Real-Time Algorithm for Minimizing THD in Multilevel Inverters With Unequal or Varying Voltage Steps Under Staircase Modulation
Yu Liu
Hoon Hong
Huang, A.Q.
Dept. of Electr. Eng., North Carolina State Univ., Raleigh, NC;
This paper appears in: Industrial Electronics, IEEE Transactions on
Publication Date: June 2009
Volume: 56,
Issue: 6
On page(s): 2249-2258
ISSN: 0278-0046
INSPEC Accession Number: 10713193
Digital Object Identifier: 10.1109/TIE.2009.2015360
First Published: 2009-02-24
Current Version Published: 2009-06-02
Abstract
Different modulation methods have been proposed to control the multilevel inverters. This paper focuses on the staircase modulation that is very popular for multilevel inverters with low switching frequencies. Nonreal-time algorithms for the staircase modulation cannot be applied practically in multilevel inverters with varying voltage steps, since the sizes of lookup tables would be huge. We propose a real-time algorithm for multilevel inverters with unequal or varying voltage steps under the staircase modulation. The algorithm results in the minimal total harmonic distortion (THD) of the output voltage of the inverter, which is proved by rigorous mathematical derivations in this paper. A new expression of THD is presented to simplify the derivation significantly. Computational complexity of the algorithm is analyzed to estimate the time cost of the calculation. We implemented the algorithm on a digital signal processor and provide experimental results that verify the performance of the proposed algorithm.
Index
Terms
Available to subscribers and IEEE members.
References
Available to subscribers and IEEE members.
Citing Documents
Available to subscribers and IEEE members.
Cart
