Linearisation circuit for externally controlled converter - has adder between function generator and control circuit to which additional voltage proportional to current gap duration is applied

摘要

The circuit linearises the control characteristic of an externally controlled rectifier. It has a control circuit supplied with an input voltage and supplying the inverter diodes with control pulses. The pulse control angle is a linear function of the control circuit input voltage. A function generator supplies the control circuit input voltage and is itself controlled. It controls the rectifier such that when the rectifier's output current is continuous its output voltage is proportional to the control voltage. An adder (22) is inserted between the function generator (10) and the control circuit (4). An additional voltage (Uz) is applied to it which is proportional to the time (L) of consecutive current gaps, or to the duration of current flow (F) in consecutive current pulses of the output current (I).