High speed test bench

• Subject Area: Electrical Engineering and Information Technology
• Term: Funded in 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 517384694

For decades, three-phase electric motors for driving rotating machines were limited to speeds of 3,000 rpm and below due to the lack of power electronics, which resulted in point-optimized units. It was only with the availability of reliable, low-cost power electronics in the 1990s that it became possible to drive the electric machine at other speeds without having to use a gearbox, which is disadvantageous in many respects, or wear-prone DC motors. With frequency converters, three-phase motors can now reach speeds beyond 3,000 rpm. Depending on the application, this can be several 10,000 1/min for tool spindles, and even more than 100,000 1/min for electric dental drills or electric turbochargers. Such high speeds have various advantages, such as the significant improvement in the use of resources (size reduction through higher speeds with the same power) or the improvement in efficiency, dynamics, service life and costs through the elimination of the gearbox. However, a high speed can also be necessary or advantageous due to the process, for example in turbo compressors (fuel cell chargers or exhaust gas turbochargers), turbomolecular vacuum pumps, high-speed turning and milling applications, motor-generators for flywheel accumulators, generators for micro gas turbines or centrifuge drives. The applicant's working group is already researching electric motors made of special materials that have lower losses compared to conventionally realized electric motors, especially at high speeds and frequencies. The co-applicants are researching: (i) high-speed frequency converters, which are excellent for driving high-speed electric motors; (ii) CFRP (Carbon Fibre Reinforced Plastic) bandages for absorbing centrifugal forces on rotors in high-speed applications; (iii) CFRP components such as shafts, which are to be subjected to a high-speed test followed by ultrasonic detection for mechanical testing. The working groups of the applicant and co-applicants cooperate closely in the research focus "Highly efficient technical systems". The research work on high-speed applications is currently limited by the lack of a high-speed test bench to test and optimise the solutions developed under realistic conditions and to acquire new projects. A suitable large-scale device is therefore to be procured. It consists of the main components machine frame, active load machine in 4-quadrant operation, high-performance gearbox and high-precision measuring devices (such as torque sensor, vibration meter, current transformer). The large-scale device significantly expands the performance spectrum of the research focus "Highly Efficient Technical Systems" and can be used by all affiliated working groups and in-institutes.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Hochdrehzahlprüfstand
• Instrumentation Group: 2560 Prüfstände für Fahrzeuge und Aggregate (außer Motorenprüfstände 286)
• Applicant Institution: Hochschule Kaiserslautern
• Leader: Professor Dr.-Ing. Sven Urschel