Circuit arrangement for controlling the energization of a load from a plurality of current sources

Claim 1

In a system for energizing a load with a substantially constant voltage from a plurality of direct-current sources connected in parallel thereacross with interposition of respective isolating diodes, each source including a current generator with an output voltage which is substantially independent of output current up to a certain maximum current, each source further including voltage-regulating means with a feedback connection across the load for comparing the load voltage with a reference level and for controlling said current generator to maintain the output voltage thereof at said reference level, the improvement wherein said voltage-regulating means comprises: comparison means with a first input circuit including said feedback connection supplying a first input voltage proportional to load voltage and a second input circuit connected to a supply of second input voltage representing said reference level, said generator having a control input connected to said comparison means; current-sensing means in series with said generator; and electronic switch means responsive to said current-sensing means and connected across part of one of said input circuits for modifying the ratio of said input voltages to raise the effective value of said reference level upon the output current of said generator dropping below a predetermined minimum magnitude, thereby increasing the contribution of said generator to the energization of the load.