Finished device:

This project is a different take on a boost converter (turns a low DC voltage into a higher one). I used the large voltage swing of an LC oscillator which can be sustained by adding energy with a low voltage.

The basic principle of operation of the circuit is that an oscillator is tuned to the exact resonance frequency of the LC oscillator (which can be found mathematically) and then for each pulse of the oscillator, a transistor is switched to allow for the capacitor to charge, which continues the oscillation.

Circuit Diagram:

After making the circuit, I tested it fully by finding the time taken to fully charge the 200uF capacitor, probing the LC oscillator waveform and loading the circuit with many different currents and measuring the output voltage and pk-pk voltage of the oscillator.

LC oscillator voltage:

Capacitor voltage at initial circuit turn on: (charge time highlighted)

Graph of Pk-Pk and Output voltage vs current and circuit diagram used.

In this circuit, Meter 1 shows the output voltage and Meter 2 will measure current where every volt across the resistor is one amp flowing through it

Using these results and the trendline of the graph, I then calculated the theoretical maximum power output of the circuit and charge time of the capacitor, which closely mimic real behavior of the circuit.