Lifetime-Based Power Routing of a Quadruple Active Bridge DC/DC Converter

Medium-voltage dc/dc converters have recently acquired importance in the smart grid and dc distribution framework. However, several open issues remain with regard to the reliability of such systems. This paper proposes a modular isolated dc/dc converter with multiple quadruple active bridge building blocks. This design, in combination with a virtual resistor-based control, weights the paths depending on the components wear-out and can balance the stress of the semiconductors in the attempt of extending overall system lifetime. The effectiveness of the approach is demonstrated in simulations and supported with measurements on a small-scale demonstrator with open modules, built in order to verify in real time the capability of controlling the thermal stress of the semiconductors.