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Mr. John Smith

Job title



The new and further development of vehicle brake systems today mainly takes place on flywheel brake test rigs. In these test benches, the brake disc is accelerated to the desired test speed by means of an electric motor. The vehicle mass is simulated using rotating flywheel masses that are integrated in the drive train of the test rig and are thus mechanically coupled to the brake disc to be tested. Different vehicle masses are usually implemented with several inertia masses, which can be coupled and decoupled as required. An exact setting to the vehicle mass to be simulated can then be made via the drive motor, which acts as a generator/motor during the test run and thus can represent an additional positive or negative inertia. In principle, a very simple and realistic simulation of the vehicle masses can be achieved using the flywheels, but the structurally complex implementation of such a solution ultimately means a not inconsiderable cost item in the total price of such a test system. The great advances that have been made in recent years with high-torque motors and their control accuracy make it possible today to ask whether the standard centrifugal masses can be replaced by a mass inertia simulation of large motors. For this purpose, extensive investigations and calculations are currently being carried out at RENK Test System GmbH using the example of a full-scale flywheel brake test bench for brake systems in rail traffic. The results of this work will be presented with the proposed technical paper: Estimation of the limits and control accuracy of the electrical inertia simulation by testing it on the real test bench Examination of the essential assemblies (base frame, basic flywheel, floating bearing (test specimen holder), test station) with regard to the necessary function, design and costs Presentation of the advantages and disadvantages of the "classic flywheel brake test bench" compared to the "brake test bench with electrical mass simulation" We would expressly welcome a following discussion of the presented study results (also regarding the partly personal preferences of the operators).

RENK Test System GmbH: Mr Johannes Leopold, Mr Matthias Huttner, Mr. Jens Härlen, Mr. Michael Steglich

Brake dyno with minimized flywheel mass - What can modern AC motors achieve?

EB2022-CSB-001 • Oral • EuroBrake 2022 • Testing requirements and friction couples


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