CN212063636U - Wireless power transmission device based on composite LCC compensation - Google Patents
Wireless power transmission device based on composite LCC compensation Download PDFInfo
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- CN212063636U CN212063636U CN202020853584.8U CN202020853584U CN212063636U CN 212063636 U CN212063636 U CN 212063636U CN 202020853584 U CN202020853584 U CN 202020853584U CN 212063636 U CN212063636 U CN 212063636U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/7072—Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/72—Electric energy management in electromobility
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/10—Technologies relating to charging of electric vehicles
- Y02T90/14—Plug-in electric vehicles
Abstract
The utility model provides a wireless electric energy transmission device based on composite LCC compensation, which comprises a transmitting module and a receiving module; the transmitting module comprises a direct-current power supply, a high-frequency inverter circuit, a transmitting terminal compensation network and a primary transmitting coil which are sequentially connected; the receiving module comprises a secondary receiving coil, a receiving end compensation network, a rectification filter circuit and a load which are connected in sequence; the transmitting terminal compensation network comprises a switch S1、S2Primary side LCC compensation netRoad sum with change-over switch S3The primary side of the primary side is connected in series with the compensation network; the receiving end compensation network comprises a secondary LCC compensation network; closing the change-over switch S1、S2And opening the switch S3Realizing a bilateral LCC constant current charging mode; switch off change-over switch S1、S2And closing the change-over switch S3And realizing the S-LCC constant voltage charging mode. Implement the utility model discloses, can overcome the shortcoming and not enough that prior art exists, and circuit structure is simple, and is with low costs.
Description
Technical Field
The utility model relates to a wireless power transmission technology and novel energy conversion technical field especially relate to a wireless power transmission device based on compensation of compound LCC.
Background
The appearance of the wireless power transmission technology can effectively overcome a series of defects of the traditional wired power supply mode, such as: the device has poor moving flexibility, unattractive environment, easy generation of contact spark, exposed power supply line and the like, and is particularly suitable for safe power supply of mobile devices, electric automobiles, flammable and explosive environments, underwater and oil field underground equipment. Therefore, the wireless power transmission technology is widely applied to many fields.
Generally, the most common load is a battery, but the equivalent resistance of the battery is constantly changed, and the charging process comprises two charging stages of constant current and constant voltage, namely, a constant current mode is adopted in the initial charging stage, so that the voltage of the battery can rapidly rise, and when the voltage of the battery reaches a required value, the charging mode is changed into a constant voltage mode, the voltage is maintained stable, and the charging current is gradually reduced until the current is cut off, so that the charging is finished. The charging mode requires the wireless electric energy transmission device to provide constant current and voltage, so that the safe and reliable charging of the battery is realized, and the service life and the charging and discharging times of the battery can be prolonged.
However, the following methods are available for the conventional wireless power transmission device to realize constant-current constant-voltage switching charging: firstly, frequency conversion control is adopted, namely the wireless electric energy transmission device respectively realizes constant voltage output and constant current output under different frequencies, but the frequency bifurcation phenomenon can be caused, so that the device is unstable in operation; and secondly, a DC-DC direct current converter is added after the secondary rectification output for regulation, but the method is not suitable for the situation of large load change in order to avoid the occurrence of limit duty ratio, and the system volume is increased due to the addition of a direct current conversion circuit. And thirdly, closed-loop negative feedback control is introduced into the circuit, and phase shift control is adopted, but too many devices are added, and the control cost and complexity are improved.
Therefore, there is a need for a wireless power transmission device capable of realizing constant-current and constant-voltage switching charging, which can overcome the disadvantages and shortcomings of the prior art, and has a simple circuit structure and low cost.
SUMMERY OF THE UTILITY MODEL
The embodiment of the utility model provides a technical problem that will solve lies in, provides a wireless power transmission device based on compensation of compound LCC, can overcome the shortcoming and not enough that prior art exists, and circuit structure is simple, and is with low costs.
In order to solve the above technical problem, an embodiment of the present invention provides a wireless power transmission device based on composite LCC compensation, including a transmitting module and a receiving module, which transmits energy with the transmitting module through electromagnetic induction; wherein the content of the first and second substances,
the transmitting module comprises direct current power supplies U connected in sequenceinHigh-frequency inverter circuit, transmitting end compensation network and primary transmitting coil LP(ii) a Wherein the transmitting terminal compensation network comprises an inductor Lf1And a series capacitor C1Parallel capacitor cpAnd a change-over switch S1And a change-over switch S2A primary LCC compensation network formed by the primary LCC compensation network and a series capacitor C3And a change-over switch S3A primary side series compensation network is formed; the primary LCC compensation network is connected in parallel with the primary series compensation network and is connected with the primary transmitting coil LP；
The receiving module comprises secondary receiving coils L connected in sequenceSThe receiving end compensation network, the rectification filter circuit and the load; wherein the receiving end compensation network comprises an inductor Lf2In series with a capacitor C2And a parallel capacitor CSA secondary LCC compensation network is formed;
by closing the change-over switch S1、S2And opening the switch S3Then the primary LCC compensation network and the secondary LCC compensation network form a constant current with output independent of loadThe bilateral LCC compensation network realizes a bilateral LCC constant current charging mode;
by opening the change-over switch S1、S2And closing the change-over switch S3And then obtaining an S-LCC compensation network which is formed by the primary side series compensation network and the secondary side LCC compensation network and has constant voltage output irrelevant to the load, and realizing an S-LCC constant voltage charging mode.
Wherein the high frequency inverter circuit comprises a switching transistor Q1Switching transistor Q2Switching transistor Q3And a switching transistor Q4(ii) a Wherein the content of the first and second substances,
switching transistor Q1、Q4Switching transistors Q connected in series2Switching transistor Q3Switching transistors Q connected in series1Switching transistor Q4With switching transistor Q in series2Switching transistor Q3Are connected in parallel.
Wherein the rectifying and filtering circuit comprises a diode D1Diode D2Diode D3Diode D4And a capacitor C4(ii) a Wherein the content of the first and second substances,
diode D1Diode D4Connected in series, diode D2Diode D3Connected in series and a capacitor C4Diode D after series connection1Diode D4And a diode D connected in series2Diode D3The three are connected in parallel.
Wherein the primary transmitting coil LPAnd the secondary receiving coil LSThe mutual inductance between them is M.
Implement the embodiment of the utility model provides a, following beneficial effect has:
1. the utility model discloses only need to construct transmitting terminal compensation network in the primary circuit of loose coupling transformer, its circuit structure is simple, with low costs, and only need simple control switch to switch during operation, just can realize the switching of circuit output constant current constant voltage, not only control simply, conveniently, reliably, do not have complicated control strategy, also need not primary circuit and secondary circuit to communicate;
2. the primary side and the secondary side of the loose coupling transformer are both LCC type compensation networks, so that the device can output constant current and constant voltage irrelevant to the load under the same working frequency, the requirements of initial constant current charging and later constant voltage charging of the battery are met, and meanwhile, the device can work under a frequency point, the frequency bifurcation phenomenon can not occur, and the work is stable;
3. the utility model discloses specifically be applied to the static wireless charging of electric motor car, primary and secondary coil relative position are fixed mutually and are felt value M fixed, and the size of load resistance among the receiving module is discerned to voltage, current signal among the accessible real-time detection transmitting module, obtains charging voltage, electric current, the resistance of electric motor car at different moments among the power transmission process, can therefore trail adjusting device to make the electric motor car charge reliable and stable.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings obtained from these drawings still belong to the scope of the present invention without inventive laboriousness.
Fig. 1 is a schematic circuit connection diagram of a wireless power transmission device based on composite LCC compensation according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings.
As shown in fig. 1, in order to provide the wireless power transmission device based on composite LCC compensation in the embodiment of the present invention, the wireless power transmission device includes a transmitting module 1 and a receiving module 2 that transmits energy with the transmitting module 1 through electromagnetic induction; wherein the content of the first and second substances,
the transmitting module 1 comprises sequentially connected direct currentSource 11, high frequency inverter circuit 12, transmitting terminal compensation network 13 and primary transmitting coil LP(ii) a Wherein, the transmitting terminal compensation network 13 comprises an inductor Lf1And a series capacitor C1Parallel capacitor cpAnd a change-over switch S1And a change-over switch S2A primary LCC compensation network formed by the primary LCC compensation network and a series capacitor C3And a change-over switch S3A primary side series compensation network is formed; the primary LCC compensation network is connected in parallel with the primary series compensation network and connected with the primary transmitting coil LP；
The receiving module 2 comprises secondary receiving coils L connected in sequenceSA receiving end compensation network 21, a rectification filter circuit 22 and a load 23; wherein, the receiving end compensation network 21 comprises an inductor Lf2In series with a capacitor C2And a parallel capacitor CSA secondary LCC compensation network is formed; wherein the primary transmitting coil LPAnd a secondary receiving coil LSForming a loose coupling transformer, wherein the mutual inductance between the loose coupling transformer and the loose coupling transformer is M;
by closing the change-over switch S1、S2And opening the switch S3Then, a primary LCC compensation network and a secondary LCC compensation network form a double-side LCC compensation network which outputs constant current irrelevant to the load, and a double-side LCC constant current charging mode is realized;
by opening the change-over switch S1、S2And closing the change-over switch S3And forming an S-LCC compensation network with constant voltage output independent of the load by the primary side series compensation network and the secondary side LCC compensation network to realize an S-LCC constant voltage charging mode.
In the embodiment of the present invention, the high frequency inverter circuit 12 includes a switching transistor Q1Switching transistor Q2Switching transistor Q3And a switching transistor Q4(ii) a Wherein the content of the first and second substances,
switching transistor Q1Switching transistor Q4Switching transistors Q connected in series2Switching transistor Q3Switching transistors Q connected in series1Switching transistor Q4With switching transistor Q in series2Switching transistor Q3Are connected in parallel.
In the embodiment of the present invention, the rectifying and filtering circuit 22 includes a diode D1Diode D2Diode D3Diode D4And a capacitor C4(ii) a Wherein the content of the first and second substances,
diode D1Diode D4Connected in series, diode D2Diode D3Connected in series and a capacitor C4Diode D after series connection1Diode D4And a diode D connected in series2Diode D3The three are connected in parallel.
The embodiment of the utility model provides an in wireless power transmission device's theory of operation based on compound LCC compensation does:
in the transmitting module 1, a rectification power supply 11 is connected in parallel with the input end of a high-frequency inverter circuit 12 to supply power to the whole system; the high-frequency inverter circuit 12 inverts the direct current into alternating current; the transmitting terminal compensation network 13 is connected in parallel with the output terminal of the high frequency inverter circuit 12, the output of the high frequency inverter circuit 12 is used as an excitation source, and the primary side LCC compensation network, the primary side series (S) compensation network and the primary transmitting coil L are connected in seriesPCan reach a resonance state under the working frequency; in the receiving module 2, a secondary receiving coil LSThe primary side electric energy can be coupled to the secondary side through the electromagnetic induction principle; the receiving end compensates the output received by the network 21 and can reach a resonance state under the working frequency; the rectifying and filtering circuit 22 converts the alternating current into direct current and stabilizes the voltage.
Wherein the changeover switch S is closed1、S2And opening the switch S3Then, a primary LCC compensation network and a secondary LCC compensation network form a double-side LCC compensation network which outputs constant current irrelevant to the load, and a double-side LCC constant current charging mode is realized; by opening the change-over switch S1、S2And closing the change-over switch S3And forming an S-LCC compensation network with constant voltage output independent of the load by the primary side series compensation network and the secondary side LCC compensation network to realize an S-LCC constant voltage charging mode. The above twoThe side LCC compensation network and the S-LCC compensation network are both LCC type, so that a composite LCC compensation network is formed together.
Implement the embodiment of the utility model provides a, following beneficial effect has:
1. the utility model discloses only need to construct transmitting terminal compensation network in the primary circuit of loose coupling transformer, its circuit structure is simple, with low costs, and only need simple control switch to switch during operation, just can realize the switching of circuit output constant current constant voltage, not only control simply, conveniently, reliably, do not have complicated control strategy, also need not primary circuit and secondary circuit to communicate;
2. the primary side and the secondary side of the loose coupling transformer are both LCC type compensation networks, so that the device can output constant current and constant voltage irrelevant to the load under the same working frequency, the requirements of initial constant current charging and later constant voltage charging of the battery are met, and meanwhile, the device can work under a frequency point, the frequency bifurcation phenomenon can not occur, and the work is stable;
3. the utility model discloses specifically be applied to the static wireless charging of electric motor car, primary and secondary coil relative position are fixed mutually and are felt value M fixed, and the size of load resistance among the receiving module is discerned to voltage, current signal among the accessible real-time detection transmitting module, obtains charging voltage, electric current, the resistance of electric motor car at different moments among the power transmission process, can therefore trail adjusting device to make the electric motor car charge reliable and stable.
The above disclosure is only a preferred embodiment of the present invention, and certainly should not be taken as limiting the scope of the invention, which is defined by the claims and their equivalents.
Claims (4)
1. A wireless power transmission device based on composite LCC compensation is characterized by comprising a transmitting module and a receiving module, wherein the receiving module transmits energy through electromagnetic induction with the transmitting module; wherein the content of the first and second substances,
the transmitting module comprises a direct current power supply, a high-frequency inverter circuit, a transmitting terminal compensation network and a primary terminal which are sequentially connectedStage transmitting coil LP(ii) a Wherein the transmitting terminal compensation network comprises an inductor Lf1And a series capacitor C1Parallel capacitor cpAnd a change-over switch S1And a change-over switch S2A primary LCC compensation network formed by the primary LCC compensation network and a series capacitor C3And a change-over switch S3A primary side series compensation network is formed; the primary LCC compensation network is connected in parallel with the primary series compensation network and is connected with the primary transmitting coil LP；
The receiving module comprises secondary receiving coils L connected in sequenceSThe receiving end compensation network, the rectification filter circuit and the load; wherein the receiving end compensation network comprises an inductor Lf2In series with a capacitor C2And a parallel capacitor CSA secondary LCC compensation network is formed;
by closing the change-over switch S1、S2And opening the switch S3Then, a primary LCC compensation network and a secondary LCC compensation network form a double-side LCC compensation network which outputs constant current irrelevant to the load, and a double-side LCC constant current charging mode is realized;
by opening the change-over switch S1、S2And closing the change-over switch S3And then obtaining an S-LCC compensation network which is formed by the primary side series compensation network and the secondary side LCC compensation network and has constant voltage output irrelevant to the load, and realizing an S-LCC constant voltage charging mode.
2. The wireless power transfer device based on composite LCC compensation of claim 1, wherein the high frequency inverter circuit comprises a switching transistor Q1Switching transistor Q2Switching transistor Q3And a switching transistor Q4(ii) a Wherein the content of the first and second substances,
switching transistor Q1Switching transistor Q4Switching transistors Q connected in series2Switching transistor Q3Switching transistors Q connected in series1Switching transistor Q4With switching transistor Q in series2、Q3Are connected in parallel.
3. The wireless power transfer device based on composite LCC compensation of claim 1, wherein the rectifying-filtering circuit comprises a diode D1Diode D2Diode D3Diode D4And a capacitor C4(ii) a Wherein the content of the first and second substances,
diode D1Diode D4Connected in series, diode D2Diode D3Connected in series and a capacitor C4Diode D after series connection1Diode D4And a diode D connected in series2Diode D3The three are connected in parallel.
4. The wireless power transfer apparatus based on composite LCC compensation of claim 1, wherein the primary transmit coil LPAnd the secondary receiving coil LSThe mutual inductance between them is M.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113147435A (en) * | 2021-03-04 | 2021-07-23 | 广西电网有限责任公司电力科学研究院 | Wireless charging system and control method |
| CN113629799A (en) * | 2021-07-13 | 2021-11-09 | 广西电网有限责任公司电力科学研究院 | Wireless charging system and method for switching constant-current constant-voltage charging mode |
| CN113794287A (en) * | 2021-09-15 | 2021-12-14 | 西南交通大学 | Constant-current and constant-voltage charging wireless power transmission system based on two-channel T-shaped circuit |
| CN114142627A (en) * | 2021-12-14 | 2022-03-04 | 西南交通大学 | Wireless power transmission system |
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2020
- 2020-05-20 CN CN202020853584.8U patent/CN212063636U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113147435A (en) * | 2021-03-04 | 2021-07-23 | 广西电网有限责任公司电力科学研究院 | Wireless charging system and control method |
| CN113629799A (en) * | 2021-07-13 | 2021-11-09 | 广西电网有限责任公司电力科学研究院 | Wireless charging system and method for switching constant-current constant-voltage charging mode |
| CN113794287A (en) * | 2021-09-15 | 2021-12-14 | 西南交通大学 | Constant-current and constant-voltage charging wireless power transmission system based on two-channel T-shaped circuit |
| CN113794287B (en) * | 2021-09-15 | 2023-08-04 | 西南交通大学 | Constant-current-constant-voltage charging wireless power transmission system based on double-channel T-shaped circuit |
| CN114142627A (en) * | 2021-12-14 | 2022-03-04 | 西南交通大学 | Wireless power transmission system |
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