Resonant wireless power receiver circuit and control circuit and wireless power conversion method thereof

A resonant wireless power receiver circuit, comprising:

• a resonant circuit, including:
• a receiver circuit which includes at least a receiver coil;
• and
• an impedance matching circuit which is coupled to the receiver circuit, including at least one impedance matching capacitor;
• wherein the resonant circuit is configured to operably receive a wireless power to generate an AC resonant signal between a positive resonant output node and a negative resonant output node, and the AC resonant signal includes
• an AC resonant voltage, and the AC resonant voltage has
• an amplitude;
• a bridge rectifier circuit, configured to operably convert the AC resonant signal to generate a rectified output signal between a rectified output node and a ground node, wherein the rectified output signal includes a rectified output voltage and a rectified output current, wherein the bridge rectifier circuit includes at least four rectifier devices, wherein each of the four rectifier devices has a current outflow node and a current inflow node, wherein the four rectifier devices include a first rectifier device, a second rectifier device, a third rectifier device, and a forth rectifier device, and the current outflow nodes of the third rectifier device and the forth rectifier device are connected to each other at a rectified output node, and the current inflow nodes of the first rectifier device and the second rectifier device are connected to each other at a ground node, and the current inflow node of the third rectifier device and the current outflow node of the first rectifier device are connected to each other at the negative resonant output node, and the current inflow node of the forth rectifier device and the current outflow node of the second rectifier device are connected to each other at the positive resonant output node, wherein at least one of the four rectifier devices is a multi-mode switch, wherein the impedance matching capacitor is connected in series between the receiver circuit and the bridge rectifier circuit;
• and
• a control circuit, configured to operably generate a multi-mode switch control signal for controlling the multi-mode switch to operate in a Conductive Operation according to a mode selection signal, such that the voltage level of the rectified output voltage is substantially twice the amplitude of the AC resonant voltage.

A feedback control circuit, configured to operably control a resonant wireless power receiver circuit which comprises:

• a resonant circuit, including:
• a receiver circuit which includes at least a receiver coil;
• and
• an impedance matching circuit which is coupled to the receiver circuit, including at least one impedance matching capacitor;
• wherein the resonant circuit is configured to operably receive a wireless power to generate an AC resonant signal between a positive resonant output node and a negative resonant output node, and the AC resonant signal includes an AC resonant voltage, and the AC resonant voltage has an amplitude;
• a bridge rectifier circuit, configured to operably convert the AC resonant signal to generate a rectified output signal between a rectified output node and a ground node, wherein the rectified output signal includes a rectified output voltage and a rectified output current, wherein the bridge rectifier circuit includes at least four rectifier devices, wherein each of the four rectifier devices has a current outflow node and a current inflow node, wherein the four rectifier devices include a first rectifier device, a second rectifier device, a third rectifier device, and a forth rectifier device, and the current outflow nodes of the third rectifier device and the forth rectifier device are connected to each other at a rectified output node, and the current inflow nodes of the first rectifier device and the second rectifier device are connected to each other at a ground node, and the current inflow node of the third rectifier device and the current outflow node of the first rectifier device are connected to each other at the negative resonant output node, and the current inflow node of the forth rectifier device and the current outflow node of the second rectifier device are connected to each other at the positive resonant output node, wherein at least one of the four rectifier devices is a multi-mode switch, wherein the impedance matching capacitor is connected in series between the receiver circuit and the bridge rectifier circuit;
• the feedback control circuit includes:
• an error feedback circuit, configured to operably generate a voltage error feedback signal according to a voltage feedback signal related to the rectified output voltage and/or to generate a current error feedback signal according to a current feedback signal related to the rectified output current;
• and
• a switch control circuit, configured to operably generate a multi-mode switch control signal for controlling the multi-mode switch to operate at least in a portion of time in the Conductive Operation according to a voltage feedback signal related to the rectified output voltage and/or a current feedback signal related to the rectified output current so as to achieve the following functions:
• (A) such that the voltage level of the rectified output voltage is substantially twice the amplitude of the AC resonant voltage;
• or
• (B) to regulate the rectified output voltage at a level corresponding to a level of an output voltage reference signal, and/or to regulate the rectified output current at a level corresponding to a level of an output current reference signal.

A resonant wireless power conversion method, wherein a resonant circuit receives a wireless power and generates an AC resonant signal between a positive resonant output node and a negative resonant output node, wherein the AC resonant signal includes an AC resonant voltage, and the AC resonant voltage has an amplitude, and the resonant circuit includes an impedance matching capacitor;

• the resonant wireless power conversion method includes:
• controlling a bridge rectifier circuit to convert the AC resonant signal to generate a rectified output signal between a rectified output node and a ground node, wherein the rectified output signal includes a rectified output voltage and a rectified output current, wherein the bridge rectifier circuit includes at least four rectifier devices, wherein each of the four rectifier devices has a current outflow node and a current inflow node, wherein the four rectifier devices include a first rectifier device, a second rectifier device, a third rectifier device, and a forth rectifier device, and the current outflow nodes of the third rectifier device and the forth rectifier device are connected to each other at a rectified output node, and the current inflow nodes of the first rectifier device and the second rectifier device are connected to each other at a ground node, and the current inflow node of the third rectifier device and the current outflow node of the first rectifier device are connected to each other at the negative resonant output node, and the current inflow node of the forth rectifier device and the current outflow node of the second rectifier device are connected to each other at the positive resonant output node, wherein at least one of the four rectifier devices is a multi-mode switch;
• wherein the step of controlling a bridge rectifier circuit to convert the AC resonant signal to generate a rectified output signal includes:
• generating a multi-mode switch control signal according to a voltage feedback signal related to the rectified output voltage and/or a current feedback signal related to the rectified output current;
• and
• controlling the multi-mode switch to operate at least in a portion of time in the Conductive Operation by the multi-mode switch control signal, so as to achieve the following functions:
• (A) such that the voltage level of the rectified output voltage is substantially twice the amplitude of the AC resonant voltage;
• or
• (B) to regulate the rectified output voltage at a level corresponding to a level of an output voltage reference signal, and/or to regulate the rectified output current at a level corresponding to a level of an output current reference signal.