The invention relates to a converter of electrical energy or power and more particularly, a buck/boost converter.
In various topologies for converters for voltage step-up/step down and for power factor correction, there currently exist the parallel chopper or “boost” converter, the series chopper or “buck” converter, or the inductive-storage chopper or “buck-boost” converter. Each of these converters has a drawback. In the case of the parallel chopper (boost converter), the voltage at the output is always greater than the voltage applied at the input. In the case of the series chopper (buck converter), the voltage at the output is always less than the voltage applied at the input. In the case of the inductive-storage chopper, although the output voltage may be greater than or less than the voltage applied at the input, the heavy stresses on the components can render it rather unattractive.
U.S. Pat. No. 6,348,781 discloses a hybrid converter operating as a parallel or series chopper, or “buck or boost” converter. A drawback of this converter is that it has a topology in which two transistors carry out the chopping of the voltage, one transistor for each mode of operation. This converter therefore has a complicated and expensive topology.