A wireless charging transmitter capable of autonomous activation and dormancy and a control method thereof

Abstract

The present invention discloses an autonomously activated and dormant wireless charging transmitter and a control method, wherein the device comprises: a high-frequency full-bridge inverter circuit, which is used to be connected to a DC voltage source and comprises four switch tubes; an LCC compensation topology network, which is connected to the high-frequency inverter; a charging module, which is connected to the LCC compensation topology network and comprises a transmitting coil; and a current sampling module, which is used to collect the output current I of the high-frequency full-bridge inverter circuit. in , and collect the current I on the transmitting coil P ; controller, used to adjust the output current I in and current I P Determine the working state of the wireless charging transmitter, and output four PWM pulse signals according to the working state to control the four switch tubes on the high-frequency full-bridge inverter circuit. When the present invention is in the standby working state, the transmitting coil current is automatically greatly reduced, reducing the energy loss caused by the coil current in the standby state of the traditional device, improving the overall efficiency of the system, and can be widely used in the field of wireless power transmission technology.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power transmission, and in particular to an autonomously activated and dormant wireless charging transmitter and a control method. Background Art

[0002] Inductive Power Transfer (IPT) technology is a technology that uses magnetic field coupling to transmit electrical energy. This technology breaks away from the limitations of physical connections and does not require traditional cable electrical connections and mechanical plugging and unplugging. It has the advantages of safety, reliability, efficiency, flexibility and convenience. At present, this technology has broad application prospects in dynamic wireless charging (DWPT) of electric vehicles (Electric Vehicle, EV), and has been widely concerned and studied by the industry.

[0003] In the commonly used LCC compensated wireless charging system, the transmitter coil on the ground is always excited by a constant standby current, so the receiver coil on the vehicle can be coupled for charging once it covers the transmitter coil. As for the DWPT system, in most cases, even if there is no electric vehicle charging, the ground transmitter coil is still activated at full power to output power waiting for the receiver, which usually leads to huge standby current and electromagnetic exposure and other safety issues.

[0004] Therefore, the dynamic wireless charging system for electric vehicles requires that the magnetic field of the transmitting coil is effectively suppressed when the system is in standby state. The current solutions are mainly divided into two measures: passive shielding and active suppression. For the passive shielding solution, whether it is the addition of an active loop to generate a relative magnetic field that offsets the magnetic field of the transmitting coil, or the use of shielded magnetic cores, the generation of electromagnetic exposure is not fundamentally reduced. For the active suppression solution, some researchers use multiple auxiliary coils or tunnel magnetoresistance (TMR) sensors to detect the position of the electric vehicle, thereby controlling the activation and dormancy of charging. However, additional devices need to be added, which is costly. In addition, some researchers have applied a position sensor-free algorithm to control power transmission. However, this solution relies on bilateral wireless communication feedback, and the risk of communication delay or failure is unacceptable in the DWPT system and increases the control complexity. In addition, interoperability is also important for electric vehicle detection methods in practice, but existing solutions do not fully consider this factor. Therefore, it is challenging to use a simple, effective and interoperable EV detection method to control the activation and dormancy of the wireless charging transmitter of the DWPT system while avoiding auxiliary circuits and wireless communications. Summary of the invention

[0005] In order to solve at least one of the technical problems existing in the prior art to a certain extent, the present invention aims to provide a wireless charging transmitter device and a control method capable of autonomous activation and sleep.

[0006] The technical solution adopted by the present invention is:

[0007] A wireless charging transmitter capable of autonomous activation and dormancy, comprising:

[0008] A high-frequency full-bridge inverter circuit, used for connecting to a DC voltage source, comprises four switching tubes;

[0009] An LCC compensation topology network connected to the high frequency inverter;

[0010] A charging module, connected to the LCC compensation topology network, comprising a transmitting coil;

[0011] A current sampling module is used to collect the output current I of the high-frequency full-bridge inverter circuit. in , and collect the current I on the transmitting coil P ;

[0012] controller, used to adjust the output current I in and current I P The working state of the wireless charging transmitter is determined, and four PWM pulse signals are output according to the working state to control the four switch tubes on the high-frequency full-bridge inverter circuit.

[0013] Furthermore, the working state includes a standby state and a charging state;

[0014] If it is determined to be in the standby state, the working angular frequency of the wireless charging transmitter is controlled by four PWM pulse signals to jump to the first preset angular frequency ω h , to reduce the current on the transmitting coil;

[0015] If it is determined to be in the charging state, the working angular frequency of the wireless charging transmitting device is controlled to jump to the second preset angular frequency ω0 through four PWM pulse signals.

[0016] Furthermore, the LCC compensation topology network includes a compensation inductor L f , parallel compensation capacitor C f And series compensation capacitor C P ;

[0017] Compensation inductance L f One end of the high-frequency full-bridge inverter circuit is connected to the first arm to compensate for the inductance L f The other end is connected in parallel with the compensation capacitor C f Connect one end of the compensation capacitor C in parallel fThe other end is connected to the other bridge arm of the high-frequency full-bridge inverter circuit, and the compensation capacitor C is connected in series P One end of the compensation inductor L f The other end is connected to the series compensation capacitor C P The other end of the transmitting coil L P One end of the transmitting coil L P The other end is connected to the other bridge arm of the high-frequency full-bridge inverter circuit.

[0018] Furthermore, at any operating frequency, the inductive reactance of the compensation inductor is The capacitive reactance of the parallel compensation capacitor is The capacitive reactance of the series compensation capacitor is The inductive reactance of the transmitting coil is The impedance of the transmitting coil branch is Output current I in The expression is:

[0019]

[0020] The current ratio of the primary LCC compensation network is

[0021] Furthermore, the second preset angular frequency ω0 is the resonant operating angular frequency of the wireless charging transmitter, and the expression is as follows:

[0022]

[0023] At the resonant operating angular frequency, the capacitance of the parallel compensation capacitor is The capacitance of the series compensation capacitor is

[0024] Furthermore, when the wireless charging transmitter is in the standby state, the controller outputs a phase shift angle of θ=θ h The four-way PWM control signal is sent to the switch tube of the high-frequency full-bridge inverter circuit, where 0°<θ<180°. At this time, the effective value of the output voltage of the high-frequency full-bridge inverter circuit is:

[0025]

[0026] Where k is the harmonic order; V IN is the DC voltage source voltage;

[0027] In the standby state, the controller jumps the working angular frequency of the wireless charging transmitter to the first preset angular frequency ω h , to ensure the standby current of the transmitting coil at this operating angular frequency At this point, the standby current of the transmitting coil is reduced to:

[0028]

[0029] in, is the standby current of the transmitting coil at the resonant frequency, V in is the inverter output voltage.

[0030] Furthermore, corresponding to the charging module, the total equivalent impedance of the electric energy receiving circuit of the secondary power receiving side electric vehicle is Z S When the secondary electric vehicle and the transmitting coil have an electromagnetic coupling with mutual inductance M, the secondary circuit is equivalent to the mapped impedance mapped to the primary side in series with the transmitting coil

[0031] Furthermore, when the wireless charging transmitter is in a charging state, the secondary electric vehicle receiving coil is coupled with the transmitting coil of the wireless charging transmitter, the wireless charging transmitter operates at a resonant angular frequency ω0, the controller output phase shift angle is θ=0°, and the current ratio of the primary LCC compensation network is

[0032] When the secondary electric vehicle leaves, the secondary circuit is equivalent to the mapped impedance Z on the primary coil r =0, the current ratio of the original LCC compensation network is At this time, there is a primary LCC compensation current ratio dormancy threshold α0, which is used as a criterion for judging the electric vehicle leaving the charging state, where At this time, the controller changes the phase shift angle to θ = θ h And hop frequency to the first preset angular frequency ω h , the wireless charging transmitter automatically stops power transmission and enters standby mode.

[0033] Furthermore, when the wireless charging transmitting device is in a standby state, there is no receiving coil on the secondary side coupled with the transmitting coil of the device, and the wireless charging transmitting device operates at a first preset angular frequency ω h , the controller output phase shift angle is θ=θ h , the current ratio of the original LCC compensation network is:

[0034]

[0035] When the secondary electric vehicle arrives, the mapping impedance of the secondary circuit equivalent to the primary coil is Z r , the current ratio of the original LCC compensation network is:

[0036]

[0037] At this time, there is a primary LCC compensation current ratio activation threshold α h It can be used as a criterion for judging the arrival of electric vehicles in the standby state, where At this time, the controller changes the phase shift angle to θ=0° and hops the frequency to the second preset angular frequency ω0, and the wireless charging transmitter automatically activates power transmission and enters the charging mode.

[0038] Furthermore, the wireless charging transmitter only relies on the difference in the mapped impedance to the LCC compensation current ratio, is desensitized to the secondary-side compensation of different topologies and the battery loads of electric vehicles of different specifications, and has excellent interoperability with common electric vehicles on the market.

[0039] Another technical solution adopted by the present invention is:

[0040] The control method for the above-mentioned autonomously activated and dormant wireless charging transmitter comprises the following steps:

[0041] Collect the output current I of the high-frequency full-bridge inverter circuit in and the current I on the transmitting coil P ;

[0042] According to the output current I in and current I P Determine the working state of the wireless charging transmitter, and output four PWM pulse signals according to the working state to control the four switch tubes on the high-frequency full-bridge inverter circuit, so that different currents are output on the transmitting coil when the wireless charging transmitter works in different states. It only relies on the difference in the mapping impedance to the LCC compensation current ratio, desensitizes to the secondary compensation of different topologies and different specifications of electric vehicle battery loads, and has excellent interoperability with common electric vehicles on the market.

[0043] The beneficial effects of the present invention are as follows: when the secondary electric vehicle receiving circuit is off, the wireless charging transmitter of the present invention switches to a standby working state, the transmitting coil current is automatically greatly reduced, a weak standby current is maintained, the magnetic field exposure of the standby coil is reduced, and safety is improved; the energy loss caused by the coil current in the standby state of the traditional wireless charging transmitter is reduced, and the overall efficiency of the system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the embodiments of the present invention or the drawings of related technical solutions in the prior art are introduced below. It should be understood that the drawings introduced below are only for the convenience of clearly describing some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0045] Figure 1 It is a topological structure principle diagram of a wireless charging transmitter capable of autonomous activation and dormancy in an embodiment of the present invention;

[0046] Figure 2 yes Figure 1 Equivalent analysis diagram of

[0047] Figure 3 is a curve diagram showing the relationship between the standby current and the operating frequency of the transmitting coil in an embodiment of the present invention;

[0048] Figure 4 is a schematic diagram of the autonomous activation and sleep process of dynamic wireless charging in an embodiment of the present invention;

[0049] Figure 5 is a flow chart of the control strategy in an embodiment of the present invention;

[0050] Figure 6 is an interoperability analysis diagram of the sleep / activation control strategy in an embodiment of the present invention;

[0051] Figure 7 It is a schematic diagram of simulation analysis results in an embodiment of the present invention.

[0052] Reference numerals:

[0053] 1. DC voltage source, 2. High-frequency full-bridge inverter circuit, 3. Primary-side LCC compensation network, 4. Loose coupling unit between the transmitting coil of the wireless charging transmitter and the receiving coil of the electric vehicle, 5. Secondary-side compensation network, 6. Full-bridge rectifier circuit, 7. Filter capacitor, 8. Battery load, 9. Current sampling module, 10. System controller module, 11. Wireless charging transmitter. DETAILED DESCRIPTION

[0054] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limitations of the present invention. For the step numbers in the following embodiments, they are only provided for the convenience of explanation, and the order between the steps is not limited in any way, and the execution order of each step in the embodiment can be adaptively adjusted according to the understanding of those skilled in the art.

[0055] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0056] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0057] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0058] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a wireless charging transmitter that can be activated and dormant autonomously. The device can determine the presence of the secondary electric vehicle only by relying on the current of the primary LCC compensation network, and realize the function of autonomous activation and dormant system power output. The device does not require additional wireless communication modules and position detection devices for the primary and secondary sides, and has a simple structure and convenient control. The device automatically activates power transmission when the secondary electric vehicle receiving circuit arrives, which is stable and reliable. The device switches to the standby working state when the secondary electric vehicle receiving circuit leaves, and the current of the transmitting coil is automatically greatly reduced to maintain a weak standby current, reduce the energy loss caused by the coil current in the standby state of the traditional device, and improve the overall efficiency of the system. The device effectively suppresses the electromagnetic exposure of the transmitting coil in the standby state, reduces the harm to the surrounding ecology, and is safe and reliable. In addition, under a certain current sampling accuracy, the device is desensitized to the compensation network and battery specifications of the secondary electric vehicle, and has excellent interoperability with common electric vehicles on the market.

[0059] like Figure 1 As shown, this embodiment provides an autonomously activated and dormant wireless charging transmitter 11, including a high-frequency full-bridge inverter circuit 2, an LCC compensation topology network 3, a primary transmitting coil in a loosely coupled unit 4, a current sampling module 9, and a system controller 10. In addition, as a power receiving end, the electric vehicle circuit includes a secondary receiving coil in the loosely coupled unit 4, a secondary compensation network 5, a full-bridge rectifier circuit 6, a filter capacitor 7, and an electric vehicle battery load 8. Among them, the DC voltage source 1 serves as an energy input end.

[0060] The primary LCC compensation topology network includes the compensation inductor L f , parallel compensation capacitor C f And series compensation capacitor C P The charging coil is a transmitting coil L P The input and output terminals of the DC voltage source are connected to the input and output terminals of the high-frequency full-bridge inverter circuit respectively. fOne end of the high-frequency full-bridge inverter circuit is connected to the first arm to compensate for the inductance L f The other end is connected in parallel with the compensation capacitor C f Connect one end of the compensation capacitor C in parallel f The other end is connected to the other bridge arm of the high-frequency full-bridge inverter circuit, and the compensation capacitor C is connected in series P One end of the compensation inductor L f And parallel compensation capacitor C f The node is connected to the series compensation capacitor C P The other end of the transmitting coil L P One end of the transmitting coil L P The other end is connected to the other bridge arm of the high-frequency full-bridge inverter circuit and the parallel compensation capacitor C f Node connection.

[0061] refer to Figure 1 and Figure 2 , the loop equation of the system can be obtained from the system equivalent circuit diagram, where V in is the output voltage of the high-frequency full-bridge inverter circuit, I in is the output current of the high-frequency full-bridge inverter circuit, I P is the primary transmitting coil current, and its matrix expression satisfies the following formula:

[0062]

[0063] in, To compensate the inductance of the primary side and the inductive reactance of the transmitting coil, is the capacitive reactance of the original compensation capacitor, is the total impedance of the secondary circuit Z S Equivalent to the mapped impedance of the primary transmitting coil.

[0064] When the secondary electric vehicle does not reach the coupling with the transmitting coil, Z r =0, the wireless charging transmitter is in standby state, and the standby current of the transmitting coil is:

[0065]

[0066] In order to suppress the transmitting coil current of the device in the standby state, reduce the power loss when idle, and suppress the electromagnetic exposure of the standby current at this time, the system controller adopts the PWM phase shift composite frequency hopping control strategy. When the controller applies a phase shift angle θ to the high-frequency inverter circuit, its output voltage is:

[0067]

[0068] At the same time, according to formula (2), the standby current I of the transmitting coil of the device is P,standby As the operating frequency ω increases, it first increases to the maximum value point ωx After that, it decreases monotonically, such as Figure 3 At the same time, there is a frequency point ω'0 where the standby current is the same as the resonant operating point ω0, so ω'0 is used as the frequency hopping threshold and the frequency hopping point ω is selected. h >ω'0 can further reduce the coil standby current.

[0069] The desired wireless charging transmitter can autonomously activate and sleep power transmission according to the arrival / departure of electric vehicles. Its working diagram is shown in Figure 4 shown.

[0070] When the system is in the charging state, the secondary electric vehicle receiving coil is coupled with the transmitting coil of the wireless charging transmitter, the system operates at the resonant angular frequency ω0, and the controller output phase shift angle is θ=0°. Figure 2 It can be seen that the current ratio of the original LCC compensation network is:

[0071]

[0072] At this time, the electric car leaves, and the secondary circuit is equivalent to the mapped impedance Z on the primary coil. r =0, the current ratio of the original LCC compensation network is:

[0073]

[0074] At this time, the original LCC compensation current is higher than the dormant threshold α0, which can be used as a criterion for judging the electric vehicle leaving the charging state, where Once the current ratio α<α0 is sampled and calculated in real time, it can be determined that the electric vehicle has left. At this time, the controller changes the phase shift angle to θ=θ h And hop to ω h , the device automatically stops power transmission and enters standby mode.

[0075] When the system is in standby mode, there is no coupling between the receiving coil of the secondary side and the transmitting coil of the wireless charging transmitter, and the system operates at the resonant angular frequency ω h , the controller output phase shift angle is θ=θ h , at this time according to Figure 2 It can be seen that the current ratio of the original LCC compensation network is:

[0076]

[0077] At this time, the electric car arrives, and the secondary circuit is equivalent to the mapped impedance Z on the primary coil. r ≠0, the current ratio of the original LCC compensation network is:

[0078]

[0079] At this time, there is a primary LCC compensation current ratio activation threshold α h It can be used as a criterion for judging the arrival of electric vehicles in the standby state, where Once the current ratio α<α is sampled and calculated in real time h , it can be determined that the electric vehicle has arrived, the controller changes the phase shift angle to θ = 0° and hops back to the resonant angular frequency ω0, the device automatically activates power transmission and enters charging mode.

[0080] In summary, the device can detect whether the secondary electric vehicle is coupled or not by only sampling and calculating the primary current ratio in real time, and has the function of autonomous activation and dormant power transmission, realizing effective suppression of coil current and electromagnetic exposure in standby state. The controller autonomous activation and dormancy control process is as follows: Figure 5 At the same time, since the control strategy adopted by the device only relies on the mapping impedance Z of the secondary circuit on the primary coil r , desensitized to the different compensation network topologies and battery load specifications used in electric vehicles, so the device has excellent interoperability with common electric vehicles on the market.

[0081] According to the above analysis, the original DC voltage source, high-frequency inverter circuit, LCC compensation network, transmitter coil self-inductance selection, operating frequency and phase shift angle parameter values ​​are shown in Table 1. Figure 6 As shown, compared with ordinary wireless charging transmitters, the transmitting coil current and electromagnetic exposure level of the device of the present invention are suppressed by more than 94.6% when in standby mode.

[0082] At the same time, three common topologies of series, parallel and LCC are selected as the equivalent circuit compensation network of the secondary electric vehicle, and 0.5 to 3 times the optimal load corresponding to each compensation is selected as the equivalent battery load for functional verification and interoperability analysis. The simulation analysis results are as follows Figure 7 As shown in Figure 2, under a certain current sampling accuracy, for different types of electric vehicles, it is only necessary to select an appropriate current ratio threshold α according to the mapping impedance. h , α0, the device can effectively identify the common electric vehicles on the market and realize the functions of autonomous activation and dormant power transmission, so the device of the present invention has excellent interoperability.

[0083] Table 1

[0084] name Parameter Value <![CDATA[DC voltage source / V IN > 50V <![CDATA[High-frequency inverter circuit MOSFETs / Q1-Q4]]> IPP60R165 <![CDATA[Self-inductance of primary and secondary power transmission coils / L P 、L S > 109μH、108.5μH <![CDATA[Original compensation network / L f , C f , C P > 33.6μH, 306nF, 135.7nF <![CDATA[Secondary side series and parallel compensation network / C SS 、C SP > 93.7nF, 93.38nF <![CDATA[Secondary LCC Compensation Network / L t , C t , C S > 26.8μH, 124.02nF, 378.06nF Rectifier circuit diode MBR20200 <![CDATA[Resonant frequency, hopping frequency / f0, f h > 50kHz

[0085] In summary, the device of the present invention has the following advantages and beneficial effects compared with the prior art:

[0086] (1) The present invention effectively suppresses the standby current of the transmitting coil of the device when the electric vehicle is in a standby state when the electric vehicle is not coupled with the wireless charging transmitting device, greatly reduces energy loss, improves the overall efficiency of the system, and effectively suppresses the electromagnetic exposure of the transmitting coil in the standby state, which is safe and reliable.

[0087] (2) Based on the LCC compensation topology, the present invention can autonomously identify the coupling state of the electric vehicle through the compensation network current ratio. During the dynamic charging process of the electric vehicle, it can autonomously switch the charging / standby working mode as needed, and dynamically activate and sleep the transmitting coil of the wireless charging transmitter to transmit power. The device does not rely on additional communication modules and position detection devices, has a simple structure, and is easy to operate.

[0088] (3) The present invention is desensitized to secondary compensation networks of different topologies and electric vehicle battery loads of different specifications. Under a certain current sampling accuracy, it can realize dynamic activation and dormancy of power transmission by relying solely on the current ratio of the primary LCC compensation network, and has excellent interoperability with common electric vehicles on the market.

[0089] See also Figure 5 For the above-mentioned autonomously activated and dormant wireless charging transmitting device, this embodiment also provides a control method, including the following steps:

[0090] S1, collect the output current I of the high-frequency full-bridge inverter circuit in and the current I on the transmitting coil P ;

[0091] S2, according to the output current I in and current I P Determine the working state of the wireless charging transmitter, and output four PWM pulse signals according to the working state to control the four switch tubes on the high-frequency full-bridge inverter circuit, so that different currents are output on the transmitting coil when the wireless charging transmitter works in different states.

[0092] A control method of this embodiment has a one-to-one correspondence with the above-mentioned autonomously activated and dormant wireless charging transmitter device, and therefore has corresponding functions and beneficial effects of the device.

[0093] In the above description of this specification, the description with reference to the terms "one embodiment / example", "another embodiment / example" or "certain embodiments / examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0094] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0095] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the above embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A wireless charging transmitter capable of autonomous activation and dormancy, characterized in that: include: A high-frequency full-bridge inverter circuit, used for connecting to a DC voltage source, comprises four switching tubes; An LCC compensation topology network connected to the high-frequency full-bridge inverter circuit; A charging module, connected to the LCC compensation topology network, comprising a transmitting coil; A current sampling module is used to collect the output current I of the high-frequency full-bridge inverter circuit. in , and collect the current I on the transmitting coil P ; controller, used to adjust the output current I in and the current I on the transmitting coil P Determine the working state of the wireless charging transmitter, and output four PWM pulse signals according to the working state to control the four switch tubes on the high-frequency full-bridge inverter circuit; The LCC compensation topology network includes a compensation inductor L f , parallel compensation capacitor C f And series compensation capacitor C P ; Compensation inductance L f One end of the high-frequency full-bridge inverter circuit is connected to the first arm to compensate for the inductance L f The other end is connected in parallel with the compensation capacitor C f Connect one end of the compensation capacitor C in parallel f The other end is connected to the other bridge arm of the high-frequency full-bridge inverter circuit, and the compensation capacitor C is connected in series P One end of the compensation inductor L f The other end is connected to the series compensation capacitor C P The other end of the transmitting coil L P One end of the transmitting coil L P The other end is connected to the other bridge arm of the high-frequency full-bridge inverter circuit; At any operating frequency, the inductive reactance of the compensation inductor is The capacitive reactance of the parallel compensation capacitor is The capacitive reactance of the series compensation capacitor is The inductive reactance of the transmitting coil is The impedance of the transmitting coil branch is Output current I in The expression is: The current ratio of the primary LCC compensation network is Corresponding to the charging module, the total equivalent impedance of the electric energy receiving circuit of the secondary power receiving side electric vehicle is Z S When the secondary electric vehicle and the transmitting coil have an electromagnetic coupling with mutual inductance M, the secondary circuit is equivalent to the mapped impedance mapped to the primary side in series with the transmitting coil When the wireless charging transmitter is in the charging state, the secondary electric vehicle receiving coil is coupled with the transmitting coil of the wireless charging transmitter, the wireless charging transmitter operates at the resonant angular frequency ω0, the controller output phase shift angle is θ=0°, and the current ratio of the primary LCC compensation network is When the secondary electric vehicle leaves, the secondary circuit is equivalent to the mapped impedance Z on the primary coil r =0, the current ratio of the original LCC compensation network is At this time, there is a primary LCC compensation current ratio dormancy threshold α0, which is used as a criterion for judging the electric vehicle leaving the charging state, where At this time, the controller changes the phase shift angle to θ = θ h And hop frequency to the first preset angular frequency ω h , the wireless charging transmitter automatically stops power transmission and enters standby mode.

2. The autonomously activated and dormant wireless charging transmitter according to claim 1, characterized in that: The working state includes a standby state and a charging state; If it is determined to be in the standby state, the working angular frequency of the wireless charging transmitter is controlled by four PWM pulse signals to jump to the first preset angular frequency ω h , to reduce the current on the transmitting coil; If it is determined to be in the charging state, the working angular frequency of the wireless charging transmitting device is controlled to jump to the second preset angular frequency ω0 through four PWM pulse signals.

3. The autonomously activated and dormant wireless charging transmitter according to claim 1, characterized in that: The second preset angular frequency ω0 is the resonant operating angular frequency of the wireless charging transmitter, and the expression is as follows: At the resonant operating angular frequency, the capacitance of the parallel compensation capacitor is The capacitance of the series compensation capacitor is 4. The autonomously activated and dormant wireless charging transmitter according to claim 1, characterized in that: When the wireless charging transmitter is in standby mode, the controller outputs a phase shift angle of θ = θ h The four-way PWM control signal is sent to the switch tube of the high-frequency full-bridge inverter circuit, where 0°<θ<180°. At this time, the effective value of the output voltage of the high-frequency full-bridge inverter circuit is: Where k is the harmonic order; V IN is the DC voltage source voltage; In the standby state, the controller jumps the working angular frequency of the wireless charging transmitter to the first preset angular frequency ω h , to ensure the standby current of the transmitting coil at this operating angular frequency At this point, the standby current of the transmitting coil is reduced to: in, is the standby current of the transmitting coil at the resonant frequency, V in is the inverter output voltage.

5. The autonomously activated and dormant wireless charging transmitter according to claim 1, characterized in that: When the wireless charging transmitting device is in standby mode, there is no receiving coil on the secondary side coupled with the transmitting coil of the device, and the wireless charging transmitting device operates at the first preset angular frequency ω h , the controller output phase shift angle is θ=θ h , the current ratio of the original LCC compensation network is: When the secondary electric vehicle arrives, the mapping impedance of the secondary circuit equivalent to the primary coil is Z r , the current ratio of the original LCC compensation network is: At this time, there is a primary LCC compensation current ratio activation threshold α h It can be used as a criterion for judging the arrival of electric vehicles in the standby state, where At this time, the controller changes the phase shift angle to θ=0° and hops the frequency to the second preset angular frequency ω0, and the wireless charging transmitter automatically activates power transmission and enters the charging mode.

6. A control method for a wireless charging transmitter capable of autonomous activation and dormancy according to any one of claims 1 to 5, characterized in that: The following steps are involved: Collect the output current I of the high-frequency full-bridge inverter circuit in and the current I on the transmitting coil P ; According to the output current I in and current I P Determine the working state of the wireless charging transmitter, and output four PWM pulse signals according to the working state to control the four switch tubes on the high-frequency full-bridge inverter circuit, so that different currents are output on the transmitting coil when the wireless charging transmitter works in different states.

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