How is a Cuk converter more beneficial than a buck–boost converter? When should I use a Cuk converter?
The Canonical Cell forms the basis of analyzing switching circuits, but the energy transport mechanism forms the foundation of the building blocks of such converters. The Buck converter may consequently be seen as a Voltage to Current converter, the Boost as a Current to Voltage converter, the Buck-Boost as a Voltage-Current-Voltage and the CUK as a Current-Voltage-Current converter. All other switching converter MUST fall into one of these configurations if it does not increase the switching stages further for example into a V-I-V-I converter which is difficult to realize through a single controlled switch. It does not require an explanation that a current source must be made to deliver its energy into a voltage sink and vice-versa. A voltage source cannot discharge into a voltage sink and neither can a current source discharge into a current sink. The first would cause current stresses while the latter results in voltage surges. This rule is analogous to the energy exchange between a source of Potential Energy (Voltage of a Capacitor) and a sink of Kinetic Energy (Current in an Inductor) and vice-versa. Both can however discharge into a dissipative load, without causing any voltage or current amplification. The resonant converters also have to agree to some of these basic rules.
Features of a buck - boost converter are
• Pulsed input current, requires input filter.
• Pulsed output current increases output voltage ripple
• Output voltage can be either greater or smaller than input voltage.
It will be desirable to combine the advantages of these basic converters into one converter. CuKconverter is one such converter. It has the following advantages.
• Continuous input current.
• Continuous output current.
• Output voltage can be either greater or less than input voltage.
(If you want to see the advantages or disadvantages of topologies, I think you should simulate these. By this way, you can see current and voltage ripples of topologies. )
The point is energy storage staff in the circuit. These indirect converters should have a storage for their operation. The current supports the transfer of the energy. Therefore, the mode of swathes just decides the direction of current and circuit structure. We are using the transient energy flow as a power conversion. This is the standpoint of physics in a circuit.
1. Cuk converter uses L-C type filter, so peak-peak ripple current of inductors are less as compared to the Buck-Boost converter.
2.In CuK converter, when switch is closed then capacitor 'C' provides energy to the load as well as inductive filter. But when switch is open then energy stored in the filter inductor is fed back to the load. Where as in case of Buck-Boost converter, when switch is closed then source is disconnected from the load and when switch is open then energy stored in the inductor is fed back to the source.
The obvious advantage is the continous input and output currents for the CUk converter
Anup
In mechatronics, Cuk converter use a capacitor as its main energy-storage component, different most other typical buck converters that use an inductor.
Eventhough buck boost converter is cheaper than cuk converter, limitations such as discontinuous input current, high peak current in power components, poor transient response etc of buck-boost makes it less efficient
hence cuk is always preferred over buck boost
An important advantage of Cuk topology is a continuous current at both the input and the output of the converter. Disadvantages of the Cuk converter are a high number of reactive components and high current stresses on the switch
How do I select max current and min current for chuck converter output.