11777 results about "Dc converter" patented technology

A grid-connected power system includes a primary power source, a back-up power source, a DC / AC inverter and a DC / DC converter. Direct current from the primary power source is supplied to the DC / AC inverter to obtain an alternating current output supplied to a utility grid when power from the utility grid is available to power a load. The output of the inverter is supplied to a selected portion of the load when power from the utility grid is unavailable to the load. Direct current from the back-up power source is supplied to the inverter through a DC / DC converter when power from the utility grid is unavailable to the load. The DC / DC converter converts the voltage of direct current from the back-up power source to direct current having a voltage compatible with the voltage of the primary power source and the inverter. The back-up power source may be charged by the primary power source or by the utility grid. Methods of providing back-up power include converting the voltage of direct current from a back-up power source to direct current of converted voltage and supplying the direct current of converted voltage to a DC / AC inverter.

The invention provides an optimal electric power converter for a DC / DC converter which variably steps up a voltage successively with an optional magnification of one to two times or more and / or step down a voltage successively with a step-down ratio of one time or less. The converter includes a first input-output part, an inductor connected with a positive or a negative electrode side of the first input-output part, plural switches, plural capacitors, a second input-output part connected with plural capacitors, and a control circuit, wherein the control circuit controls the plural switches with operation mode and makes the inductor and plural capacitors selectively functional, wherein the electric power converter is of a switched capacitance type that performs any operation out of step-up, step-down, regeneration, and continuity, and wherein the control circuit controls to have a period for which two switches out of the plural switches are simultaneously turned ON.

A DC / DC converter includes a pre-converter stage, which may include a charge pump, and a post-regulator stage, which may include a Buck converter. The duty factor of the post-regulator stage is controlled by a feedback path that extends from the output terminal of the DC / DC converter to an input terminal in the post-regulator stage. The pre-converter steps the input DC voltage up or down by a positive or negative integral or fractional value, and the post-regulator steps the voltage down by a variable amount depending on the duty factor at which the post-regulator is driven. The converter overcomes the problems of noise glitches, poor regulation, and instability, even near unity input-to-output voltage conversion ratios.