4.3‘‘ colour TFT display: 1800 series
Modern digital technology and safety current limitation for unproblematic workspace designs.
Test system for inverters and 3-phase asynchronous motors of mild hybrids under environmental conditions.
Industry: Automotive industry / electric motors
Electric motors of mild hybrid vehicles shall be tested under conditions as close to reality as possible. Besides different static and dynamic function tests, the 3-phase asynchronous motor, as well as the inverter, shall be cooled down to -20 °C and heated up to +70 °C afterwards. Thus, the demands on motors that can occur during operation of an electric / hybrid vehicle are simulated.
The test system is to be used in the analysis for persistent tests which are not possible in production due to short cycle times.
To be able to test the motor, inverter and the end product (motor + inverter) separately, three single test stations were developed and combined in one compact system.
The inserted motor is operated by a 48 V inverter at different load-points and tested. The carried out tests include voltage measurement, current measurement up to max. 500 A, COS-Phi calculation (ratio between reactive power Q and apparent power S), performance calculation and the locked-rotor test. During this test, the rotor is blocked with the help of a servo motor and a low voltage is applied to determine the short-circuit current of the motor.
The inverter is connected to a motor simulation as well as to the cooling cycle of the system for the first time. Besides a voltage and current measurement up to max. 400 A, the performance and the correct communication of the CAN interface are tested.
Complete system station
The DUT (inverter + motor) is connected to the 48 V supply and the cooling cycle. A load machine is connected to a pulley wheel and the complete test proceeds fully automatically. During testing and in addition to the load tests, an environment simulation is carried out where the DUT is cooled down to -20 °C and heated up to +70 °C afterwards. Thus, the DUT is tested under conditions as close to reality as possible. An automatic discharge per software at the end of the test guarantees the personnel’s security.