This thesis delves deeper into the design and implementation of a high-frequency DC to DC converter, focusing on the driving circuitry of a transformer based power conversion system operating at MHz frequencies. Because of more demand for smaller, lighter and more energy efficien
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This thesis delves deeper into the design and implementation of a high-frequency DC to DC converter, focusing on the driving circuitry of a transformer based power conversion system operating at MHz frequencies. Because of more demand for smaller, lighter and more energy efficient designs, high-frequency transformers have become an interesting and promising alternative to the standard lower frequency topologies. The project investigates two different topologies, namely: a self oscillating circuit and a GaN based full-bridge inverter. Each of these accompanied by a rectifier stage.
The final prototype successfully operates at a frequency of at least 1 MHz, generating a sinusoidal waveform at the output of the transformer. The system also meet the requirements for achieving an efficiency of 80%, and design criteria such as load independence, compact size and a minimum input voltage of 50 V DC. However, the output power has not reached the desired level of 50 V at 2 A.
The project stresses the importance of precise timing and dead time control in high-frequency switching. While the self oscillating circuit showed promise in LTSpice simulations, it was not pursued due to its dependency on the load connected. Future work should be done to explore an improved component integration, and more advanced control strategies to reach the full 100 W output capability.