HPDM-30 integrated electric motor drive

HPDM-30 is an integrated electric motor drive from H3X for aircraft and other demanding propulsion applications. It combines a brushless electric motor and a silicon carbide inverter in one liquid-cooled housing, so the machine and its power electronics are delivered as a single unit that connects to a high-voltage DC bus and a CAN network.

The drive produces 33 kW of continuous power in a 4.1 kg package, which corresponds to a continuous specific power of 8 kW/kg. Continuous torque is 15.8 Nm and maximum speed is 20,000 rpm. Peak efficiency is 95 percent. For an integrator, the power-to-weight figure determines how much propulsion mass a platform has to carry, and the speed range sets the gearing needed between the drive and a propeller or rotor. The maximum DC bus voltage is 450 V.

The construction is built around a stator winding with high thermal conductivity and resistance to partial discharge, and an inverter built from discrete SiC devices with a self-sensing rotor position algorithm, so no separate rotor position sensor is described. A single additively manufactured cooling jacket cools the stator and the power electronics at the same time. The coolant is liquid, which means the installation needs a pump and heat exchanger in the aircraft thermal loop. The winding is designed to tolerate short-circuit currents without damage.

For integration, the unit measures 130 mm in diameter and 173 mm in length. Communication is over CAN. Control modes are torque, speed and, in generator mode, DC bus voltage. Power flow is bidirectional, so the same hardware can act as a motor or as a generator, for example in a hybrid-electric powertrain. Operating temperature is from -40 C to 60 C and the maker lists operation up to 45,000 ft in electrical terms.

H3X notes that the specifications, power and torque curves and efficiency map are approximate and based on dynamometer data and simulation, and asks customers to contact the company to determine suitability. Datasheet and CAD files are provided through the product page.

Typical applications include propulsion for eVTOL and other electric aircraft, large uncrewed aircraft, hybrid-electric generator sets, and also marine and heavy industry uses that H3X lists among its markets.