| Abstract |
The development and the utilisation of a modular inverter for control of an induction or synchronous motor in a power electronics and electrical drives laboratory allows students to gain deep understanding. For easy deployment of own code and verification of analytical calculations a hardware-in-the-loop controller is used.A modular laboratory hardware presented in previous work allows students to explore a variety of DC/DC-converter topologies. The most complex setup possible was an H-bridge designed for components with 200 V breakdown voltage at most. In order to extend this teaching concept to three-phase drives, a topology consisting of three inverter legs including an auxiliary voltage supply was developed extending the maximal component voltage to 600 V while retaining the modular structure. While a Arduino Nano was sufficient for the control of DC/DC-converters, its performance is by far insufficient for e.g. space vector modulation as used in field-oriented control. Since the PLECS simulation software from Plexim GmbH is used in the power electronics and drive technology lectures, it was straightforward to use it in combination with hardware-in-the-loop (HIL) control. Plexim offers the RTBox CE as an inexpensive entry-level HIL-System. In the context of this publication, a RTBox CE is connected directly to the modular inverter driving a three-phase motor via an interface board. In order to apply a variable load the three-phase motor is connected in a motor test bench to a DC motor via a speed/torque measuring shaft. Actual values of rotor speed and rotor angle are essential for field orientated control of the motor. Therefore the evaluation of the measuring shaft data is also performed by the RTBox.The set-up, its possibilities and limitations are presented as examples within the scope of this work. |
