Wireless charging device, wireless charging system and wireless charging method

Abstract

The invention provides a wireless charging device, a wireless charging system and a wireless charging method, and the device comprises a wireless charging chip which generates a power adjustment signal; the filtering module is used for filtering the power regulation signal to obtain regulation voltage; the feedback module is used for feeding back the regulation voltage to the AC-to-DC module; the AC-to-DC module adjusts the value of the DC voltage based on the output signal of the feedback module; and the transformer is used for converting the output voltage of the AC-to-DC module into the power supply voltage of the wireless charging chip. The adapter and the wireless charger are combined together, negotiation time is shortened, BOM is reduced, cost is reduced, stability is excellent, and cost reduction and efficiency improvement of enterprises are reasonably helped; and the charging power is adjusted in real time based on the error data of the wireless charging receiving end, so that the accuracy is higher.

Description

Technical Field

[0001] The present invention relates to the field of wireless charging, and particularly to a wireless charging device, a wireless charging system and a wireless charging method. Background Art

[0002] Wireless charging technology (Wireless charging technology; Wireless charge technology) originates from wireless power transmission technology. The power supply device (charger) transmits energy to the electrical device, and the device uses the received energy to charge the battery and operate itself at the same time. Since there is no wire connection between the charger and the electrical device, both the charger and the electrical device can be made without exposed conductive contacts, and the safety is higher. Wireless charging has become an emerging charging method in people's lives.

[0003] Existing wireless charging devices need to be used in cooperation with an adapter, that is, the adapter supplies power to the wireless charging device, and the wireless charging device then provides corresponding energy to the electrical device based on electromagnetic induction or magnetic resonance. The adapter needs to adjust the voltage supplied to the wireless charging device according to the request for adjusting the power fed back by the wireless charging device to meet the charging requirements of the electrical device. The existing way of using wireless charging devices in cooperation with adapters has poor reliability; and due to the long feedback mechanism, the negotiation time becomes longer and the real-time performance becomes worse; in addition, the cost of the protocol chip used for establishing communication is also relatively high.

[0004] Therefore, how to provide a wireless charging device with high real-time performance, high reliability and low cost has become one of the problems that need to be solved urgently by those skilled in the art.

[0005] It should be noted that the above introduction of the technical background is only for the convenience of clearly and completely explaining the technical solution of the present invention and facilitating the understanding of those skilled in the art. It cannot be considered that the above technical solutions are well-known to those skilled in the art just because these solutions are described in the background art part of the present invention. Summary of the Invention

[0006] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a wireless charging device, a wireless charging system and a wireless charging method, which are used to solve the problems of long wireless charging feedback mechanism and high cost in the prior art.

[0007] To achieve the above purpose and other related purposes, the present invention provides a wireless charging device, which at least includes:

[0008] A wireless charging chip, a filtering module, a feedback module, an AC-DC conversion module and a transformer;

[0009] The wireless charging chip is used to provide energy and generate a power regulation signal based on a power regulation request provided externally;

[0010] The filtering module is connected to the output end of the wireless charging chip, filters the power regulation signal, and obtains a regulated voltage;

[0011] The feedback module is connected to the output end of the filtering module, and feeds back the regulated voltage to the AC-DC conversion module;

[0012] The AC-DC conversion module is connected to the output end of the feedback module and receives an AC input voltage, and is used to convert the AC input voltage into a DC voltage and adjust the value of the DC voltage based on the output signal of the feedback module;

[0013] The primary coil of the transformer is connected to the AC-DC conversion module, and the secondary coil is connected to the wireless charging chip, and is used to convert the output voltage of the AC-DC conversion module into the power supply voltage of the wireless charging chip.

[0014] Optionally, the wireless charging chip includes a transmitting coil, a power output stage, a feedback unit, and a transmitting end communication control unit;

[0015] The power output stage is connected to the transmitting coil to form a resonant circuit, generates an electromagnetic signal based on the electric energy provided by the transformer, and transmits it;

[0016] The feedback unit is connected to the output end of the power output stage and is connected to the transmitting end communication control unit;

[0017] The transmitting end communication control unit receives a power regulation request, demodulates the power regulation request, and generates the power regulation signal and the control signal of the wireless charging chip.

[0018] More optionally, the transmitting end communication control unit includes a transmitting current estimation module, a subtractor, a proportional integral derivative module, and a power regulation signal generation module;

[0019] The transmitting current estimation module is connected to the output end of the feedback unit, and calculates a predicted transmitting current based on the power error data of the current request period provided by the power regulation request and the actual transmitting current of the previous request period;

[0020] The subtractor is connected to the output ends of the transmitting current estimation module and the feedback unit, subtracts the predicted transmitting current from the actual transmitting current of the previous adjustment period, and obtains an error value;

[0021] The proportional integral derivative module is connected to the output end of the subtractor, and performs proportional integral derivative operation based on the error value;

[0022] The power adjustment signal generation module is connected to the output end of the proportional integral derivative module, and generates and adjusts the power adjustment signal based on the output signal of the proportional integral derivative module.

[0023] More optionally, the power adjustment signal is a PWM signal.

[0024] Optionally, the filtering module is an RC filtering structure.

[0025] More optionally, the filtering module includes a first capacitor, a second capacitor and a resistor; the first end of the resistor serves as the input end of the filtering module, and the second end serves as the output end of the filtering module; the upper plate of the first capacitor is connected to the first end of the resistor, and the lower plate is grounded; the upper plate of the second capacitor is connected to the second end of the resistor, and the lower plate is grounded.

[0026] Optionally, the feedback module is an optocoupler.

[0027] Optionally, the AC input voltage is 220V.

[0028] More optionally, the wireless charging device further includes a housing, and the wireless charging chip, the filtering module, the feedback module, the AC-DC conversion module and the transformer are arranged in the housing.

[0029] To achieve the above and other related purposes, the present invention also provides a wireless charging system, which at least includes:

[0030] A wireless charging transmitter and a wireless charging receiver;

[0031] The wireless charging transmitter is implemented by using the above wireless charging device, communicates with the wireless charging receiver and provides energy to the wireless charging receiver;

[0032] The wireless charging receiver senses the energy output by the wireless charging transmitter, converts the sensed energy into a DC power supply, and sends a power adjustment request to the wireless charging transmitter.

[0033] To achieve the above and other related purposes, the present invention also provides a wireless charging method, which is implemented based on the above wireless charging system, and the wireless charging method at least includes:

[0034] The wireless charging receiver sends a power adjustment request to the wireless charging transmitter;

[0035] The wireless charging transmitter generates a power adjustment signal based on the power adjustment request, and the power adjustment signal is filtered to obtain an adjustment voltage; based on the adjustment voltage, the magnitude of the DC voltage is adjusted, and further the power of the energy output by the wireless charging transmitter is changed.

[0036] The wireless charging transmitter transmits energy to the wireless charging receiver to meet the power requirement of the wireless charging receiver.

[0037] Optionally, the method for generating the power regulation signal includes:

[0038] 1) Obtain power error data of the current request period based on the power regulation request, and calculate a predicted transmission current based on the power error data of the current request period and the actual transmission current of the previous request period;

[0039] 2) Subtract the actual transmission current of the previous adjustment period from the predicted transmission current to obtain an error value. If the error value is equal to 0, end the adjustment and execute step 6); if the error value is not equal to 0, continue to execute step 3);

[0040] 3) Perform proportional-integral-derivative operation based on the error value;

[0041] 4) Adjust the power regulation signal based on the result of the proportional-integral-derivative operation to adjust the actual transmission current;

[0042] 5) Return to step 2) to continuously adjust the actual transmission current within the corresponding adjustment period;

[0043] 6) When receiving the power error data of the next request period, return to step 1).

[0044] More optionally, the predicted transmission current satisfies:

[0045]

[0046] The error value satisfies:

[0047]

[0048] where i is a natural number greater than or equal to 1, and j is a natural number greater than or equal to 1; is the predicted transmission current of the jth request period; is the transmission current of the (j - 1)th request period, is equal to the initial current value; c (j) is the power error data of the jth request period; e (j,i) is the error value; is the actual transmission current of the (i - 1)th adjustment period within the jth request period, is equal to the initial current value when j is greater than or equal to 2, is equal to the actual transmission current of the last adjustment period within the (j - 1)th request period.

[0049] More optionally, the proportional integral derivative operation on the error value satisfies:

[0050] P (j,i) =K P ·e (j,i) ;

[0051] I (j,i) =I (j,i-1) +K i ·e (j,i) ·t inner ;

[0052]

[0053] PID (j,i) =P (j,i) +I (j,i) +D (j,i) ;

[0054] wherein, i is a natural number greater than or equal to 1, and j is a natural number greater than or equal to 1; e (j,i) is the error value of the i-th adjustment period within the j-th request period; e (j,i-1) is the error value of the (i - 1)-th adjustment period within the j-th request period, e (1,0) is equal to the initial error value. When j is greater than or equal to 2, e (j,0) is the error value of the last adjustment period within the (j - 1)-th request period; P (j,i) is the proportional value of the i-th adjustment period within the j-th request period; K P is the linear gain; I (j,i) is the integral value of the i-th adjustment period within the j-th request period; I (j,i-1) is the integral value of the (i - 1)-th adjustment period within the j-th request period, I (1,0) is equal to the initial integral value. When j is greater than or equal to 2, I (j,0) is equal to the integral value of the last adjustment period within the (j - 1)-th request period; K i is the integral gain; t inner is the duration of one adjustment period; D (j,i) is the differential value of the i-th adjustment period within the j-th request period; K d is the differential gain; PID (j,i) is the result of the proportional integral operation.

[0055] More optionally, the adjustment variable of the power adjustment signal satisfies:

[0056] ν (j,i) =ν (j,i-1) -S ν ·PID (j,i) ;

[0057] wherein, ν(j,i) is the adjustment variable for the i-th adjustment period within the j-th request period; ν (j,i-1) is the adjustment variable for the (i - 1)-th adjustment period within the j-th request period, ν (1,0) equals the initial variable value, when j is greater than or equal to 2, ν (j,0) equals the adjustment variable for the last adjustment period within the (j - 1)-th request period; S ν is the adjustment coefficient.

[0058] More optionally, based on the adjustment voltage, the duty cycle of the switching control signal of the DC voltage is adjusted to achieve the adjustment of the magnitude of the DC voltage.

[0059] As described above, the wireless charging device, wireless charging system, and wireless charging method of the present invention have the following beneficial effects:

[0060] The wireless charging device, wireless charging system, and wireless charging method of the present invention combine the adapter with wireless charging, remove the protocol chip, transmit the request for power adjustment through a power adjustment signal in the form of PWM, and filter the power adjustment signal to obtain the feedback level voltage, thereby realizing the adjustment of the output voltage on the secondary side of the transformer, reducing the negotiation time, reducing the BOM (without the protocol chip and its peripheral devices), reducing the cost, and having excellent stability, reasonably helping enterprises reduce costs and increase efficiency.

[0061] The wireless charging device, wireless charging system, and wireless charging method of the present invention obtain the error data of the wireless charging receiving end, calculate the estimated transmission current, calculate the error value between the estimated transmission current and the actual transmission current, perform proportional-integral-derivative operation on the error value, and adjust the charging power in real time according to the proportional-integral-derivative value, with higher accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 Shows the schematic circuit structure diagram of the wireless charging transmitting end.

[0063] Figure 2 Shows as Figure 1 The schematic flow diagram of the wireless charging transmitting end to achieve wireless charging.

[0064] Figure 3 Shows the schematic structure diagram of the wireless charging device of the present invention.

[0065] Figure 4 Shows the schematic structure diagram of the wireless charging chip of the present invention.

[0066] Figure 5 Shows the schematic structure diagram of the transmitting end communication control unit of the present invention.

[0067] Figure 6It shows a schematic structural diagram of the filtering module of the present invention.

[0068] Figure 7 It shows a schematic structural diagram of the wireless charging system of the present invention.

[0069] Figure 8 It shows a schematic structural diagram of the wireless charging receiving end of the present invention.

[0070] Figure 9 It shows a schematic flow diagram of the wireless charging method of the present invention.

[0071] Figure 10 It shows a schematic flow diagram of the generation of the power regulation signal of the present invention.

[0072] Description of Component Labels

[0073] 1 Wireless charging chip

[0074] 2 Adapter

[0075] 21 Protocol chip

[0076] 22 Optocoupler

[0077] 23 AC-DC chip

[0078] 24 Transformer

[0079] 3 Wireless charging device

[0080] 31 Wireless charging chip

[0081] 311 Power output stage

[0082] 312 Feedback unit

[0083] 313 Transmitter communication control unit

[0084] 313a Transmitted current estimation module

[0085] 313b Subtractor

[0086] 313c Proportional integral derivative module

[0087] 313d Power regulation signal generation module

[0088] 32 Filtering module

[0089] 33 Feedback module

[0090] 34 AC to DC module

[0091] 35 Transformer

[0092] 4 Wireless charging receiving end

[0093] 41 Power input stage

[0094] 42 Rectifier unit

[0095] 43 Receiver communication control unit

[0096] 5 Load Detailed implementation manners

[0097] The following uses specific specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0098] Please refer to Figures 1 to 10 . It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The types, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0099] As Figure 1 shown, it is a circuit structure of a wireless charging transmitter, including a wireless charging chip 1 and an adapter 2; wherein, the adapter 2 includes a protocol chip 21 (in order to meet universality, the adapter 2 needs to be provided with a protocol chip 21 to be compatible with different types of wireless charging chips 1 or electrical devices), an optocoupler 22, an AC-DC chip 23, and a transformer 24. The wireless charging chip 1 transfers the regulated power request provided by the wireless charging receiver to the protocol chip 21; the protocol chip 21 establishes communication with the wireless charging chip 1 through negotiation and converts the request for regulated power into a voltage signal recognizable by the adapter 2; then it is fed back to the AC-DC chip 23 through the optocoupler 22, and the AC-DC chip 23 adjusts the output voltage based on the feedback voltage; the primary coil of the transformer 24 is connected to the AC-DC chip 23, and the secondary coil is connected to the wireless charging chip 1. Through the induction of the secondary coil to the primary coil, the output voltage of the AC-DC chip 23 is provided to the wireless charging chip 1 in equal proportion or at a certain proportion, so that the wireless charging chip 1 generates energy for charging the electrical device (i.e., the wireless charging receiver).

[0100] As Figure 2As shown in the figure, the wireless charging process based on the wireless charging chip 1 and the adapter 2 is as follows: The receiving end of wireless charging sends a power adjustment request to the transmitting end (the wireless charging chip 1). The transmitting end (the wireless charging chip 1) communicates with the protocol chip 21 in the adapter 2 to negotiate the power to be output; the protocol chip 21 outputs a feedback voltage to the optocoupler 22; the optocoupler 22 provides the feedback voltage to the AC-DC chip 23; the AC-DC chip 23 adjusts the output voltage based on the feedback voltage; the voltage at the output end of the transformer 24 is adjusted accordingly. Due to the adjustment of the output voltage of the transformer 24, the output power of the transmitting end (the wireless charging chip 1) is also adjusted. The receiving end receives the adjusted power signal and charges with it to obtain the desired charging current and voltage.

[0101] In the circuit structure of the above wireless charging transmitting end, communication needs to be established between the wireless charging chip 1 and the control circuits (including but not limited to the optocoupler 22 and the AC-DC chip 23) inside the adapter 2 through the protocol chip 21, and then a request for feedback power adjustment is sent. When the wireless charging chip 1 and the protocol chip 21 (two or more chips) work together, a long negotiation time is required to reach an agreement. The protocol chip 21 is also configured with complex peripheral circuits (not shown in the figure). The increase in the overall BOM (Bill of Material) quantity results in the increase in the volume of the wireless charging device. Moreover, the price of the protocol chip module is not low, which often discourages many manufacturers who strictly control costs. In addition, projects with more chips are more vulnerable to the impact of the supply and demand relationship in the chip market.

[0102] For the above reasons, the present invention provides a wireless charging device, which reduces the mechanism negotiation time, reduces costs, and improves reliability.

[0103] As Figure 3 shown in the figure, the wireless charging device 3 of the present invention includes:

[0104] A wireless charging chip 31, a filtering module 32, a feedback module 33, an AC-DC conversion module 34, and a transformer 35.

[0105] As Figure 3 shown in the figure, the wireless charging chip 31 is used to provide energy and generate a power adjustment signal PWM based on a power adjustment request provided externally.

[0106] Specifically, the wireless charging chip 31 is used to provide energy and transmit it wirelessly; the wireless charging chip 31 can transmit energy based on the electromagnetic induction method. As Figure 4 shown in the figure, as an example, the wireless charging chip 31 includes a transmitting coil, a power output stage 311, a feedback unit 312, and a transmitting end communication control unit 313.

[0107] More specifically, the power output stage 311 is connected to the transmitting coil to form a resonant circuit, and an electromagnetic signal is generated based on the electric energy provided by the transformer 35 and transmitted.

[0108] More specifically, the feedback unit 312 is connected to the output end of the power output stage 311 and is connected to the transmitting end communication control unit 313; it is used to feedback the output end signal (including but not limited to the transmitting current) of the wireless charging device 3 to the transmitting end communication control unit 313.

[0109] More specifically, the transmitting end communication control unit 313 (communicates with the communication unit in the device to be charged) receives a power adjustment request, demodulates the power adjustment request, and generates the power adjustment signal PWM and the control signal of the wireless charging chip 31. As Figure 5 shown, as an example, the transmitting end communication control unit 313 includes a transmitting current estimation module 313a, a subtractor 313b, a proportional integral derivative module 313c, and a power adjustment signal generation module 313d. The transmitting current estimation module 313a is connected to the output end of the feedback unit 312, and based on the power error data c of the current request period provided by the power adjustment request (j) and the actual transmitting current of the previous request period calculate the estimated transmitting current where j is a natural number greater than or equal to 1, and when j = 1, is configured as the initial current value (including but not limited to 0, set according to actual needs). The subtractor 313b is connected to the output ends of the transmitting current estimation module 313a and the feedback unit 312, and subtracts the estimated transmitting current from the actual transmitting current of the previous adjustment period to obtain an error value e (j,i) ; it should be noted that the request period is a large cycle, and the adjustment period is a small cycle. Each request period includes at least one adjustment period. The proportional integral derivative module 313c is connected to the output end of the subtractor 313a, and performs proportional integral derivative operations based on the error value e (j ,i) The power adjustment signal generation module 313d is connected to the output end of the proportional integral derivative module 313c, and generates and adjusts the power adjustment signal PWM based on the output signal PID (j,i) of the proportional integral derivative module 313c.

[0110] It should be noted that any circuit structure that can implement the function of the wireless charging transmitting end under the condition of providing power is applicable to the present invention, and is not limited to this embodiment.

[0111] Specifically, in this embodiment, the power adjustment signal is a PWM (pulse width modulation) signal, and the magnitude of the power to be adjusted is reflected based on the pulse width.

[0112] As Figure 3 shown, the filtering module 32 is connected to the output end of the wireless charging chip 31, filters the power adjustment signal PWM, and obtains the adjusted voltage Vfb.

[0113] Specifically, in this embodiment, the filtering module 32 is a hardware circuit that filters the power adjustment signal PWM to obtain the adjusted voltage Vfb, and the level of the adjusted voltage Vfb changes continuously. The filtering module 32 includes, but is not limited to, an RC filtering structure, and any filtering structure that can convert the power adjustment signal PWM into a voltage signal with a continuously changing level is applicable to the present invention. As Figure 6 shown, as an example, the filtering module 32 includes a first capacitor C1, a second capacitor C2, and a resistor R. The first end of the resistor R serves as the input end of the filtering module 32, and the second end serves as the output end of the filtering module 32; the upper plate of the first capacitor C1 is connected to the first end of the resistor R, and the lower plate is grounded; the upper plate of the second capacitor C2 is connected to the second end of the resistor R, and the lower plate is grounded. Among them, the first capacitor C1 can be configured as a single capacitor, or a series, parallel, or series-parallel structure of two or more capacitors; similarly, the second capacitor C2 can be configured as a single capacitor, or a series, parallel, or series-parallel structure of two or more capacitors ( Figure 4 in which, the second capacitor C2 is realized by a parallel structure of capacitors C21 and C22); the resistor R can be configured as a single resistor, or a series, parallel, or series-parallel structure of two or more resistors; this is not elaborated one by one here.

[0114] As Figure 3 shown, the feedback module 33 is connected to the output end of the filtering module 32, and feeds back the adjusted voltage Vfb to the AC-DC conversion module 34.

[0115] Specifically, in this embodiment, the feedback module 33 is implemented by an optocoupler; as an example, the optocoupler includes a light-emitting diode and a phototransistor. The light-emitting diode emits light under the drive of the adjusted voltage Vfb; the phototransistor detects the light signal emitted by the light-emitting diode and converts it into a corresponding electrical signal. In actual use, any optocoupler structure or other circuit structure that can achieve signal feedback is applicable to the present invention, and is not limited to this embodiment.

[0116] As Figure 3As shown, the AC-DC conversion module 34 is connected to the output end of the feedback module 33 and receives an AC input voltage, and is configured to convert the AC input voltage into a DC voltage DC and adjust the value of the DC voltage DC based on the output signal of the feedback module 33.

[0117] Specifically, in this embodiment, the AC-DC conversion module 34 adopts a switching power supply structure, and the output signal of the feedback module 33 adjusts the control signal of the power switch tube in the switching power supply structure; further, if the control signal of the power switch tube is a PWM signal, then the duty cycle of the switch tube control signal is adjusted based on the output signal of the feedback module 33, thereby realizing the adjustment of the DC voltage DC. Any circuit structure that can achieve AC-DC conversion and can adjust the value of the output DC voltage is applicable to the present invention, and will not be elaborated here one by one.

[0118] Specifically, in this embodiment, the AC input voltage is configured as 220V; in actual use, the AC input voltage can be configured as needed, including but not limited to 100V and 380V.

[0119] As Figure 3 shown, the primary coil of the transformer 35 is connected to the AC-DC conversion module 34, and the secondary coil is connected to the wireless charging chip 31, and is configured to convert the output voltage of the AC-DC conversion module 34 into the power supply voltage of the wireless charging chip 31.

[0120] Specifically, the transformer 35 includes at least a primary coil and a secondary coil, and an auxiliary coil can also be configured as needed. The turns ratio between the primary coil and the secondary coil is configured as needed, and will not be elaborated here one by one.

[0121] As another implementation manner of the present invention, the wireless charging device 3 further includes a housing (not shown in the figure), and the wireless charging chip 31, the filtering module 32, the feedback module 33, the AC-DC conversion module 34, and the transformer 35 are disposed in the housing.

[0122] The wireless charging device of the present invention integrates the adapter function and the wireless charging function together, without a protocol chip, directly filters the power adjustment signal PWM to obtain an adjustment voltage, and then adjusts the power supply voltage of the wireless charging chip through the adjustment voltage to realize the adjustment of the output power; the present invention reduces the cost of the overall project, reduces the mechanism negotiation time, and improves the reliability.

[0123] As Figure 7 shown, the present invention further provides a wireless charging system, and the wireless charging system includes:

[0124] A wireless charging transmitting end and a wireless charging receiving end 4.

[0125] As Figure 7 shown, the wireless charging transmitter is implemented by the wireless charging device 3 of the present invention. The wireless charging transmitter communicates with the wireless charging receiver 4 and provides energy (output power) to the wireless charging receiver 4.

[0126] As Figure 7 shown, the wireless charging receiver 4 senses the energy output by the wireless charging transmitter, converts the sensed energy into a DC power supply, and sends a power adjustment request to the wireless charging transmitter.

[0127] Specifically, as Figure 8 shown, as an example, the wireless charging receiver 4 includes a receiving coil, a power input stage 41, a rectifying unit 42, and a receiver communication control unit 43; the receiving coil and the power input stage 41 form a resonant circuit to receive the power output by the transmitting coil; the rectifying unit 42 is connected to the output end of the power input stage 41 to convert an AC power signal into a DC power signal (the rectified voltage is Vrect); the receiver communication control unit 43 is used for wireless communication with the transmitter communication control unit 313 to send a power adjustment request to the wireless charging transmitter. Any circuit structure that can implement the function of the wireless charging receiver is applicable to the present invention and is not limited to this embodiment.

[0128] As Figure 7 shown, as another implementation manner of the present invention, the wireless charging system further includes a load 5. The load 5 is connected to the output end of the wireless charging receiver 4 to obtain electrical energy (DC power supply) from the wireless charging receiver 4. As an example, the load 5 can be configured as a power consumption module in a mobile phone, that is, the wireless charging receiver 4 and the load 5 form a mobile phone; any power consumption module can be used as the load 5 and connected to the wireless charging receiver 4 to implement the wireless charging function of the power consumption module, which will not be elaborated here one by one.

[0129] As Figure 9 shown, the present invention also provides a wireless charging method. In this embodiment, the wireless charging method is implemented based on the wireless charging system, and in actual use, any system that can implement this method is applicable. The wireless charging method includes:

[0130] 1) The wireless charging receiver sends a power adjustment request to the wireless charging transmitter.

[0131] Specifically, in this embodiment, the wireless charging receiver 4 monitors the rectified voltage Vrect inside, and sends an error data control packet CEP (power error signal) to the wireless charging transmitter once every certain period of time (as an example, 250 ms). The error data control packet CEP is generated based on the error between the desired power and the actual power. When the wireless charging receiver 4 needs to adjust the power, the power error data carried in the error data control packet CEP is acquired by the wireless charging transmitter. As an example, the error data control packet CEP is wirelessly transmitted through the communication control unit in the wireless charging receiver 4 and the wireless charging chip 31.

[0132] 2) The wireless charging transmitter generates a power adjustment signal based on the power adjustment request. After filtering the power adjustment signal, an adjustment voltage is obtained, and based on the adjustment voltage, the magnitude of the DC voltage is adjusted, thereby changing the power of the energy output by the wireless charging transmitter.

[0133] Specifically, in this embodiment, the transmitter communication control unit 313 in the wireless charging chip decodes the received error data control packet CEP, and then uses the PID algorithm to control the drive to convert DC into AC, which is transmitted to the wireless charging receiver 4 through the transmitting coil. The amplitude modulation signal fed back by the wireless charging receiver 4 is demodulated to restore the data signal, so as to interpret the current state of the wireless charging receiver 4 and generate a power adjustment signal, and the power adjustment signal is a PWM signal. As Figure 10 shown, as an example, the method for generating the power adjustment signal includes:

[0134] 1) Based on the power adjustment request, obtain the power error data of the current request cycle, and calculate the estimated transmitted current based on the power error data of the current request cycle and the actual transmitted current of the previous request cycle.

[0135] Specifically, let the power error data sent by the wireless charging receiver 4 for the jth time be c (j) (power error data of the jth request cycle), be the transmitted current of the transmitting coil of the wireless charging device 3 after being adjusted by the previous power error data c (j-1) , that is, the transmitted current of the (j - 1)th request cycle (when j = 1, that is, the preset initial current value), then the estimated transmitted current of the jth request cycle is:

[0136]

[0137] 2) Subtract the estimated emission current from the actual emission current in the previous adjustment cycle to obtain an error value; if the error value is equal to 0, end the adjustment and execute step 6); if the error value is not equal to 0, continue to execute step 3).

[0138] Specifically, the error value e (j,i) satisfies:

[0139]

[0140] Where it should be noted that j is the number of request cycles (large loops), and receiving a power error data is one request cycle; i is the number of adjustment cycles (small loops), and adjusting the emission current once is one adjustment cycle; each request cycle includes at least one adjustment cycle, and the specific value can be configured as needed. i is a natural number greater than or equal to 1, and j is a natural number greater than or equal to 1. is the actual emission current in the (i - 1)-th adjustment cycle within the j-th request cycle; is equal to the initial current value; when j is greater than or equal to 2, is equal to the actual emission current in the last adjustment cycle within the (j - 1)-th request cycle. Assuming that the error value is equal to 0 at the 4th adjustment cycle in the 3rd request cycle, then, is

[0141] 3) Perform proportional-integral-derivative operation based on the error value.

[0142] Specifically, calculate the proportional, integral, and differential values respectively, satisfying:

[0143] P (j,i) = K P ·e (j,i) (3);

[0144] I (j,i) = I (j,i-1) + K i ·e (j,i) ·t inner (4);

[0145]

[0146] Where P (j,i) is the proportional value in the i-th adjustment cycle within the j-th request cycle; K P is the linear gain; I (j,i) is the integral value in the i-th adjustment cycle within the j-th request cycle; I (j,i-1) is the integral value in the (i - 1)-th adjustment cycle within the j-th request cycle, I (1,0)equals the initial integral value (including but not limited to 0, set according to actual needs). When j is greater than or equal to 2, I (j,0) equals the integral value of the last adjustment period within the (j - 1)-th request period; K i is the integral gain; t inner is the duration of one adjustment period (as an example, 1 ms ≤ t inner ≤ 5 ms); D (j,i) is the differential value of the i-th adjustment period within the j-th request period; K d is the differential gain; e (j,i-1) is the error value of the (i - 1)-th adjustment period within the j-th request period, e (1,0) equals the initial error value (including but not limited to 0, set according to actual needs). When j is greater than or equal to 2, e (j,0) equals the error value of the last adjustment period within the (j - 1)-th request period; I (j ,i) has a value range from -M I to M I .

[0147] Then add the three together to obtain the PID value:

[0148] PID (j,i) = P (j,i) + I (j,i) + D (j,i) (6);

[0149] wherein, the PID has a value range from -M PID to M PID .

[0150] 4) Adjust the power regulation signal based on the result of the proportional-integral-derivative operation to adjust the actual emission current.

[0151] Specifically, adjust the adjustment variable of the variable power regulation signal according to the calculated PID value, thereby adjusting the emission current and the emission power. The adjustment variable of the power regulation signal satisfies:

[0152] ν (j,i) = ν (j,i-1) - S ν ·PID (j,i) (7);

[0153] wherein, ν (j,i) is the adjustment variable of the i-th adjustment period within the j-th request period; ν (j,i-1) is the adjustment variable of the (i - 1)-th adjustment period within the j-th request period, ν (1,0) equals the initial variable value (including but not limited to 0, set according to actual needs). When j is greater than or equal to 2, ν (j,0)is equal to the adjustment variable of the last adjustment period within the (j - 1)-th request period; S ν is the adjustment coefficient. The adjustment variable v (j,i) can be frequency, duty cycle, or the voltage at the input terminal of the inverter. In this embodiment, the adjustment variable v (j,i) is frequency; the adjustment coefficient S V is related to the variable to be controlled and is configured according to the actual application. When the adjustment variable is frequency, the adjustment coefficient S V has different values in different frequency bands, which will not be elaborated here one by one.

[0154] 5) Return to step 2) and continuously adjust the actual emission current within the corresponding adjustment period.

[0155] Specifically, return to step 2) to recalculate the error value. If there is an error, enter the next adjustment period; if there is no error, end the adjustment of the current request period.

[0156] 6) When receiving the power error data of the next request period, return to step 1) to perform the adjustment of each adjustment period within the next request period.

[0157] Specifically, if after executing the set number (as an example, set to 5 times) of adjustment periods within the current request period and the error still exists, the wireless charging receiver 4 sends the next power adjustment request; if the error is adjusted to 0 before executing the set number of adjustment periods within the current request period, stop the power adjustment within the current request period and wait for the wireless charging receiver 4 to send the next power adjustment request. When the wireless charging chip 31 receives the power error data of the next request period, return to step 1) to perform the adjustment of the next request period.

[0158] Meanwhile, the filtering module 32 filters the power adjustment signals of each adjustment period to obtain an adjustment voltage, and the level of the adjustment voltage changes continuously. The adjustment voltage is fed back to the AC-DC conversion module 34 through the feedback module 33, and the AC-DC conversion module 34 adjusts the DC voltage on the input side (primary coil) of the transformer 35 based on the adjustment voltage; in this embodiment, the adjustment voltage is made into data and written into the control software of the AC-DC conversion module 34, and the control software adjusts the output DC voltage of the AC-DC conversion module 34 by adjusting the duty cycle of the PWM control signal of the power switch tube; in actual use, the control of the AC-DC conversion module 34 can be implemented by a hardware circuit, which is not limited to this embodiment. The voltage magnitude on the output side (secondary coil) of the transformer 35 is adjusted accordingly, thereby changing the output power of the wireless charging chip 31.

[0159] 3) The wireless charging transmitter transfers energy to the wireless charging receiver 4 to meet the power requirement of the wireless charging receiver 4.

[0160] Specifically, the wireless charging chip 31 transfers energy to the wireless charging receiver 4, and the wireless charging receiver 4 charges based on the received energy.

[0161] The above steps 1)-3) are continuously cycled. The wireless charging transmitter monitors the charging status in real time and adjusts the power continuously to make the power of the wireless charging receiver meet the requirement.

[0162] The present invention improves the feedback link of the adapter 220V voltage, with small volume, low cost and higher stability.

[0163] In summary, the present invention provides a wireless charging device, a wireless charging system and a wireless charging method, including: a wireless charging chip, a filtering module, a feedback module, an AC-DC conversion module and a transformer; the wireless charging chip is used to provide energy and generate a power adjustment signal based on a power adjustment request provided externally; the filtering module is connected to the output end of the wireless charging chip to filter the power adjustment signal to obtain an adjusted voltage; the feedback module is connected to the output end of the filtering module to feedback the adjusted voltage to the AC-DC conversion module; the AC-DC conversion module is connected to the output end of the feedback module and receives an AC input voltage, and is used to convert the AC input voltage into a DC voltage and adjust the value of the DC voltage based on the output signal of the feedback module; the primary coil of the transformer is connected to the AC-DC conversion module, and the secondary coil is connected to the wireless charging chip, and is used to convert the output voltage of the AC-DC conversion module into the power supply voltage of the wireless charging chip. The wireless charging device, the wireless charging system and the wireless charging method of the present invention combine the adapter with the wireless charger, transfer the power adjustment request through a PWM-form power adjustment signal, filter the power adjustment signal to obtain the feedback level voltage, and then realize the adjustment of the output voltage on the secondary side of the transformer, reduce the negotiation time, reduce the BOM (without the protocol chip and its peripheral devices), reduce the cost, and have excellent stability, reasonably helping enterprises to reduce costs and increase efficiency; also, the charging power is adjusted in real time based on the error data of the wireless charging receiver, with higher accuracy. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0164] The above embodiments are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A wireless charging device, characterized in that, The wireless charging device at least includes: a wireless charging chip, a filtering module, a feedback module, an AC-DC conversion module, and a transformer; The wireless charging chip is used to provide energy and generate a power adjustment signal based on a power adjustment request provided externally; The filtering module is connected to the output end of the wireless charging chip, filters the power adjustment signal, and obtains an adjusted voltage; The feedback module is connected to the output end of the filtering module and feeds back the adjusted voltage to the AC-DC conversion module; The AC-DC conversion module is connected to the output end of the feedback module, receives an AC input voltage, is used to convert the AC input voltage into a DC voltage, and adjusts the value of the DC voltage based on the output signal of the feedback module; The primary coil of the transformer is connected to the AC-DC conversion module, and the secondary coil is connected to the wireless charging chip, and is used to convert the output voltage of the AC-DC conversion module into the power supply voltage of the wireless charging chip.

2. The wireless charging device according to claim 1, characterized in that: The wireless charging chip includes a transmitting coil, a power output stage, a feedback unit, and a transmitting end communication control unit; The power output stage is connected to the transmitting coil to form a resonant circuit, generates an electromagnetic signal based on the electric energy provided by the transformer, and transmits it; The feedback unit is connected to the output end of the power output stage and is connected to the transmitting end communication control unit; The transmitting end communication control unit receives a power adjustment request, demodulates the power adjustment request, and generates the power adjustment signal and the control signal of the wireless charging chip.

3. The wireless charging device according to claim 2, characterized in that: The transmitting end communication control unit includes a transmitting current estimation module, a subtractor, a proportional integral derivative module, and a power adjustment signal generation module; The transmitting current estimation module is connected to the output end of the feedback unit, and calculates a predicted transmitting current based on the power error data of the current request period provided by the power adjustment request and the actual transmitting current of the previous request period; The subtractor is connected to the output ends of the transmitting current estimation module and the feedback unit, subtracts the predicted transmitting current from the actual transmitting current of the previous adjustment period, and obtains an error value; The proportional integral derivative module is connected to the output end of the subtractor and performs proportional integral derivative operations based on the error value; The power adjustment signal generation module is connected to the output end of the proportional integral derivative module, and generates and adjusts the power adjustment signal based on the output signal of the proportional integral derivative module.

4. The wireless charging device according to claim 1, characterized in that: The filtering module is an RC filtering structure.

5. The wireless charging device according to claim 2, characterized in that: The filtering module includes a first capacitor, a second capacitor, and a resistor; the first end of the resistor serves as the input end of the filtering module, and the second end serves as the output end of the filtering module; the upper plate of the first capacitor is connected to the first end of the resistor, and the lower plate is grounded; the upper plate of the second capacitor is connected to the second end of the resistor, and the lower plate is grounded.

6. The wireless charging device according to any one of claims 1-5, characterized in that: The wireless charging device further includes a housing, and the wireless charging chip, the filtering module, the feedback module, the AC-DC conversion module, and the transformer are arranged in the housing.

7. A wireless charging system, characterized in that, The wireless charging system at least includes: a wireless charging transmitting end and a wireless charging receiving end; The wireless charging transmitter is implemented by using the wireless charging device according to any one of claims 1-6, communicates with the wireless charging receiver, and provides energy to the wireless charging receiver; The wireless charging receiver senses the energy output by the wireless charging transmitter, converts the sensed energy into a DC power supply, and sends a power adjustment request to the wireless charging transmitter.

8. A wireless charging method, implemented based on the wireless charging system according to claim 7, characterized in that, The wireless charging method at least includes: The wireless charging receiver sends a power adjustment request to the wireless charging transmitter; The wireless charging transmitter generates a power adjustment signal based on the power adjustment request, obtains an adjustment voltage after filtering the power adjustment signal; adjusts the magnitude of the DC voltage based on the adjustment voltage, and further changes the power of the energy output by the wireless charging transmitter; The wireless charging transmitter transmits energy to the wireless charging receiver to meet the power requirement of the wireless charging receiver.

9. The wireless charging method according to claim 8, characterized in that: The method for generating the power adjustment signal includes: 1) Obtain power error data of the current request cycle based on the power adjustment request, and calculate an estimated transmission current based on the power error data of the current request cycle and the actual transmission current of the previous request cycle; 2) Subtract the actual transmission current of the previous adjustment cycle from the estimated transmission current to obtain an error value. If the error value is equal to 0, end the adjustment and execute step 6); if the error value is not equal to 0, continue to execute step 3); 3) Perform proportional-integral-derivative operation based on the error value; 4) Adjust the power adjustment signal based on the result of the proportional-integral-derivative operation to adjust the actual transmission current; 5) Return to step 2) to continuously adjust the actual transmission current within the corresponding adjustment cycle; 6) When receiving the power error data of the next request cycle, return to step 1).

10. The wireless charging method according to claim 9, wherein: The estimated transmission current satisfies: The error value satisfies: Wherein, i is a natural number greater than or equal to 1, and j is a natural number greater than or equal to 1; is the estimated emission current in the j-th request period; is the emission current in the (j - 1)-th request period, equals the initial current value; c (j) is the power error data in the j-th request period; e (j,i) is the error value; is the actual emission current in the (i - 1)-th adjustment period within the j-th request period, equals the initial current value when j is greater than or equal to 2, equals the actual emission current in the last adjustment period within the (j - 1)-th request period.

11. The wireless charging method according to claim 9 or 10, wherein: Performing proportional-integral-derivative operation on the error value satisfies: P (j,i) = K P · e (j,i) ; I (j,i) = I (j,i-1) + K i · e (j,i) · t inner ; PID (j,i) = P (j,i) + I (j,i) + D (j,i) ; where i is a natural number greater than or equal to 1, and j is a natural number greater than or equal to 1; e (j,i) is the error value of the i-th adjustment period within the j-th request period; e (j,i-1) is the error value of the (i - 1)-th adjustment period within the j-th request period, e (1,0) equals the initial error value, when j is greater than or equal to 2, e (j,0) equals the error value of the last adjustment period within the (j - 1)-th request period; P (j,i) is the proportional value of the i-th adjustment period within the j-th request period; K P is the linear gain; I (j,i) is the integral value of the i-th adjustment period within the j-th request period; I (j ,i-1) is the integral value of the (i - 1)-th adjustment period within the j-th request period, I (1,0) equals the initial integral value, when j is greater than or equal to 2, I (j,0) equals the integral value of the last adjustment period within the (j - 1)-th request period; K i is the integral gain; t inner is the duration of one adjustment period; D (j,i) is the differential value of the i-th adjustment period within the j-th request period; K d is the differential gain; PID (j,i) is the result of the proportional-integral operation.

12. The wireless charging method according to claim 11, wherein: The adjustment variable of the power adjustment signal satisfies: ν (j,i) = ν (j,i-1) - S ν ·PID (j,i) ; where, ν (j,i) is the adjustment variable for the i-th adjustment period within the j-th request cycle; ν (j,i-1) is the adjustment variable for the (i - 1)-th adjustment period within the j-th request cycle, and ν (1,0) equals the initial variable value. When j is greater than or equal to 2, ν (j,0) equals the adjustment variable for the last adjustment period within the (j - 1)-th request cycle; S ν is the adjustment coefficient.

13. The wireless charging method according to any one of claims 8 - 12, wherein: Adjust the duty cycle of the switching control signal of the DC voltage based on the adjustment voltage to achieve the adjustment of the magnitude of the DC voltage.

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