Launch of the IEM AcousticLab


In November, the new acoustic test bench (IEM AcousticLab) was successfully put into operation at the IEM. The new testbench expands the testing possibilities at the IEM for the acoustic characterization of electric drives. In the planned expansion stage, machines with a continuous power of up to 250 kW can be measured at a maximum speed of up to 20,000 min-1.

  Test setup for initial operation in the IEM AcousticLab Copyright: © IEM Test setup for initial operation in the IEM AcousticLab.

The acoustic behavior of electrical machines is an important design and quality criterion for many applications. The modeling of the operational vibration behavior of electric drives results in considerable uncertainties according to the state of the art. In particular, the reproduction of the real vibration behavior under different operating conditions is a challenge. A metrological investigation of electrical machines under controlled boundary conditions is therefore unavoidable.

Since the power density and thus the speed are constantly increasing, especially for traction machines for mobile applications, the requirements for testing possibilities are also increasing. A new high-speed load machine with a maximum speed of 20,000 min -1 , a continuous power of 250 kW and a maximum torque of up to 700 Nm was therefore bought.

For the acoustic characterization, a sound-insulated acoustic chamber was set up. This chamber provides controlled boundary conditions for airborne sound and sound power measurements according to ISO 9614. The acoustic absorbers used provide more than 90% absorption above 450 Hz.

To decouple the noise of the load machine, it is placed outside the chamber. A spindle bearing system was designed and built for mechanical power transfer into the chamber and for dynamic decoupling.

Capacities were expanded for measurement characterization. A sound intensity probe was bought for sound power measurement. For airborne sound measurement, various measuring microphones were bought. For structure-borne sound analysis, the existing measurement capacities were expanded by interference-insensitive 1D and 3D acceleration sensors.

The test bench is currently under construction and in partial operating condition. With the new IEM AcousticLab, the institute is consistently expanding its testing capabilities for the analysis of electrical machines of the future.