Advantages of Buck Boost Converters | disadvantages of Buck Boost Converters
This page covers advantages and disadvantages of Buck Boost Converters. It mentions Buck Boost Converters advantages or benefits and Buck Boost Converters disadvantages or drawbacks.
What is Buck Boost Converters?
It is basically one type of DC to DC converter which has output voltage either greater or less than the input voltage magnitude. There are two types of topologies viz. inverting and non inverting. In Inverting type Output voltage polarity is different than input where as in non-inverting type output voltage polarity is same as input voltage. They are used as switching regulators which use switching element (typically one or two MOSFETs) and an energy storage device (such as inductor) to efficiently regulate input voltage to lower or higher output voltage.
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• A buck converter is known as step down converter which steps down voltage
(while stepping up current) from its input (supply voltage) to its output load.
• A boost converter is known as step up converter which steps up voltage (while stepping down current) from its input (supply voltage) to its output load.
Benefits or advantages of Buck Boost Converters
Following are the benefits or advantages of Buck Boost Converters:
➨Buck converter offers most efficient solution with smallest external components.
➨It performs step-up or step-down of voltage using minimum components.
➨It offers lower operating duty cycle.
➨It offers high efficiency across wide input and output voltage ranges.
➨It is less expensive compare to most of the converters.
Drawbacks or disadvantages of Buck Boost Converters
Following are the drawbacks or disadvantages of Buck Boost Converters:
➨Input current and charging current of output capacitor is discontinuous as it results in large filter size and more EMI issues.
➨Output is inverted which results in complex sensing and feedback circuit. As sensed voltage is negative, inverting op-amp is needed for feedback and closed loop control.
➨High gain can not be achieved with this converter type as efficiency is poor for high gain (i.e. very small duty cycle or large duty cycle).
➨There is no isolation from input side to output side which is very critical for many applications.
➨Transfer function of the converter contains right half plane as zero which introduces control complexity. Hence it is very difficult to control such converter type.