| 摘要 |
PURPOSE:To stabilize and control the output of an arc welding machine with quick response through digital controlling by shortening the sampling periods of taking in feedback quantit and operating the required renewal quantity from the many accumulated data for discrimination of the magnitudes thereof. CONSTITUTION:A feedback voltage signal taking-in element 14 takes in the output of a comparator 10 in sychronization with the timing pulses generated by a timing pulse generating circuit 13. At this time, a referance level and a feedback level are compared by a comparator 10, and the quantized data of 1 or 0 are taken as feedback voltage signals and are accumulated in the element 14. The input of the comparator 10 is the voltage at the contact point of a DC reactor 5 and a controlling power source 3 using a thyristor. The above-mentioned accumulated data are processed in an operating element 15 for the phase angle of zero cross synchronization at every zero cross timing pulse generated by a zero cross signal circuit 7 connected to the secondary side of a transformer 2. The output is stabilized and controlled by determining and outputting the next output control signal (thyristor firing phase angle). |
