Abstract: An energy-saving system for feeding an electric induction motor serving as a load, and which is operated from a 3-phase voltage power line, and in conjunction with feeding conductors for the motor includes a power-delivery sub-system operating in a magnetically linear region and coupled to the 3-phase voltage power line for providing variable feeding voltages to the induction motor, a sensing device coupled to the induction motor for generating a signal indicative of the derivatives of active power consumed by the induction motor with respect to the voltage of at least one phase provided to the induction motor, and a control apparatus coupled to the sensing device and to the power-delivery sub-system for regulating at least one of the feeding voltages, so that the derivative of the active power with respect to the voltage of that at least one phase is always substantially zero; thus for a given mechanical power output the power consumption of the induction motor is optimized, while concurrently losses in the

Abstract: A power-factor correction system for reactive power control and concomitant power factor correction adapted to cooperate with a line supplying power at a given line voltage from a power generator to an inductive load via a given path, includes a reactive power compensating device in shunt with the line supplying power, and is adapted to be connected in shunt with the inductive load.

Abstract: A power factor correcting system for compensating a lagging power factor reactance for an electric load plurality fed from at least one pair of incoming service lines, comprising, in combination: capacitors for producing leading reactive power; a series transformer, having primary and secondary winding, the secondary winding being connected in series with affected power lines; a variable transformer fed from the service lines and feeding the primaries of the series transformer; the capacitor instrumentality being fed from the affected incoming power lines with a voltage which varies in magnitude as needed, being the sum of the power line voltage plus/minus the variable series transformer secondary voltage; with the variable transformer through feeding of the primaries of the series transformer causing the required voltage variability in the series transformer secondary and subsequently in the feeding voltage applied to the capacitor; sensing instrumentality to detect presence of lagging reactive power requiri