A wireless energy transfer system and method

Abstract

The present application relates to a kind of wireless energy transmission systems and methods, system includes transmitting module and receiving module, the transmitting module includes control unit and multiple transmitting units connected with the control unit, the control unit controls at least one transmitting unit close to the receiving module in energy emission state, so that the transmitting unit and the receiving module carry out wireless energy transmission, the control unit controls the remaining transmitting units are all in energy local state, each transmitting unit is switched according to whether close to receiving module energy emission state and energy local state.The present application enables receiving module to find the transmitting unit of transmission position optimum compared with prior art, and ensure that transmitting unit is always in resonance mode, can carry out high-speed dynamic wireless transmission.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wireless energy transmission, and in particular to a wireless energy transmission system and method. BACKGROUND

[0002] In 2007, Massachusetts Institute of Technology first proposed a magnetic resonance type wireless energy transmission system, which overcomes the shortcoming of short transmission distance of the previous inductive type wireless energy transmission system, realizes a high ratio of transmission distance to diameter, and exhibits the advantages of magnetic resonance type transmission. In a dynamic wireless transmission system, not only the efficiency of the transmission direction needs to be ensured, but also the continuous energy transmission needs to be met. Since the position of the receiving end also moves in the area perpendicular to the transmission direction, the position of the transmitting end needs to be changed according to the position of the receiving end, so that the receiving end and the transmitting end are in the best transmission position, i.e. the receiving end and the transmitting end are aligned, thereby meeting the continuous energy transmission.

[0003] The prior art moves the transmitting end or the receiving end by using a positioning device to keep the transmitting end and the receiving end of the system aligned to solve the above problems. However, the following problems still exist:

[0004] (1) The prior art needs to move the position of the transmitting end or the receiving end to find the best transmission position, which requires the addition of some additional transmission devices, increasing the complexity of the system;

[0005] (2) The transmitting end of the prior art is in a closed state, there is no resonance mode, and the transmitting end does not retain energy. When recharging, it is necessary to re-establish the resonance mode; it is necessary to increase the response time of the system, which is not conducive to high-speed dynamic wireless transmission;

[0006] (3) The characteristic impedance of the conventional transmitting end in the on / off state is inconsistent. Therefore, after the transmitting end is connected in series or parallel, the resonance mode of the system will be split, and the best working frequency will be related to the networking form and the on / off state of the transmitting unit. Such a network cannot perform fixed frequency transmission. SUMMARY

[0007] The purpose of the present application is to overcome the defects of the prior art and provide a wireless energy transmission system that enables the receiving module to find the transmitting unit with the best transmission position and ensures that the transmitting unit is always in resonance mode, enabling high-speed dynamic wireless transmission.

[0008] The purpose of the present application can be achieved by the following technical solutions:

[0009] According to one aspect of the present application, the present application provides a wireless energy transmission system, comprising a transmitting module and a receiving module, the transmitting module comprising a control unit and a plurality of transmitting units connected to the control unit, the control unit controls at least one transmitting unit close to the receiving module to be in an energy transmission state, so that the transmitting unit and the receiving module perform wireless energy transmission, and the control unit controls the remaining transmitting units to be in an energy local state.

[0010] Each of the transmitting units switches between the energy transmission state and the energy local state according to whether it is close to the receiving module.

[0011] Preferably, each of the transmitting units comprises a mode switch, a lumped inductor, a transmitting coil and a resonance capacitor, the stationary end of the mode switch is connected to the control unit, and the lumped inductor and the transmitting coil are both connected to the resonance capacitor.

[0012] When the transmitting unit is in the energy local state, the movable end of the mode switch is connected to the lumped inductor, and the lumped inductor resonates with the resonance capacitor.

[0013] When the transmitting unit is in the energy transmission state, the movable end of the mode switch is connected to the transmitting coil and the resonance capacitor.

[0014] Preferably, the inductance value of the transmitting coil is equal to the inductance value of the lumped inductor.

[0015] Preferably, a first intrinsic loss resistor is provided between the lumped inductor and the resonance capacitor, and a second intrinsic loss resistor is provided between the transmitting coil and the resonance capacitor.

[0016] Preferably, the resistance value of the first intrinsic loss resistor is equal to the resistance value of the second intrinsic loss resistor.

[0017] According to another aspect of the present application, the present application provides a wireless energy transmission method applied to the wireless energy transmission system according to any one of the above, comprising the following steps:

[0018] S1: setting a first period and a second period, and controlling the transmitting units to be in an energy local state and an energy transmission state in the corresponding periods respectively;

[0019] S2: judging whether there is a receiving module close to the transmitting units, if not, keeping the transmitting units in the energy local state and the energy transmission state in the corresponding periods respectively, otherwise performing S3;

[0020] S3: controlling the transmitting units close to the receiving module to be in the energy transmission state, and controlling the remaining transmitting units to be in the energy local state;

[0021] S4: judging whether there is a transmitting unit close to the receiving module, if yes, executing S3, otherwise executing S1.

[0022] Preferably, the input current of the transmitting unit is detected to judge whether there is a receiving module close to the transmitting unit;

[0023] When the input current of the transmitting unit is higher than the set threshold, the receiving module is close to the transmitting unit; when the input current of the transmitting unit is lower than the set threshold, the receiving module is away from the transmitting unit.

[0024] Compared with the prior art, the present application has the following advantages:

[0025] 1. The wireless energy transmission system provided by the present application controls the closest transmitting unit to be in an energy transmitting state, so that the transmitting unit and the receiving module perform wireless energy transmission, and the control unit controls the remaining transmitting units to be in an energy local state, so that the receiving module can find the transmitting unit with the best transmission position, and meanwhile, the energy of the remaining transmitting units does not affect the energy reception of the receiving module, avoiding the complexity of adding an additional transmission device in the prior art.

[0026] 2. The wireless energy transmission system provided by the present application ensures that the transmitting unit is always in a resonance mode by setting the transmitting coil and the lumped inductance with the same inductance value, avoiding the problem of increasing the response time of the system in the prior art to re-establish the resonance mode.

[0027] 3. The wireless energy transmission system provided by the present application realizes magnetic field state control by switching the lumped inductance and the transmitting coil, and the inductance values of the transmitting coil and the lumped inductance are the same, so that the characteristic impedance of the wireless energy transmission system is consistent, avoiding the problem that the transmitting module cannot perform fixed frequency transmission due to the inconsistent characteristic impedance in the on / off state in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The structure schematic diagram of the wireless energy transmission system provided by the present embodiment.

[0029] Figure 2 The structure schematic diagram of the transmitting unit in the embodiment shown in the figure. Figure 1

[0030] The model schematic diagram of the transmitting unit in the embodiment shown in the figure. Figure 3 Figure 1 The magnetic field distribution schematic diagram of the transmitting unit in the energy transmission state of the embodiment shown in the figure.

[0031] Figure 4 Figure 1 The magnetic field distribution schematic diagram of the transmitting unit in the energy transmission state of the embodiment shown in the figure.

[0032] ​​Figure 5 for Figure 1 A schematic diagram of the magnetic field distribution of the transmitting unit in the embodiment shown, where the energy is localized.

[0033] Explanation of markings in the diagram:

[0034] 1. Mode switch; 21. Lumped inductor; 22. Transmitting coil; 31. First intrinsic loss resistor; 32. Second intrinsic loss resistor; 4. Resonant capacitor. Detailed Implementation

[0035] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0036] Example

[0037] refer to Figure 1 As shown, according to one aspect of the present invention, this embodiment provides a wireless power transmission system, including a transmitting module and a receiving module. The transmitting module includes a control unit and a plurality of transmitting units connected to the control unit. The control unit controls at least one transmitting unit close to the receiving module to be in an energy transmitting state, so that the transmitting unit performs wireless power transmission with the receiving module. The control unit controls the remaining transmitting units to be in an energy localization state, so that the energy of the remaining transmitting units is localized within themselves.

[0038] refer to Figure 2 and Figure 3 As shown, each transmitting unit includes a mode switch 1, a lumped inductor 21, a transmitting coil 22, and a resonant capacitor 4. The stationary terminal of the mode switch 1 is connected to the control unit, and the lumped inductor 21 and the transmitting coil 22 are both connected to the resonant capacitor 4.

[0039] refer to Figure 5 As shown, when the moving end of mode switch 1 is connected to lumped inductor 21, lumped inductor 21 resonates with resonant capacitor 4, and the transmitting unit is in a localized energy state, that is, the energy of the transmitting unit is localized in resonant capacitor 4 and lumped inductor 21, and it does not transmit energy to the receiving module.

[0040] refer to Figure 4 As shown, when the moving end of the mode switch 1 is connected to the transmitting coil 22, the transmitting coil 22 resonates with the resonant capacitor 4 and generates a magnetic field around the transmitting coil 22. The transmitting unit is in an energy transmitting state and then transmits energy to the receiving module.

[0041] Preferably, the inductance L1 of the transmitting coil 22 is equal to the inductance L2 of the lumped inductance 21. Let L = L1 = L2, and the system operating frequency is the resonant frequency.

[0042]

[0043] Wherein, ω is the resonance frequency, L is the inductance value of the lumped inductance / transmitting coil, and C is the capacitance value of the resonance capacitor.

[0044] As an optional implementation, a first intrinsic loss resistor 31 is arranged between the lumped inductance 21 and the resonance capacitor 4, and a second intrinsic loss resistor 32 is arranged between the transmitting coil 22 and the resonance capacitor 4.

[0045] Preferably, the resistance value r1 of the first intrinsic loss resistor 31 is equal to the resistance value r2 of the second intrinsic loss resistor 32, i.e., r1=r2=r.

[0046] According to Kirchhoff's law, we can obtain the Kirchhoff equation of the transmitting unit in the energy localization state and the energy transmitting state:

[0047]

[0048] Wherein, U is the input voltage across the transmitting unit; I1 is the current of the transmitting unit; L is the inductance value of the lumped inductance / transmitting coil; C is the resonance capacitor value; and r is the resistance value of the first intrinsic loss resistor / second intrinsic loss resistor.

[0049] When the transmitting unit is in the energy localization state, the energy stored in the transmitting unit is:

[0050]

[0051] Wherein, u c is the voltage across the resonance capacitor.

[0052] The intrinsic loss power is:

[0053]

[0054] Wherein, P r is the intrinsic loss power.

[0055] Preferably, the wireless energy transmission system provided by the present application is more suitable for a large transmitting module and a small receiving module. After the present application is adopted, the transmitting unit closest to the receiving module will be switched to the energy transmitting state, and the remaining transmitting units are in the energy localization state, so that the other parts of the transmitting module will not radiate outward.

[0056] The working principle of the wireless energy transmission system provided by the present application is shown as follows:

[0057] After the single transmitting unit is turned on, the wireless energy transmission system is in standby state, the mode switch 1 adopts bubble switching working mode, that is, the control unit controls the transmitting unit to be in energy local state in the first period T1 and to be in energy transmitting state in the second period T2, the control unit detects and judges whether there is receiving module close to the transmitting unit according to the input current of the transmitting unit, if not, the input current of the transmitting unit keeps in a lower value, the wireless energy transmission system is always in standby state, and the control unit controls the mode switch 1 of each transmitting unit to bubble switch.

[0058] When the receiving module is close to the transmitting unit, the mode switch 1 of the transmitting unit connects the transmitting coil 22 into the system, because the receiving module obtains energy, the equivalent impedance is reduced, the input current of the transmitting unit is increased and reaches the set threshold value; at this time, the mode switch 1 of the transmitting unit keeps connecting the transmitting coil 22 into the system, the transmitting unit is in energy transmitting state, the wireless energy transmission is carried out between the transmitting unit and the receiving module, and the wireless energy transmission system is in working state.

[0059] When the receiving module is far away from the transmitting unit, because the equivalent impedance of the transmitting unit is increased, the input current of the transmitting unit is decreased and is less than the set threshold value, the mode switch 1 of the transmitting unit connects the lumped inductance 22 into the system to close the input, if there is no transmitting unit close to the receiving module, the wireless energy transmission system returns to standby state, and the mode switch 1 adopts bubble switching working mode.

[0060] According to another aspect of the present application, the embodiment provides a wireless energy transmission method applying the wireless energy transmission system as any one of the above, comprising the following steps:

[0061] S1: setting the first period and the second period, and controlling the transmitting unit to be in energy local state and energy transmitting state respectively in the corresponding period;

[0062] S2: judging whether there is receiving module close to the transmitting unit, if not, keeping the transmitting unit in energy local state and energy transmitting state respectively in the corresponding period, otherwise, executing S3;

[0063] S3: controlling the transmitting unit close to the receiving module to be in energy transmitting state, and controlling the remaining transmitting units to be in energy local state;

[0064] S4: judging whether there is transmitting unit close to the receiving module, if yes, executing S3, otherwise, executing S1.

[0065] As an optional implementation, the input current of the transmitting unit is detected and judged whether there is receiving module close to the transmitting unit.

[0066] Specifically, when the input current of the transmitting unit is higher than a set threshold, the receiving module is close to the transmitting unit; when the input current of the transmitting unit is lower than the set threshold, the receiving module is away from the transmitting unit.

[0067] The preferred embodiments of the present application are described in detail above. It should be understood that those of ordinary skill in the art can make modifications and variations without departing from the concept of the present application. Therefore, the technical solutions obtained by logical analysis, reasoning or limited experiments based on the prior art according to the concept of the present application should be within the scope of protection defined by the claims.

Claims

1. A wireless energy transfer system comprising a transmitting module and a receiving module, characterized in that, The transmitting module comprises a control unit and a plurality of transmitting units connected with the control unit, the control unit controls at least one transmitting unit close to the receiving module to be in an energy transmitting state, so that the transmitting unit and the receiving module perform wireless energy transmission, and the control unit controls the rest of the transmitting units to be in an energy local state; Each transmitting unit switches between the energy transmitting state and the energy local state according to whether it is close to the receiving module; Each transmitting unit comprises a mode switch (1), a lumped inductor (21), a transmitting coil (22) and a resonance capacitor (4), the fixed end of the mode switch (1) is connected with the control unit, and the lumped inductor (21) and the transmitting coil (22) are both connected with the resonance capacitor (4); When the transmitting unit is in the energy local state, the movable end of the mode switch (1) is connected with the lumped inductor (21), and the lumped inductor (21) resonates with the resonance capacitor (4); When the transmitting unit is in the energy transmitting state, the movable end of the mode switch (1) is connected with the transmitting coil (22), and the transmitting coil (22) resonates with the resonance capacitor (4).

2. A wireless energy transfer system according to claim 1, wherein, The inductance value of the transmitting coil (22) is equal to the inductance value of the lumped inductor (21).

3. A wireless energy transfer system according to 1, wherein, A first intrinsic loss resistor (31) is arranged between the lumped inductor (21) and the resonance capacitor (4), and a second intrinsic loss resistor (32) is arranged between the transmitting coil (22) and the resonance capacitor (4).

4. A wireless energy transfer system according to Claim 3, wherein, The resistance value of the first intrinsic loss resistor (31) is equal to the resistance value of the second intrinsic loss resistor (32).

5. A wireless energy transmission method applying the wireless energy transmission system according to any one of claims 1 to 4, characterized by, The method comprises the following steps: S1: setting a first period and a second period, and controlling the transmitting units to be in an energy local state and an energy transmitting state in the corresponding periods, respectively; S2: judging whether there is a receiving module close to the transmitting unit, if not, keeping the transmitting units in the energy local state and the energy transmitting state in the corresponding periods, respectively, otherwise, performing S3; S3: controlling the transmitting unit close to the receiving module to be in the energy transmitting state, and controlling the rest of the transmitting units to be in the energy local state; S4: judging whether there is a transmitting unit close to the receiving module, if yes, performing S3, otherwise, performing S1.

6. A wireless energy transfer method according to 5, wherein, Detecting and judging whether there is a receiving module close to the transmitting unit according to the input current of the transmitting unit; When the input current of the transmitting unit is higher than a set threshold, the receiving module is close to the transmitting unit; when the input current of the transmitting unit is lower than the set threshold, the receiving module is away from the transmitting unit.

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