CUK TYPE DIRECT/DIRECT VOLTAGE CONVERTER AND MAINS SUPPLY WITH DIRECT CONVERSION ACHIEVED WITH A CONVERTER SUCH AS THIS

摘要

A Cuk-type direct/direct or DC/DC voltage converter which is comprised of primary and secondary sides. These primary and secondary sides both contain a series circuit which is a made up of an inductance coil, a capacitor and a winding. The primary side also contains an active switch-over element and the secondary side contains a passive switch-over device. A control circuit delivers control pulses to the active switch-over element that are variable in width based on a function of an error signal. This control circuit comprises a slopes generator and a comparator which compares the instantaneous level of the slopes with a threshold level as a function of the error signal. The gradient of each slope varies as a function of the input voltage and is independent of the output voltage. The threshold level is a function of the error signal. The gradient of the slopes generator is controlled by a control voltage tapped at the mid point of a divider bridge which is series mounted wiuth a voltage reference. The divider bridge-voltage reference set has applied thereto a voltage which is equal to or proportionate to the input voltage. The outpout voltage produced by the converter under the control of the control circuit is made essentially independent of the input voltage. This open loop regulation provides for stability of the system, and thereby provides a response time which is below that of standard Cuk converters.