Wireless Charging System

Abstract

To provide a wireless charging system that improves stability during wireless charging.SOLUTION: A wireless charging system 10 includes a wireless power supply platform 100, a first device 200_1, and a second device 200_2. The wireless power supply platform 100 includes a coil LP that outputs wireless power supply power WP. The first device 200_1 includes a first power receiving circuit 210_1, a first power switch SW1, and a first control circuit 220_1. The second device 200_2 includes a second power receiving circuit 210_2, a second power switch SW2, and a second control circuit 220_2. The second control circuit communicates with the first control circuit to determine a cooperative switch state of the first power switch and the second power switch, and the cooperative switch state determines a first output voltage value VO1 generated by the first power receiving circuit on the basis of the wireless power supply power and a second output voltage value VO2 generated by the second power receiving circuit on the basis of the wireless power supply power.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a charging system, and more particularly to a wireless charging system. [Background technology]

[0002] Generally, in a wireless charging system, a wireless power supply platform can wirelessly charge a target device, such as an electronic device or a mobile vehicle, with a wireless charging function, thereby providing convenient charging.

[0003] A wireless charging platform may supply power to multiple target devices. It should be noted that the power supply specifications of the target devices may not be completely identical. The power supply specifications may include, for example, charging voltage and operating power. When the wireless charging platform supplies power to the target devices with different power supply specifications, the target devices may interfere with each other, significantly reducing the operational stability and charging stability of the target devices.

[0004] As can be seen from this, how to reduce mutual interference during charging of target devices is one of the focuses of research by those skilled in the art. Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention provides a wireless charging system that can improve the stability of wireless charging of a device to be charged. [Means for solving the problem]

[0006] A wireless charging system of the present invention includes a wireless power transfer platform, a first device, and a second device. The wireless power transfer platform provides wirelessly transferred power. The first device includes a first power receiving circuit, a first power switch, and a first control circuit. The first power switch is coupled to the first power receiving circuit. The first control circuit is coupled to the first power switch. The second device includes a second power receiving circuit, a second power switch, and a second control circuit. The second power switch is coupled to the second power receiving circuit. The second control circuit is coupled to the second power switch. The second control circuit communicates with the first control circuit to determine a coordinated switch state of the first power switch and the second power switch. The coordinated switch state determines a first output voltage value generated by the first power receiving circuit based on the wirelessly transferred power and a second output voltage value generated by the second power receiving circuit based on the wirelessly transferred power. [Effects of the Invention]

[0007] Based on the above, the second control circuit communicates with the first control circuit to determine cooperative switch states of the first power switch and the second power switch. The cooperative switch states determine a first output voltage value generated based on the wirelessly transmitted power of the first power receiving circuit and a second output voltage value generated based on the wirelessly transmitted power of the second power receiving circuit. In this way, based on the communication between the second control circuit and the first control circuit, both the first device and the second device can obtain output voltage values ​​that comply with the power supply specifications using the cooperative switch states.

[0008] In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following embodiments will be described in detail in conjunction with the drawings. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a wireless charging system illustrated in accordance with one embodiment of the present invention. [Figure 2] FIG. 1 is a circuit diagram of a wireless charging system illustrated in accordance with one embodiment of the present invention. [Figure 3] 3 is a schematic diagram of the converted power and output voltage values ​​in different coordinated switch states of the present invention; [Figure 4] FIG. 1 is a gain diagram illustrated in accordance with one embodiment of the present invention. [Figure 5] FIG. 10 is a gain diagram for a first coordinated switch state illustrated in accordance with one embodiment of the present invention. [Figure 6] FIG. 10 is a gain diagram for a second coordinated switch state illustrated in accordance with one embodiment of the present invention. [Figure 7] FIG. 1 is a communication diagram of an illustrated wireless charging system according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Some embodiments of the present invention will be described in detail below with reference to the drawings. Regarding the reference numerals of elements used in the following description, the same reference numerals appearing in different drawings are considered to be the same or similar elements. These embodiments are merely a part of the present invention and do not disclose all potential implementation modes of the present invention. More precisely, these embodiments are merely examples within the patentable scope of the present invention.

[0011] Referring to FIG. 1, FIG. 1 is a schematic diagram of a wireless charging system illustrated according to one embodiment of the present invention. In this embodiment, the wireless charging system 10 includes a wireless power supply platform 100 and devices 200_1 and 200_2. The wireless power supply platform 100 provides wirelessly supplied power WP. The devices 200_1 and 200_2 are, for example, electronic devices or mobile vehicles equipped with wireless charging capabilities. For example, the device 200_1 may be a portable electronic device, an electric vehicle (EV), or an automated guided vehicle (AGV) equipped with wireless charging capabilities, but the present invention is not limited thereto.

[0012] In this embodiment, the device 200_1 includes a power receiving circuit 210_1, a power switch SW1, and a control circuit 220_1. The power switch SW1 is coupled to the power receiving circuit 210_1. The control circuit 220_1 is coupled to the power switch SW1. The device 200_2 includes a power receiving circuit 210_2, a power switch SW2, and a control circuit 220_2. The power switch SW2 is coupled to the power receiving circuit 210_2. The control circuit 220_2 is coupled to the power switch SW2. The control circuit 220_2 communicates with the control circuit 220_1 to determine a cooperative switch state of the power switches SW1 and SW2. The cooperative switch state determines a first output voltage value VO1 generated based on the wirelessly supplied power WP of the power receiving circuit 210_1 and a second output voltage value VO2 generated based on the wirelessly supplied power WP of the second power receiving circuit 210_2.

[0013] For example, based on the power supply specifications of the device 200_1, the device 200_1 may operate or charge using output power having an output voltage value VO1. Based on the power supply specifications of the device 200_2, the device 200_2 may operate or charge using output power having an output voltage value VO2. The wireless power supply platform 100 provides wireless power WP to a field (not shown). When the devices 200_1 and 200_2 enter the field, the control circuit 220_2 communicates with the control circuit 220_1. Therefore, the control circuit 220_1 can know the power supply specifications of the device 220_2. The control circuit 220_2 can also know the power supply specifications of the device 220_1. The control circuit 220_1 may control the switch state of the power switch SW1. The control circuit 220_2 may control the switch state of the power switch SW2. When the devices 200_1 and 200_2 enter the field, the switch states of the power switches SW1 and SW2 affect the output voltage value VO1 generated by the power receiving circuit 210_1 and may also affect the output voltage value VO2 generated by the power receiving circuit 210_2.

[0014] It should be noted here that the control circuits 220_1 and 220_2 communicate to determine the cooperative switch states of the power switches SW1 and SW2. The cooperative switch states determine the output voltage value VO1 generated by the wireless charging power WP of the power receiving circuit 210_1 and also determine the output voltage value VO2 generated by the wireless charging power WP of the power receiving circuit 210_2. In this way, based on the communication between the control circuits 220_1 and 220_2, both of the devices 200_1 and 200_2 can obtain the output voltage values ​​VO1 and VO2 that comply with the power supply specifications using the cooperative switch states. Therefore, based on the communication between the control circuits 220_1 and 220_2, mutual interference during charging of the devices 200_1 and 200_2 can be reduced.

[0015] In this embodiment, the device 200_1 further includes a battery module BT1. The battery module BT1 is coupled to the power receiving circuit 210_1. Based on the power supply specifications of the device 200_1, the battery module BT1 stores power having an output voltage value VO1. In this embodiment, the battery module BT1 includes an aluminum ion battery. The aluminum ion battery has a high charge / discharge rate (C rate). Therefore, the battery module BT1 can achieve the advantage of rapid charging. In addition, the device 200_1 further drives a load element (e.g., a motor) using the output power having the output voltage value VO1.

[0016] Similar to the device 200_1, the device 200_2 further includes a battery module BT2. The battery module BT2 is coupled to the power receiving circuit 210_2. Based on the power supply specification of the device 200_2, the battery module BT2 stores power having an output voltage value VO2. In this embodiment, the battery module BT2 includes an aluminum ion battery. The aluminum ion battery has a high charge / discharge rate. Therefore, the battery module BT2 can achieve the advantage of rapid charging. In addition, the device 200_2 further drives a load element using the output power having the output voltage value VO2.

[0017] In this embodiment, the wireless power transfer platform 100 includes an inverter 110, a resonant circuit 120, and a coil LP. The inverter 110 receives input power PS and converts the input power PS into converted power PD. In this embodiment, the inverter 110 may be a full-bridge inverter circuit. The input power PS is a DC power supply. The converted power PD is an AC power supply. The resonant circuit 120 is coupled to the inverter 110. The resonant circuit 120 generates converted power PG by performing a resonant operation on the converted power PD. The coil LP is coupled to the resonant circuit 120. The coil LP receives the converted power PG and outputs wirelessly transferred power WP based on the converted power PG. In this embodiment, the wireless power transfer platform 100 transmits the wirelessly transferred power WP to the power receiving circuits 210_1 and 210_2 by magnetic field coupling.

[0018] In this embodiment, the power switches SW1 and SW2 may each be realized by a transistor switch that is well known to those skilled in the art.

[0019] Referring to FIG. 2, FIG. 2 is a circuit diagram of a wireless charging system illustrated according to one embodiment of the present invention. In this embodiment, the wireless charging system 20 includes a wireless power transfer platform 300 and devices 400_1 and 400_2. The wireless power transfer platform 300 includes an inverter 310, a resonant circuit 320, a control circuit 330, and a coil LP. The inverter 310 receives input power PS under the control of the control circuit 330, and converts the input power PS into converted power PD. The resonant circuit 320 is coupled to the inverter 310. The resonant circuit 320 resonates with the converted power PD to generate converted power PG. The coil LP is coupled to the resonant circuit 320. The coil LP outputs wirelessly-transmitted power WP based on the converted power PG.

[0020] Taking this embodiment as an example, the resonant circuit 320 includes an inductor LR and capacitors CR1 and CR2 (the present invention does not limit the circuit form of the resonant circuit 320). A first terminal of the inductor LR is coupled to a first output terminal of the inverter 310. A first terminal of the capacitor CR1 is coupled to a second terminal of the inductor LR. A second terminal of the capacitor CR1 is coupled to a first terminal of the coil LP. A first terminal of the capacitor CR2 is coupled to a second terminal of the inductor LR. A second terminal of the capacitor CR2 is coupled to the second terminal of the coil LP and the second output terminal of the inverter 310.

[0021] In this embodiment, the device 400_1 includes a power receiving circuit 410_1, a power switch SW1, and a control circuit 420_1. The power receiving circuit 410_1 includes a coil LS1, a resonant circuit 411_1, and a rectifier circuit 412_1. The resonant circuit 411_1 is coupled to the power switch SW1 and the coil LS1. The resonant circuit 411_1 receives the wirelessly powered power WP via the coil LS1 and amplifies the wirelessly powered power WP to generate converted power PC1. The rectifier circuit 412_1 is coupled to the resonant circuit 411_1. The rectifier circuit 412_1 rectifies the converted power PC1 to generate output power PO1 having an output voltage value VO1.

[0022] Taking this embodiment as an example, the resonant circuit 411_1 includes capacitors CS1_1 and CS2_1. A first terminal of the capacitor CS1_1 is coupled to a first terminal of the coil LS1. A second terminal of the capacitor CS1_1 is coupled to a first terminal of the power switch SW1. A first terminal of the capacitor CS2_1 is coupled to a second terminal of the capacitor CS1_1. A second terminal of the capacitor CS2_1 is coupled to a second terminal of the coil LS1 and a second terminal of the power switch SW1. A control terminal of the power switch SW1 is coupled to a control circuit 420_1. The control circuit 420_1 may use a switch signal SSW1 to control the open / closed state of the power switch SW1.

[0023] In this embodiment, when the power switch SW1 is turned off, the resonant circuit 411_1 and the coil LS1 perform a first resonant operation. More specifically, when the power switch SW1 is turned off, the capacitors CS1_1, CS2_1 and the coil LS1 perform a first resonant operation of the power receiving circuit 410_1.

[0024] On the other hand, when the power switch SW1 is conductive, the resonant circuit 411_1 and the coil LS1 perform the second resonant operation of the power receiving circuit 410_1. More specifically, when the power switch SW1 is conductive, the capacitor CS2_1 is bypassed. Therefore, the capacitor CS1_1 and the coil LS1 perform the second resonant operation of the power receiving circuit 410_1. Furthermore, during the second resonant operation of the power receiving circuit 410_1, the coil LS1 serves as a relay resonant coil. The coil LS1 can transmit induced power to other devices (including the device 400_2) in the same field through inductive coupling.

[0025] Note that whether the power switch SW1 is turned off or on determines the number of capacitors involved in the resonant operation of the power receiving circuit 410_1. During the first resonant operation of the power receiving circuit 410_1, two capacitors CS1_1 and CS2_1 are involved in the resonant operation. During the second resonant operation of the power receiving circuit 410_1, the capacitor CS1_1 is involved in the resonant operation. Therefore, the gain generated by the power receiving circuit 410_1 during the first resonant operation is larger than the gain generated by the power receiving circuit 410_1 during the second resonant operation.

[0026] In this embodiment, the device 400_2 includes a power receiving circuit 410_2, a power switch SW2, and a control circuit 420_2. The power receiving circuit 410_2 includes a coil LS2, a resonant circuit 411_2, and a rectifier circuit 412_2. The resonant circuit 411_2 is coupled to the power switch SW2 and the coil LS2. The resonant circuit 411_2 receives the wirelessly powered power WP via the coil LS2 and amplifies the wirelessly powered power WP to generate converted power PC2. The rectifier circuit 412_2 is coupled to the resonant circuit 411_2. The rectifier circuit 412_2 rectifies the converted power PC2 to generate output power PO2 having an output voltage value VO2.

[0027] Taking this embodiment as an example, the resonant circuit 411_2 includes capacitors CS1_2 and CS2_2. A first terminal of the capacitor CS1_2 is coupled to a first terminal of the coil LS2. A second terminal of the capacitor CS1_2 is coupled to a first terminal of the power switch SW2. A first terminal of the capacitor CS2_2 is coupled to a second terminal of the capacitor CS1_1. A second terminal of the capacitor CS2_2 is coupled to a second terminal of the coil LS2 and a second terminal of the power switch SW2. A control terminal of the power switch SW2 is coupled to a control circuit 420_2. The control circuit 420_2 may use a switch signal SSW2 to control the open / closed state of the power switch SW2.

[0028] In this embodiment, when the power switch SW2 is turned off, the resonant circuit 411_2 and the coil LS2 perform a first resonant operation. More specifically, when the power switch SW2 is turned off, the capacitors CS1_2, CS2_2 and the coil LS2 perform a first resonant operation of the power receiving circuit 410_2.

[0029] On the other hand, when the power switch SW2 is conductive, the resonant circuit 411_2 and the coil LS2 perform the second resonant operation of the power receiving circuit 410_2. More specifically, when the power switch SW2 is conductive, the capacitor CS2_2 is bypassed. Therefore, the capacitor CS1_2 and the coil LS2 perform the second resonant operation of the power receiving circuit 410_2. During the second resonant operation of the power receiving circuit 410_2, the coil LS2 serves as a relay resonant coil. The coil LS2 can transmit induced power to other devices (including the device 400_1) in the same field through inductive coupling.

[0030] The interruption or conduction of the power switch SW2 determines the number of capacitors involved in the resonant operation of the power receiving circuit 410_2. During the first resonant operation of the power receiving circuit 410_2, two capacitors CS1_2 and CS2_2 participate in the resonant operation. During the second resonant operation of the power receiving circuit 410_2, the capacitor CS1_2 participates in the resonant operation. Therefore, the gain generated by the power receiving circuit 410_2 during the first resonant operation is larger than the gain generated by the power receiving circuit 410_2 during the second resonant operation.

[0031] 2 and 3, which are schematic diagrams illustrating the conversion power and the output voltage in different cooperative switch states according to the present invention. In this embodiment, the output voltage V01 generated by the power receiving circuit 410_1 is the average voltage generated by the power receiving circuit 410_1 based on the wirelessly supplied power Wp per unit time. The output voltage V02 generated by the power receiving circuit 410_2 is the average voltage generated by the power receiving circuit 410_2 based on the wirelessly supplied power Wp per unit time.

[0032] Taking this embodiment as an example, in a unit time interval TD1, the duty cycle of the switch signal SSW1 is 30%. The duty cycle of the switch signal SSW2 is 70%. The power switch SW1 is turned on in response to the switch signal SSW1 having a first voltage value (e.g., a high voltage value) between time t0 and time t1. As a result, the power receiving circuit 410_1 performs a second resonant operation. The voltage peak value of the converted power PC1 generated by the power receiving circuit 410_1 in the second resonant operation is approximately equal to 0 volts (although the present invention is not limited to this). In addition, the coil LS1 is a relay resonant coil. The coil LS1 can transmit induced power to the device 400_2 through inductive coupling.

[0033] The power switch SW2 is turned off in response to the switch signal SSW2 having a second voltage value (e.g., a low voltage value) between time t0 and time t1. As a result, the power receiving circuit 410_2 performs the first resonant operation. At this time, the converted power PC2 has a maximum voltage peak value based on the fact that the power receiving circuit 410_2 has performed the first resonant operation and the relay resonance M1 of the coil LS1.

[0034] During unit time interval TD1, power switch SW2 is turned on in response to switch signal SSW2 having a first voltage value between time points 1 and 2. As a result, power receiving circuit 410_2 performs a second resonant operation. The voltage peak value of converted power PC2 generated by power receiving circuit 410_2 in the second resonant operation is approximately equal to 0 volts (although the present invention is not limited to this). Furthermore, coil LS2 is a relay resonant coil. Coil LS2 can transmit induced power to device 400_1 through inductive coupling.

[0035] The power switch SW1 is turned off in response to the switch signal SSW1 having the second voltage value between time t1 and time t2. As a result, the power receiving circuit 410_1 performs the first resonant operation. At this time, the converted power PC1 has a maximum voltage peak value based on the fact that the power receiving circuit 410_1 has performed the first resonant operation and the relay resonance M2 of the coil LS2.

[0036] The output voltage value VO1_1 is the average voltage value generated by the power receiving circuit 410_1 in the unit time interval TD1. The output voltage value VO2_1 is the average voltage value generated by the power receiving circuit 410_2 in the unit time interval TD1. In the unit time interval TD1, the output voltage value VO1_1 is higher than the output voltage value VO2_1.

[0037] In the unit time interval TD2, the duty cycle of the switch signal SSW1 is 50%. The duty cycle of the switch signal SSW2 is also 50%. The power switch SW1 is turned on in response to the switch signal SSW1 having a first voltage value between time points t2 and t3. As a result, the power receiving circuit 410_1 performs a second resonant operation. The voltage peak value of the converted power PC1 generated by the power receiving circuit 410_1 in the second resonant operation is approximately equal to 0 volts. Furthermore, the coil LS1 is a relay resonant coil. The coil LS1 can transmit induced power to the device 400_2 through inductive coupling.

[0038] The power switch SW2 is turned off in response to the switch signal SSW2 having the second voltage value between time points t2 and t3. As a result, the power receiving circuit 410_2 performs the first resonant operation. At this time, the converted power PC2 has a maximum voltage peak value due to the power receiving circuit 410_2 performing the first resonant operation and the relay resonance M1 of the coil LS1.

[0039] During unit time interval TD2, the power switch SW2 is turned on in response to the switch signal SSW2 having a first voltage value between time points t3 and t4. Therefore, the power receiving circuit 410_2 performs a second resonant operation. The voltage peak value of the converted power PC2 generated by the power receiving circuit 410_2 in the second resonant operation is approximately equal to 0 volts (although the present invention is not limited to this). Furthermore, the coil LS2 is a relay resonant coil. The coil LS2 can transmit induced power to the device 400_1 through inductive coupling.

[0040] Between times t3 and t4, the power switch SW1 is turned off in response to the switch signal SSW1 having the second voltage value. As a result, the power receiving circuit 410_1 performs the first resonant operation. At this time, the converted power PC1 has a maximum voltage peak value based on the power receiving circuit 410_1 performing the first resonant operation and the relay resonance M2 of the coil LS2.

[0041] The output voltage value VO1_2 is the average voltage value generated by the power receiving circuit 410_1 in the unit time interval TD2. The output voltage value VO2_2 is the average voltage value generated by the power receiving circuit 410_2 in the unit time interval TD2. It should be noted that the unit time intervals TD1 and TD2 and the output voltage values ​​VO1_1 and VO1_2 are not the same. The output voltage values ​​VO1_1 and VO1_2 are positively correlated with the length of time that the power switch SW1 is in the off state in the unit time intervals TD1 and TD2, and negatively correlated with the length of time that the power switch SW2 is in the off state in the unit time intervals TD1 and TD2. Similarly, the output voltage values ​​VO2_1 and VO2_2 are not the same. The output voltage values ​​VO2_1 and VO2_2 are positively correlated with the length of time that the power switch SW2 is in the off state in the unit time intervals TD1 and TD2, and negatively correlated with the length of time that the power switch SW1 is in the off state in the unit time intervals TD1 and TD2. As can be seen, the output voltage values ​​VO1_1, VO1_2, VO2_1, and VO2_2 may be determined by the duty cycles of the switch signals SSW1 and SSW2.

[0042] In unit time interval TD3, the duty cycle of switch signal SSW1 is 50%. The duty cycle of switch signal SSW2 is 40%. Therefore, unit time interval TD3 has a dead time interval. The time length of the dead time interval is 10% of the time length of unit time interval TD3. Power switch SW1 is conductive between time points t4 and t5. Therefore, the power receiving circuit 410_1 performs a second resonant operation. The voltage peak value of converted power PC1 generated by the power receiving circuit 410_1 in the second resonant operation is approximately equal to 0 volts. Furthermore, coil LS1 is configured as a relay resonant coil. Coil LS1 can transmit induced power to device 400_2 through inductive coupling.

[0043] The power switch SW2 is turned off between time points t4 and t5. Therefore, the power receiving circuit 410_2 performs the first resonant operation. At this time, the converted power PC2 has a maximum voltage peak value based on the fact that the power receiving circuit 410_2 has performed the first resonant operation and the relay resonance M1 of the coil LS1.

[0044] During the dead time period between time points t5 and t6, both switch signals SSW1 and SSW2 are cut off. As a result, the power receiving circuits 410_1 and 410_2 perform the first resonant operation. The voltage peak value of the converted power PC1 is approximately the same as the voltage peak value of the converted power PC2 (although the present invention is not limited to this). In other words, during the dead time period, the wirelessly transmitted power WP is evenly distributed to the power receiving circuits 410_1 and 410_2.

[0045] In unit time interval TD3, power switch SW2 is turned on between time points t6 and t7. Therefore, the power receiving circuit 410_2 performs a second resonant operation. The voltage peak value of converted power PC2 generated by the power receiving circuit 410_2 in the second resonant operation is approximately equal to 0 volts (although the present invention is not limited to this). Furthermore, coil LS2 is a relay resonant coil. Coil LS2 can transmit induced power to device 400_1 through inductive coupling.

[0046] The power switch SW1 is turned off between time points t6 and t7. Therefore, the power receiving circuit 410_1 performs the first resonant operation. At this time, the converted power PC1 has a maximum voltage peak value based on the fact that the power receiving circuit 410_1 has performed the first resonant operation and the relay resonance M2 of the coil LS2.

[0047] Compared to unit time interval TD2, unit time interval TD3 has a dead time interval. Therefore, the output voltage value VO1_3 is lower than the output voltage value VO1_2. Therefore, the output voltage value VO2_3 is higher than the output voltage value VO2_2. In other words, the time length of the dead time interval can determine the output voltage values ​​VO1_3 and VO2_3.

[0048] In unit time interval TD4, the duty cycle of switch signal SSW1 is 50%. The duty cycle of switch signal SSW2 is 20%. Therefore, unit time interval TD4 has a dead time interval. The time length of the dead time interval is 30% of the time length of unit time interval TD4. Power switch SW1 is conductive between time points t7 and t8. Therefore, the power receiving circuit 410_1 performs the second resonant operation. The voltage peak value of the converted power PC1 generated by the power receiving circuit 410_1 in the second resonant operation is approximately equal to 0 volts. Furthermore, coil LS1 is configured as a relay resonant coil. Coil LS1 can transmit induced power to device 400_2 through inductive coupling.

[0049] The power switch SW2 is turned off between time points t7 and t8. As a result, the power receiving circuit 410_2 performs the first resonant operation. At this time, the converted power PC2 has a maximum voltage peak value based on the fact that the power receiving circuit 410_2 has performed the first resonant operation and the relay resonance M1 of the coil LS1.

[0050] During the dead time period between time points t8 and t9, both switch signals SSW1 and SSW2 are cut off. Therefore, the power receiving circuits 410_1 and 410_2 perform the first resonant operation. The voltage peak value of the converted power PC1 is approximately the same as the voltage peak value of the converted power PC2 (although the present invention is not limited to this). In other words, during the dead time period, the wirelessly transmitted power WP is evenly distributed to the power receiving circuits 410_1 and 410_2.

[0051] In unit time interval TD4, power switch SW2 is turned on between time points t9 and t10. Therefore, the power receiving circuit 410_2 performs a second resonant operation. The voltage peak value of converted power PC2 generated by the power receiving circuit 410_2 in the second resonant operation is approximately equal to 0 volts (although the present invention is not limited to this). Furthermore, coil LS2 is a relay resonant coil. Coil LS2 can transmit induced power to device 400_1 through inductive coupling.

[0052] The power switch SW1 is turned off between time points t9 and t10. As a result, the power receiving circuit 410_1 performs the first resonant operation. At this time, the converted power PC1 has a maximum voltage peak value based on the fact that the power receiving circuit 410_1 has performed the first resonant operation and the relay resonance M2 of the coil LS2.

[0053] Compared to the unit time interval TD3, the unit time interval TD4 has a dead time interval. Therefore, the output voltage value VO1_4 is lower than the output voltage value VO1_3. Therefore, the output voltage value VO2_4 is higher than the output voltage value VO2_3.

[0054] In this embodiment, the switch signals SSW1 and SSW2 may each be a pulse-width modulation (PWM) signal, and the duty cycles of the switch signals SSW1 and SSW2 may be used to determine the output voltage values ​​VO1_1 to VO1_4 and VO2_1 to VO2_4.

[0055] Returning to the embodiment of FIG. 2, in this embodiment, the power receiving circuit 410_1 further includes a filter circuit 413_1. The filter circuit 413_1 is coupled to the rectifier circuit 412_1. The filter circuit 413_1 filters noise from the output power PO1. The filter circuit 413_1 may be implemented by a low-pass filter. For example, the filter circuit 413_1 includes an inductor LF1 and a capacitor CF1. The inductor LF1 is coupled between a first output terminal of the power receiving circuit 410_1 and a first terminal of the rectifier circuit 412_1. A first terminal of the capacitor CF1 is coupled to the first output terminal of the power receiving circuit 410_1. A second terminal of the capacitor CF1 is coupled to a second output terminal of the power receiving circuit 410_1 and a second terminal of the rectifier circuit 412_1. The power receiving circuit 410_2 further includes a filter circuit 413_2. The filter circuit 413_2 is coupled to the rectifier circuit 412_2. The filter circuit 413_2 filters noise from the output power PO2. The filter circuit 413_2 may be implemented by a low-pass filter. For example, the filter circuit 413_2 includes an inductor LF2 and a capacitor CF2. The inductor LF2 is coupled between a first output terminal of the power receiving circuit 410_2 and a first terminal of the rectifier circuit 412_2. A first terminal of the capacitor CF2 is coupled to the first output terminal of the power receiving circuit 410_2. A second terminal of the capacitor CF2 is coupled to a second output terminal of the power receiving circuit 410_2 and a second terminal of the rectifier circuit 412_2.

[0056] In some embodiments, a first terminal of the power switch SW1 is coupled to a first terminal of the capacitor CS1_1. A second terminal of the power switch SW1 is coupled to a second terminal of the capacitor CS1_1. When the power switch SW1 is turned on, the capacitor CS1_1 is bypassed. In some embodiments, a first terminal of the power switch SW2 is coupled to a first terminal of the capacitor CS1_2. A second terminal of the power switch SW2 is coupled to a second terminal of the capacitor CS1_2. When the power switch SW2 is turned on, the capacitor CS1_2 is bypassed.

[0057] In some embodiments, the first terminal of the power switch SW1 is coupled to the second terminal of the capacitor CS2_1. The second terminal of the power switch SW1 is coupled to the second terminal of the coil LS1. In some embodiments, the first terminal of the power switch SW2 is coupled to the second terminal of the capacitor CS2_2. The second terminal of the power switch SW2 is coupled to the second terminal of the coil LS2.

[0058] 2, 3, and 4, FIG. 4 is a gain diagram illustrated according to one embodiment of the present invention. FIG. 4 shows the gain AG1 under different load conditions of the device 400_1. The situation in FIG. 4 may be a situation where the device 400_1 is present in a field and the device 400_2 is not present in the field. In this embodiment, the load under load condition CD1 is heavier than the load under load condition CD2. The load under load condition CD2 is heavier than the load under load condition CD3. The load under load condition CD3 is heavier than the load under load condition CD4. Under load condition CD4, the gain at the resonant frequency FS of the device 400_1 is 23 times. The resonant frequency FS in this embodiment is, for example, 69 kHz (the present invention does not limit the resonant frequency FS).

[0059] 2, 3, and 5, FIG. 5 is a gain diagram for a first cooperative switching state illustrated in accordance with one embodiment of the present invention. FIG. 5 illustrates a gain AG1 of the device 400_1 under different load conditions and a gain AG2 of the device 400_2 under different load conditions. The first cooperative switching state may be a cooperative switching state during a dead time period of the devices 400_1 and 400_2. The dead time period may be between time t5 and time t6. The dead time period may be between time t8 and time t9. In this embodiment, the load under load condition CD1 is heavier than the load under load condition CD2. The load under load condition CD2 is heavier than the load under load condition CD3. The load under load condition CD3 is heavier than the load under load condition CD4. Under load condition CD4, the gain at the resonant frequency FS of the device 400_1 is 12 times.

[0060] 2, 3, and 6, FIG. 6 is a gain diagram for a second coordinated switch state illustrated according to one embodiment of the present invention. FIG. 6 illustrates the gain AG1 for different load conditions of the device 400_1. The second coordinated switch state may be a switch state in which the switch SW1 is turned off and the switch SW2 is turned on. In this embodiment, the load for the load condition CD1 is heavier than the load for the load condition CD2. The load for the load condition CD2 is heavier than the load for the load condition CD3. The load for the load condition CD3 is heavier than the load for the load condition CD4. Under the load condition CD4, the gain at the resonant frequency FS of the device 400_1 is 18 times.

[0061] As can be seen, the gains AG1, AG2 may be adjusted based on different coordinated switch states.

[0062] 2 and 7, which shows a communication diagram of a wireless charging system according to one embodiment of the present invention. In this embodiment, FIG. 7 shows control circuits 330, 420_1, and 420_2.

[0063] In this embodiment, the control circuit 420_1 includes a processing circuit 421_1 and a driving circuit 422_1. The processing circuit 421_1 and the control circuit 420_2 communicate wirelessly to generate a control signal SC1. The driving circuit 422_1 is coupled to the processing circuit 421_1 and a control terminal of the power switch SW1. The driving circuit 422_1 determines the switch state of the power switch SW1 in response to the control signal SC1.

[0064] The control circuit 420_1 further includes a feedback circuit 423_1. The feedback circuit 423_1 is coupled to the processing circuit 421_1 and the power receiving circuit 410_1. The feedback circuit 423_1 receives the output voltage value V01. The feedback circuit 423_1 determines whether the output voltage value V01 complies with the power supply specifications of the device 400_1. If the output voltage value V01 does not comply with the power supply specifications of the device 400_1, the feedback circuit 423_1 provides a feedback signal SF1 to the processing circuit 421_1. The processing circuit 421_1 adjusts the control signal SC1 based on the feedback signal SF1. Thus, the switch state of the power switch SW1 is correspondingly adjusted, thereby making the output voltage value V01 comply with the power supply specifications of the device 400_1. In some embodiments, the feedback circuit 423_1 determines whether the output voltage value V01 and the current value of the converted power PC1 comply with the power supply specifications of the device 400_1. If at least one of the output voltage value VO1 and the current value of the converted power PC1 does not comply with the power supply specification of the device 400_1, the feedback circuit 423_1 provides a feedback signal SF1 to the processing circuit 421_1.

[0065] In this embodiment, the control circuit 420_2 includes a processing circuit 421_2 and a driving circuit 422_2. The processing circuit 421_2 and the control circuit 420_1 communicate wirelessly to generate a control signal SC2. The driving circuit 422_2 is coupled to the processing circuit 421_2 and a control terminal of the power switch SW2. The driving circuit 422_2 determines the switch state of the power switch SW2 in response to the control signal SC2.

[0066] The control circuit 420_2 further includes a feedback circuit 423_2. The feedback circuit 423_2 is coupled to the processing circuit 421_2 and the power receiving circuit 410_2. The feedback circuit 423_2 receives the output voltage value V02. The feedback circuit 423_2 determines whether the output voltage value V02 complies with the power supply specifications of the device 400_2. If the output voltage value V02 does not comply with the power supply specifications of the device 400_2, the feedback circuit 423_2 provides a feedback signal SF2 to the processing circuit 421_2. The processing circuit 421_2 adjusts the control signal SC2 based on the feedback signal SF2. Thus, the switch state of the power switch SW2 is correspondingly adjusted, thereby making the output voltage value V02 comply with the power supply specifications of the device 400_2. In some embodiments, the feedback circuit 423_2 determines whether the output voltage value V02 and the current value of the converted power PC2 comply with the power supply specifications of the device 400_2. If at least one of the output voltage value VO2 and the current value of the converted power PC2 does not comply with the power supply specification of the device 400_2, the feedback circuit 423_2 provides a feedback signal SF2 to the processing circuit 421_2.

[0067] In this embodiment, the control circuit 330 includes a processing circuit 331, a driving circuit 332, and a feedback circuit 333. The processing circuit 331 and the processing circuits 421_1 and 421_2 perform wireless communication to generate a control signal SC0. The driving circuit 332 is coupled to the processing circuit 331 and the inverter 310. The driving circuit 332 controls the inverter 310 by providing operation signals ST1 to ST4 in response to the control signal SC0. Thus, the wireless power supply platform 300 may provide corresponding wireless power supply power WP based on the wireless communication between the processing circuit 331 and the processing circuits 421_1 and 421_2.

[0068] The feedback circuit 333 is coupled to the processing circuit 331. The feedback circuit 423_2 receives at least one of the input power PS and the converted power PD. The feedback circuit 423_2 provides a feedback signal SF0 based on at least one of the input power PS and the converted power PD. For example, the feedback circuit 423_2 provides the feedback signal SF0 based on at least one of the voltage value of the input power PS or the voltage value of the converted power PD. The processing circuit 331 adjusts the control signal SC0 based on the feedback signal SF0. ​​As a result, the converted power PD can be stabilized.

[0069] In this embodiment, the processing circuits 331, 421_1, and 421_2 are, for example, a central processing unit (CPU) or other programmable general-purpose or special-purpose microprocessor, a digital signal processor (DSP), a programmable controller, an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or other similar device, or a combination of devices capable of loading and executing a computer program. The processing circuits 331, 421_1, and 421_2 may communicate using any wireless communication protocol. For example, the processing circuits 331, 421_1, and 421_2 may communicate using the Bluetooth® communication protocol (although the present invention is not limited thereto).

[0070] To summarize the above, the first device includes a first power receiving circuit, a first power switch, and a first control circuit. The second device includes a second power receiving circuit, a second power switch, and a second control circuit. The first control circuit and the second control circuit communicate to determine cooperative switch states of the first power switch and the second power switch. The cooperative switch states determine a first output voltage value generated by the first power receiving circuit based on the wirelessly transmitted power and a second output voltage value generated by the second power receiving circuit based on the wirelessly transmitted power. In this way, based on the communication between the second control circuit and the first control circuit, both the first device and the second device can obtain output voltage values ​​that comply with the power supply specifications using the cooperative switch states.

[0071] Although the present invention has been disclosed in the above embodiments, they are not used to limit the present application, and it is obvious that a person skilled in the art can make some modifications and changes without departing from the spirit and scope of the present invention, and therefore the protection scope of the present invention is subject to that defined by the appended claims. [Industrial Applicability]

[0072] The present invention provides a wireless charging system, which can improve the stability of wireless charging of a device to be charged. [Explanation of symbols]

[0073] 10, 20: Wireless charging system 100, 300: Wireless power supply platform 110, 310: Inverter 120, 320: Resonant circuit 200_1, 200_2, 400_1, 400_2: Equipment 210_1, 210_2, 410_1, 410_2: Receiving circuits 220_1, 220_2, 420_1, 420_2: Control circuit 330: Control circuit 331, 421_1, 421_2: Processing circuit 332, 422_1, 422_2: Drive circuit 333, 423_1, 423_2: Feedback circuit 411_1, 411_2: Resonant circuit 412_1, 411_2: Rectifier circuit 413_1, 413_2: Filter circuit AG1, AG2: Gain BT1, BT2: Battery modules CF1, CF2, CR1, CR2, CS1_1, CS2_1, CS1_2, CS2_2: Capacitors CD1, CD2, CD3, CD4: Load conditions LP, LS1, LS2: Coil LF1, LF2, LR: inductors FS: Resonance frequency M1, M2: Relay resonance PC1, PC2, PD: Conversion power PO1, PO2: Output power PS: Input power SC0, SC1, SC2: Control signals SF0, SF1, SF2: Feedback signals ST1~ST4: Operation signal SSW1, SSW2: Switch signal SW1, SW2: Power switches t0~t10: time TD1, TD2, TD3, TD4: unit time interval VO1, VO1_1 to VO1_4, VO2, VO2_1 to VO2_4: Output voltage value WP: Wireless power supply

Claims

1. a wireless power platform configured to provide wirelessly-powered power; a first power receiving circuit including a coil; a first power switch coupled to the first power receiving circuit; a first control circuit coupled to the first power switch; Including, a first device; and a second power receiving circuit; a second power switch coupled to the second power receiving circuit; a second control circuit coupled to the second power switch and configured to communicate with the first control circuit to determine a coordinated switch state of the first power switch and the second power switch; Including, A second device Including, the cooperative switch state determines a first output voltage value that the first power receiving circuit generates based on the wirelessly supplied power and a second output voltage value that the second power receiving circuit generates based on the wirelessly supplied power; In the field, when the first power switch is turned on, the coil acts as a relay resonant coil, and transmits induced power to a second device in the field through inductive coupling. Wireless charging system.

2. the wireless power platform provides wireless power to the field; When the first device and the second device enter the field, the second control circuit communicates with the first control circuit. The wireless charging system of claim 1 .

3. the first output voltage value is an average voltage value generated by the first power receiving circuit based on the wirelessly supplied power during a unit time period, the second output voltage value is an average voltage value generated by the second power receiving circuit based on the wirelessly supplied power during the unit time period; The wireless charging system of claim 1 .

4. the first output voltage value is positively correlated with a time length during which the first power switch is in an off state in the unit time section; the first output voltage value is negatively correlated with the length of time that the second power switch is in the cut-off state within the unit time interval; The wireless charging system according to claim 3 .

5. the second output voltage value is positively correlated with a time length during which the second power switch is in an off state in the unit time section; the second output voltage value is negatively correlated with the length of time that the first power switch is in the cut-off state within the unit time interval; The wireless charging system according to claim 3 .

6. The first power receiving circuit is a resonant circuit coupled to the first power switch and the coil, configured to receive the wirelessly-powered power via the coil and amplify the wirelessly-powered power to generate converted power; a rectifier circuit coupled to the resonant circuit and configured to rectify the converted power to generate output power having the first output voltage value; further comprising: The wireless charging system of claim 1 .

7. The first power receiving circuit is a battery module coupled to the first power receiving circuit and configured to store the output power; Further comprising: The wireless charging system of claim 6 .

8. the battery module includes aluminum ion batteries; The wireless charging system of claim 7.

9. When the first power switch is turned off, the resonant circuit and the coil perform a first resonant operation; When the first power switch is turned on, the resonant circuit and the coil perform a second resonant operation. The wireless charging system of claim 6 .

10. The resonant circuit comprises: A first capacitor; A second capacitor Including, a first terminal of the first capacitor coupled to a first terminal of the coil, and a second terminal of the first capacitor coupled to a first terminal of the first power switch; a first terminal of the second capacitor coupled to a second terminal of the first capacitor, and a second terminal of the second capacitor coupled to a second terminal of the coil and a second terminal of the first power switch; The wireless charging system of claim 6 .

11. when the first power switch is turned off, the first capacitor, the second capacitor, and the coil perform a first resonance operation; When the first power switch is turned on, the first capacitor and the coil perform a second resonant operation; a gain generated by the first power receiving circuit in the first resonant operation is greater than a gain generated by the first power receiving circuit in the second resonant operation; The wireless charging system of claim 10.

12. The first control circuit a processing circuit configured to wirelessly communicate with the second control circuit to generate a control signal; a driver circuit coupled to the processing circuit and to a control terminal of the first power switch, the driver circuit configured to determine a switch state of the first power switch in response to the control signal; Including, The wireless charging system of claim 1 .

13. The first control circuit a feedback circuit coupled to the processing circuit and the first power receiving circuit and configured to determine whether the first output voltage value complies with a power supply specification of the first device; Further comprising: the feedback circuit provides a feedback signal to the processing circuit when the first output voltage value does not comply with a power supply specification of the first device; the processing circuitry adjusts the control signal in response to the feedback signal. The wireless charging system of claim 12.

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