Title :
Design considerations on the DC capacitor of each chopper cell in a modular multilevel cascade inverters (MMCI-DSCC) for medium-voltage motor drives
Author :
Okazaki, Yasuo ; Matsui, H. ; Hagiwara, Manabu ; Akagi, Hirofumi
Author_Institution :
Dept. of Electr. & Electron. Eng., Tokyo Inst. of Technol., Tokyo, Japan
Abstract :
This paper describes an adjustable-speed motor with a quadratic-torque load such as fans, blowers, pumps, and compressors. The motor is characterized by being driven by the modular multilevel cascaded inverter based on doublestar chopper cells (MMCI-DSCC) A design for both mean dc-capacitor voltage and ac-voltage fluctuation in each dc capacitor used within DSCC is carried out to provide a design consideration on capacitance values of each dc capacitor. Experimental waveforms obtained from a 400-V, 15-kW downscaled system verify the validity of the theoretical analysis, and stable driving performance from a standstill to a motor mechanical speed of 1334 min-1 with quadratic-torque load.
Keywords :
DC motor drives; cascade networks; choppers (circuits); invertors; power capacitors; variable speed drives; AC-voltage fluctuation; DC capacitor; MMCI-DSCC; adjustable-speed motor; double-star chopper cells; medium-voltage motor drives; modular multilevel cascade inverters; motor mechanical speed; power 15 kW; quadratic-torque load; voltage 400 V; Capacitors; Choppers (circuits); Frequency control; Induction motors; Motor drives; Torque; Voltage control; Medium-voltage high-power motor drives; dc-capacitor voltages; multilevel inverters; quadratic-torque load;
Conference_Titel :
Energy Conversion Congress and Exposition (ECCE), 2014 IEEE
Conference_Location :
Pittsburgh, PA
DOI :
10.1109/ECCE.2014.6953861
