Contactless electrical energy transmission system having a primary side current feedback control and soft-switched secondary side rectifier

A contactless electrical energy transmission system for coupling a power source to a load, comprising:

• a transformer having a primary winding and a secondary winding;
• an inverter coupling said power source to said primary winding through a primary resonant circuit;
• a primary controllable switching device responsive to a switching frequency that controls flow of current through said primary winding;
• a secondary rectifier coupling said secondary winding to said load through a secondary resonant circuit that is inductively coupled to the primary resonant circuit;
• and
• a secondary control circuit that generates at least one pulse width modulated control signal for controlling the amount of energy delivered to the load, wherein the at least one pulse width modulated signal is generated in response to a voltage variation across the load and a zero current crossing through said secondary resonant circuit.

A contactless electrical energy transmission system for coupling a power source to a load, comprising:

• a transformer having a primary winding and a secondary winding;
• an inverter coupling said power source to said primary winding through a primary resonant circuit;
• a primary controllable switching device having a switching frequency that controls flow of current through said primary winding;
• a rectifier coupling said secondary winding of said transformer to said load through a secondary resonant circuit that is inductively coupled to the primary resonant circuit;
• and
• a secondary controllable switching circuit responsive to at least one pulse width modulated control signal having at least one switching element that is switched at substantially zero voltage.