Compact Dynamics, a German electronics firm associated with MAHEPA, the green aviation consortium, has developed two types of electric motor-controller combinations adaptable to aeronautical use. Their Dynax® Transversal flow machines and Dynadyn® Radial flux drives integrate power electronics with the motor.
Their Dynax MGi25-48, one of two lower-power motor-controller combination, is rated at 25 kilowatts (33.5 horsepower) maximum power at 58 Volts, and 20 kW continuous output. The small motor can generate an impressive 75 Newton-meters (58.3 foot pounds) of torque from its 14 kilogram (30.8 pound) heft. Even with its controller mounted atop, the full motor package is only 318 millimeters (12.5 inches) high, and 233 mm (9.17 inches) deep. The motor itself is only 107 mm (4.2 inches) thick. Its 10,000 rpm top speed obviously requires a propeller speed reduction unit for best efficiency.
A higher-voltage model, the MG40-400, apparently under development, will operate on 300 to 415 Volts, and put out 40 kW (53.6 hp.) from 350 Volts. The motor weights 10.2 kg (22.44 pounds), but the controller adds 5.6 kg (12.32 pounds).
Compact Dynamics’ Dynadyn radial-flux motors are more powerful, and a bit thicker than their lower-power cousins, but still compact and light weight, each weighing 13 kilogram (28.6 pounds) with integrated controllers. The Dynadyn 75 has a maximum 75 kW (100.5 hp.) and 25 kW (33.5 hp.) continuous output: the Dynadyn 85 achieves 86 kW maximum and 55 kW (73.7 hp.) continuous power. They generate 69 and 79 nM (50.9 ft-lbs. and 58.3 ft.-lbs.) of torque, respectively. They weight 5.8 and 6.6 kg (12.76 and 14.52 pounds), respectively.
All motors are liquid cooled and are “Characterized by a very low moment of inertia and high dynamics. With the high power density and low weight there are different options for use of the Dynadyn®-drives in motorsports or aviation.” All use CAN protocol and can be adapted for various applications with a number of options. Prices will probably reflect those for those for the 500e drive system for Formula Student teams, 9,000 euros for a 42 kW (56.3 hp.) motor-controller combination.
Certainly, the motors have characteristics that can be adapted to aircraft use, and the company claims that it will produce configurations that suit client’s individual requirements. These are similar to the Qinetix motor outlined here a few weeks ago. It’s nice seeing competitive forces rising in the electric aerospace market.