Open AccessMinimum signal modulation scheme based on a single carrier for interleaved operation of parallel phase legs in voltage source converters
Author(s) -
Capella Gabriel J.,
Gabiola Igor,
Pou Josep,
Zaragoza Jordi,
Ceballos Salvador,
Agelidis Vassilios G.
Publication year - 2014
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2013.0545
Subject(s) - pulse width modulation , interleaving , digital signal processing , computer science , ripple , electronic engineering , converters , digital signal processor , inverter , modulation (music) , matlab , signal (programming language) , power (physics) , voltage , control theory (sociology) , computer hardware , electrical engineering , engineering , physics , control (management) , quantum mechanics , artificial intelligence , programming language , operating system , acoustics
Connecting legs in parallel is a common way to increase the output current of a power converter. Interleaving the carriers used to modulate the reference signals for each leg leads to a reduction in the output current ripple without resorting to increasing the switching frequency. A whole set of shifted carriers is required if interleaved pulse‐width modulators (PWMs) are used. Implementing this by means of a digital signal processor (DSP) means that the higher the number of carriers, the higher the number of DSP timing resources required. Provided that the latter are usually limited, this could be a drawback when increasing the number of interleaved carriers. This study presents the implementation of a PWM scheme where all modulators use the same carrier offering the same results as if a set of n interleaved carriers were used. Since the proposed algorithm takes maximum benefit from the PWM units available in a DSP, a higher number of legs connected in parallel can be controlled without adding any external processing hardware. A MATLAB/Simulink model has been set up for simulation purposes. Selected experimental results obtained from a three‐leg single‐phase inverter are reported, confirming the effectiveness of the proposed implementation.