This calls for new technologies in order to miniaturize the power electronics of today. One way to do this is by increasing the switching frequency dramatically and develops very high frequency switch mode power supplies. If these converters can be designed to operate efficiently, a huge size, weight and cost reduction can be achieved due to the smaller energy storing elements needed at these frequencies.
Therefore, increasing the switching frequency of power converters into the Very High Frequency range (VHF, 30-300 MHz) is promising solutions for the future power electronics.
The main contributions from this work are:
- Further investigation of advanced gate drive for very high frequency converters.
- Proof of principle that the gate drives also work for synchronous rectification and high side gate drives
- The world’s first VHF half bridge converter operating at more than a few volts
- Development of a rearranging method which significantly reduces the voltage stress and improves the efficiency
- The first direct comparison of toroid, spiral and solenoid PCB embedded inductors
- Presentation of conducted and radiated EMI measurements with and without shield and burst mode control
- Development of prototypes that clearly shows the potential of VHF converters
Figure 1: The world’s first discrete VHF class DE converter
Figure 2: Resonant converters with the different structures for PCB embedded inductors
Figure 3: 20 W converters operating at 37 MHz
Figurer 4: A 20 W prototype based on a 27 MHz DE converter compared with an equivalent commercial product
Table 1: Performance improvements compared to a commercial product
Contact Person
Zhe Zhang
Associate Professor
Technical University of Denmark
E-mail: zz@elektro.dtu.dk