The influence of finite rated filter and energy-storage elements on the behaviour of multi-resonant single-cell converters

Finite-rate filter and energy storage elements are shown to have a large impact on the behavior of DC-DC power converters operating in the resonant mode. They change the operating area and define the low frequency characteristics. These effects are described together with their mathematical backgrounds. To optimize a resonant converter, e.g. to reduce the stresses and to improve the efficiency, the proper design of filter and energy storage components is also necessary, as well as the design of the resonant elements. As an example a zeo voltage switching multiresonant Cuk converter is investigated. It is shown that by shrinking the rating of the typical Cuk capacitor and by altering the winding ratios of the transformer and coupled inductor, the operating area will be improved