Motors for tomorrow: Lighter and more efficient rotors made of new high-strength, non-oriented electrical steel grades

ThyssenKrupp Steel Europe aims to make hybrid and electric vehicles lighter and more efficient. The company has developed new electrical steel grades for motors that can help significantly increase torque compared with the best standard grades. In parallel, experts from ThyssenKrupp Presta Camshaft have developed a complete rotor shaft that additionally saves weight. ThyssenKrupp Steel Europe will be displaying rotor and stator at this year’s EuroBLECH trade show from October 21 to 25 in Hanover, hall 17, booth E 33.

The future of mobility is supposed to be electric, but the requirements electric motors have to meet are enormous: They need to offer high speeds and increased torque but at the same time be energy-efficient, save weight and conserve resources. ThyssenKrupp Steel Europe has analyzed these requirements and developed new electrical steel grades for drive motors that allow higher torques through an optimized motor design. In a matching effort, engineers from ThyssenKrupp Presta Camshaft have designed a complete rotor that weighs less thanks to a new product architecture.

Weight down, torque up

In the “InCar plus” project ThyssenKrupp’s experts took a close look at the heart of hybrid and electric vehicles, the drive motor. The non-oriented electrical steel specialists at ThyssenKrupp Steel Europe in Bochum developed new high-strength and extra-high-strength electrical steel grades. Thanks to optimized design possibilities in permanent magnet-excited synchronous machines, these grades produce less magnetic leakage, making it possible to increase torque or reduce costs by using less magnet material. In addition the new developments provide magnetic guarantees for higher frequencies of, for example, 400 Hz and guaranteed mechanical properties.

Rethinking the rotor shaft

At the same time, engineers at ThyssenKrupp Presta Camshaft set about rethinking the motor rotor shaft, moving away from the usual one-piece design to a modular solution. For this, the company’s research department developed a new product architecture. The ThyssenKrupp rotor shaft is hollow, which not only reduces weight but also allows multi-functional use. The shaft is covered with tailored steel laminations from ThyssenKrupp Steel Europe. Rotor shaft and rotor laminations are optimally matched to each other. As a result the rotor weighs almost two kilos less than competitor models.

The lightweight option offered by ThyssenKrupp means that less energy is required, so battery capacity and weight can be reduced. Initial test results confirm these advantages for the hybrid and electric vehicles of tomorrow.

Visit us at EuroBLECH 2014 from October 21 to 25 in Hanover, hall 17, booth E 33.