Montero-Robina P. , Gordillo F. , GÓMEZ-ESTERN AGUILAR, FABIO, Salas F.
No
Int. J. Electr. Power Energy Syst.
Article
Científica
5.659
1.544
01/01/2021
000571931600009
2-s2.0-85089245122
In power converters, the modulation stage commands the switching devices to drive the converter outputs to the voltage required by the inner controllers in order to achieve their objectives. However, in multilevel converters, the modulation may be in charge of an additional goal since it also has to tackle with the capacitor voltage balancing issue. This paper formulates the modulation of multilevel three-phase power converters, specifically five-level diode-clamped converters (DCC), as a mixed-integer linear optimization problem. In this paper, it is shown that the presented optimization problem can deal with the capacitor voltage balance at the same time that the number of commutations is minimized. The problem is solved offline and its solution is stored in a lookup table to be used during normal operation. Then, an online procedure to obtain the levels that modulate each phase from the lookup table is given. Comparisons with model predictive control, space-vector-based algorithms and other modulation approaches are presented in simulations. Several experimental results are presented showing the feasibility of this approach with changes in the operating conditions. © 2020 Elsevier Ltd
Integer programming; Model predictive control; Modulation; Predictive control systems; Table lookup; Vector spaces; Capacitor voltage balance; Capacitor voltage balancing; Mixed integer linear programming; Mixed-integer linear optimizations; Multilevel converter; Operating condition; Optimization problems; Three-phase power converter; Power converters