Switched energy resonant power supply system

A method comprising:

• providing a magnetic flux path to couple energy between an input source and an output winding;
• providing a charging terminal and a return terminal at opposite ends of the output winding, and an injection terminal at a tap between the charging terminal and the return terminal;
• exciting the magnetic flux path with a periodic flux waveform having a positive half-cycle the positive half-cycle formed from temporally adjacent first and second quarter cycles;
• during the first quarter cycle, providing a charging current path from the charging terminal to the return terminal through a series capacitance and a resistive load to transfer energy from the flux waveform to the resistive load;
• interrupting the charging current path at a predetermined point in the positive half-cycle;
• and,
• during the second quarter cycle, providing an injection current path from the return terminal to the injection terminal through the series capacitance and the resistive load to transfer energy to the input source while simultaneously dissipating energy in the resistive load.

An apparatus comprising:

• a magnetic flux path to couple energy between an input source and an output winding;
• a charging terminal and a return terminal at opposite ends of the output winding, and an injection terminal at a tap between the charging terminal and the return terminal;
• an electronically controllable charging switch that, in a conducting state, electrically connects an output node to the charging terminal, and in a non-conducting state, electrically disconnects the charging terminal from the output node;
• an electronically controllable injection switch that, in a conducting state, electrically connects the output node to the injection terminal, and in a non-conducting state, electrically disconnects the injection terminal from the output node;
• a controller operatively connected to control the conducting state of the charging switch, and further operatively connected to control the conducting state of the injection switch;
• a data store operably coupled to the controller, wherein the data store contains a program of instructions that, when executed by the controller, cause the controller to perform operations to control the charging switch and the injection switch to direct current via the output node through a series capacitance and a resistive load in response to excitation of the magnetic flux path with a periodic flux waveform having a positive half-cycle formed of temporally adjacent first and second quarter cycles, the operations comprising:
• controlling, during the first quarter cycle, the charging switch to the conducting state and the injection switch to the non-conducting state to form a charging current path from the charging terminal to the return terminal through the series capacitance and the resistive load to transfer energy from the flux waveform to the resistive load;
• interrupt the charging current path at a predetermined point in the positive half-cycle;
• and,
• controlling, during the second quarter cycle, the charging switch to the non-conducting state and the injection switch to the conducting state to form a positive injection current path from the return terminal to the injection terminal through the series capacitance and the resistive load to transfer energy to the input source while simultaneously dissipating energy in the resistive load.