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Switching Converters commonly known as DC/DC Converters have gained tremendous popularity due to their use in variety of applications such as hybrid energy systems, hybrid vehicles, satellite applications and portable electronic devices to name a few. The main positives of using high step up converters include improving voltage gain, reduction of voltage stress and current ripple. But these converters seem to have some disadvantages like very high EMI due to reverse recovery of the boost diode and considerable amount of losses which occur due to hard switching of the boost switch. Many variations of the original boost schematic have been suggested to overcome these problems. The Zero Voltage Transition (ZVT) Boost converter and Zero Current Transition (ZCT) Boost converter are such solutions. These soft switching topologies employ an auxiliary resonant circuit which allows the boost switch to turn on and off under zero voltage and zero current conditions respectively thus reducing the switching losses. In addition, these boost converter circuits have major drawback of low power efficiency particularly at light loads due to the negative value of inductor current at light loads. In this research, a novel technique for designing a boost converter is proposed. The proposed converter employs an auxiliary circuit which allows switching of the main switch as well as the auxiliary switch under zero voltage/zero current conditions. In addition, the boost converter automatically senses the zero current across the resonant inductor, thus forcing the convertor to step automatically from Continuous Conduction Mode (CCM) to Discontinuous conduction mode (DCM) when the inductor current tries to go negative. This prevents the inductor current to go negative and hence improve convertor’s power efficiency. A novel boost convertor which steps up 200V input voltage to 400V output is designed in PSIM software with a switching frequency of 100KHz. The simulation results show that the proposed convertor has an efficiency of about 99.3% at nominal output power.