Three-phase inverters-analysis of ability to maintain symmetrical output voltages

Author

Yao, Guijun ; Phillips, Stephen ; Norum, Lars

Author_Institution

Adv. Energy Syst. Pty Ltd., Bentley, WA, Australia

fYear

1993

fDate

15-19 Nov 1993

Firstpage

1033

Abstract

One of the important performance issues for three-phase PWM inverter technology is the maintenance of symmetrical output voltages. In this paper an equivalent circuit model for a three-phase PWM inverter is proposed. Based on this model the mechanism which distorts the symmetrical voltage output is analysed. It is revealed that the nonzero neutral current resulting from unbalanced AC outputs intrudes into the DC-link of the inverter. A proper path must be provided in the DC-link for this intruding current to circulate, otherwise its effect could destroy the symmetrical output voltage performance. A configuration, which has high inherent stability in maintaining symmetry, is suggested. Laboratory experiments are carried out on a 20 kW prototype three-phase PWM inverter and the results confirm the analysis well

Keywords

equivalent circuits; invertors; pulse width modulation; stability; 20 kW; equivalent circuit model; nonzero neutral current; stability; symmetrical output voltages; three-phase PWM inverter; three-phase inverters-analysis; unbalanced AC outputs; Bridge circuits; Circuit analysis; Electric variables control; Equivalent circuits; Impedance; Leg; Pulse width modulation; Pulse width modulation inverters; Virtual manufacturing; Voltage control;

fLanguage

English

Publisher

ieee

Conference_Titel

Industrial Electronics, Control, and Instrumentation, 1993. Proceedings of the IECON '93., International Conference on

Conference_Location

Maui, HI

Print_ISBN

0-7803-0891-3

Type

conf

DOI

10.1109/IECON.1993.339132

Filename

339132