Vector modulation
By means of vector modulation, an extended range of information can be transmitted on an existing carrier of limited bandwidth compared to conventional modulation methods . The term vector modulation is also used in drive technology. Here, however, it is not a question of the transmission of information, but rather a modulation of the space vector within the framework of vector control in order to achieve the most ideal properties possible in electric motors.
Vector modulation in telecommunications
Known analog modulation methods from conventional color television technology are based on vector modulation. These include PAL and NTSC . Here the color information is modulated as a difference to the brightness signal, or later recovered. The vectorscope is a specialized measuring device for displaying the color information in analog image modulation processes .
Because of the economic use of the limited bandwidth resource in the radio sector, vector modulation forms the basis of many digital modulation methods which, in addition to digital television, are increasingly used in other data and communications technology. The best-known digital vector modulations are quadrature phase shift keying (QPSK), amplitude phase shift keying (APSK), quadrature amplitude modulation (QAM), discrete multitone (DMT) or orthogonal frequency division multiplex (OFDM) (both multiplex on several carriers). Measuring devices for analyzing the digital modulation methods are called vector analyzers .
Vector modulation in drive technology
→ Main article: Space vector modulation
In drive technology, induction machines are partially controlled using vector control . Since the output variable of the control algorithm is available as a space vector , it makes sense to control the induction machine using space vector modulation.
In addition, other proprietary names exist at various companies. For example, vector modulation was researched at Siemens under the name transvector control from around 1970. The active marketing by Siemens found inter alia in the air gap control of Transrapid - linear motor instead.
Individual evidence
- ↑ Regulated three-phase drives (accessed on October 2, 201)
- ↑ Christoph Meinel, Harald Sack: Internetworking. Technical basics and applications. Springer-Verlag, Berlin / Heidelberg 2012, ISBN 978-3-540-92940-6 , pp. 96-105.
- ^ Walter Fischer: Digital television technology in theory and practice. Springer Verlag, Berlin / Heidelberg 2006, ISBN 978-3-540-29203-6 , pp. 303-312.
- ^ Ekkehard Bolte: Electrical machines. Springer Verlag, Berlin / Heidelberg 2012, ISBN 978-3-642-05484-6 , pp. 100-102.
- ^ Claus Wehrmann: Electronic drive technology. Dimensioning of drives with Mathcad, Friedrich Vieweg & Sohn Verlag, Wiesbaden 1995, ISBN 978-3-663-09916-1 , pp. 77-84.
- ↑ Strong drive for 150 years (accessed on October 2, 201)