Title :
A new control method for PWM voltage-source converters under unbalanced input voltage condition
Author :
Li, Hongmei ; Li, Yang ; Wang, Xiaochen
Author_Institution :
Dept. of Electr. Eng., Hefei Univ. of Technol., Hefei, China
Abstract :
The advanced features of three-phase PWM voltage-source converter are not necessarily achieved under unbalanced input voltage conditions due to the generation of even-order harmonics at dc output and the odd-order harmonics in input currents. Both the 2nd harmonic voltage component onto the dc link and the negative sequence part of the input currents can disturb the performance of the attached inverter load and reduce the dc link capacitor lifetime. This paper presents a kind of new observer-based unbalance estimation and control method that compensates source voltage unbalances. The 2nd harmonics were eliminated and the unbalanced input currents were compensated by this new control method, respectively. The presented method also compensates the detrimental impact of delay effects and reduces the PWM switching frequency. Analytical and simulation results are presented to illustrate the effectiveness of the new observer-based control method.
Keywords :
PWM power convertors; machine control; observers; PWM switching frequency; PWM voltage-source converters; control method; even-order harmonics; observer-based unbalance estimation; unbalanced input voltage condition; Capacitors; Control systems; Power conversion; Power harmonic filters; Power system harmonics; Pulse width modulation; Pulse width modulation converters; Switching frequency; Variable speed drives; Voltage control; 2nd harmonics voltage and negative sequence current; Observer-based unbalance control method; Three-phase PWM VSC; Unbalanced input voltage;
Conference_Titel :
Electrical Machines and Systems, 2009. ICEMS 2009. International Conference on
Conference_Location :
Tokyo
Print_ISBN :
978-1-4244-5177-7
Electronic_ISBN :
978-4-88686-067-5
DOI :
10.1109/ICEMS.2009.5382945