| |
An Optimized Control Technique of Cascaded H-Bridge Multilevel Active Front-Ends
| [View]
[Download]
|
| Author(s) |
Gianluca Brando, Adolfo Dannied, Andrea Del Pizzo |
| Abstract |
The paper is devoted to the investigation of a
three-phase multilevel H-bridge PWM-Rectifier operating
as a first stage of a back-to-back converter in high-power ac
drives. First, a predictive control technique is described with
reference to a 5-level converter. Starting from properly
defined reference values, the algorithm pointed out allows
the direct evaluation of the duty-cycles of all the voltage
vectors involved in the VSR modulation. By means of the
evaluated switching functions, at the end of every sampling
interval the line-currents assume values practically equal to
the imposed ones. Some unrestrictive hypotheses are
introduced in order to efficaciously simplify the analytical
expressions. As a second step, in the paper a specially
designed modulation technique is shown. In addition to low
values of dc-link voltage oscillations and of line-current
distortion in steady-state operations together with high
values of the power-factor, this modulation technique allows
to keep balanced the different capacitor voltages, by
properly using the intrinsic redundancy of the converter
topology. Numerical results are presented with reference to
some significant operative conditions in order to validate the
theoretical considerations. |
| Download |
| Filename: | T2-316.pdf |
| Filesize: | 298.8 KB |
|
| Type |
Members Only |
| Date |
Last modified 2007-03-08 by System |
| |
 |