Soft starters of I.M. have been extensively investigated and widely used in industry in the past few years. They offer many advantages over direct on line (DOL) starting, Y-A starting, autotransformer starting, or other methods.Soft starters are part of a group of motor control techniques classified as starter voltage control techniques. The device circuit of any previous work about Softstarter consists of six thyristors connected in back to back. In spite of using a modified switching strategy for the I.M. soft starter to enhance its speed control and starting capabilities, still the main disadvantages lies in harmonic contents of the current waveforms.[l],[6]. To avoid harmonic problem this paper presents a new control technique using PLC by inserting an auto-transformer in the line to the motor, reducing or increasing the voltage at the motor terminals depend on selected taps according to a SW program in the PLC . This Softstarter has the capability to feel load changes during motor operation, and it changes the driving voltage to a suitable minimum level improved motor efficiency and energy saving are achieved by applying this technique Moreover PLC gives wide capability to control more than one motor in the same or different time for starting or stopping.
El-Sbaie, A. ,. A. (2002). POLC Soft Starter For Induction Motors. ERJ. Engineering Research Journal, 25(3), 305-317. doi: 10.21608/erjm.2002.70931
MLA
Azzam , Attia El-Sbaie. "POLC Soft Starter For Induction Motors". ERJ. Engineering Research Journal, 25, 3, 2002, 305-317. doi: 10.21608/erjm.2002.70931
HARVARD
El-Sbaie, A. ,. A. (2002). 'POLC Soft Starter For Induction Motors', ERJ. Engineering Research Journal, 25(3), pp. 305-317. doi: 10.21608/erjm.2002.70931
VANCOUVER
El-Sbaie, A. ,. A. POLC Soft Starter For Induction Motors. ERJ. Engineering Research Journal, 2002; 25(3): 305-317. doi: 10.21608/erjm.2002.70931