| A bi-directional DC-DC converter is used to charge an energy storage element in most of the renewable energy systems. This thesis proposes the bi-directional DC-DC converter which employs a LLC resonant converter for the low side converter. The LLC resonant converter has outstanding efficiency and high power density. When compared to the traditional bi-directional converters, this new topology has the advantages of a simple circuit with less switching stresses resulting in less switching losses. Reduction in the size and weight of the transformer or the filter components is possible. The switches have high di/dt and dv/dt capabilities, making the switching transition fast. These advantages make the new converter topology proposed promising for auxiliary power supply in fuel cell vehicles where low cost, light weight, high reliability and high power density are required. |
