Charging a capacitor with a current source (the inductor) prevents resistive current limiting and its associated energy loss.Īs with other converters ( buck converter, boost converter, buck–boost converter) the Ćuk converter can either operate in continuous or discontinuous current mode. This conversion is necessary because if the capacitor were connected directly to the voltage source, the current would be limited only by the parasitic resistance, resulting in high energy loss. At a short time scale, an inductor can be considered as a current source as it maintains a constant current.

The two inductors L 1 and L 2 are used to convert respectively the input voltage source ( V s) and the output voltage source ( V o) into current sources. It is connected alternately to the input and to the output of the converter via the commutation of the transistor and the diode (see figures 2 and 3). The capacitor C 1 is used to transfer energy. The main disadvantage is the high current stress on the switch.

The main advantage of this converter is the continuous currents at the input and output of the converter. It is an inverting converter, so the output voltage is negative with respect to the input voltage. Operating principleĪ non-isolated Ćuk converter comprises two inductors, two capacitors, a switch (usually a transistor), and a diode. The Ćuk converter allows energy to flow bidirectionally by using a diode and a switch. Because the power transfer flows continuously via the capacitor, this type of switcher has minimized EMI radiation. For example, the coils may share single magnetic core, which drops the output ripple, and adds efficiency. There are variations on the basic Ćuk converter. It is named after Slobodan Ćuk of the California Institute of Technology, who first presented the design. In ćuk converter, the main energy-storage component is the capacitor. Usually in DC converters, the inductor is used as a main energy-storage component. Similar to the buck-boost converter with inverting topology, the output voltage of non-isolated Ćuk converter is typically inverted, with lower or higher values with respect to the input voltage. Ćuk converter can be seen as a combination of boost converter and buck converter, having one switching device and a mutual capacitor, to couple the energy. The Ćuk converter (pronounced chook sometimes incorrectly spelled Cuk, Čuk or Cúk) is a type of buck-boost converter with zero ripple current. The switch is typically a MOSFET, IGBT, or BJT transistor. The input is left side, the output with load is right side. Comparison of non-isolated switching DC-to-DC converter topologies: Buck, Boost, Buck-Boost, Ćuk.

The isolated cuk converter