A Non-Isolated Cascaded Buck-Boost Converter with Improved Voltage Balancing with Respect to Ground and Reduced Common Mode Noise

In this paper the investigation of a modified version of the non-isolated cascaded buck-boost converter is presented in order to achieve a better voltage balancing of the converter with respect to ground. This should reduce common mode noise due to the parasitic capacitive coupling between the switching nodes, heat sinks and protective earth. Measurements confirm the balancing capabilities of the described symmetry circuit, leading to significantly reduced common mode noise.