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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.
The direct-quadrature-zero (DQZ, DQ0 [1] or DQO, [2] sometimes lowercase) transformation or zero-direct-quadrature [3] (0DQ or ODQ, sometimes lowercase) transformation is a tensor that rotates the reference frame of a three-element vector or a three-by-three element matrix in an effort to simplify analysis.
Another way to understand this is that the equation + + = defines a plane in a euclidean three coordinate space. The alpha-beta coordinate space can be understood as the two coordinate space defined by this plane, i.e. the alpha-beta axes lie on the plane defined by I a + I b + I c = 0 {\displaystyle I_{a}+I_{b}+I_{c}=0} .
That is, the spheres of radius three around code words form a partition of the vector space. G 23 is a 12-dimensional subspace of the space F 23 2. The automorphism group of the perfect binary Golay code G 23 (meaning the subgroup of the group S 23 of permutations of the coordinates of F 23
The third category, space-vector-based modulation, generates PWM load line currents that equal load line currents, on average. Valid switching states and time selections are made digitally based on space vector transformation. Modulating signals are represented as a complex vector using a transformation equation.
From the end of 1990s several papers have been published about DTC and its modifications such as space vector modulation, [20] which offers constant switching frequency. In light of the mid-2000s expiration of Depenbrock's key DTC patents, it may be that other companies than ABB have included features similar to DTC in their drives. [citation ...
The Hadamard code is a linear code, and all linear codes can be generated by a generator matrix.This is a matrix such that () = holds for all {,}, where the message is viewed as a row vector and the vector-matrix product is understood in the vector space over the finite field.
Orthogonal Time Frequency Space (OTFS) is a 2D modulation technique that transforms the information carried in the Delay-Doppler coordinate system. The information is transformed in a similar time-frequency domain as utilized by the traditional schemes of modulation such as TDMA , CDMA , and OFDM . [ 1 ]