A power source system for supplying a load with a load voltage and a load current, said system comprising a plurality of power sources, each of said power sources producing a source voltage and a source current, and coupling means for coupling said power source together in series with said load in order to deliver the source voltages of the respective power sources to said load as said load voltages, with rates determined by the source voltages of the respective power sources and with the source current of each of said power sources being variable when each of said rates is varied between low and high normalized values, each power source comprising:
- an electric source for producing said source current as a source signal;
- and
- detecting means coupled to said electric source for detecting said source signal to produce first and second currents in accordance with a negative resistance characteristic which is such that the source current increases when the rate increases from said low normalized value toward said high normalized value;
- producing means for producing the first current as said load current;
- and
- a resistor through which said second current is caused to flow and across which a shared voltage is developed, as said source voltage, said shared voltage providing voltage of each of said power sources.