CN115065174A - Wireless energy transfer system based on electromagnetic metamaterial and impedance matching method - Google Patents

Wireless energy transfer system based on electromagnetic metamaterial and impedance matching method Download PDF

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Publication number
CN115065174A
CN115065174A CN202210848307.1A CN202210848307A CN115065174A CN 115065174 A CN115065174 A CN 115065174A CN 202210848307 A CN202210848307 A CN 202210848307A CN 115065174 A CN115065174 A CN 115065174A
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coil
electromagnetic metamaterial
transmitting
wireless energy
system based
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Chinese (zh)
Inventor
徐彬
李晓南
刘国强
罗兵
徐永生
肖微
曾向君
王婷婷
张豪峰
陈少杰
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Institute of Electrical Engineering of CAS
CSG Electric Power Research Institute
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Institute of Electrical Engineering of CAS
CSG Electric Power Research Institute
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/10—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling
    • H02J50/12—Circuit arrangements or systems for wireless supply or distribution of electric power using inductive coupling of the resonant type
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/14—Inductive couplings
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J50/00—Circuit arrangements or systems for wireless supply or distribution of electric power
    • H02J50/70—Circuit arrangements or systems for wireless supply or distribution of electric power involving the reduction of electric, magnetic or electromagnetic leakage fields
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/38—Impedance-matching networks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/14—Inductive couplings
    • H01F2038/146—Inductive couplings in combination with capacitive coupling
    • 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
    • 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
    • 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 invention relates to a wireless energy transfer system based on an electromagnetic metamaterial and an impedance matching method. The signal source provides a sine wave signal with the frequency of 3.5MHz and the power of 13 dBm; the power amplifier adopts an A, B class amplifying circuit, and the gain is 31 dB; adjustable capacitor C in broadband impedance matcher 3 And C 4 Respectively adjusting the return loss amplitude and the resonant frequency value in the system; the transmitting coil and the receiving coil are formed by winding litz wires and adopt a circular structure; the resonance frequency of the electromagnetic metamaterial is 3.5 MHz; the load is a low voltage bulb. The inventionThe wireless energy transmission system based on the electromagnetic metamaterial and the impedance matching method can meet the requirement of improving the energy transmission efficiency of the wireless energy transmission system.

Description

Wireless energy transfer system based on electromagnetic metamaterial and impedance matching method
Technical Field
The invention belongs to the field of wireless energy transmission system design and radio frequency system impedance matching, and particularly relates to a wireless energy transmission system based on an electromagnetic metamaterial and an impedance matching method.
Background
The wireless energy transmission technology supplies power to the load in a non-connection mode, and is widely applied to the field of power supply of power equipment. Because the magnetic coupling resonant wireless energy transfer technology has the advantages of large energy transfer capacity, high transmission efficiency, long energy transfer distance, wide transmission direction and the like, the magnetic coupling resonant wireless energy transfer technology has attracted general attention as a novel electric energy storage and transmission technology. The key of the transmission efficiency in the magnetic coupling resonant wireless energy transmission technology is system impedance matching. If the impedance matching is poor, the transmission efficiency is very low and most of the energy will be reflected.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides a wireless energy transfer system based on an electromagnetic metamaterial and an impedance matching method, the method is high in practicability and wide in application range, and the problem of poor impedance matching in the system can be effectively solved, so that the impedance values of devices in the system can reach 50+ j0 omega.
In order to realize the purpose, the invention adopts the technical scheme that:
a wireless energy transfer system based on an electromagnetic metamaterial comprises a power output port, a transmitting port, the electromagnetic metamaterial, a receiving port and a load port; the power output port comprises a signal source, a power amplifier and a broadband impedance matcher; the transmitting port comprises a transmitting end matching capacitor C 1 And a transmitting coil; the receiving port comprises a receiving end matching capacitor C 2 And a receiving coil; the load of the load port is a low-voltage bulb; the signal source is connected with the power amplifier in series; the power amplifier is connected with a broadband impedance matcher in series; the broadband impedance matcher is connected with a transmitting port in series; the transmitting terminal is matched with a capacitor C 1 A ground terminal lead connected in series to the transmitting coil; the receiving end matching capacitor C 2 A ground terminal lead connected in series to the receiving coil; the transmitting coil and the receiving coil are separated by air, and energy is transmitted through magnetic induction resonance; the receive port is connected in series with a load port.
Furthermore, the number of turns of the transmitting coil and the receiving coil is 15, and the distance between the turns is 0.5 cm; the circumference of the outermost coil is 94.24cm, and the circumference of the innermost coil is 37.71 cm.
Furthermore, three mica capacitors connected in parallel are externally connected inside the broadband impedance matcher, and the capacitance values of the three mica capacitors are 3000PF, 1500PF and 1500 PF; also comprises an adjustable capacitor C 3 And C 4 The impedance matching range of the two adjustable capacitors is (2-45) omega +/-j (0-70) omega; the inductance of the inner inductor was 100 μ H.
Furthermore, the power amplifier comprises a power amplifier signal output port, a filter and a coupler, wherein a signal output by the power amplifier signal output port is input into the filter, processed by the filter, and enters the coupler of the power monitoring circuit to be processed, and then power is output.
Further, the rated voltage value of the low-voltage bulb is 5V, and the power is 5W.
Furthermore, the side length a of the electromagnetic metamaterial unit lattice of the electromagnetic metamaterial is 100mm, the maximum side length b of the square spiral coil in the electromagnetic metamaterial unit is 96mm, the width w of a lead in the coil is 0.5mm, the coil turn distance s is 0.5mm, and the number N of coil turns is 19.
Further, the distance between the transmitting coil and the electromagnetic metamaterial is 10cm, and the distance between the receiving coil and the electromagnetic metamaterial is 10-100 cm.
The invention also provides an impedance matching method of the wireless energy transmission system based on the electromagnetic metamaterial, which is based on a frequency resonance formula
Figure BDA0003753871760000021
Measuring self inductance and parasitic capacitance of the transmitting coil and the receiving coil, and matching the transmitting end with a capacitor C 1 Capacitor C matched with receiving end 2 So that the resonance frequency of the transmitting coil and the receiving coil reaches a target value, wherein omega is the resonance frequency; l is the self inductance of the transmitting coil and the receiving coil; and C is the parasitic capacitance value of the transmitting coil and the receiving coil.
Has the beneficial effects that:
the wireless energy transmission system of the invention provides a practicable wireless energy transmission method. The key of the transmission efficiency in the wireless energy transmission system is impedance matching, and if the impedance matching degree of the system is poor, the transmission efficiency is extremely low, and most energy is reflected. The impedance matching method of the invention improves the matching degree and improves the transmission efficiency.
Drawings
Fig. 1 is a schematic system structure diagram of a wireless energy transfer system based on an electromagnetic metamaterial according to an embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a power amplifier of a wireless energy transmission system based on an electromagnetic metamaterial according to an embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a broadband impedance matcher of a wireless energy transmission system based on an electromagnetic metamaterial according to an embodiment of the present invention.
Fig. 4 is a schematic structural diagram of an electromagnetic metamaterial of a wireless energy transfer system based on an electromagnetic metamaterial according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
As shown in fig. 1, the wireless energy transfer system based on the electromagnetic metamaterial of the present invention includes a power output port, a transmitting port, an electromagnetic metamaterial, a receiving port and a load port; the power output port comprises a signal source, a power amplifier and a broadband impedance matcher; the transmitting port comprises a transmitting end matching capacitor C 1 And a transmitting coil; the receiving port comprises a receiving end matching capacitor C 2 And a receiving coil; the load of the load port is a low-voltage bulb; the signal source is connected with the power amplifier in series; the power amplifier is connected with a broadband impedance matcher in series; the broadband impedance matcher is connected with a transmitting port in series; the transmitting terminal is matched with a capacitor C 1 A ground terminal lead connected in series to the transmitting coil; the receiving end matching capacitor C 2 A ground terminal lead connected in series to the receiving coil; the transmitting coil and the receiving coil are separated by the electromagnetic metamaterial, the distance between the transmitting coil and the electromagnetic metamaterial is 10cm, the distance between the receiving coil and the electromagnetic metamaterial is 10-100cm, and energy is transmitted through magnetic induction resonance; the receiving port is connected in series with a load port. The transmitting coil and the receiving coil are separated from each other and transmit energy through magnetic induction resonance;
as shown in fig. 2, the power amplifier of the power output port of the wireless energy transmission system based on the electromagnetic metamaterial of the present invention includes a power amplifier signal output port, a filter and a coupler, and the working mode is that the power amplifier output signal is input into the filter, processed by the filter, the signal enters the power monitoring circuit, and the power is output after being processed by the coupler. The amplifying circuit of the power amplifier adopts an imported high-power RF-MOSFET as a core device, and the power amplifier amplifies step by step, synthesizes multiple paths and outputs the signals through a low-pass filter with a sub-band. The power amplifier operates in class E.
As shown in fig. 3, the broadband impedance matcher at the power output port of the wireless energy transmission system based on the electromagnetic metamaterial is an n-shaped circuit and an adjustable capacitor C 3 Parallel connected with mica capacitor, the main line is adjustable inductor, and the other branch is adjustable capacitor C 4 . Three mica capacitors are externally connected in parallel inside the broadband impedance matcher, and the capacitance values of the mica capacitors are 3000PF, 1500PF and 1500 PF; two adjustable capacitors C 3 、C 4 The impedance matching range of (2-45) omega +/-j (0-70) omega; the coil inductance of the internal adjustable inductor is 100 muh.
As shown in fig. 4, the electromagnetic metamaterial structure of the wireless energy transfer system based on the electromagnetic metamaterial of the present invention is a square coil structure. The side length a of the lattice of the electromagnetic metamaterial unit is 100mm, the maximum side length b of the square spiral coil in the electromagnetic metamaterial unit is 96mm, the width w of a lead in the coil is 0.5mm, the coil turn interval s is 0.5mm, and the number N of the coil turns is 19.
The number of turns of the transmitting coil and the receiving coil is 15 turns, and the turn distance is 0.5 cm; the circumference of the outermost coil is 94.24cm, and the circumference of the innermost coil is 37.71 cm. The signal source provides a sine wave signal with the frequency of 3.5MHz and the power of 13 dBm; the power amplifier adopts an A, B class amplification circuit, and the gain is 31 dB; adjustable capacitor C in said broadband impedance matcher 3 And C 4 Respectively adjusting the return loss amplitude and the resonant frequency value in the system; the transmitting coil and the receiving coil are formed by winding litz wires and adopt a circular structure; the resonance frequency of the electromagnetic metamaterial is 3.5 MHz.
The invention discloses an impedance matching method of a wireless energy transmission system based on an electromagnetic metamaterial, which is based on a frequency resonance formula
Figure BDA0003753871760000041
Measuring self inductance and parasitic capacitance of the transmitting coil and the receiving coil, and matching the transmitting end with a capacitor C 1 Capacitor C matched with receiving end 2 FromSo that the resonant frequency of the transmitting coil and the receiving coil reaches a target value, wherein omega is the resonant frequency; l is the self inductance of the transmitting coil and the receiving coil; and C is the parasitic capacitance value of the transmitting coil and the receiving coil.
Placing an electromagnetic metamaterial in a transmitting coil and a receiving coil, wherein the structural parameters of the electromagnetic metamaterial are as follows: the side length a of the crystal lattice of the electromagnetic metamaterial unit is 100mm, the maximum side length b of the square spiral coil in the electromagnetic metamaterial unit is 96mm, the width w of a lead in the coil is 0.5mm, the coil turn distance s is 0.5mm, and the coil turn number N is 19. And adjusting the relative positions of the electromagnetic metamaterial, the transmitting coil and the receiving coil to obtain different transmission efficiencies. And operating the power amplifier to enable the power amplifier to amplify the output signal of the signal source, adjusting the voltage value of the power amplifier to 5.7V, adjusting the current value to 2.2A and the power gain to 31dB, and normally providing power for the transmitting coil after being adjusted by the broadband impedance matcher. When the position of the electromagnetic metamaterial is adjusted, the equivalent impedance of the system changes. In order to adjust the system equivalent impedance to 50 Ω, the system equivalent impedance is adjusted by using a broadband impedance matcher. And adjusting the mica capacitance value internally connected with the broadband impedance matcher to maximize the transmission efficiency. In order to visually detect the transmission efficiency of the wireless energy transmission system, a low-voltage bulb is used as a load. The rated voltage value of the low-voltage bulb is 5V, and the power is 5W. After the wireless energy transfer system normally operates, the adjustable capacitor C of the broadband impedance matcher is adjusted 3 And C 4 The transmission efficiency of the wireless energy transmission system can be visually detected by observing the brightness of the low-voltage bulb.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (8)

1. A wireless energy transfer system based on electromagnetic metamaterial is characterized in that: the device comprises a power output port, a transmitting port, an electromagnetic metamaterial, a receiving port and a load port; wherein the power output port packetThe system comprises a signal source, a power amplifier and a broadband impedance matcher; the transmitting port comprises a transmitting end matching capacitor C 1 And a transmitting coil; the receiving port comprises a receiving end matching capacitor C 2 And a receiving coil; the load of the load port is a low-voltage bulb; the signal source is connected with the power amplifier in series; the power amplifier is connected with a broadband impedance matcher in series; the broadband impedance matcher is connected with a transmitting port in series; the transmitting terminal is matched with a capacitor C 1 A ground terminal lead connected in series to the transmitting coil; the receiving end matching capacitor C 2 A ground terminal lead connected in series to the receiving coil; the transmitting coil and the receiving coil are separated by electromagnetic metamaterials and transmit energy through magnetic induction resonance; the receiving port is connected in series with a load port.
2. The wireless energy transfer system based on the electromagnetic metamaterial according to claim 1, wherein: the number of turns of the transmitting coil and the receiving coil is 15 turns, and the turn distance is 0.5 cm; the circumference of the outermost coil is 94.24cm, and the circumference of the innermost coil is 37.71 cm.
3. The wireless energy transfer system based on the electromagnetic metamaterial according to claim 1, wherein: the broadband impedance matcher is internally and externally connected with three mica capacitors which are connected in parallel, and the capacitance values of the three mica capacitors are 3000PF, 1500PF and 1500 PF; also comprises an adjustable capacitor C 3 And an adjustable capacitor C 4 The impedance matching range of the two adjustable capacitors is (2-45) omega +/-j (0-70) omega; the coil inductance of the internal adjustable inductor is 100 muh.
4. The wireless energy transfer system based on the electromagnetic metamaterial according to claim 1, wherein: the power amplifier comprises a power amplifier signal output port, a filter and a coupler, wherein a signal output by the power amplifier signal output port is input into the filter, processed by the filter, and enters the coupler of the power monitoring circuit to be processed, and then power is output.
5. The wireless energy transfer system based on the electromagnetic metamaterial according to claim 1, wherein: the rated voltage value of the low-voltage bulb is 5V, and the power of the low-voltage bulb is 5W.
6. The wireless energy transfer system based on the electromagnetic metamaterial according to claim 1, wherein: the side length a of the electromagnetic metamaterial unit lattice of the electromagnetic metamaterial is 100mm, the maximum side length b of the square spiral coil in the electromagnetic metamaterial unit is 96mm, the width w of a lead in the coil is 0.5mm, the coil turn interval s is 0.5mm, and the coil turn number N is 19.
7. The wireless energy transfer system based on the electromagnetic metamaterial according to claim 1, wherein: the distance between the transmitting coil and the electromagnetic metamaterial is 10cm, and the distance between the receiving coil and the electromagnetic metamaterial is 10-100 cm.
8. An impedance matching method of the wireless energy transmission system based on the electromagnetic metamaterial according to any one of claims 1 to 7, wherein: according to the formula of frequency resonance
Figure FDA0003753871750000011
Measuring self inductance and parasitic capacitance of the transmitting coil and the receiving coil, and matching the transmitting end with a capacitor C 1 Capacitor C matched with receiving end 2 So that the resonance frequency of the transmitting coil and the receiving coil reaches a target value, wherein omega is the resonance frequency; l is the self inductance of the transmitting coil and the receiving coil; and C is the parasitic capacitance value of the transmitting coil and the receiving coil.
CN202210848307.1A 2022-07-19 2022-07-19 Wireless energy transfer system based on electromagnetic metamaterial and impedance matching method Pending CN115065174A (en)

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CN202210848307.1A CN115065174A (en) 2022-07-19 2022-07-19 Wireless energy transfer system based on electromagnetic metamaterial and impedance matching method

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