CN-121984251-A - Staggered parallel voltage-stabilizing wireless charging system

CN121984251ACN 121984251 ACN121984251 ACN 121984251ACN-121984251-A

Abstract

The invention discloses a staggered parallel voltage-stabilizing wireless charging system, which belongs to the field of wireless charging and comprises a primary side and a secondary side. The primary side comprises a direct current power supply V IN , an inverter circuit, a primary side compensation and a transmitting coil for transmitting energy to the secondary side, and the secondary side comprises a receiving coil, a secondary side compensation circuit, a rectifying circuit and two voltage stabilizing circuits which are connected in parallel in a staggered manner and used for receiving the energy of the primary side and realizing power regulation of output. The system of the invention does not depend on primary side power adjustment, realizes the control of output power only through the voltage stabilizing circuit of the secondary side, does not need a communication system between the primary side and the secondary side, has no communication delay and has simple structure. The system leads the two parallel voltage stabilizing circuits to shunt the output current through the current sharing design, thereby reducing the current stress of the switching tube. And through the phase control between two voltage stabilizing circuits, output voltage and output current ripple can also be reduced, and then the requirement on output capacitance is reduced.

Inventors

LIU SHANGJIANG
JI FEI
GUAN YUE

Assignees

中国电子科技集团公司第五十八研究所

Dates

Publication Date: 20260505
Application Date: 20260130

Claims (9)

1. The staggered parallel voltage-stabilizing wireless charging system is characterized by comprising a primary side and a secondary side; The primary side comprises a direct current power supply V IN , an inverter circuit, an inverter controller, primary side compensation and a transmitting coil, and the secondary side comprises a receiving coil, secondary side compensation, a rectifying circuit, a voltage stabilizing circuit I and a voltage stabilizing circuit II; The voltage of the direct current power supply V IN is converted into high-frequency alternating current through an inverter circuit; The high-frequency alternating current output by the inverter circuit is added to a primary side resonance circuit formed by primary side compensation and a transmitting coil, and the transmitting coil transmits energy to a receiving coil through magnetic coupling resonance; After the receiving coil receives energy from the transmitting coil, the receiving coil and the secondary side compensation form a secondary side resonance circuit, and the received alternating current is input into a rectification circuit; The rectification circuit adopts a non-control rectification structure to convert received high-frequency alternating current into direct current V D , the voltage stabilizing circuit I and the voltage stabilizing circuit II convert V D into set output voltage V OUT , the two voltage stabilizing circuits have the same structure and are synchronous buck-structure switch converters, and peak current mode control is adopted to facilitate current sharing control between the two circuits.
2. The interleaved parallel regulated wireless charging system according to claim 1, wherein the inverter circuit comprises switching tubes Q1, Q2, Q3, Q4 each having a gate terminal connected to an inverter controller; The drain end of the switching tube Q1 and the drain end of the switching tube Q3 are both connected with the positive end of the direct current power supply V IN , and the source end of the switching tube Q2 and the source end of the switching tube Q4 are both connected with the negative end of the direct current power supply V IN ; The source end of the switching tube Q1 is connected with the drain end of the switching tube Q2, and the source end of the switching tube Q3 is connected with the drain end of the switching tube Q4.
3. The interleaved voltage regulating wireless charging system of claim 2 wherein the primary side compensation comprises an inductor L P , a capacitor C P and a capacitor C1, wherein a first terminal of the inductor L P is connected to both the source terminal of the switch Q1 and the drain terminal of the switch Q2, a second terminal of the inductor L P is connected to both the first terminal of the capacitor C1 and the first terminal of the capacitor C P , a second terminal of the capacitor C P is connected to both the source terminal of the switch Q3 and the drain terminal of the switch Q4, a second terminal of the capacitor C1 is connected to the first terminal of the transmitting coil, and a second terminal of the transmitting coil is connected to the second terminal of the capacitor C P .
4. The interleaved voltage regulated wireless charging system according to claim 1, wherein the rectifying circuit comprises diodes D1, D2, D3, D4 to convert the received high frequency ac power to dc power V D ; The cathode of the diode D1 is connected with the cathode of the diode D2, and the anode of the diode D3 is connected with the anode of the diode D4.
5. The interleaved stabilized wireless charging system according to claim 4 wherein the secondary compensation comprises an inductance L S , a capacitance C S , and a capacitance C2, wherein a first end of the inductance L S is connected to a second end of the capacitance C2 and a first end of the capacitance C S simultaneously, a second end of the inductance L S is connected to an anode of the diode D1 and a cathode of the diode D3 simultaneously, a second end of the capacitance C S is connected to an anode of the diode D2 and a cathode of the diode D4 simultaneously, a first end of the capacitance C2 is connected to a first end of the receiving coil, and a second end of the receiving coil is connected to a second end of the capacitance C S .
6. The interleaved parallel regulated wireless charging system according to claim 5, wherein the first voltage regulating circuit comprises switching tubes Q5 and Q6, an inductance L D1 , a resistance R S1 , and a current sampling operational amplifier CS1, and the second voltage regulating circuit comprises switching tubes Q7 and Q8, an inductance L D2 , a resistance R S2 , and a current sampling operational amplifier CS2; The drain end of the switching tube Q5 is connected with direct current V D , the source end of the switching tube Q5 and the drain end of the switching tube Q6 are connected with the first end of an inductor L D1 together, the source end of the switching tube Q6 is grounded, the second end of the inductor L D1 is connected with the first end of a resistor R S1 , the second end of the resistor R S1 outputs current I O1 , the two input ends of a current sampling operational amplifier CS1 are respectively connected with the first end and the second end of the resistor R S1 , and the output end is connected with a PWM controller; The drain end of the switching tube Q7 is connected with direct current V D , the source end of the switching tube Q7 and the drain end of the switching tube Q8 are connected with the first end of an inductor L D2 together, the source end of the switching tube Q8 is grounded, the second end of the inductor L D2 is connected with the first end of a resistor R S2 , the second end of the resistor R S2 outputs current I O2 , the two input ends of a current sampling operational amplifier CS2 are respectively connected with the first end and the second end of the resistor R S2 , and the output end is connected with a PWM controller; The PWM controller outputs a driving signal V g5 to the gate end of the switching tube Q5, outputs a driving signal V g6 to the gate end of the switching tube Q6, outputs a driving signal V g7 to the gate end of the switching tube Q7, and outputs a driving signal V g8 to the gate end of the switching tube Q8; The first voltage stabilizing circuit and the second voltage stabilizing circuit adopt peak current mode control, current sampling operational amplifiers CS1 and CS2 collect current signals of inductances L D1 and L D2 and input the current signals to a PWM controller, a voltage dividing network formed by resistors R FB1 and R FB2 samples output voltage to serve as input of an error amplifier, and output signals of the error amplifier are input to the PWM controller after loop compensation and are used for being compared with the current sampling signals to generate switching tube control signals.
7. The interleaved parallel regulated wireless charging system according to claim 6, wherein the switching tube driving signals of said first and second voltage stabilizing circuits have the same frequency, a phase difference of 180 °, a phase difference of V g5 and V g7 of 180%, and a phase difference of V g6 and V g8 of 180, and ripple of the output current and output voltage is reduced by controlling phase errors of said first and second voltage stabilizing circuits, while the requirement for output capacitance is reduced.
8. The interleaved stabilized wireless charging system according to claim 6 further comprising a capacitor C O1 , a resistor R FB1 , a resistor R FB2 , an error amplifier, a capacitor C COMP , a capacitor C COMP_P , a resistor R COMP ; the first end of the capacitor C O1 is simultaneously connected with the second end of the resistor R S1 and the second end of the resistor R S2 , the second end of the capacitor C O1 is grounded, the first input end of the error amplifier is simultaneously connected with the second end of the resistor R FB1 and the first end of the resistor R FB2 , the first end of the resistor R FB1 is connected with the first end of the capacitor C O1 , and the second end of the resistor R FB2 is grounded; The first end of the capacitor C COMP is connected with the output end of the error amplifier, the second end of the capacitor C COMP is connected with the first end of the resistor R COMP , the second end of the resistor R COMP is grounded, and the first end of the capacitor C COMP_P is grounded with the output end of the error amplifier, and the second end is grounded.
9. The interleaved stabilized wireless charging system according to claim 1 wherein the transmit coil and the receive coil are both LCC compensated, the resonant frequency of the coils is equal to the switching frequency of the switching tubes in the inverter circuit, the first and second voltage stabilizing circuits are in synchronous buck configuration, and the switching frequencies of the switching tubes in the first and second voltage stabilizing circuits are lower than the switching frequencies of the switching tubes in the inverter circuit to reduce switching losses.

Description

Staggered parallel voltage-stabilizing wireless charging system Technical Field The invention relates to the technical field of wireless charging, in particular to a staggered parallel voltage-stabilizing wireless charging system. Background With the continuous development of electronic technology, wireless charging technology is increasingly widely used. Compared with the traditional wired charging technology, the wireless charging technology does not need the wire connection of a power end and a load end, can realize the spaced transmission of energy, simultaneously avoids frequent plugging and unplugging, and has the advantages of safety, convenience, attractive appearance and the like. At the same time, wireless charging also faces challenges, such as the fact that the primary and secondary coil positions are not completely fixed, and the relative position changes can cause large fluctuations in the energy transferred by the coils, thus requiring a wider regulation range and a faster dynamic response output power regulation system. If the primary side power adjustment mode is adopted, the communication system between the primary side and the secondary side can increase the cost and the design difficulty of the system, and the response speed of the system can be influenced by the delay of signal transmission. Meanwhile, as the current of wireless charging is larger and larger, the current stress born by the switching device is also increased, the requirement on the output capacitance is also higher and higher, the reliability of the system is ensured, a large-current switching device is selected, the capacity of the output capacitance is increased, and the volume and the cost of the system are increased. Disclosure of Invention The invention aims to provide a staggered parallel voltage-stabilizing wireless charging system so as to solve the problems in the background technology. In order to solve the technical problems, the invention provides a staggered parallel voltage-stabilizing wireless charging system, which comprises a primary side and a secondary side; The primary side comprises a direct current power supply V IN, an inverter circuit, an inverter controller, primary side compensation and a transmitting coil, and the secondary side comprises a receiving coil, secondary side compensation, a rectifying circuit, a voltage stabilizing circuit I and a voltage stabilizing circuit II; The voltage of the direct current power supply V IN is converted into high-frequency alternating current through an inverter circuit; The high-frequency alternating current output by the inverter circuit is added to a primary side resonance circuit formed by primary side compensation and a transmitting coil, and the transmitting coil transmits energy to a receiving coil through magnetic coupling resonance; After the receiving coil receives energy from the transmitting coil, the receiving coil and the secondary side compensation form a secondary side resonance circuit, and the received alternating current is input into a rectification circuit; The rectification circuit adopts a non-control rectification structure to convert received high-frequency alternating current into direct current V D, the voltage stabilizing circuit I and the voltage stabilizing circuit II convert V D into set output voltage V OUT, the two voltage stabilizing circuits have the same structure and are synchronous buck-structure switch converters, and peak current mode control is adopted to facilitate current sharing control between the two circuits. In one embodiment, the inverter circuit comprises switching tubes Q1, Q2, Q3 and Q4, and gate ends of the switching tubes are connected to an inverter controller; The drain end of the switching tube Q1 and the drain end of the switching tube Q3 are both connected with the positive end of the direct current power supply V IN, and the source end of the switching tube Q2 and the source end of the switching tube Q4 are both connected with the negative end of the direct current power supply V IN; The source end of the switching tube Q1 is connected with the drain end of the switching tube Q2, and the source end of the switching tube Q3 is connected with the drain end of the switching tube Q4. In one embodiment, the primary compensation includes an inductor L P, a capacitor C P and a capacitor C1, where a first end of the inductor L P is connected to the source end of the switch Q1 and the drain end of the switch Q2 at the same time, a second end of the inductor L P is connected to the first end of the capacitor C1 and the first end of the capacitor C P at the same time, a second end of the capacitor C P is connected to the source end of the switch Q3 and the drain end of the switch Q4 at the same time, a second end of the capacitor C1 is connected to the first end of the transmitting coil, and a second end of the transmitting coil is connected to the second end of the capacitor C P. In one embodiment, the rectify