CN211296336U - Multi-load wireless power transmission system with constant power and constant efficiency characteristics - Google Patents
Multi-load wireless power transmission system with constant power and constant efficiency characteristics Download PDFInfo
- Publication number
- CN211296336U CN211296336U CN201922232255.1U CN201922232255U CN211296336U CN 211296336 U CN211296336 U CN 211296336U CN 201922232255 U CN201922232255 U CN 201922232255U CN 211296336 U CN211296336 U CN 211296336U
- Authority
- CN
- China
- Prior art keywords
- receiving
- transmitting
- transmitting side
- constant
- load
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Inverter Devices (AREA)
Abstract
The utility model discloses a multi-load wireless power transmission system with constant power and constant efficiency characteristics, which comprises a transmitting device and at least 2 receiving devices; the transmitting device consists of a direct-current power supply, a full-bridge inverter, a transmitting side resonant capacitor module, a transmitting coil, a current sampling circuit, a zero-crossing comparator and a driver which are sequentially connected, wherein the transmitting side resonant capacitor module comprises a transmitting side switch controller, a transmitting side communication module and at least 2 parallel-connected switch capacitor branches, and each switch capacitor branch is formed by connecting a transmitting side switch and a transmitting side resonant capacitor in series; each receiving device consists of a receiving coil, a receiving side resonance capacitor module and a load which are connected in series, wherein the receiving side resonance capacitor module comprises a receiving side resonance capacitor, a receiving side switch controller and a receiving side communication module which are connected in sequence. The utility model discloses have constant power constant efficiency characteristic, system space degree of freedom is high, the robustness is strong, circuit structure is simple, easily realizes.
Description
Technical Field
The utility model belongs to the technical field of wireless transmission's technique and specifically relates to indicate a many loads wireless transmission system with constant power constant efficiency characteristic.
Background
The wireless power transmission technology directly transmits electric energy to a load through air without wires or other physical connection, has the advantages of flexible and convenient power transmission and the like, and is widely applied to the fields of portable electronic equipment, household appliances, electric automobiles, implanted medical power supplies and the like. For a long time, power supply objects of a wireless power transmission system mostly adopt a single load as a main object, only point-to-point wireless power transmission can be carried out, the utilization rate of the system is low, the spatial freedom degree is low, and the transmission performance of the system is sensitive to the position change of the load. With the increasing number of electric and electronic products with the function of wirelessly receiving electric energy, a single-load wireless power transmission system cannot meet the requirement that multiple devices need to be wirelessly powered at the same time.
The multi-load wireless power transmission system is gradually one of the research hotspots in recent years, and has the advantages of large number of loads, strong practicability and the like. In recent years, various types of multi-load wireless power transmission systems have appeared, and a single-input multi-output type multi-load wireless power transmission system is one of the more widely studied. However, the existing single-input multi-output multi-load wireless power transmission systems all adopt an induction type or resonant type wireless power transmission principle, when the position or direction of a load changes, the output power and the transmission efficiency of each load obviously change, the constant power and constant efficiency output cannot be maintained, the axial moving distance of the load is short, the radial offset range is small, and the spatial degree of freedom is low. In order to improve the spatial degree of freedom, the prior art usually adopts the increase of the area of the transmitting coil, the adoption of a three-dimensional transmitting coil or the addition of an additional compensating circuit, but simultaneously causes the problems of overlarge system volume, increased cost, complex control, reduced reliability and the like.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome prior art's shortcoming and not enough, provide a many loads wireless transmission system with constant power constant efficiency characteristic, make the system realize the constant power constant efficiency output under certain condition, and irrelevant with load position or direction, system space degree of freedom is high, the robustness is strong, and only adopts single transmitting coil, circuit structure is simple, easily realizes.
In order to achieve the above object, the present invention provides a technical solution: a multi-load wireless power transmission system having constant power and constant efficiency characteristics, the system comprising a transmitting device and at least 2 receiving devices; the transmitting device comprises a direct-current power supply, a full-bridge inverter, a transmitting side resonance capacitor module, a transmitting coil, a current sampling circuit, a zero crossing comparator and a driver which are sequentially connected, wherein the driver is connected with the full-bridge inverter, the transmitting side resonance capacitor module comprises a transmitting side switch controller, a transmitting side communication module and at least 2 parallel switch capacitor branches, the number of the switch capacitor branches is consistent with that of the receiving device, each switch capacitor branch is formed by connecting a transmitting side switch and a transmitting side resonance capacitor in series, and the transmitting side switch controller is respectively connected with the transmitting side communication module and the parallel switch capacitor branches to control the on and off of each transmitting side switch; each receiving device consists of a receiving coil, a receiving side resonance capacitor module and a load which are connected in series, wherein the receiving side resonance capacitor module comprises a receiving side resonance capacitor, a receiving side switch controller and a receiving side communication module which are connected in sequence, and the receiving side switch controller controls the on and off of the receiving side switch; the receiving side communication module sends load access conditions and electric quantity demand information of the accessed load to the transmitting side communication module, the transmitting side switch controller controls the on and off of the transmitting side switches and the working time of the transmitting side switches according to the information received by the transmitting side communication module, and only one transmitting side switch is in an on state at any moment.
Further, the transmitting coil and the receiving coil are the same in shape and size.
Further, the receiving means have different natural resonant frequencies, i.e.
Are different from each other, whereini0At a natural resonant frequency, LiInductance value for the receiving coil, CLiFor the reception-side resonant capacitance value, i is 1,2, … …, n.
Furthermore, the phase difference between the output voltage of the full-bridge inverter and the loop current at the transmitting side is 180 degrees, and V is satisfiedin＝-RNIinEquivalent to a resistance value of-RNAnd because of adopting the current sampling circuit and the zero crossing comparator to generate the driving signal of the full bridge inverter, -RNCan be automatically adjusted in the formula VinIs the output voltage of a full bridge inverter, IinIs the transmit side loop current.
Further, the system needs to satisfy the following conditions:
in the formula, ωTi、ωi0The natural resonance angular frequency of the ith transmitting side resonance capacitor and the natural resonance angular frequency of the ith receiving device are selected respectively
LTAnd CiRespectively, the inductance value of the transmitting coil and the resonance capacitance value of the transmitting side, LiAnd CLiThe inductance value of a receiving coil and the resonance capacitance value of a receiving side of the ith receiving device are respectively; -RNAnd rTAre respectively a DC power supply VdcThe equivalent resistance value and the equivalent internal resistance of the transmitting side loop are converted by the full-bridge inverter; rLiAnd rLiRespectively the load resistance value of the ith receiving device and the equivalent internal resistance of a receiving side loop; k is a radical ofiIs the coupling coefficient of the receiving coil and the transmitting coil of the ith receiving device, and
wherein M isiThe mutual inductance value of the receiving coil and the transmitting coil is 1,2, … …, n.
Further, a critical coupling coefficient k of the ith receiving device is definedciComprises the following steps:
when the ith receiving device is at kci≤kiIn the region < 1, the operating frequency f of the loadiI.e. the switching frequency of the full bridge inverter, can be varied with the coupling factor kiThe change is automatically adjusted, and the following conditions are met:
in the formula, ωi0Is the natural resonant angular frequency of the i-th receiving device, and
Lithe inductance value of the receiving coil of the ith receiving device; rLiAnd rLiRespectively the load resistance value of the ith receiving device and the equivalent internal resistance of a receiving side loop; k is a radical ofiIs the coupling coefficient of the receiving coil and the transmitting coil of the ith receiving device, and
wherein M isiThe mutual inductance value of the receiving coil and the transmitting coil is 1,2, … …, n.
Compared with the prior art, the utility model, have following advantage and beneficial effect:
1. the utility model discloses only adopt single transmitting coil to realize many loads wireless power supply, simple structure, emitter is small.
2. The utility model discloses can keep constant power, constant efficiency output when load position or direction change, improve many loads wireless transmission system's spatial degree of freedom, the system robustness is strong.
3. The utility model discloses can insert the condition and every load actual power consumption demand according to the load, through control transmission side switch closure or turn-off, realize giving certain load power supply, be applicable to the changeable occasion of load, effectively improve many loads wireless transmission system's practicality.
Drawings
Fig. 1 is a schematic structural diagram of the system of the present invention.
Fig. 2 is an equivalent circuit diagram of the system of the present invention at two loads.
FIG. 3 shows the output voltage V of the full bridge inverter of the system of the present inventioninAnd the loop current I of the transmitting sideinSimulated waveform diagrams of the relationships.
Fig. 4 is a timing diagram of the system of the present invention for the transmitting side switch when two loads are applied.
Fig. 5 is a diagram of the theory and simulation of the curve of the working frequency of the two loads of the system according to the present invention along with the variation of the coupling coefficient.
Fig. 6 is a graph showing the output power and transmission efficiency of two loads of the system according to the present invention, which is a theoretical and simulated graph of the curve of the variation of the coupling coefficient.
Detailed Description
The present invention will be further described with reference to the following specific embodiments.
As shown in fig. 1, the multi-load wireless power transmission system with constant power and constant efficiency provided by this embodiment includes a transmitting device and at least 2 receiving devices; the transmitting device is composed of sequentially connected direct current power supplies VdcFull-bridge inverter 01, transmitting side resonant capacitor module 02 and transmitting coil LTThe drive 05 is connected with the full-bridge inverter 01, wherein the transmitting side resonance capacitor module comprises a transmitting side switch controller 021, a transmitting side communication module 022 and at least 2 parallel switch capacitor branches, the number of the switch capacitor branches is consistent with that of the receiving device, and each switch capacitor branch is formed by a transmitting side switch SiAnd a transmitting side resonance capacitor CiThe transmitting side switch controller 021 is respectively connected with the transmitting side communication module 022 and the n parallel-connected switched capacitorsBranch circuits are connected to control each transmitting side switch SiTurn on and turn off; each receiving device is composed of receiving coils L connected in seriesiReceiving side resonant capacitor module 06 and load RLiThe receiving side resonance capacitor module comprises a receiving side resonance capacitor C connected in sequenceLiReception side switch HiA receiving side switch controller 061 and a receiving side communication module 062, the receiving side switch controller 061 controls the receiving side switch HiTurn on and turn off; the receiving-side communication module 062 transmits the payload R to the transmitting-side communication module 022LiAccess situation and access load RLiThe transmitting side switch controller 021 controls the transmitting side switch S according to the information received by the transmitting side communication module 022iOn and off and its operating time deltatiAnd only one transmitting side switch S at any one timeiIn the on state; the transmitting coil LTAnd a receiving coil LiIs the same in shape and size; wherein i is 1,2, … …, n.
In the following we will describe the above system in more detail with two loads as an example. In the embodiment, a transmitting side and a receiving side both adopt a coil and resonant capacitor series connection structure to form an SS type topology, two receiving devices have different natural resonant frequencies, and system parameters are set as follows: DC input voltage VdcThe natural resonant frequency and the load size of the first receiving device are 300kHz and R, respectively, 50VL1The natural resonant frequency and the load of the second receiving device are 100kHz and R, respectively, 10 ΩL2The equivalent circuit of the double-load system is shown in fig. 2, wherein-R is equal to 15 ΩNFor a DC power supply VdcEquivalent resistance value r after conversion by full-bridge inverterTIs the equivalent internal resistance of the transmitting-side loop, LTIs a transmitting coil inductance, C1,2Is a transmission side resonance capacitance; l isiTo the inductance value of the receiving coil i, CLiFor the receiving side resonant capacitance, RLiAnd rLiRespectively the load equivalent resistance value and the receiving side loop equivalent internal resistance of the ith receiving device; miFor the receiving coil i and the transmitting coil LTMutual inductance (i ═ i-1,2)。
Output voltage V of full bridge inverterinAnd a transmitting side loop current IinThe phase difference is 180 degrees, and V is satisfiedin＝-RNIinThe simulation waveform is shown in FIG. 3, which is equivalent to a resistance value of-R in FIG. 2NAnd because of adopting the current sampling circuit and the zero crossing comparator to generate the driving signal of the full bridge inverter, -RNCan be automatically adjusted.
At the transmitting side switch SiWhen the power supply is switched on, the transmitting device only transmits energy to the ith receiving device, and the influence of the rest receiving devices can be ignored. According to the equivalent circuit shown in fig. 2 and kirchhoff's voltage law, the following system of state equations can be obtained:
in the formula, -RNFor a DC power supply VdcEquivalent resistance value r after conversion by full-bridge inverterTIs the equivalent internal resistance of the transmitting-side loop, LTIs a transmitting coil inductance; omega is the angular frequency of system operation, omegaTiAnd ωi0Selecting ith resonance capacitor C for transmitting sideiNatural angular frequency of time and natural angular frequency of resonance of the i-th receiving device, and ωTi＝ωi0；RLiAnd rLiRespectively the load equivalent resistance value and the receiving side loop equivalent internal resistance of the ith receiving device; l isiIs the inductance value of the receiving coil i;
and
respectively a transmitting coil loop and a receiving coil loop current vector; k is a radical ofiThe coupling coefficient of the receiving coil and the transmitting coil of the ith receiving device is satisfied
Wherein M isiIs a receiving coil LiAnd a transmitting coil LTThe mutual inductance value (i ═ 1, 2).
The condition that formula (1) has a non-zero solution is:
the transmitting device and the receiving device should satisfy the following conditions:
from equations (2) and (3), the steady-state frequency solution of the system can be obtained as:
the condition that a pure real solution of the frequency can be obtained from equation (4) is:
the conditions that the coupling coefficient and the load of the system need to satisfy are further obtained from equation (5) as follows:
the output power P of the i-th receiving device at this time can be obtained from the equations (1) to (3)oiAnd transmission efficiency ηiComprises the following steps:
in the multi-load wireless power transmission system with the constant power and constant efficiency characteristic, the receiving side communication module sends load access condition information and electric quantity demand information of an access load to the transmitting side communication module, and the transmitting side switch controller controls the transmitting side switch S according to the information received by the transmitting side communication module1And S2Is turned on and off and the working time is respectively set to be delta T1、ΔT2And only one transmitting side switch S at any one timeiIs in an on state. Shown in FIG. 4 as switch S1And S2In the figure, "1" indicates high level, switch SiON, '0' indicating low level, switch SiTurn off (i ═ 1, 2).
From equation (6), a critical coupling coefficient k of the i-th receiving apparatus is definedciComprises the following steps:
when the ith receiving device is at kci≤kiIn the region < 1, the operating frequency f of the load i is determined according to equation (4)iI.e. the switching frequency of the transmitting-side inverter, there are two branches which can follow the coupling coefficient kiAutomatically adjusts for the change in the amount of time. The operating frequencies f of the two loads are shown in FIG. 5iCoefficient of random coupling kiThe graph shows that the two loads have working frequencies f and the theoretical and simulation results are consistentiCan follow k in the above-mentioned regioniThe change of (2) is automatically adjusted.
As can be seen from equations (8) to (9), the dual-load wireless power transmission system of this example has a switch S on the transmission sideiClosed and operating at kci≤kiWhen the area is less than 1, the load i can keep constant power and constant efficiency transmission and is not changed along with the change of the coupling coefficient. As shown in fig. 6, which is a graph of the output power and transmission efficiency of two loads according to the variation of the coupling coefficient, the left side is a load 1, and the right side is a load 2, it can be seen that the theory and simulation are consistent, and the coupling coefficient k isiDuring a wide range of variationThe output power and the transmission efficiency of the two loads are kept constant, the spatial degree of freedom of the system is effectively improved, and the method has higher practical application value.
The above-mentioned embodiments are only preferred embodiments of the present invention, and the scope of the present invention is not limited thereto, so that all the changes made according to the shape and principle of the present invention should be covered within the protection scope of the present invention.
Claims (4)
1. A multi-load wireless power transmission system with constant power and constant efficiency characteristics is characterized in that: the system comprises a transmitting device and at least 2 receiving devices; the transmitting device comprises a direct-current power supply, a full-bridge inverter, a transmitting side resonance capacitor module, a transmitting coil, a current sampling circuit, a zero crossing comparator and a driver which are sequentially connected, wherein the driver is connected with the full-bridge inverter, the transmitting side resonance capacitor module comprises a transmitting side switch controller, a transmitting side communication module and at least 2 parallel switch capacitor branches, the number of the switch capacitor branches is consistent with that of the receiving device, each switch capacitor branch is formed by connecting a transmitting side switch and a transmitting side resonance capacitor in series, and the transmitting side switch controller is respectively connected with the transmitting side communication module and the parallel switch capacitor branches to control the on and off of each transmitting side switch; each receiving device consists of a receiving coil, a receiving side resonance capacitor module and a load which are connected in series, wherein the receiving side resonance capacitor module comprises a receiving side resonance capacitor, a receiving side switch controller and a receiving side communication module which are connected in sequence, and the receiving side switch controller controls the on and off of the receiving side switch; the receiving side communication module sends load access conditions and electric quantity demand information of the accessed load to the transmitting side communication module, the transmitting side switch controller controls the on and off of the transmitting side switches and the working time of the transmitting side switches according to the information received by the transmitting side communication module, and only one transmitting side switch is in an on state at any moment.
2. The multi-load wireless power transmission system with constant power and constant efficiency characteristics as claimed in claim 1, wherein said transmitting coil and receiving coil are identical in shape and size.
3. The multi-load wireless power transmission system with constant-power and constant-efficiency characteristics according to claim 1, wherein: the receiving means having different natural resonant frequencies, i.e.
Are different from each other, whereini0At a natural resonant frequency, LiInductance value for the receiving coil, CLiFor the reception-side resonant capacitance value, i is 1,2, … …, n.
4. The multi-load wireless power transmission system with constant-power and constant-efficiency characteristics according to claim 1, wherein: the phase difference between the output voltage of the full-bridge inverter and the loop current of the transmitting side is 180 degrees, and V is satisfiedin＝-RNIinEquivalent to a resistance value of-RNAnd because of adopting the current sampling circuit and the zero crossing comparator to generate the driving signal of the full bridge inverter, -RNCan be automatically adjusted in the formula VinIs the output voltage of a full bridge inverter, IinIs the transmit side loop current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922232255.1U CN211296336U (en) | 2019-12-13 | 2019-12-13 | Multi-load wireless power transmission system with constant power and constant efficiency characteristics |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922232255.1U CN211296336U (en) | 2019-12-13 | 2019-12-13 | Multi-load wireless power transmission system with constant power and constant efficiency characteristics |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN211296336U true CN211296336U (en) | 2020-08-18 |
Family
ID=72017204
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201922232255.1U Active CN211296336U (en) | 2019-12-13 | 2019-12-13 | Multi-load wireless power transmission system with constant power and constant efficiency characteristics |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN211296336U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110943551A (en) * | 2019-12-13 | 2020-03-31 | 华南理工大学 | Multi-load wireless power transmission system with constant power and constant efficiency characteristics |
-
2019
- 2019-12-13 CN CN201922232255.1U patent/CN211296336U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110943551A (en) * | 2019-12-13 | 2020-03-31 | 华南理工大学 | Multi-load wireless power transmission system with constant power and constant efficiency characteristics |
| CN110943551B (en) * | 2019-12-13 | 2024-07-12 | 华南理工大学 | Multi-load wireless power transmission system with constant power and constant efficiency characteristics |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110943551B (en) | Multi-load wireless power transmission system with constant power and constant efficiency characteristics | |
| CN109130903B (en) | Low-voltage high-power wireless charging system with bilateral LCCL-T topology | |
| CN108767956B (en) | Dynamic wireless power transmission system and passive control method thereof | |
| CN102882286B (en) | Electric field coupling-based wireless power transmission system | |
| CN109302070A (en) | Power converter circuit topological structure and its control method | |
| CN104901429A (en) | Magnetic coupling resonant wireless energy transmission receiving circuit | |
| CN104079079A (en) | Resonance type non-contact power supply device, integrated circuit and constant voltage control method | |
| CN102771041A (en) | Three-quarter bridge power converters for wireless power transfer applications and other applications | |
| CN101013860A (en) | Charging equipment for high-voltage pulse capacitor | |
| CN106685242B (en) | Single-stage AC to DC converter | |
| Fnato et al. | Wireless power distribution with capacitive coupling excited by switched mode active negative capacitor | |
| CN108656994A (en) | A kind of electric vehicle IPT systems of variable capacitance | |
| US11489452B2 (en) | Bridgeless single-stage single-inductor multiple-output (SIMO) AC-AC converter topology | |
| CN103346624B (en) | The multi-load wireless energy transform device that can automatically control | |
| CN206775244U (en) | Magnetic coupling series, parallel formula radio energy power transfering device | |
| CN214112341U (en) | Battery energy processing device and vehicle | |
| CN108718106A (en) | A kind of wireless charging system for electric vehicle | |
| Dou et al. | Investigation and design of wireless power transfer system for autonomous underwater vehicle | |
| CN211296336U (en) | Multi-load wireless power transmission system with constant power and constant efficiency characteristics | |
| CN104716747B (en) | Wireless charging system and its control method | |
| CN214255869U (en) | Relay coil type multi-load wireless power transmission system with constant output characteristic | |
| CN104682712A (en) | SCC (single-channel controller) structure applied to current source type LCL (lower control limit) high-frequency resonant converter | |
| CN109314406B (en) | Wireless power transmission system | |
| CN106532977A (en) | Control device based on wireless power transmission system and wireless power transmission system | |
| Baharom et al. | Grid to Vehicle Wireless Power Transfer using Single Phase Matrix Converter (SPMC) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |