Dynamic System Resonant Frequency Detection and Compensation Methods for WPT and Relevant Technologies

A switch mode DC-AC converter driven oscillation system, comprising:

• a primary and a secondary side circuit;
• wherein:
• the primary side circuit comprises a switch mode DC-AC converter, a primary side resonant tank, a VCO, a ZVC or ZCC detection module and a primary side controller;
• the VCO generates a square wave which is used directly as a gate driving signal of the switch mode DC-AC converter without passing through any digital circuits;
• a frequency of the gate driving signal generated by the VCO is a driving frequency of the system;
• the driving frequency of the system is neither larger nor smaller than, but always equals to an innate resonant frequency of the system accurately at steady state;
• the ZVC or ZCC detection module detects zero voltage or current crossing points of a voltage or current in the primary side resonant tank, and outputs a square wave representing the detected ZVC or ZCC points, which is input into the primary side controller;
• the whole primary side circuit is of analog circuitry where there is no digital circuits of any kind;
• the secondary side circuit comprises a secondary side resonant tank, a VCSC, a PI controller, a regulation circuit and load.