Compensation circuit for load with varying current - keeps total load and compensator current constant eliminating voltage fluctuations in parallel connected loads

摘要

The application is to parallel connected loads (1,2,3) fed from a common constant voltage supply (4). The object is to avoid interference with the operation of the other loads (1,2) if one (3) has a rapidly and frequently varying current demand. The current flow (JL) into the variable load (3) is constantly measured and its magnitude used to set the current (JS) in an additional circuit (7) in order that the total current (JK) to the load (3) remains at a constant value. Voltage fluctuations on the other loads (1,2) are thus eliminated. The variable current drain (7) forms part of a compensator circuit (6). In it the total current (JK) is typically compared (9) with a set reference (Jr), and the error used to control the drain current (JS). The total current may be varied for long term load changes by comparing (13) the maximum load current with the minimum necessary drain current, and,through a time delay (14), adjusting the reference (Jr).