Title :
Voltage balancing control of a three-phase hybrid-clamped five-level inverter based on optimal zero-sequence voltage injection
Author :
Xiaokun Wu ; Zedong Zheng ; Kui Wang ; Yongdong Li
Author_Institution :
Tsinghua Univ., Beijing, China
Abstract :
As the society pursuing for a more efficient way of using energy, the technology of multilevel converter, which aims at the field of large-power high-voltage, has been widely studied. In this paper, a newly released single phase hybrid-clamped five-level inverter has been extended to three phases. The characteristics of this topology and the switching states have been analyzed. To solve the voltage balance problem of the DC-bus capacitors and flying capacitors, a control strategy based on optimal zero-sequence voltage injection has been proposed. The strategy selects the optimal switching combinations according to their influences on the voltages of capacitors. With the injection of zero-sequence voltage, we can extend the voltage balance region of this topology compared to the existing control method. The proposed control strategy has been verified in simulations and experiments. Furthermore, the control strategy is a universal strategy which can be applied into other multilevel converters.
Keywords :
invertors; voltage control; DC bus capacitors; five level inverter; flying capacitor; hybrid clamped inverter; multilevel converter; optimal zero sequence voltage injection; three phase inverter; voltage balancing control; Capacitors; Cost function; Load modeling; Simulation; Switches; Topology; Voltage control; Converter control; Multilevel converters; Optimal control;
Conference_Titel :
Power Electronics and Applications (EPE'14-ECCE Europe), 2014 16th European Conference on
Conference_Location :
Lappeenranta
DOI :
10.1109/EPE.2014.6910768