D.C. voltage reduction cct. - is suitable for matching D.C. motor rotor voltage to drive voltage

摘要

Circuit arrangement for converting a direct voltage into a lower direct voltage, as may be required in d.c. motor drives for matching the speed-variable armature or rotor voltage to the drive voltage, is described. Conversion is carried out by means of a switch, periodically switching on and off, which, together with a choke in series with the switch, is connected into a series circuit comprising the direct voltage input and the load. A free-running diode is connected in parallel with the series circuit comprising the choke and load. The choke has a non-linear, i.e. sharp bend shaped magnetisation characteristic and at full load current the working region of the circuit lies on the bend of the characteristic.