Installing multiple step-down power transformers at the periphery of the 4160-volt area will reduce copper losses by injecting load current at more points.

Both customer inductive loads and current through inductive utility conductors require that reactive power be supplied to the distribution system. This reactive power current lags the real power current by 90 degrees ( 4. 2 ms in 60 Hz systems, 5 ms in 50 Hz systems). A feeder with 113 amps of current at a lagging power factor of 85 percent has 53 amps of inductive current added vectorally at 90 degrees to 100 amps of real power current. Both real power and inductive current are supplied from utility generation through transmission lines, substation transformers, and finally distribution feeders unless other sources of reactive power are added. Fortunately, shunt (phase-to-ground) distribution capacitors economically supply inductive current. Adding feeder capacitors to supply the 53 amps of inductive current reduces total feeder current to its real power component of 100 amps. The 13 percent feeder current reduction translates into approximately 28 percent lower I²R losses. Additionally, reducing total current frees up system capacity and reduces feeder voltage drop resulting in a “flatter”

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