By Graduate Engineer, Doctor of Technology, Georg Ofner, and Graduate Engineer (University of Applied Sciences) Andreas Zelle, BULME Higher Technical School

All over the world, there is an ongoing transition from fossil fuels to renewable energy sources to fight global climate change. Industries and researchers are looking for new ways to fuel human societies. The Department of Electrical Engineering at the Austrian higher technical school, BULME is preparing future engineers for this challenge by establishing two new laboratories for "Electric Mobility" and "Renewable Energies"  equipped with high-end power analyzers from Dewesoft.

The buzzwords "e-mobility" and "renewable energy" are on everyone's lips at the moment, and all of us are overwhelmed with information and advertising on these topics every day. The media usually only provide nice pictures and words, but very few people know exactly what it actually means.

Not so in the Electrical Engineering Department at BULME. Here these topics are concrete, full of life and activity. The planning and investments in this direction began already five years ago. In January this year, two new laboratories for "E-mobility" and "Renewable Energies" were completed and made accessible for teaching.

BULME is a higher technical federal teaching and research institute located in Graz - Gösting and with approximately 2,600 students, it is the second-largest higher technical institute in Austria. The name BULME is an acronym and stands for Federal Institute for Mechanical and Electrical Engineering. 

The new laboratory rooms, including the furnishings, were brought up to the current state-of-the-art, redesigned from the ground up, and aligned for the future. The focus was mainly on an appropriate number of laboratory and training stands. True to the motto "learning by doing (yourself)", with up to five identical individual exercise stations per laboratory, it is now possible to divide the laboratory groups into teams of two or three.

The Electromobility Laboratory (EMLA)

The laboratory focuses on electrical machines and drives technology as well as power electronics. The existing test benches and equipment offer everything needed, engaging, and up-to-date. The test benches can be configured variably depending on the focus of the exercise. Different machines such as asynchronous, synchronous, and direct current machines as well as permanently excited synchronous and double-fed asynchronous, can be set up and measured. 

Three-phase current sources or frequency converters including control software tools are available to supply the machines. With the flexibly configurable test benches, which can be operated with speed or torque control, it is possible to simulate demanding load cycles. In the field of frequency converter technology, semiconductor modules also offer several possibilities for measuring the interaction and performance of power electronics.

What would a laboratory be without measurement technology? No savings were made in this area either: Investments were made in high-end power analyzers from Dewesoft. 

With these top devices, the time signals of the machines and frequency converters can be recorded with high precision, and voltages, currents, performance data, or torque can be determined from them. The time curves and the calculated RMS values ​​are displayed simultaneously and can be flexibly adapted to the specific needs of the different measurement tasks. In this way, the measured signal curves of voltage and current can subsequently be processed and evaluated within the software, which is freely accessible to everyone. 

With these devices, there are now many possibilities to solve measurement technology tasks at the highest level and implement them in praxis. One thing is also important to mention. The partnership between BULME and Dewesoft will continue intensively. A diploma thesis in e-motor test bench measurement technology is already being prepared together.

Dewesoft Sirius Power-Analyzer: power measurement, three-phase vector diagram, and high-resolution display of the time curves including spectrograms.
Figure 1. Dewesoft Sirius Power-Analyzer: power measurement, three-phase vector diagram, and high-resolution display of the time curves including spectrograms.

Data Acquisition (DAQ) Hardware and Software

DAQ Hardware and accessories

  • Five SIRIUS Power Analyzer modules
  • SIRIUSi-4xHV-4xLV: high-speed data acquisition with 1MHz, 4 x high-voltage inputs up to +/-1600V, and 4 x low-voltage universal inputs mainly for current clamps, but with adapters flexible for almost any kind of sensor
  • DSI-RTD adapters for temperature measurement
  • DSI-ACC adapters for vibration measurement
  • Adapters to use existing current-clamps

DAQ Software

  • DewesoftX data acquisition software
  • Dewesoft Power option
  • Live-calculating 3-phase frequency-variable electrical power systems with many parameters such as active, reactive, and effective Power, cos phi, Flicker, Harmonics, Total Harmonic Distortion, Star/Delta transformation, and more. see Power Solutions Manual for details)
  • Dewesoft Excel-Writer plugin

Frequency converter engine test bench and power measurement with the Dewesoft power analyzer.
Figure 2. Frequency converter engine test bench and power measurement with the Dewesoft power analyzer.

The 4BHET opened laboratory operations in the EMLA in the summer of 2022 and made the DC machines "dance and whirr"
Figure 3. The 4BHET opened laboratory operations in the EMLA in the summer of 2022 and made the DC machines "dance and whirr".

The Renewable Energy Laboratory (ENLA)

This laboratory focuses on renewable energies. This laboratory is also equipped with five independent laboratory spaces and offers everything that makes an electrical engineering heart beat faster. Here, the components for photovoltaic systems can be examined, set up, and measured, and different operating states and external influences, such as shading, can be simulated and validated. 

PV inverters and grid feed-in converters with battery storage modules offer the possibility of simulating real grid conditions and examining the interaction between energy production and consumption and intermediate storage in the model. This also spans the arc to the electrical engineering workshop and offers interesting cooperation and joint activities with the Green Village. 

Wind energy is also an essential pillar of renewable energy production. In this area, too, the actual operation of a wind turbine can be set up and simulated with the exercise modules in the EMLA. Effects such as gusts of wind, weak wind, and main voltage fluctuations can be manufactured and analyzed.

A view of the new laboratory for renewable energy and the test stand for photovoltaics.
Figure 4. ENLA, A view of the new laboratory for renewable energy and the test stand for photovoltaics.

The electrical engineering department at BULME meets the needs and the spirit of the times with the two new laboratories and the newly built electrical workshop. It has reacted promptly to one of the most important trends in the field of energy technology and the modality of the 21st century. In this way, BULME is fit for the future and can offer top, state-of-the-art training for the electrical engineers of tomorrow.