Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Solving the problems of electric motors run from power converters

09.12.2003


In this PhD thesis, Eugenio Gubía proposed a solution for the problems of electric motors run from power converters. Controlling motors and electric generators by means of power converters has negative effects with the presence of overtvoltages and high-frequency currents throughout the installation. These effects accelerate the ageing process of the motors and, moreover, can provoke faults in the correct operating of the control circuits.



Thus, in his PhD, Mr Gubia has developed a generic method that can be adapted to each one of the possible installations with the view to identifying the origin of the high-frequency problems and, moreover, to analyse possible solutions. Likewise, the proposed method can be adapted to the design stage of a new installation.
In order to design this method, it was necessary to set up simulation models to reproduce the behaviour of motors, transformers, cables and the power converter, using frequencies in the order of 10 megaHertz. These frequencies are much higher then the tens of kiloHertz used in classical models.

Concretely, in this work it has been possible to reproduce the overvoltages produced as a result of using long connection cables between the inverter and the motor given that, the longer the cable, the greater the probability of overvoltage. This type of cable can be found, for example, in wind-powered generators, which incorporate the generator (the motor) in the upper part of the structure and the power converter at the base.



Also in this thesis, the problem of earthing currents in the installation and the supply grid was investigated, a problem known as electromagnetic interferences or conducted EMI. These have become highly important of late as they can provoke a fault in other units connected to the same earthing system. In fact, the regulations which limit the amount of such currents are increasingly stricter.

Eugenio Gubía has put forward that solutions to both problems, overvoltages and interferences, require the use of filters, the study of which, in this work, has been approached from a perspective of wave theory in transmission lines.
If the electromagnetic interferences do not have a technique or device for their quantification at the heart of the operation, neither can the efficacy of the filters applied to eliminate said effects be measured.

To this end, the work developed in this PhD offers a precise methodology for the analysis of both overvoltages and electromagnetic interferences and that, moreover, enables an efficient filter design.

The author of the thesis is currently researching the possibility of applying this methodology to other fields of power electronics.


Contact :
Iñaki Casado Redin
Nafarroako Unibertsitate Publikoa
inaki.casado@unavarra.es
(+34) 948 16 97 82

Garazi Andonegi | Basque research
Further information:
http://www.basqueresearch.com/berria_irakurri.asp?Gelaxka=1_1&Berri_Kod=370&hizk=I
http://www.unavarra.es

More articles from Power and Electrical Engineering:

nachricht Did you know that the wrapping of Easter eggs benefits from specialty light sources?
13.04.2017 | Heraeus Noblelight GmbH

nachricht To e-, or not to e-, the question for the exotic 'Si-III' phase of silicon
05.04.2017 | Carnegie Institution for Science

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>