DL EM-TEST – Automatic Test Bench for Electric Machines

The DL EM-TEST is an electric machines test bench from De Lorenzo for studying and characterising motors and generators with an automated test approach. It works with the 0.3 kW and 1.1 kW machine ranges, so one bench can be used with either. The bench has three sections: a prime mover, instruments and data acquisition software.

A three-phase squirrel cage asynchronous machine, controlled by an inverter in four-quadrant operation, supplies the mechanical power and torque needed to test the machine under study. Instruments record speed, torque and temperature, together with AC and DC voltage, current and power. LabVIEW-based software reads these values over a serial port using the Modbus protocol and guides students through each experiment from an on-screen interface. Students can monitor and control several variables in real time and see how they interact under load, no load, variable speed and torque, or different excitation values.

The automated characterisation of motors and generators covers motor and generator operation, torque against speed and current, voltage against speed, efficiency, generator synchronisation with the network and power factor, depending on the machine under test. The characteristic curves give the data needed to model a machine and tune its controller. Configurations are available for three-phase asynchronous motors, single-phase motors, DC motors, DC generators and three-phase synchronous machines, each in both power ranges. Bestech Australia supplies the DL EM-TEST with on-site training and commissioning support available.