PROJECT TITLE :

A Timing Correction Algorithm Based Extended SVM for Three Level Neutral Point Clamped MLI in Over Modulation Zone - 2017

ABSTRACT:

The space vector modulation readied multilevel inverter (MLI) has become palpable in industrial drives. The operation of voltage-supply inverter drives within the overmodulation (OVM) mode is necessary as it patronages the extended speed vary of the ac drives. This paper proposes a timing correction algorithm (TCA) to include the OVM mode in house vector pulsewidth modulation (SVPWM) for the 3-part 3-level neutral-point-clamped (NPC) MLI drive. 1st, the boundary restriction inherited within the hexagonal area vector diagram of linear modulation (LM) is redefined/quantified as modulation depth loss factor and computed for varied values of modulation index belongs to the OVM region. Next, the suitable time correction is dole out within the switching vector timings. The TCA insinuatingly corrects these magnitude gains and losses in terms of addition and subtraction of the corrective term within the on-time of the switches. The proposed timing corrected SVPWM strategy hosts a simple assessment and a requirement-cycle recalculation procedure for determining on-times. This avoids the conventional nonlinear function and therefore the lookup table. The proposed TCA-based SVPWM is simulated in LM and OVM regions using MATLAB/Simulink, and therefore the corroboration is completed employing a field programmable gate array SPARTAN-III-3AN-XC3S40zero architecture on two-kW 3-phase 3-level NPC-MLI fed ac drive.