Title :
A new PWM type GTO Scherbius industrial device with high power factor
Author :
Zutong, Zhu ; Dingguo, Hong ; Yusheng, Chen
Author_Institution :
Dept. of Electr. & Autom. Eng., Beijing Univ. of Sci. & Technol., Beijing, China
Abstract :
A Scherbius device is presented with a gate turnoff (GTO)-type AC motor speed control device and the advantages of simple construction, convenient control, high power factor, and low cost. The invertor capacity of this device is reduced to about 40% of that of a common Scherbius system with the same load. There is only one gate turn-off element connected in parallel with the direct current side of the inverter in this device. A symmetric pulse-width modulation (PWM) control is adopted for the device under a certain fixed inverting firing angle of the inverter, instead of adjusting the inverting firing angle. In such a manner the inverted voltage and the motor speed can be controlled with a higher power factor and a lower influence of the harmonic current on the power supply compared with the common Scherbius system. This device is suitable for saving energy in ventilators and pumps.<>
Keywords :
AC motors; invertors; machine control; pulse width modulation; thyristor applications; velocity control; AC motor speed control; GTO Scherbius industrial device; PWM; firing angle; gate turn-off; harmonic current; invertor capacity; machine control; power factor; power supply; pumps; speed control; thyristor applications; ventilators; AC motors; Construction industry; Costs; DC motors; Pulse inverters; Pulse width modulation; Pulse width modulation inverters; Reactive power; Velocity control; Voltage control;
Conference_Titel :
Industry Applications Society Annual Meeting, 1989., Conference Record of the 1989 IEEE
Conference_Location :
San Diego, CA, USA
DOI :
10.1109/IAS.1989.96742
