| Type of the defence: |
Ph.D. |
| Name: |
Petr Kujan |
| Name of the thesis: |
Optimální PWM problém |
| Abstract: | The thesis deals with optimal pulse width modulation (PWM) problem which
is an
established method of generating PWM waveforms (or general multilevel
waveforms) with
low baseband distortion. We focused on optimal computation of switching
times of a PWM
waveform for generating general odd symmetric signals with applications
in control. We
introduce an exact and fast algorithm with the complexity of only O(n
log^2 n) operations.
This algorithm is based on converting appropriate trigonometric
equations of each harmonics
to a polynomial system of equations that is in turn transferred into a
special system of power
sums. The solution of this system is carried out by a modification of
Newton’s identity, Pade
approximation theory, formal orthogonal polynomials theory and
properties of symmetric
polynomials. Finally, the optimal switching sequence is obtained by
computing the zeros of
two formal orthogonal univariate polynomials.
Application cover control of large electric drives, power electronics
converters, active
harmonic filters, optimal (micro) electro-mechanical systems or digital
audio amplifier.
Implementation of fast and efficient proposed algorithms on dedicated
hardware, e.g. digital
signal processor, opens a possibility of better on-the-fly construction
and more accurate and
faster solutions. It can result in increasing full or power efficiency,
lower emissions, and
better performance.
|
| Supervisor: | Prof. Ing. Michael Šebek, DrSc. |
| Date and time of the defence: |
9:00, 23.10. 2009 |
| Venue: |
ČVUT FEL v Praze, Katedra řídicí techniky, Karlovo nám. 13, 121 35 Praha 2, budova E v areálu Strojní fakulty, místnost 14 |
| Date of record: |
21.9. 2009 |
| Statute: |
nezadáno
|
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Last modification:
01.10.2008
