TWI846562B - Wireless charging control method and wireless charging system employing the same - Google Patents

Abstract

The present disclosure provides a wireless charging control method and a wireless charging system employing the same. The wireless charging control method is applicable for the wireless charging system including transmitter and receiver module and includes steps of: (a) when an input power is greater than a threshold power or an element temperature is greater than a threshold temperature, determining a target output power according to the input power or the element temperature by the transmitter module; (b) modulating an information about the target output power into an input power; (c) receiving and sampling the input power and demodulating the information about the target output power by the receiver module; (d) converting the input power into the target output power according to the information about the target output power by the receiver module.

Description

Wireless charging control method and applicable wireless charging system

This case is about a charging control method and a charging system applicable thereto, in particular, a wireless charging control method and a wireless charging system applicable thereto.

In wireless power transmission, when the distance between the transmitting coil and the receiving coil increases, the magnetic leakage also increases. At this time, the input power needs to increase significantly to maintain the same output power. Therefore, when the distance between the transmitting coil and the receiving coil increases to a certain extent, foreign object detection (FOD) may be activated due to excessive power loss, or low voltage protection may be activated due to too low voltage on the receiving side, or over-temperature protection may be activated due to too high temperature of the components on the transmitting side. The foreign object detection, low voltage protection and over-temperature protection may cause intermittent power transmission, thereby affecting the stability of wireless power transmission.

Therefore, it is an urgent need to invent a wireless charging control method and a wireless charging system applicable thereto that can improve the above-mentioned existing technologies.

The purpose of this case is to provide a wireless charging control method and a wireless charging system applicable thereto, which controls the transmitting side circuit to operate in a special adjustment mode when the input power or component temperature of the transmitting side is too high, and the receiving side can know that the transmitting side circuit operates in the adjustment mode by sampling the received power, and correspondingly reduce the output power, thereby reducing the input power. In this way, when the distance between the transmitting side and the receiving side increases, the input power can be prevented from excessively increasing and triggering the protection function and interrupting the power transmission, effectively improving the stability of wireless power transmission.

To achieve the above-mentioned purpose, the present invention provides a wireless charging control method for a wireless charging system including a transmitting module and a receiving module, comprising the steps of: (a) determining the target output power according to the input power or the component temperature through the transmitting module when the input power is greater than the power threshold or the component temperature is greater than the temperature threshold; (b) modulating the information about the target output power to the input electric energy through the transmitting module; (c) receiving and sampling the input electric energy through the receiving module to demodulate the information about the target output power; and (d) converting the input electric energy into the target output power according to the information about the target output power through the receiving module.

To achieve the above purpose, the present invention further provides a wireless charging system, including a transmitting module and a receiving module. The transmitting module is configured to convert input power into input electrical energy and then transmit it. The receiving module is configured to receive input electrical energy and convert the input electrical energy into output electrical energy to the load. The transmitting module and the receiving module are configured to execute the wireless charging control method of the present invention.

1: Wireless charging system

10: Transmitter module

20: Receiving module

30: Transmitter controller

40: Receiving controller

2: Load

PWM: driving signal

Vin: Input voltage

Iin: input current

Temp: Component temperature

11: Driving circuit

12: Switching circuit

13: Transmitter coil

C1, C2, C3, C4: capacitors

21: Receiving coil

22: Rectifier circuit

23: Step-down circuit

24: Communication circuit

31: First launch control unit

32: Second launch control unit

T: Charging cycle

Ta: The length of time between two interruptions

Ts: Duration of the switching cycle of the driving signal

S1, S2, S3, S4: switches

111: First drive

112: Second drive

D1, D2: diodes

S5, S6, S7, S8: switch

C5, C6: capacitors

L: Inductance

41: First receiving control unit

42: Second receiving control unit

43: Step-down control unit

Vo: output voltage

Io: output current

Pin: Input power

P_th: power threshold value

T_th: temperature threshold value

P_restore: restore power

T_restore: Restore temperature

S71, S72, S73, S74, S75, S76, S77, S78: Steps

S81, S82, S83, S84, S85, S86: Steps

S91, S92, S93, S94, S95: Steps

C7, C8: capacitors

S9, S10: switch

Figure 1 is a functional block diagram of a wireless charging system according to an embodiment of the present invention.

Figures 2 and 3 are functional block diagrams of a transmitter controller and a driver circuit according to another embodiment of the present invention.

Figure 4 is a waveform diagram of the interrupted drive signal according to the embodiment of this case.

Figure 5 is a waveform diagram of an interrupted drive signal according to multiple embodiments of the present invention.

Figure 6A illustrates an implementation of the transmitting module and transmitting controller of Figure 1.

Figure 6B illustrates an implementation of the receiving module and receiving controller of Figure 1.

Figure 7 is a schematic diagram of the process of the wireless charging method according to the embodiment of this case.

Figure 8 is a flowchart of a wireless charging control method for a transmitting module according to an embodiment of the present invention.

Figure 9 is a flowchart of a wireless charging control method for a receiving module according to an embodiment of the present invention.

Some typical embodiments that embody the features and advantages of this case will be described in detail in the following description. It should be understood that this case can have various variations in different forms, all of which do not deviate from the scope of this case.

FIG. 1 is a functional block diagram of a wireless charging system according to an embodiment of the present invention. As shown in FIG. 1, the wireless charging system 1 includes a transmitting module 10 and a receiving module 20, wherein the transmitting module 10 is located on the transmitting side of the wireless charging system 1, and the receiving module 20 is located on the receiving side of the wireless charging system 1. The transmitting module 10 receives input power, and converts the input power into input electric energy and then transmits it. The receiving module 20 is electromagnetically coupled with the transmitting module 10 for wireless power transmission, wherein the receiving module 20 receives the input electric energy transmitted by the transmitting module 10 via wireless power transmission, and converts the received input electric energy into output electric energy, and can provide the output electric energy to the load 2. The transmitting module 10 includes a transmitting controller 30, which is configured to provide a driving signal PWM to the transmitting module 10 to control the transmitting module 10 to operate in a normal mode, wherein the driving signal PWM has a switching cycle. The receiving module 20 includes a receiving controller 40, which is configured to control the operation of the receiving module 20.

During the operation of the wireless charging system 1, the transmitting controller 30 samples the input power (e.g., by sampling the input voltage Vin and the input current Iin) and senses the component temperature Temp in the transmitting module 10. When the input power is greater than the power threshold or the component temperature Temp is greater than the temperature threshold (i.e., the input power or the component temperature Temp is too high), the transmitting controller 30 switches the transmitting module 10 to the regulating mode. In the regulating mode, the transmitting controller 30 controls the transmitting module 10 to interrupt the driving signal PWM a specific number of times in a charging cycle, wherein the specific number of interruptions of the driving signal PWM depends on the size of the input power. The receiving controller 40 samples the input power received by the receiving module 20 to learn the specific number of times the transmitting module 10 interrupts the driving signal PWM during the charging cycle, and reduces the output power of the output power according to the specific number of times. When the output power is reduced, the input power received by the transmitting module 10 can be reduced accordingly.

The relationship between the specific number of times and the reduction range of the output power can be determined according to actual needs. For example, when the specific number of times the transmitting module 10 interrupts the driving signal PWM during the charging cycle is n, the receiving controller 40 reduces the output power to (100-n*10)% of the rated power, where n is a positive integer less than ten. In addition, the aforementioned charging cycle is pre-set in the transmitting controller 30 and the receiving controller 40, and can be adjusted according to actual needs.

In addition, it should be noted that the duration of each interruption of the drive signal PWM by the transmitting module 10 (e.g., a switching cycle of the drive signal PWM) is much shorter than the duration of the charging cycle, so the interruption of the drive signal PWM does not actually affect the wireless power transmission between the transmitting module 10 and the receiving module 20. In other words, in the adjustment mode, the interruption of the drive signal PWM does not affect the continuity and stability of the wireless power transmission.

As can be seen from the above, when the distance between the transmitting module 10 and the receiving module 20 increases, the receiving module 20 can immediately reduce the output power and reduce the input power accordingly, thereby avoiding the protection function being triggered and the power transmission being interrupted due to excessive increase in input power, effectively improving the stability of wireless power transmission.

Furthermore, after the output power is reduced, when the input power is lower than the recovery power and the component temperature Temp is lower than the recovery temperature (which means that the protection function will not be triggered), the transmitting controller 30 controls the transmitting module 10 to resume operation in normal mode. At this time, the receiving controller 40 learns that the transmitting module 10 operates in normal mode to generate normal input power by sampling AC power, and correspondingly increases the output power (for example, to the rated power). The recovery power can be, for example, but not limited to, 80% of the reference power, and the recovery temperature can be, for example, but not limited to, 80% of the reference temperature.

In addition, in some embodiments, when the input power is not lower than the recovery power and/or the component temperature Temp is not lower than the recovery temperature (i.e., when at least one of the conditions is met), the transmitting module 10 still generates input electrical energy corresponding to the target output power, and the receiving module 20 receives and converts the input electrical energy into the target output power.

In the embodiment shown in FIG. 1 , the transmitting module 10 further includes a driving circuit 11, a switching circuit 12, a transmitting coil 13, a first capacitor C1, and a second capacitor C2. The driving circuit 11 is electrically connected to the transmitting controller 30, and the switching circuit 12 is electrically connected to the driving circuit 11, wherein the driving circuit 11 and the switching circuit 12 are configured to convert input power into input electrical energy according to the driving signal. In the adjustment mode, when the driving signal PWM is interrupted, the switches of the switching circuit 12 are all in the off state. The transmitting coil 13 is coupled to the switching circuit 12 and is configured to transmit the input electrical energy. The first capacitor C1 is connected between the switching circuit 12 and the transmitting coil 13 and is configured to match the transmitting coil 13. The second capacitor C2 is connected between the switch circuit 12 and the transmitting coil 13 and is configured to match the transmitting coil 13.

The receiving module 20 further includes a receiving coil 21, a rectifier circuit 22, a step-down circuit 23, a communication circuit 24, a third capacitor C3 and a fourth capacitor C4. The receiving coil 21 is configured to receive input power. The rectifier circuit 22 is coupled to the receiving coil 21, and the step-down circuit 23 is electrically connected to the rectifier circuit 22, wherein the rectifier circuit 22 and the step-down circuit 23 are configured to convert the input power into output power, and perform rectification and step-down in the conversion process respectively. The communication circuit 24 is electrically connected to the receiving coil 21, and is configured to reflect the operating status of the receiving module 20 to the transmitting module 10. The third capacitor C3 is electrically connected between the receiving coil 21 and the rectifier circuit 22, and is configured to match the receiving coil 21. The fourth capacitor C4 is electrically connected between the receiving coil 21 and the rectifier circuit 22 and is configured to match the receiving coil 21.

In addition, the transmitting controller 30 can interrupt the driving signal PWM in different ways. The following examples illustrate several possible ways.

In the embodiment shown in FIG. 1, the transmitting controller 30 directly interrupts the generated driving signal PWM.

In the embodiment shown in FIG. 2, the transmitting controller 30 provides the driving signal PWM and the enable signal to the driving circuit 11 through different ports, so as to interrupt the driving signal PWM using the enable signal. For example, when the enable signal is at a high level, the driving signal PWM is interrupted, and the driving circuit 11 controls the switch in the switch circuit 12 to be in the off state, so that the transmitting module 10 is interrupted; and when the enable signal is at a low level, the driving circuit 11 drives the switch circuit 12 according to the driving signal PWM.

In the embodiment shown in FIG. 3, the transmitting controller 30 includes a first transmitting control unit 31 and a second transmitting control unit 32, wherein the first transmitting control unit 31 and the second transmitting control unit 32 respectively provide a driving signal PWM and an enable signal to the driving circuit 11, so as to interrupt the driving signal PWM using the enable signal. In one embodiment, the first transmitting control unit 31 and the second transmitting control unit 32 are not integrated into one transmitting controller 30; specifically, the second transmitting control unit 32 is an external controller of the existing wireless charging control system, which is configured to detect power and temperature and interrupt the driving signal PWM, so as to add a new adjustment mode in the existing wireless control charging system.

FIG. 4 is a waveform diagram of the interrupted drive signal PWM according to the embodiment of the present case. The transmitting controller 30 of FIG. 1 can generate the drive signal PWM as shown in FIG. 4, wherein T indicates the duration of the charging cycle, and Ta indicates the interval between two interruptions. Specifically, the transmitting controller 30 determines the number of interruptions according to the input power or the component temperature Temp, and then interrupts the drive signal PWM once in the (i*a)th switching cycle to modulate the information about the target output power in the output power; wherein a is the number of switching cycles between two interruptions, 0≦i≦(n-1), i*a is less than or equal to the charging cycle T, n is the number of interruptions, and a, i, and n are positive integers. In this implementation, the number of interruptions n is 3, the number of switching cycles a between two interruptions is 3, and the charging cycle T is equal to 30 switching cycles, so the target output power is (100-3*10)%=70% of the rated power. In this way, the transmitting controller 30 can adjust the information about the target output power to output electrical energy.

Next, the receiving controller 40 of FIG. 1 (or the first receiving control unit 41 of FIG. 6B ) can capture the falling edge of a switching cycle to the rising edge of the next switching cycle to sample the drive signal PWM (i.e., output power). When the receiving controller 40 first detects that the time difference between the falling edge and the rising edge is greater than half a switching cycle, the charging cycle T is accumulated through the first counter, and the number of interruptions is accumulated through the second counter. When the charging cycle T ends, the receiving controller 40 reads the number of interruptions accumulated by the second counter; wherein when the charging cycle T ends, the first counter and the second counter are reset; wherein the number of interruptions is information about the target output power. In this way, the receiving module 20 can demodulate the information about the target output power.

FIG. 5 is a waveform diagram of a drive signal that has been interrupted according to various embodiments of the present invention. In FIG. 5, Ts is used to indicate the duration of the switching cycle of the drive signal PWM, a solid line indicates the sampling signal when the transmitting module 10 operates in the adjustment mode, a dotted line indicates the sampling signal when the transmitting module 10 operates in the normal mode for comparison, and a shaded area indicates the interval in which the transmitting module 10 interrupts operation. As shown in FIG. 5, regardless of the time point when the transmitting module 10 interrupts operation, the receiving controller 40 can determine whether the drive signal PWM is interrupted based on the time from the falling edge of a cycle to the rising edge of the next cycle in the sampling signal. After each charging cycle T, the receiving controller 40 can count the number of interruptions of the driving signal PWM within the charging cycle T.

FIG. 6A illustrates an embodiment of the transmitting module 10 and the transmitting controller 30 of FIG. 1. As shown in FIG. 6A, the switch circuit 12 is a full-bridge switch circuit, including switches S1, S2, S3 and S4, wherein switch S1 is connected in series with switch S2, switch S3 is connected in series with switch S4, and the bridge arm formed by switches S1 and S2 is connected in parallel to the bridge arm formed by switches S3 and S4. The common connection point between switches S1 and S2 is connected to capacitor C1, and the common connection point between switches S3 and S4 is connected to capacitor C2. The driving circuit 11 includes a first driver 111 and a second driver 112. The first driver 111 receives a driving signal PWM and an enable signal from the transmitting controller 30, and controls the operation of switches S1 and S2 accordingly. The second driver 112 receives the driving signal PWM and the enable signal from the self-transmitting controller 30, and controls the operation of the switches S3 and S4 accordingly.

FIG. 6B illustrates an implementation of the receiving module 20 and the receiving controller 40 of FIG. 1. As shown in FIG. 6B, the rectifier circuit 22 includes a diode D1, a switch S5, a diode D2, a switch S6, and a capacitor C5, wherein the diode D1 is connected in series with the switch S5, the diode D2 is connected in series with the switch S6, and the bridge arm formed by the diode D1 and the switch S5, the bridge arm formed by the diode D2 and the switch S6, and the capacitor C5 are connected in parallel with each other. The step-down circuit 23 includes a switch S7, a switch S8, an inductor L and a capacitor C6, wherein the two ends of the switch S7 are electrically connected to the first end of the capacitor C5 and the first end of the switch S8, respectively, the two ends of the inductor L are electrically connected to the first end of the switch S8 and the first end of the capacitor C6, respectively, and the second end of the switch S8 is electrically connected to the second end of the capacitor C5 and the second end of the capacitor C6. The communication circuit 24 includes a capacitor C7, a switch S9, a capacitor C8 and a switch S10, wherein the first end of the capacitor C7 is electrically connected between the receiving coil 21 and the capacitor C3, the second end of the capacitor C7 is electrically connected to the first end of the switch S9, the first end of the capacitor C8 is electrically connected between the receiving coil 21 and the capacitor C4, the second end of the capacitor C8 is electrically connected to the first end of the switch S10, and the second end of the switch S9 is electrically connected to the second end of the switch S10.

The receiving controller 40 of the receiving module 20 includes a first receiving control unit 41, a second receiving control unit 42 and a step-down control unit 43. The first receiving control unit 41 is electrically connected to the step-down circuit 23 and the receiving coil 21, and the step-down control unit 43 is electrically connected to the step-down circuit 23 and the first receiving control unit 41, and is configured to control the operation of the step-down circuit 23. The first receiving control unit 41 samples the output voltage Vo and the output current Io to provide a control signal for the step-down control unit 43 to control the operation of the step-down circuit 23. In addition, the first receiving control unit 41 also samples the input power received by the receiving module 20, so as to know the number of interruptions of the driving signal PWM according to the input power after the transmitting module 10 switches to the adjustment mode. According to the number of interruptions, the first receiving control unit 41 provides a corresponding control signal to the buck control unit 43, so that the buck control unit 43 controls the buck circuit 23 to reduce the output power. Furthermore, the first receiving control unit 41 can also communicate with the load 2 to receive the working status of the load 2 and adjust the operation of the receiving module 20 accordingly. The second receiving control unit 42 is electrically connected to the rectifier circuit 22 and the communication circuit 24, and is configured to control the operation of the rectifier circuit 22 and the communication circuit 24.

FIG. 7 is a schematic diagram of the process of the wireless charging method according to the embodiment of the present case. The wireless charging method of FIG. 7 is applicable to the wireless charging system 1 of FIG. 1 and includes the following steps.

Step S71: The transmitting module 10 and the receiving module 20 operate in normal mode.

Step S72: Sample input power and sensing element temperature Temp through the transmitting module 10.

Step S73: Through the transmitting module 10, determine whether the input power Pin is greater than the power threshold value P_th or the component temperature Temp is greater than the temperature threshold value T_th. If so, proceed to step S74; if not, proceed to step S78.

Step S74: The information about the target output power is modulated in the input power through the transmitting module 10. In step S74, the transmitting module 10 switches to the adjustment mode, and in the adjustment mode, the transmitting module 10 is controlled to interrupt the driving signal PWM a specific number of times within the charging cycle T, wherein the specific number of times depends on the size of the input power Pin.

Step S75: Generate input power corresponding to the target output power through the transmitting module 10. It should be noted that if the transmitting module 10 and the receiving module 20 are both in normal mode, the target output power is equal to the rated power.

Step S76: Receive and sample input power through the receiving module 20 to demodulate information about the target output power.

Step S77: The received input power is converted into the target output power through the receiving module 20 according to the information about the target output power. In the present embodiment, the receiving module 20 learns the specific number of interruptions of the driving signal PWM by sampling the input power, and reduces the power of the input power to the target output power according to the number of interruptions. After executing step S77, step S72 will be performed again to continuously detect the input power Pin and the component temperature Temp.

Step S78: Through the transmitting module 10, determine whether the input power Pin is less than the recovery power P_restore and the component temperature Temp is less than the recovery temperature T_restore. If step S78 is judged as yes, then return to step S71, where the transmitting module 10 returns to the normal mode and the receiving module 20 knows that the transmitting module 10 operates in the normal mode by sampling the input power. If the judgment step S78 is no, proceed to step S75.

In one embodiment, step S74 includes: determining the number of interruptions according to the input power Pin or the component temperature Temp; and interrupting the drive signal PWM once in the (i*a)th switching cycle to modulate the information about the target output power in the input power; where a is the number of intervals, 0≦i≦(n-1), i*a is less than or equal to the charging cycle T, n is the number of interruptions, and a, i, and n are positive integers. In this way, the transmitting module 10 can modulate the information about the target output power in the input power.

In one embodiment, step S76 includes: capturing the falling edge of a switching cycle to the rising edge of the next switching cycle to sample the input power; when the time difference between the falling edge and the rising edge is detected for the first time to be greater than half a switching cycle, starting to accumulate the charging cycle T through the first counter, and starting to accumulate the number of interruptions through the second counter; and when the charging cycle T ends, reading the number of interruptions accumulated by the second counter; wherein when the charging cycle T ends, the first counter and the second counter are reset; wherein the number of interruptions is the information of the target output power. In this way, the receiving module 20 can demodulate the information about the target output power.

Through the wireless charging method of Figure 7, the transmitting module 10 can actively reduce the power of the input electric energy, and will not immediately activate foreign object detection, low voltage protection and over-temperature protection, which can improve the intermittent power transmission situation.

FIG. 8 is a flow chart of a wireless charging control method for a transmitting module according to an embodiment of the present invention. The transmitting controller 30 of FIG. 1 and the second transmitting control unit 32 of FIG. 3 may have a built-in memory, and the wireless charging control method of FIG. 8 may be compiled into a program code and stored in the memory, and includes the following steps.

Step S81: Sample input power Pin and sensing element temperature Temp.

Step S82: Determine whether the input power Pin is greater than the power threshold value P_th or the component temperature Temp is greater than the temperature threshold value T_th. If yes, proceed to step S83; if not, proceed to step S85.

Step S83: Modulate the information about the target output power to the input power.

Step S84: Generate input electrical energy corresponding to the target output power.

Step S85: Determine whether the input power Pin is less than the recovery power P_restore and the component temperature Temp is less than the recovery temperature T_restore. If yes, proceed to step S86; if not, proceed to step S84.

Step S86: The transmitting module 10 returns to normal mode and generates input power corresponding to normal output power. Then proceed to step S81.

For details of the wireless charging control method in Figure 8, please refer to the relevant descriptions in Figures 1 to 6B, which will not be elaborated here.

FIG. 9 is a flowchart of a wireless charging control method for a receiving module according to an embodiment of the present invention. The receiving controller 40 of FIG. 1 and the first receiving control unit 41 of FIG. 6B can have a built-in memory, and the wireless charging control method of FIG. 9 can be compiled into a program code and stored in the memory, and includes the following steps.

Step S91: Sample input electrical energy.

Step S92: Determine whether the drive signal PWM is interrupted. If yes, proceed to step S93; if no, proceed to step S95.

Step S93: Demodulate the information about the target output power in the input power.

Step S94: Convert the input electrical energy into the target output power according to the information about the target output power.

Step S95: The receiving module 20 operates in normal mode. Then proceed to step S91.

For details of the wireless charging control method in Figure 9, please refer to the relevant descriptions of Figures 1 to 6B, which will not be elaborated here.

In summary, this case provides a wireless charging control method and a wireless charging system, which controls the transmitting side circuit to operate in a special adjustment mode when the input power or component temperature of the transmitting side is too high, and the receiving side can know that the transmitting side circuit operates in the adjustment mode by sampling the received power, and correspondingly reduce the output power, thereby reducing the input power. In this way, when the distance between the transmitting side and the receiving side increases, the input power can be prevented from excessively increasing and triggering the protection function and interrupting the power transmission, effectively improving the stability of wireless power transmission.

It should be noted that the above is only a preferred embodiment proposed for the purpose of illustrating this case. This case is not limited to the embodiment described above. The scope of this case is determined by the scope of the attached patent application. Moreover, this case can be modified in various ways by people familiar with this technology, but it does not deviate from the scope of the attached patent application to be protected.

S71, S72, S73, S74, S75, S76, S77, S78: Steps

Claims (13)

A wireless charging control method is used in a wireless charging system including a transmitting module and a receiving module, comprising the steps of: (a) determining a target output power according to the input power or the component temperature through the transmitting module when an input power is greater than a power threshold or a component temperature is greater than a temperature threshold; (b) modulating a message about the target output power in an input electric energy through the transmitting module; (c) receiving and sampling the input electric energy through the receiving module to demodulate the message about the target output power; and (d) converting the input electric energy into the target output power according to the message about the target output power through the receiving module. A wireless charging control method as described in claim 1, wherein the input power is a pulse width modulation signal, and the step (b) includes: (b1) determining an interruption number according to the input power or the component temperature; and (b2) interrupting a drive signal of the transmitting module once in the (i*a)th switching cycle to modulate the information about the target output power in the input power; wherein a is an interval number, 0≦i≦(n-1), i*a is less than or equal to a charging cycle, n is the interruption number, and a, i, and n are positive integers. The wireless charging control method as described in claim 2, wherein the step (c) includes: (c1) capturing a falling edge of a switching cycle to a rising edge of the next switching cycle to sample the input power; (c2) when the time difference between the falling edge and the rising edge is detected for the first time to be greater than half a switching cycle, starting to accumulate the charging cycle through a first counter, and starting to accumulate the number of interruptions through a second counter; and (c3) when the charging cycle ends, reading the number of interruptions accumulated by the second counter; wherein when the charging cycle ends, the first counter and the second counter are reset; wherein the number of interruptions is the information about the target output power. A wireless charging control method as described in claim 2, wherein the number of interruptions indicates that the target output power is (100-n*10)% of a rated power, and n is a positive integer less than 10. The wireless charging control method as described in claim 2, wherein the step (b2) includes: generating an enable signal to the transmitting module to interrupt the driving signal. The wireless charging control method as described in claim 1 further comprises the steps of: (e) generating the input electric energy according to the target output power through the transmitting module when at least one of the input power is not less than a recovery power and the component temperature is not less than a recovery temperature is satisfied; and (f) receiving and converting the input electric energy into the target output power through the receiving module. The wireless charging control method as described in claim 6 further comprises the steps of: (g) when the input power is lower than the recovery power and the component temperature is lower than the recovery temperature, controlling the transmitting module to return to a normal mode to generate a normal input power; and (h) receiving and sampling the normal input power through the receiving module to return the receiving module to the normal mode. A wireless charging control method as described in claim 6, wherein the recovery power is equal to 80% of the power threshold value, and the recovery temperature is equal to 80% of the temperature threshold value. A wireless charging system comprises: a transmitting module configured to convert an input power into an input electric energy and then transmit it; and a receiving module configured to receive the input electric energy and convert the input electric energy into an output electric energy to a load; wherein the transmitting module and the receiving module are configured to execute the wireless charging control method as described in claim 1. A wireless charging system as described in claim 9, wherein the transmitting module comprises: a transmitting controller configured to sample an input power, sense a component temperature and generate a driving signal; a driving circuit electrically connected to the transmitting controller; a switching circuit electrically connected to the driving circuit, wherein the driving circuit and the switching circuit are configured to convert the input power into the input electrical energy according to the driving signal; a transmitting coil coupled to the switching circuit and configured to transmit the input electrical energy; a first capacitor connected between the switching circuit and the transmitting coil and configured to match the transmitting coil; and a second capacitor connected between the switching circuit and the transmitting coil and configured to match the transmitting coil. A wireless charging system as described in claim 10, wherein the transmitting controller comprises: a first transmitting control unit, electrically connected to the driving circuit, configured to generate the driving signal to the driving circuit; and a second transmitting control unit, electrically connected to the driving circuit, configured to generate an enable signal to the driving circuit according to the input power and the component temperature, wherein the enable signal is used to interrupt the driving signal. A wireless charging system as described in claim 9, wherein the receiving module comprises: a receiving coil configured to receive the input power; a rectifying circuit coupled to the receiving coil; a step-down circuit electrically connected to the rectifying circuit, wherein the rectifying circuit and the step-down circuit are configured to convert the input power into the output power; a first receiving control unit electrically connected to the step-down circuit and the receiving coil, configured to sample the input power; a third capacitor electrically connected between the receiving coil and the rectifying circuit, configured to match the receiving coil; and a fourth capacitor electrically connected between the receiving coil and the rectifying circuit, configured to match the receiving coil. The wireless charging system as described in claim 12, wherein the receiving module further comprises: a communication circuit electrically connected to the receiving coil and configured to reflect an operating state of the receiving module to the transmitting module; a second receiving control unit electrically connected to the rectifier circuit and the communication circuit and configured to control the operation of the rectifier circuit and the communication circuit; and a buck control unit electrically connected to the buck circuit and the first receiving control unit and configured to control the operation of the buck circuit.

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