NEWS

Researchers at TU Graz improve small electric motors

Thanks to innovations in design, control and production technology, brushless drives for pumps and ventilation systems work more efficiently and quietly. Users of electrical appliances and the automotive industry can benefit from this.

Image Source: Lunghammer - TU Graz

Small electric motors can be found in many household appliances, tools and computers as well as in modern cars, where they drive auxiliary units such as pumps and fans. Individually, each of these motors does not consume much energy, but together they offer great potential for savings. The research team of the recently successfully completed “CD Laboratory for Brushless Drives for Pump and Fan Applications”, led by Annette Mütze from the Institute of Electric Drives and Power Electronic Systems at Graz University of Technology, has now further exploited this potential: Through innovative design, modified control technology and the use of new manufacturing techniques, the brushless integrated drives developed here consume less power, operate more quietly and are lighter.

Angled claws reduce vibrations

Larger claw-pole motors are used in vehicle lighting systems, for example. Their use as small drives is less well known. Annette Mütze's team has reduced the so-called “cogging torques” of these small drives by beveling and grooving the claws, which does not incur any additional costs. This reduces the momentary engagement of the claws when the motor is turned and thus unwanted vibrations. “This has enabled us to reduce an important source of noise by 70 percent. As a result, the drives run much more smoothly and quietly,” says Annette Mütze.

Simplified control reduces switching losses

Efficiency gains are achieved through simplified control of the current flow. Usually, pulse width modulation regulates the current with which the motor of a fan or pump is supplied. In order for the current to flow in the desired rectangular pattern, a large number of switching operations are required, which causes additional energy consumption. “We only switch our drives on and off once per desired rectangle,” says Annette Mütze. “This has enabled us to reduce the additional energy consumption caused by switching losses enormously.” Particularly at low currents, these drives therefore have a much better overall efficiency than those that are controlled via conventional pulse width modulation. Due to the drastically reduced number of circuits, the circuit boards of the motors also require half as many capacitors, which reduces costs.

3D printing of ferrite-based material

The third innovation is the realization of PCB motors with ferrite cores. “PCB” stands for ‘Printed Circuit Board’ and, in the case of the motors, means that the windings that generate the magnetic field required for the drive are designed in the form of printed circuit boards. This allows a high degree of automation in production. Annette Mütze's team equipped the PCBs with 3D-printed ferrite cores, thereby improving the guidance of the magnetic flux in the motors. This was the prerequisite for the use of more cost-effective magnets, which are also based on ferrite.

As a corporate partner, MSG Mechatronic Systems GmbH was involved in the “CD Laboratory for Brushless Drives for Pump and Fan Applications”.

This research is anchored in the Field of Expertise “Mobility & Production”, one of five strategic focus areas at TU Graz.

Contact:
Annette MÜTZE
Univ.-Prof. Dr.-Ing.
TU Graz | Institut für Elektrische Antriebe und Leistungselektronische Systeme
Tel.: +43 316 873 7240
muetzenoSpam@tugraz.at

Multiple break-ins at the EALS Institute

Dear EALS Community,

We have some bad news: Our beloved EALS Institute has been robbed several times in the last few weeks, and important equipment for research and teaching has been stolen. We need your help to recover this equipment!

Stolen devices:

1.Power meter - Portable Data Recorder from HBK

eDrive-GEN3i-2 (serial number: IFF1400252)
GN610-2 (serial number: IFC1500476)
1-GN310B (GEN3i Upgrade) (serial numbers: IPA2100409, IPA2100408)

2. Multimeter Model 2000 from Keithley

Serial number: 758451
including Scanner Card 2000 scan

3. Multimeter Model 2700 from Keithley

Serial number: 833146
including 20 channel scanner card with cold junction 7706 (serial number: A304337)
including 40 channel scanner card with cold junction 7708 (serial number: A612717)

4. LECROY 4-CHANNEL ANALOG HDO6104-MS OSCILLOSCOPE

Serial number: LCRY3562N16439

5. LECROY HVD3605A Differential Amplifier

Label number: 195137

6. LECROY HVD3106 differential probe

Label number: 195193,195194

7. HVFO103 Optical power meter

8.LECROY HVO103 fiber optic isolated + input divider

Serial number: D011,C029

9.LECROY Oscilloscope Waverunner HRO 66ZI

Serial number: LCRY3105N58729

10. Differential probe ADP305

Serial number: C540

11. Differential probe ADP305

Serial number: C546

12. Current clamp CP031

Serial number: 214-0254

13. Current clamp CP150

Serial number: 2015-0536

14. Current clamp 30A / 100MH

15.Differential probe AP033

Serial number: 14473

16.Fluke Handheld Multimeter 28

17.Fluke handheld multimeter 87

These devices are indispensable for our research and teaching. Their loss means considerable restrictions for our projects and work.

How you can help us:

Share this post: The more people know about it, the better.
Be vigilant: Look out for these devices or the serial numbers mentioned and report any suspicious observations to us. Let us know if you are offered one of these devices or if you find it on the relevant sales markets.
Give us tips: Every tip can help us.

Contact us:

We also ask you to share our LinkedIn post if possible so that we can reach more people.

We thank you for your support and hope that with your help we will get these devices back soon.

Your EALS Institute, TU Graz

Annette Mütze in the podcast: An engineer between research and application

We are delighted to share some fascinating news: Our brilliant colleague Annette Mütze was recently a guest on the latest episode of the popular podcast “Talk Science to Me”. In the gripping episode, Annette reveals exciting details about her impressive career.

In just 19 captivating minutes, Annette gives a deep insight into her unique ability to balance basic and applied research. She talks about the challenges she encounters and the innovative solutions she develops to succeed in both worlds.

This podcast is a must-listen for anyone who is passionate about science and technology. Experience how Annette Mütze uses her passion and knowledge to push boundaries and break new ground.

Listen in and let yourself be carried away by Annette's inspiring story!

You can find the full podcast here: Talk Science to Me #33: Annette Mütze

!!! Important information for all electrical engineering students !!!

We are excited to announce that starting from the next academic year (WS2023/2024), students of "Mikroelektronik und Schaltungstechnik" will have the opportunity to take "VO 431.121 Power Electronics 2" as an elective course in the module "Electronic Systems".

And here's the best part: Credits earned from this course can be transferred once the curriculum is changed!

Don't miss out on this opportunity and enrol for "Power Electronics 2" this semester already (it's not too late) and broaden your knowledge in the field of power electronics.

Stay tuned for more updates!

09. March 2023