Title :
Multilevel AC/DC/AC converter for AC drives
Author :
Lin, B.-R. ; Lu, H.-H.
Author_Institution :
Dept. of Electr. Eng., Nat. Yunlin Univ. of Sci. & Technol., Taiwan
fDate :
7/1/1999 12:00:00 AM
Abstract :
A novel pulse width modulation (PWM) scheme for a multilevel AC/DC/AC power converter is proposed. A power factor corrector using the hysteresis current control technique is presented to improve the power quality at the rectifier side. The circuit configuration of the adopted five-level rectifier has two AC power switches and one diode bridge. The proposed control scheme of the five-level rectifier is based on a look-up table that is implemented by programmable array logic (PAL). According to the proposed control method, the line current will follow the reference current with unity power factor. The reference supply current is derived from a DC link voltage regulator and an output power estimator. A three-level diode clamped voltage source inverter is used to reduce the output voltage harmonics and blocking voltage of each power device in each leg. The high power factor and low current distortion at the input of the rectifier and the low total harmonic distortion at the output of the inverter are verified by the experimental results
Keywords :
AC motor drives; AC-AC power convertors; AC-DC power convertors; DC-AC power convertors; PWM invertors; PWM power convertors; harmonic distortion; power conversion harmonics; power supply quality; rectifying circuits; AC motor drive applications; AC power switches; PWM scheme; blocking voltage; diode bridge; five-level rectifier; hysteresis current control technique; look-up table; multilevel AC/DC/AC power converter; output voltage harmonics; power factor corrector; power quality improvement; programmable array logic; total harmonic distortion; unity power factor; voltage source inverter;
Journal_Title :
Electric Power Applications, IEE Proceedings -
DOI :
10.1049/ip-epa:19990253