Title
An Efficient Control Strategy for a Five-Level Inverter Comprising Flying-Capacitor Asymmetric H-Bridge
Abstract
With regard to a five-level inverter comprising flying-capacitor asymmetric H-bridge, the impact on the capacitor voltage under conventional modulation approach is analyzed. Since it is sensitive to the fundamental period and the load current, it may introduce undesired low-order harmonics into the output voltage and may even break down the power switches due to the considerable fluctuation of the flying-capacitor voltage. Thus, this paper proposes a novel pulsewidth-modulation scheme with the positive and negative cross carriers, which controls the flying-capacitor voltage by utilizing the redundant switching states of the output voltages. Three modes of precharging the flying capacitor without extra equipments are presented. Moreover, the capacitance of the flying capacitor and the switching frequency of the power switches can be chosen according to the allowable fluctuation of the flying-capacitor voltage and the load current. In order to remove the overlapping of the level layers, the optimization of the line-to-line voltage waveform is proposed to synthesize the reference vector with the “nearest three-vector” approach. The theory is supported by the experimental results from the prototype.
Year
DOI
Venue
2011
10.1109/TIE.2010.2100339
IEEE Transactions on Industrial Electronics
Keywords
Field
DocType
pwm invertors,five-level inverter,power system control,asymmetric h-bridge,pulsewidth-modulation scheme,power switches,multilevel inverter,capacitors,line-to-line voltage waveform,modulation schemes,line-to-line voltage,flying-capacitor asymmetric h-bridge,negative cross carriers,positive cross carriers,capacitor-voltage balancing,flying-capacitor voltage,low-order harmonics,switches,capacitance,pulse width modulation
Inverter,Capacitance,Capacitor,Control theory,Voltage,Pulse-width modulation,Control engineering,H bridge,Voltage regulation,Engineering,Voltage divider
Journal
Volume
Issue
ISSN
58
9
0278-0046
Citations 
PageRank 
References 
6
0.56
10
Authors
2
Name
Order
Citations
PageRank
Yun Zhang1103.10
Li Sun2253.66