efficiency of magnet utilization and achieve high output (high efficiency), downsizing, and weight reduction.
In this development, IHI collaborated on the structural design of the prototype and solved the manufacturing problems of the stator (non-rotating part of the motor component). In order to achieve a compact, lightweight, high-power motor, the rotor must have a high-density magnet arrangement so that the individual magnets have a strong repulsive force, and the stator must have a high-density arrangement of high-power coils in numerous slots (grooves), each of which was considered difficult to industrialize using conventional manufacturing methods. However, IHI has now overcome these problems by developing manufacturing methods for coils and cores (iron cores).
IHI will continue to work on the development of an electric hybrid propulsion system for the electrification of aircraft, aiming for practical use in the 2030s, and will also work on the electrification and optimization of the entire aircraft system.
Halbach Array: a special arrangement of permanent magnets. In a general magnet arrangement, both sides have the same magnetic force, but the magnetic force on one side of the arrangement is increased and the magnetic force on the opposite side is reduced to almost zero, thereby maximizing the efficiency of magnet utilization.