Three-dimensional space vector modulation in abc coordinates for four-leg voltage source converters

Abstract

Four-leg inverters have been selected as one of the preferred power converter topologies for applications that require a precise control of neutral current, like active filters. The main advantage of this topology lies in an extended range for the zero sequence voltages and currents. However, the addition of a fourth leg extends the space vectors from two to three dimensions, making the selection of the modulation vectors more complex. Most of the algorithms that deal with this problem require an αβγ transformation. This paper presents a new space vector modulation algorithm using abc coordinates (the phase voltages) avoiding the αβγ transformation. Thanks to the use of abc coordinates, the algorithm is much simpler and more intuitive than in αβγ representation, drastically reducing the complexity of modulation algorithm and the computational load associated to it. Index Terms-Four-leg voltage source converter, three-phase four-wire, 3D-space vector modulation, active filter. 51 V3 V11 V15 v b-ref-v a-ref v a-ref-v c-ref 52 V3 V7 V15-v a-ref + v b-ref v a-ref-v c-ref 56 V3 V7 V8-v a-ref + v b-ref v a-ref-v c-ref v c-ref 57 V9 V13 V15-v a-ref v a-ref-v b-ref v b-ref-v c-ref 58 V5 V13 V15 v a-ref-v b-ref v b-ref-v c-ref 60 V5 V7 V15 v a-ref-v b-ref v b-ref-v c-ref 64 V5 V7 V8 v a-ref-v b-ref v b-ref-v c-ref v c-ref

Optimal digital control of a three-phase four-leg voltage source inverter

“…As a new approach, abcn→ αβ0z transformation and 4 × 4T αβ0z orthonormal transformation matrix are defined and used, giving rise to independence of modulation indices from d n . Details of the 4 × 4 orthogonal transformation matrix can be found in [13,22]. The orthonormal transformation matrix T βα0z is given as…”

“…Pulse width modulation algorithms can be used by making abc → αβ coordinate transformation [16,[18][19][20] or directly in abc coordinates [22,23]. All 3-D SVPWM available strategies using abc→ αβ0 transformation use a 3 × 3 T αβ0 transformation matrix.…”

The Space Vector Modulation PWM Control Methods Applied on Four Leg Inverters

“…The 3D SVM algorithm using the abc − − frame is based on the presentation of the switching vectors as they were presented in the previous table [34][35], [69][70][71][72]. The vectors were normalized dividing them by g V .…”

“…Using split DC-link capacitors Fig. 1, where the mid-point of the DC-link capacitors is connected to the neutral of the four wire network [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48]. 2.…”

Sistema de compensación mediante filtro activo de potencia con sistema de obtención de las corrientes de referencia selectivo utilizando control 3D-3B SVPWM de la etapa de potencia. Aplicación a sistemas industriales a 4 hilos.

“…En la bibliografía pueden encontrarse este tipo de moduladores desarrollados en coordenadas de Clarke y en coordenadas del sistema A,B,C [124]- [126]. El inversor trifásico de 4 ramas se muestra en la figura 1-33 (se vuelve a representar por comodidad).…”