A Discontinuous PWM Method for Balancing the Neutral Point Voltage in Three-Level Inverter-Fed Variable Frequency Drives

Author

Ben-Brahim, Lazhar

Author_Institution

Dept. of Electr. Eng., Qatar Univ., Doha

Volume

23

Issue

4

fYear

2008

Firstpage

1057

Lastpage

1063

Abstract

The paper describes a new discontinuous carrier-based pulsewidth modulation (PWM) method for use in variable frequency drives (VFD) driven by three-level inverters. The method introduces three different switching patterns for the full range of operating speeds. Depending on the actual operating speed, the proposed algorithm is developed to select the most suitable PWM switching pattern that improves the VFD performance. This results in low imbalance in the DC-link capacitor voltage, and low current distortions without increasing switching losses. Theory, simulation, and experimental results are presented.

Keywords

PWM invertors; electric drives; DC-link capacitor voltage; PWM switching pattern; discontinuous carrier-based PWM method; low current distortions; neutral point voltage; pulsewidth modulation method; three-level inverter-fed variable frequency drives; Capacitors; Drives; Frequency; Pulse inverters; Pulse width modulation; Pulse width modulation inverters; Space vector pulse width modulation; Switching loss; Thyristors; Voltage; Discontinuous pulsewidth modulation; energy saving; gate turn-off thyristor (GTO); neutral point (NP) voltage; neutral point clamped (NPC); pulsewidth modulation (PWM); three-level inverter; variable frequency drives (VFD);

fLanguage

English

Journal_Title

Energy Conversion, IEEE Transactions on

Publisher

ieee

ISSN

0885-8969

Type

jour

DOI

10.1109/TEC.2008.2001435

Filename

4675800