Ultra-efficient motors for tomorrow’s electromobility
Test operation and test acceptance of the DeepDrive double rotor with power supplies from EA Elektro-Automatik
As a development partner, EA Elektro-Automatik (EA) puts this claim into practice every day. This is particularly evident in its collaboration with the Munich-based high-tech company DeepDrive, founded in 2021. EA supplies test systems for the development and test acceptance of the DeepDrive double rotor radial flux machine. The patented double rotor technology has the potential to change the game in the automotive industry, increasing the range of electric vehicles by up to 20% and reducing manufacturing costs by up to 30% per Nm. This puts DeepDrive and EA on the forefront of next generation of electric vehicles.
“EA’s power electronics have advanced the technical development of our motors”, confirms Maximilian Habersbrunner, Co-Founder and Testing Infrastructure Lead at DeepDrive. “We use bidirectional power supplies for all test acceptances of our products and benefit from particularly high performance in a small space.” In test operation, the systems with devices from the EA-10000 series supply the inverter in DeepDrive’s transaction drives. The devices are controlled via the higher-level engine test bench control. Communication takes place via CAN. The power supplies work in parallel in master-auxiliary operation. “The modularity and compactness of EA’s test system provide a major advantage”, says Habersbrunner. “We expanded it from an initial 90kW to 210kW/560A and have additional capacity at any time.” Equally important to DeepDrive are the system’s small CO2 footprint achieved through high energy recovery and technical factors such as low ripple voltage.
Patented DeepDrive double rotor
The patented double rotor radial flow machine can either be integrated into the wheels construction or serve as a traditional central drive. As a wheel hub motor (in-wheel drive), the double rotor is particularly efficient as this configuration does not require gearboxes, differentials, drive shafts or a reduction gear, thereby eliminating transmission/mechanical loss. This makes drive energy fully available, which increases motor efficiency up to 97%. The DeepDrive double rotor impresses with its highest torque and power density and is equipped with a SiC MOSFET inverter as a plug & play solution. The motor topology of the central drive takes DeepDrive to the next level with the double rotor.
Three motor variants for different vehicle classes
With a voltage of 400V to 800V, DeepDrive has developed 3 motor variants: the RM 1500 with 1500 Nm, 150 kW and 32 kg for the compact class, the RM 1800 with 1800 Nm, 180 kW and 35 kg weight for medium and large electric cars and the RM 2400 with 2400 Nm and 250 kW, which weighs 37 kg and was designed for the performance models. Together with Continental, DeepDrive is working on a so-called corner unit for the wheel hub with an integrated brake, which was named “Innovation of the Year” in 2023. If the electric motor is placed in the wheel itself, there is more space for the battery and the electric cars can be built smaller and lighter.
Cost-effective mass production
The drive units are optimized for cost-effective mass production. In production, the double rotor requires 80% less iron and 50% less magnetic material. Above all, rare earths can be dispensed with, which reduces the CO2 footprint. Overall, manufacturing costs are reduced by 30% per Nm compared to conventional electric drives for vehicles.
Experienced experts, well-known investors
DeepDrive is currently working with eight of the ten largest car manufacturers on various development projects and plans to bring the dual rotor to the market in large-scale production by 2026. The company consists of over 70 experts from leading companies in the automotive industry and is supported by renowned investors such as BMW i Ventrures and Continental’s Corporate Venture Unit. In April 2024, DeepDrive was awarded the “German Innovation Award”. EA Elektro-Automatik is one of the pioneers of power electronics in areas such as e-mobility. In addition to test systems for all electronic vehicle components, the company offers an extensive product portfolio for testing battery cells, modules and packs as well as fuel cells.
