| Abstract |
This paper presents the complete theoretical analysis, simulation and design optimisation of a Full-Bridge Zero-Voltage-Switched Phase-Shift (FB-ZVS-PS) DC-DC converter with an LCC auxiliary circuit, working with a frequency of 250kHz and with an output power of 1kW. The converter uses a voltage capacitor divider to create half of the input voltage in one terminal of the auxiliary inductor. The voltage at the inductor terminals will, therefore, oscillate between -VI/2 and +VI/2, producing an additional current reinforcing the primary current during the passive-to-active transition and increasing the energy available to achieve ZVS. This way, it is possible to design FB-PS-ZVS DC/DC converter without using a commutating inductor in series with the power transformer, avoiding the problems related with the effective duty cycle reduction. Furthermore, it is shown that, by properly design of LCC circuit, the ZVS range and the effective-duty-cycle can be optimised, without significant overall penalties. |
