One-sided parallel LLC power converter

A power converter comprising:

• a primary circuit comprising:
• a common node electrically coupled to a high-voltage source;
• a first primary LC circuit electrically coupled to the common node and to a first primary node;
• a second primary LC circuit electrically coupled to the common node and to a second primary node, the second primary LC circuit in parallel electrically with the first primary LC circuit, the first and second primary LC circuits having the same or about the same primary LC resonance frequency;
• a primary inductor having a first terminal electrically coupled to the first primary node and a second terminal electrically coupled to the second primary node;
• a first primary circuit switch electrically coupled to the first primary node, the first primary circuit switch having a closed state where the first primary switch is electrically coupled to the first primary node and to ground, the first primary circuit switch having an open state where the first primary circuit switch is electrically decoupled from the first primary node;
• and
• a second primary circuit switch electrically coupled to the second primary node, the second primary circuit switch having a closed state where the second primary switch is electrically coupled to the second primary node and to ground, the second primary circuit switch having an open state where the second primary circuit switch is electrically decoupled from the second primary node;
• a secondary circuit in electrical communication with the primary circuit, the secondary circuit comprising:
• a secondary inductor electromagnetically coupled to the primary inductor to form a transformer;
• a first secondary circuit switch electrically coupled to a first secondary inductor node, the first secondary node electrically coupled to a first terminal of the secondary inductor, the first secondary circuit switch having a closed state where the first secondary switch is electrically coupled to the first secondary node and to ground, the first secondary circuit switch having an open state where the first secondary circuit switch is electrically decoupled from the first secondary node;
• a second secondary circuit switch electrically coupled to a second secondary inductor node, the second secondary node electrically coupled to a second terminal of the secondary inductor, the second secondary circuit switch having a closed state where the second secondary switch is electrically coupled to the second secondary node and to ground, the second secondary circuit switch having an open state where the second secondary circuit switch is electrically decoupled from the second secondary node;
• a low-pass filter electrically coupled to the first and second secondary nodes;
• a low-voltage output node electrically coupled to an output of the low-pass filter;
• and
• a controller in electrical communication with the first and second primary circuit switches and with the first and second secondary circuit switches, the controller configured to:
• operate the first and second primary circuit switches at about the primary LC resonance frequency;
• and
• operate the first and second secondary circuit switches at about the primary LC resonance frequency,
• wherein the controller includes a charge-sharing circuit that is electrically coupled to a charge-sharing switch, the charge-sharing switch electrically coupled to the first and second secondary circuit switches.

A power converter comprising:

• a primary circuit comprising:
• a common node electrically coupled to a high-voltage source;
• a first primary LC circuit electrically coupled to the common node and to a first primary node;
• a second primary LC circuit electrically coupled to the common node and to a second primary node, the second primary LC circuit in parallel electrically with the first primary LC circuit, the first and second primary LC circuits having the same or about the same primary LC resonance frequency;
• a primary inductor having a first terminal electrically coupled to the first primary node and a second terminal electrically coupled to the second primary node;
• a first primary circuit switch electrically coupled to the first primary node, the first primary circuit switch having a closed state where the first primary switch is electrically coupled to the first primary node and to ground, the first primary circuit switch having an open state where the first primary circuit switch is electrically decoupled from the first primary node;
• and
• a second primary circuit switch electrically coupled to the second primary node, the second primary circuit switch having a closed state where the second primary switch is electrically coupled to the second primary node and to ground, the second primary circuit switch having an open state where the second primary circuit switch is electrically decoupled from the second primary node;
• a secondary circuit in electrical communication with the primary circuit, the secondary circuit comprising:
• a secondary inductor electromagnetically coupled to the primary inductor to form a transformer;
• a secondary circuit capacitor in parallel electrically with the secondary inductor to form a secondary LC circuit, the secondary circuit capacitor comprising a variable capacitor;
• a first secondary circuit switch electrically coupled to a first secondary inductor node, the first secondary node electrically coupled to a first terminal of the secondary inductor, the first secondary circuit switch having a closed state where the first secondary switch is electrically coupled to the first secondary node and to ground, the first secondary circuit switch having an open state where the first secondary circuit switch is electrically decoupled from the first secondary node;
• a second secondary circuit switch electrically coupled to a second secondary inductor node, the second secondary node electrically coupled to a second terminal of the secondary inductor, the second secondary circuit switch having a closed state where the second secondary switch is electrically coupled to the second secondary node and to ground, the second secondary circuit switch having an open state where the second secondary circuit switch is electrically decoupled from the second secondary node;
• a low-pass filter electrically coupled to the first and second secondary nodes;
• a low-voltage output node electrically coupled to an output of the low-pass filter;
• and
• a controller in electrical communication with the first and second primary circuit switches and with the first and second secondary circuit switches, the controller configured to:
• operate the first and second primary circuit switches at about the primary LC resonance frequency;
• and
• operate the first and second secondary circuit switches at about the primary LC resonance frequency,
• wherein:
• the controller includes a voltage regulation circuit that compares an output voltage at the low-voltage output node with a reference voltage,
• the voltage regulation circuit increases a capacitance of the variable capacitor when the output voltage is greater than the reference voltage,
• the voltage regulation circuit decreases a capacitance of the variable capacitor when the output voltage is less than the reference voltage, and
• the controller includes a primary zero-voltage switching circuit that adjusts a duty cycle of the first and second primary circuit switches so that the first and second primary circuit switches are in phase with the first and second secondary circuit switches, respectively, when the capacitance of the variable capacitor is adjusted.