Electric power apparatus comprising converter, filter, regulator, and means for dynamically stabilizing the filter

Claim 1

In combination: a. electric power conversion apparatus comprising controlled rectifying means serially connected via a filter to a DC bus which in turn is adapted to be connected to an electric power load, i. said rectifying means being adapted to be connected to an electric power source and being operative to energize said filter with an undulating voltage whose average magnitude depends on the magnitude of a variable control signal supplied to the rectifying means, ii. said filter having series inductance and parallel capacitance elements of appropriate values to attenuate the ripple in said undulating voltage, whereby a relatively smooth unipolarity output voltage is applied to said DC bus; b. a first voltage regulating loop comprising proportional feedback means for deriving a first feedback signal from said undulating voltage and means for providing an error signal representing the magnitude difference between a given reference signal and said first feedback signal; and c. a second voltage regulating loop comprising rate feedback means connected to said DC bus for deriving a second feedback signal from said output voltage and means for supplying said rectifying means with a control signal whose magnitude depends on the difference between said error signal and said second feedback signal.