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Space vector modulation is a PWM control algorithm for multi-phase AC generation, in which the reference signal is sampled regularly; after each sample, non-zero active switching vectors adjacent to the reference vector and one or more of the zero switching vectors are selected for the appropriate fraction of the sampling period in order to ...
The carrier-based PWM technique compares the AC output waveform, v c, to a carrier voltage signal, v Δ. When v c is greater than v Δ , S+ is on, and when v c is less than v Δ , S− is on. When the AC output is at frequency fc with its amplitude at v c , and the triangular carrier signal is at frequency f Δ with its amplitude at v Δ , the ...
Fig. 4 shows the conduction states of the system, and from this we get the input space vectors shows in Fig. 5 [12] Fig 5: Conduction states of the Vienna Rectifier, for ia>0, ib,ic<0, valid in a sector of the period T1 sa, sb, and sc characterise the switching state of the system. The arrows represent the physical direction and value of the ...
When carrier-based PWM techniques are applied to six-step waveforms, the basic overall shape, or envelope, of the waveform is retained so that the 3rd harmonic and its multiples are cancelled. 3-phase inverter switching circuit showing 6-step switching sequence and waveform of voltage between terminals A and C (2 3 − 2 states)
A schematic representation of long distance electric power transmission. From left to right: G=generator, U=step-up transformer, V=voltage at beginning of transmission line, Pt=power entering transmission line, I=current in wires, R=total resistance in wires, Pw=power lost in transmission line, Pe=power reaching the end of the transmission line, D=step-down transformer, C=consumers.
Space vector modulation (SVM) is an algorithm for the control of pulse-width modulation (PWM), invented by Gerhard Pfaff, Alois Weschta, and Albert Wick in 1982. [1] [2] It is used for the creation of alternating current (AC) waveforms; most commonly to drive 3 phase AC powered motors at varying speeds from DC using multiple class-D amplifiers.
In telecommunications, a carrier wave, carrier signal, or just carrier, is a periodic waveform (usually sinusoidal) that conveys information through a process called modulation. One or more of the wave's properties, such as amplitude or frequency, are modified by an information bearing signal, called the message signal or modulation signal .
A minority carrier device (e.g., a thyristor, a bipolar transistor, an IGBT, etc.); this uses both majority and minority carriers (i.e., electrons and electron holes). A majority carrier device is faster, but the charge injection of minority carrier devices allows for better on-state performance.