Non-intrusive magnetic field energy collection device capable of self-adapting to magnetic field fluctuation

Abstract

The invention provides a non-intrusive magnetic field energy collection device capable of self-adapting to magnetic field fluctuation, and belongs to the technical field of magnetic energy collection, the device comprises a magnetic energy collection module, a compensation module, a rectifier bridge and a magnetic field fluctuation self-adjusting module, and the compensation module comprises a first capacitor, a first relay, a second capacitor and a second relay; dividing voltage is generated according to the direct current output voltage through a magnetic field fluctuation self-adjusting module, and the dividing voltage is compared with preset reference voltage; when the divided voltage is larger than the reference voltage, the first relay and the second relay are disconnected, the first capacitor is connected in series with the magnetic energy collection module, and the second capacitor is disconnected. And when the divided voltage is not greater than the reference voltage, the first relay and the second relay are conducted, the first capacitor is short-circuited, and the second capacitor and the magnetic energy collection module are connected in parallel, so that the defect that an existing non-intrusive magnetic field energy collection device cannot adapt to wide-range fluctuation of a magnetic field is overcome.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic energy collection, and particularly relates to a non-invasive magnetic field energy collection device capable of self-adapting to magnetic field fluctuation. BACKGROUND

[0002] The non-invasive magnetic field energy collection device has become a promising technology for solving the power supply problem of power system sensors due to its flexible installation, extensive energy sources, and immunity to weather, etc. However, due to the difference in the operation state of the power system, the environmental magnetic field strength may fluctuate in a wide range in the actual working condition, which will lead to unstable working state of the non-invasive magnetic field energy collection device, and the following two problems will occur: first, when the magnetic field strength is weak, the output power and voltage are too low to start the overall device normally; second, when the magnetic field strength is strong, the output power and voltage are too high to cause damage to the collector circuit elements in the system.

[0003] In the prior art, the control parameters of the corresponding circuit are usually adjusted according to the specific value of the external magnetic field strength. However, in the actual application scenario, the external magnetic field strength is in a state of continuous fluctuation and is difficult to detect, which leads to the difficulty of the prior art in realizing accurate control of the control parameters in the actual working condition. Therefore, the existing non-invasive magnetic field energy collection device still has the defect of being unable to self-adapt to wide-range fluctuation of the magnetic field. SUMMARY

[0004] The present application provides a non-invasive magnetic field energy collection device capable of self-adapting to magnetic field fluctuation, which can overcome the defect of the existing non-invasive magnetic field energy collection device being unable to self-adapt to wide-range fluctuation of the magnetic field.

[0005] An embodiment of the present application provides a non-invasive magnetic field energy collection device self-adapting to magnetic field fluctuation, comprising a non-invasive magnetic energy collection module, a compensation module, a rectifier bridge and a magnetic field fluctuation self-adjusting module; wherein the compensation module comprises a first capacitor, a first relay, a second capacitor and a second relay; a first end of the first capacitor is connected with a positive pole of the magnetic energy collection module, a second end of the first capacitor is connected with a first alternating current input end of the rectifier bridge, a first output end of the first relay is connected with the first end of the first capacitor, a second output end of the first relay is connected with the second end of the first capacitor, a first end of the second capacitor is connected with the second end of the first capacitor, a second end of the second capacitor is connected with a first output end of the second relay, a second output end of the second relay is connected with a negative pole of the magnetic energy collection module and a second alternating current input end of the rectifier bridge respectively; a positive pole input end of the first relay is connected with a positive pole input end of the second relay, the positive pole input end of the second relay is connected with a positive pole output end of the magnetic field fluctuation self-adjusting module; a negative pole input end of the first relay is connected with a negative pole input end of the second relay, the negative pole input end of the second relay is connected with a signal output end of the magnetic field fluctuation self-adjusting module;

[0006] The magnetic energy collection module is used for generating an alternating current induction voltage by inducting an external magnetic field;

[0007] The compensation module is used for converting the alternating current induction voltage into an alternating current input voltage;

[0008] The rectifier bridge is used for converting the alternating current input voltage into a direct current output voltage;

[0009] The magnetic field fluctuation self-adjusting module is used for generating a voltage division voltage according to the direct current output voltage, comparing the voltage division voltage with a preset reference voltage, disconnecting the first relay and the second relay when the voltage division voltage is greater than the reference voltage, and turning on the first relay and the second relay when the voltage division voltage is less than the reference voltage.

[0010] Further, the magnetic energy collection module comprises a magnetic core and an induction coil.

[0011] Further, a relationship between capacitance values of the first capacitor and the second capacitor and a coil inductance of the induction coil satisfies the following limitation:

[0012]

[0013] Wherein, Lc is the coil inductance, ω is the magnetic field angular frequency of the external magnetic field, μeff is the effective magnetic permeability of the magnetic core, N is the number of turns of the induction coil, Acore is the cross-sectional area of the magnetic core, lcoil is the length of the magnetic core, Cp is the capacitance of the first capacitor and the second capacitor, μ0 is the vacuum permeability of the magnetic core.

[0014] Further, the magnetic field fluctuation self-adjusting module further comprises: an energy storage capacitor, a voltage dividing submodule, a voltage comparator, and a relay control submodule.

[0015] The first end of the energy storage capacitor is connected with the positive output end of the rectifier bridge, the first end of the energy storage capacitor is connected with the first end of the voltage dividing submodule, the first end of the voltage dividing submodule is the positive output end of the magnetic field fluctuation self-adjusting module, the second end of the voltage dividing submodule is connected with the reverse input end of the voltage comparator, the forward input end of the voltage comparator is connected with a reference voltage port preset by itself, the output end of the voltage comparator is connected with the input end of the relay control submodule, the first output end of the relay control submodule is the signal output end of the magnetic field fluctuation self-adjusting module, the second end of the energy storage capacitor is connected with the second output end of the relay control submodule, and the second output end of the relay control submodule is connected with the negative output end of the magnetic field fluctuation self-adjusting module.

[0016] Further, the voltage dividing submodule comprises: a first voltage dividing resistor and a second voltage dividing resistor.

[0017] The first end of the first voltage dividing resistor is the first end of the voltage dividing submodule, the second end of the first voltage dividing resistor is the second end of the voltage dividing submodule, the second end of the first voltage dividing resistor is connected with the first end of the second voltage dividing resistor, and the second end of the second voltage dividing resistor is the third end of the voltage dividing submodule.

[0018] The voltage dividing submodule is used for dividing the direct current output voltage to generate a voltage dividing voltage for inputting the voltage comparator.

[0019] Further, the relay control submodule comprises: an active controllable switch and a current limiting resistor.

[0020] The input end of the active controllable switch is the input end of the relay control submodule, the first output end of the active controllable switch is connected with the first end of the current limiting resistor, the second end of the current limiting resistor is the first output end of the relay control submodule, and the second output end of the active controllable switch is the second output end of the relay control submodule.

[0021] Further, the self-adaptive magnetic field fluctuation non-intrusive magnetic field energy collection device in the above embodiment further comprises: an energy management module.

[0022] The positive input end of the energy management module is connected with the positive output end of the magnetic field fluctuation self-adjusting module, the negative input end of the energy management module is connected with the negative output end of the magnetic field fluctuation self-adjusting module, the positive output end of the energy management module is connected with the positive pole of the load, and the negative output end of the energy management module is connected with the negative pole of the load.

[0023] The energy management module is used for providing electric energy to the load according to the direct current output voltage.

[0024] Further, the alternating current output voltage peak value of the alternating current induced voltage is:

[0025] V oc = ωμ eff NA core B ex ;

[0026] Wherein, V oc is the alternating current output voltage peak value, ω is the magnetic field angular frequency of the external magnetic field, μ eff is the effective magnetic permeability of the magnetic core, N is the number of turns of the induction coil, A core is the cross-sectional area of the magnetic core, B ex is the magnetic induction intensity of the external magnetic field.

[0027] Further, the voltage division voltage is:

[0028]

[0029] Wherein, V d is the voltage division voltage, R d1 is the first voltage value of the first voltage division resistor, R d2 is the second voltage value of the second voltage division resistor, and V o is the direct current output voltage.

[0030] Further, when the first capacitor is connected in series with the magnetic energy collection module, the first output power of the non-intrusive magnetic field energy collection device, and when the second capacitor is connected in parallel with the magnetic energy collection module, the second output power of the non-intrusive magnetic field energy collection device, are respectively:

[0031]

[0032] Wherein, P L,S is the first output power, P L,P is the second output power, R L is the equivalent resistance value of the rectifier bridge, the magnetic field fluctuation self-adjusting module, the energy management module and the load, R c is the coil resistance of the induction coil, and j is the imaginary unit.

[0033] By implementing the present application, the following advantages are achieved:

[0034] The application provides a non-invasive magnetic field energy collection device capable of self-adapting to magnetic field fluctuation, comprising a magnetic energy collection module, a compensation module, a rectifier bridge and a magnetic field fluctuation self-adjusting module, wherein the compensation module comprises a first capacitor, a first relay, a second capacitor and a second relay; when the capacitor in the compensation module is connected in parallel with the magnetic energy collection module, the alternating current input voltage can be improved, so the device is suitable for improving the voltage level under weak magnetic field conditions and ensuring the self-starting capability of the non-invasive magnetic field energy collection device; when the capacitor is connected in series with the magnetic energy collection module, the alternating current input voltage can be limited, so the device is suitable for suppressing the voltage level under strong magnetic field conditions and avoiding damage to circuit elements caused by excessively high voltage. The first relay and the second relay are arranged in the compensation module and connected with the magnetic field fluctuation self-adjusting module, so that the magnetic field fluctuation self-adjusting module generates a divided voltage according to the direct current output voltage, and compares the divided voltage with a preset reference voltage; when the divided voltage is greater than the reference voltage, it is determined that the current direct current output voltage is high, the voltage level needs to be suppressed, the first capacitor is connected in series with the magnetic energy collection module by disconnecting the first relay and the second relay, and the second capacitor is disconnected, so as to suppress the voltage level and avoid damage to circuit elements caused by excessively high voltage. When the divided voltage is not greater than the reference voltage, when the divided voltage is less than the reference voltage, it is determined that the current direct current output voltage is low, the voltage level needs to be improved, the first capacitor is short-circuited by turning on the first relay and the second relay, and the second capacitor is connected in parallel with the magnetic energy collection module, so as to improve the voltage and ensure the self-starting capability of the non-invasive magnetic field energy collection device. The non-invasive magnetic field energy collection device realizes the self-adaptive adjustment function of coping with wide-range magnetic field fluctuation and maintains the stable working state of the non-invasive magnetic field energy collection device. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0036] Figure 1 is a structural schematic diagram of a non-invasive magnetic field energy collection device capable of self-adapting to magnetic field fluctuation provided by an embodiment of the present application;

[0037] Figure 2 is a structural schematic diagram of an existing non-invasive magnetic field energy collection device provided by an embodiment of the present application;

[0038] Figure 3 is an equivalent circuit diagram of the non-intrusive magnetic field energy collection device provided by some embodiments of the present application;

[0039] Figure 4 is a curve graph of the change of the DC input voltage and the load power under different compensation modes provided by some embodiments of the present application. DETAILED DESCRIPTION

[0040] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without any creative work fall within the scope of protection of the present application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms “include” and “have” and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0042] In the description of the embodiments of the present application, the technical terms “first”, “second”, etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of “a plurality of” is two or more, unless otherwise explicitly and specifically limited.

[0043] Reference herein to “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0044] In the description of the embodiments of the present application, the term “and / or” is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character “ / ” herein generally represents a “or” relationship between the associated objects before and after it.

[0045] In the description of the embodiments of the present application, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0046] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0047] Referring to Figure 1 , overcome the defects that the existing non-invasive magnetic field energy collection device cannot adapt to wide range of magnetic field fluctuations, an embodiment of the present application provides a non-invasive magnetic field energy collection device which can adapt to magnetic field fluctuations, comprising: a non-invasive magnetic energy collection module 1, a compensation module 2, a rectifier bridge 3, and a magnetic field fluctuation self-adjusting module 4;Wherein, the compensation module 2, comprising: a first capacitor C p1 , a first relay SSR1, a second capacitor C p2 and a second relay SSR2;The first end of the first capacitor C p1 is connected with the positive electrode of the magnetic energy collection module 1, the second end of the first capacitor C p1 is connected with the first alternating current input end of the rectifier bridge 3, the first output end (D1) of the first relay SSR1 is connected with the first end of the first capacitor C p1 , the second output end (D2) of the first relay SSR1 is connected with the second end of the first capacitor C p1 , the first end of the second capacitor C p2 is connected with the second end of the first capacitor C p1 , the second end of the second capacitor C p2The second end of the first capacitor is connected with the first output end (D1) of the second relay SSR2, the second output end (D2) of the second relay SSR2 is connected with the negative electrode of the magnetic energy collection module 1 and the second alternating current input end of the rectifier bridge 3 respectively; the positive input end (A) of the first relay SSR1 is connected with the positive input end (A) of the second relay SSR2, and the positive input end (A) of the second relay SSR2 is connected with the positive output end of the magnetic field fluctuation self-adjusting module 4; the negative input end (C) of the first relay SSR1 is connected with the negative input end (C) of the second relay SSR2, and the negative input end (C) of the second relay SSR2 is connected with the signal output end of the magnetic field fluctuation self-adjusting module 4;

[0048] The magnetic energy collection module 1 is used for generating an alternating current induction voltage by inducting an external magnetic field;

[0049] The compensation module 2 is used for converting the alternating current induction voltage into an alternating current input voltage;

[0050] The rectifier bridge 3 is used for converting the alternating current input voltage into a direct current output voltage;

[0051] The magnetic field fluctuation self-adjusting module 4 is used for generating a voltage division voltage according to the direct current output voltage, comparing the voltage division voltage with a preset reference voltage, and disconnecting the first relay SSR1 and the second relay SSR2 when the voltage division voltage is greater than the reference voltage, and turning on the first relay and the second relay SSR2 when the voltage division voltage is less than the reference voltage.

[0052] Preferably, the alternating current output voltage peak value of the alternating current induction voltage is:

[0053] V oc = ωμ eff NA core B ex ;

[0054] Wherein, V oc is the alternating current output voltage peak value, ω is the magnetic field angular frequency of the external magnetic field, μ eff is the effective magnetic permeability of the magnetic core, N is the number of turns of the induction coil, A core is the cross-sectional area of the magnetic core, B ex is the magnetic induction intensity of the external magnetic field.

[0055] Preferably, when the first capacitor is connected in series with the magnetic energy collection module, the first output power of the non-intrusive magnetic field energy collection device, and when the second capacitor is connected in parallel with the magnetic energy collection module, the second output power of the non-intrusive magnetic field energy collection device, are respectively:

[0056]

[0057] Among them, P L,S For the first output power, P L,P For the second output power, R L R is the equivalent resistance value formed by the rectifier bridge, the magnetic field fluctuation self-adjustment module, the energy management module, and the load. c denoted as the coil resistance of the induction coil, where j is the imaginary unit.

[0058] In a preferred embodiment of the present invention, based on the principle that when the capacitor and the magnetic energy harvesting module are connected in parallel in the compensation module, the AC input voltage can be increased, while when the capacitor and the magnetic energy harvesting module are connected in series, the AC input voltage can be limited. This embodiment sets a first relay and a second relay in the compensation module, and connects them to the magnetic field fluctuation self-adjustment module. The magnetic field fluctuation self-adjustment module generates a voltage divider based on the DC output voltage and compares the voltage divider with a preset reference voltage. When the voltage divider is greater than the reference voltage, it can be determined that the current DC output voltage is high and needs to be suppressed. By disconnecting the first relay and the second relay, connecting the first capacitor in series with the magnetic energy harvesting module, and disconnecting the second capacitor, the voltage level is suppressed, preventing damage to circuit components due to excessive voltage. When the voltage divider is not greater than the reference voltage, or when the voltage divider is less than the reference voltage, it can be determined that the current DC output voltage is low and needs to be increased. By turning on the first relay and the second relay, short-circuiting the first capacitor, and connecting the second capacitor in parallel with the magnetic energy harvesting module, the voltage is increased, ensuring the self-starting capability of the non-invasive magnetic field energy harvesting device. To achieve the adaptive adjustment function of the non-invasive magnetic field energy harvesting device in response to a wide range of magnetic field fluctuations, and to maintain the stable working state of the non-invasive magnetic field energy harvesting device.

[0059] It should be noted that existing non-invasive magnetic field energy harvesting devices, such as Figure 2 As shown, the non-invasive magnetic field energy harvester is equivalent to an AC voltage source V. oc sin(ωt), resistance R c With inductor L c The compensation module topology is divided into two structures: series compensation and parallel compensation. To facilitate the analysis of the output characteristics of the magnetic energy harvester, the rectifier bridge and its downstream circuit can be considered as the equivalent load resistance R of the magnetic energy harvester. L Based on this, equivalent circuits for two different non-invasive magnetic field energy harvesting systems can be derived, such as... Figure 3 As shown, V in and I in Representing the equivalent load resistance R L The input voltage and input current,Figure 3 Fig. (a) is an equivalent circuit of a capacitive series compensation structure, and Fig. (b) is an equivalent circuit of a capacitive parallel compensation structure.

[0060] In Figure 3 the equivalent circuit shown, the AC output voltage peak value is:

[0061] V oc = ωμ eff NA core B ex ;

[0062] wherein V oc is the AC output voltage peak value, i.e. the coil open-circuit voltage peak value, ω is the magnetic field angular frequency of the external magnetic field, μ eff is the effective permeability of the magnetic core, N is the number of turns of the inductive coil, A core is the cross-sectional area of the magnetic core, and B ex is the external magnetic field magnetic induction intensity.

[0063] It can be seen that B ex can directly affect V oc , so in the case of a strong or weak external magnetic field, the value of V oc will also fluctuate significantly. When the external magnetic field is weak, the back-end equivalent load can not be able to start normally due to the coil open-circuit voltage peak value V oc being too low, and when the external magnetic field is strong, the back-end equivalent load can be damaged due to the coil open-circuit voltage peak value V oc being too high.

[0064] The inductive coil and the compensation capacitor form a resonant state, and the values of the coil inductance L c and the compensation capacitor value C p should satisfy the following conditions:

[0065]

[0066] wherein the value of L c is related to the length l coil of the magnetic core wound by the coil. Accordingly, the load power P L,S of the equivalent circuit of the capacitive series compensation structure and the load power P L,P of the equivalent circuit of the capacitive parallel compensation structure can be derived as follows:

[0067]

[0068] Further, the load voltage peak value V L can be derived as:

[0069]

[0070] V oc= 3V, R c = 100Ω, L c = 2H, C p = 5.066μF, the DC input voltage and load power corresponding to different load resistances under the capacitor series compensation structure and the capacitor parallel compensation structure are measured, and the change curves of the input voltage and the load power under different compensation modes are obtained, as shown in Figure 4

[0071] As can be seen from Figure 4 , the capacitor parallel compensation structure has the function of improving the input voltage level, so it can be used in a weak magnetic field condition, and the self-starting ability of the non-intrusive magnetic field energy collection system is ensured by improving the input voltage level; and the capacitor series compensation structure can effectively limit the input voltage level, so it can be used in a strong magnetic field condition, and the circuit components are prevented from being damaged due to high voltage by limiting the input voltage level.

[0072] Preferably, the magnetic energy collection module 1 comprises a magnetic core and an induction coil.

[0073] In a preferred embodiment of the present application, the magnetic energy collection module 1 is consistent with the non-intrusive magnetic field energy collector structure as shown in Figure 2 , which is composed of a non-closed magnetic core and an induction coil, and based on the principle of electromagnetic induction. An alternating current induction voltage can be generated at both ends of the coil under the action of an external magnetic field.

[0074] Preferably, the capacitance values of the first capacitor C p1 and the second capacitor C p2 and the coil inductance L C of the induction coil satisfy the following restrictions:

[0075]

[0076] wherein L c is the coil inductance, ω is the magnetic field angular frequency of the external magnetic field, μ eff is the effective permeability of the magnetic core, N is the number of turns of the induction coil, A core is the cross-sectional area of the magnetic core, l coil is the length of the magnetic core, C p is the capacitance value of the first capacitor and the second capacitor, and μ0 is the vacuum permeability of the magnetic core.

[0077] In a preferred embodiment of the present application, according to the derivation above, the relationship restrictions between the capacitance values of the first capacitor and the second capacitor and the coil inductance of the induction coil are not repeated here. Further, based on the relationship restrictions, the capacitance values of the first capacitor C p1 and the second capacitor C p2 ​The selection of the type provides a basis for determining the capacity interval of the first capacitor C p1 and the second capacitor C p2 according to the structural parameters of the induction coil and the magnetic energy of the environment in which the non-intrusive magnetic field energy collection device is located.

[0078] Preferably, the magnetic field fluctuation self-adjusting module 4 further comprises an energy storage capacitor C O , a voltage dividing submodule 41, a voltage comparator Comp, and a relay control submodule 42.

[0079] The first end of the energy storage capacitor C O is connected to the positive output end of the rectifier bridge 3, and the first end of the energy storage capacitor C O is connected to the first end of the voltage dividing submodule 41, and the first end of the voltage dividing submodule 41 is the positive output end of the magnetic field fluctuation self-adjusting module 4. The second end of the voltage dividing submodule 41 is connected to the reverse input end of the voltage comparator Comp, the forward input end of the voltage comparator Comp is connected to the reference voltage port preset by itself, the output end of the voltage comparator Comp is connected to the input end of the relay control submodule 42, the first output end of the relay control submodule 42 is the signal output end of the magnetic field fluctuation self-adjusting module 4, and the second end of the energy storage capacitor C O is connected to the second output end of the relay control submodule 42, which is the negative output end of the magnetic field fluctuation self-adjusting module 4.

[0080] Preferably, the voltage dividing submodule 41 comprises a first voltage dividing resistor R1 and a second voltage dividing resistor R2.

[0081] The first end of the first voltage dividing resistor R1 is the first end of the voltage dividing submodule 41, the second end of the first voltage dividing resistor R1 is the second end of the voltage dividing submodule 41, the second end of the first voltage dividing resistor R1 is connected to the first end of the second voltage dividing resistor R2, and the second end of the second voltage dividing resistor R2 is the third end of the voltage dividing submodule 41.

[0082] The voltage dividing submodule 41 is used to divide the DC output voltage to generate a voltage dividing voltage for inputting the voltage comparator Comp.

[0083] Preferably, the relay control submodule 42 comprises an active controllable switch NMOS and a current limiting resistor R F .

[0084] The input end of the active controllable switch NMOS is the input end of the relay control submodule 42, the first output end of the active controllable switch NMOS is connected to the current limiting resistor RF The first end is connected to the current-limiting resistor R. F The second terminal is the first output terminal of the relay control submodule 42, and the second output terminal of the active controllable switch NMOS is the second output terminal of the relay control submodule 42.

[0085] Preferably, the voltage divider voltage is:

[0086]

[0087] Among them, V d For voltage divider voltage, R d1 R is the first voltage value of the first voltage divider resistor R1. d2 V is the second voltage value of the second voltage divider resistor R2. o This is the DC output voltage.

[0088] In a preferred embodiment of the present invention, such as Figure 1 As shown, rectifier bridge 3 and energy storage capacitor C o In parallel, the positive output terminal of rectifier bridge 3 is connected in parallel with the first voltage divider resistor R1. The first voltage divider resistor R1 is connected in series with the second voltage divider resistor R2. Finally, the second voltage divider resistor R2 is connected to the negative output terminal of rectifier bridge 3. The positive input terminal of voltage comparator Comp is connected to its internal reference voltage V. ref The ports are connected, with the inverting input terminal connected between the first voltage divider resistor R1 and the second voltage divider resistor R2. In this embodiment, the active controllable switch NMOS uses an NMOS transistor, therefore the output terminal of the voltage comparator Comp is connected to the gate (input terminal) of the active controllable switch NMOS. The input terminals of the first relay SSR1 and the first relay SSR2 are connected in parallel, with their positive input terminals connected to the positive output terminal of the magnetic field fluctuation self-adjustment module 4, and their negative input terminals connected to the current limiting resistor R. F The voltage comparator Comp is connected in series with an NMOS transistor, and its supply voltage is V. cc .

[0089] In the magnetic field fluctuation self-adjustment module 4, based on the voltage divider voltage V d The external magnetic field environment is determined by a voltage comparator Comp. When the external magnetic field strength is weak, the first relays SSR1 and SSR2 are activated, adjusting the circuit structure in compensation module 2 to a parallel capacitor compensation structure. At this time, the circuit operates in parallel resonant mode, which can increase the DC input voltage V. in The level ensures the normal startup of the back-end circuit; when the external magnetic field strength is strong, the first relay SSR1 and the first relay SSR2 are disconnected. At this time, the compensation module 2 is in series resonant mode, which can limit the input voltage V. in To ensure the circuit components are at the correct level, thus preventing damage.

[0090] Specifically, the reference voltage V ref According to the starting voltage required by the energy management module, if the voltage V d is less than the reference voltage V ref , it indicates that the voltage V d at this time is small, the DC output voltage V o at this time is also small, and it can be judged that the DC input voltage V in at this time is small, that is, the AC induced voltage generated by the magnetic energy collection module 1 at this time is small, so it is judged that it is in a weak external magnetic field environment at this time. According to the basic principle of the voltage comparator, when the voltage V d is less than the reference voltage V ref , the output voltage V EN is high, which can make the NMOS transistor conduct, and then make the first relay SSR1 and the second relay SSR2 conduct, so at this time the first relay SSR1 is turned on, the first capacitor C p1 in the compensation module 2 is short-circuited, and the output of the second relay SSR2 is also turned on, so that the compensation module 2 is in a parallel compensation structure state, realizing the function of working in a parallel resonance mode in a weak external magnetic field environment.

[0091] If the voltage V d is greater than the reference voltage V ref , it indicates that the voltage V d at this time is large, the DC output voltage V o at this time is also large, and it can be judged that the DC input voltage V in at this time is large, that is, the AC induced voltage generated by the magnetic energy collection module 1 at this time is large, so it is judged that it is in a strong external magnetic field environment at this time. According to the basic principle of the voltage comparator, when the voltage V d is greater than the reference voltage V ref , the output voltage V EN is low, the NMOS transistor is in an off state, and the first relay SSR1 and the second relay SSR2 are also in an off state, so at this time the output of the first relay SSR1 is disconnected, the first capacitor C p1 in the compensation module is connected to the circuit, and the output of the second relay SSR2 is also disconnected, so that the compensation module 2 is in a series compensation structure state, realizing the function of working in a series resonance mode in a strong external magnetic field environment.

[0092] It should be noted that when the voltage is equal to the reference voltage, the original state is maintained, for example, when the voltage decreases from a state greater than the reference voltage to a state equal to the reference voltage, the voltage comparator continues to output low in the equal case, until the voltage is less than the reference voltage, output high, vice versa, when the voltage increases from a state less than the reference voltage to a state equal to the reference voltage, the voltage comparator continues to output high in the equal case, until the voltage is greater than the reference voltage, output low.

[0093] Further, compared with the prior art method of adjusting the corresponding control parameters to maintain the stable working state of the device according to the specific value of the external magnetic field strength, the embodiment adaptively switches the circuit structure of the compensation module through the magnetic field fluctuation self-adjusting module, and the related parameters (reference voltage) are all fixed values, which overcomes the defect that the current method is difficult to accurately control the control parameters when the external magnetic field strength is in a state of continuous fluctuation and is difficult to detect in the actual application scene.

[0094] Preferably, the non-invasive magnetic field energy harvesting device with adaptive magnetic field fluctuation according to the above embodiment further comprises an energy management module 5.

[0095] The positive input end of the energy management module 5 is connected with the positive output end of the magnetic field fluctuation self-adjusting module 4, the negative input end of the energy management module 5 is connected with the negative output end of the magnetic field fluctuation self-adjusting module 4, the positive output end of the energy management module 5 is connected with the positive pole of the load, and the negative output end of the energy management module is connected with the negative pole of the load.

[0096] The energy management module 5 is used for providing electric energy to the load according to the direct current output voltage.

[0097] In a preferred embodiment of the present application, the non-invasive magnetic field energy harvesting device is further provided with an energy management module 5, which is used for optimizing energy distribution on one hand, and regulating the release of energy storage capacitor electric energy according to the demand of the load (sensor) to ensure stable power output; on the other hand, it has the functions of protection and efficiency, protects the load, optimizes the circuit topology (such as DC-DC conversion) to improve energy utilization efficiency, and supplies electric energy to the sensor efficiently.

[0098] It should be noted that the apparatus embodiments described above are merely illustrative, and the modules / units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment according to actual needs. In addition, the connection between the modules in the apparatus embodiment provided by the present application indicates that there is a communication connection between them, which can be implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement it without creative labor.

[0099] Those skilled in the art can clearly understand that, for the convenience and brevity, the specific working process of the apparatus described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0100] The above is the preferred embodiment of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which are also considered within the scope of protection of the present application.

Claims

1. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device, characterized by, The application relates to a non-invasive magnetic energy collection module, a compensation module, a rectifier bridge and a magnetic field fluctuation self-adjusting module. The compensation module comprises a first capacitor, a first relay, a second capacitor and a second relay; the first end of the first capacitor is connected with the positive pole of the magnetic energy collection module, the second end of the first capacitor is connected with the first alternating current input end of the rectifier bridge, the first output end of the first relay is connected with the first end of the first capacitor, the second output end of the first relay is connected with the second end of the first capacitor, the first end of the second capacitor is connected with the second end of the first capacitor, the second end of the second capacitor is connected with the first output end of the second relay, the second output end of the second relay is connected with the negative pole of the magnetic energy collection module and the second alternating current input end of the rectifier bridge respectively, the positive pole input end of the first relay is connected with the positive pole input end of the second relay, the positive pole input end of the second relay is connected with the positive pole output end of the magnetic field fluctuation self-adjusting module, the negative pole input end of the first relay is connected with the negative pole input end of the second relay, and the negative pole input end of the second relay is connected with the signal output end of the magnetic field fluctuation self-adjusting module. The magnetic energy collection module is used for generating alternating current induction voltage by inducting external magnetic field. The compensation module is used for converting the alternating current induction voltage into alternating current input voltage. The rectifier bridge is used for converting the alternating current input voltage into direct current output voltage. The magnetic field fluctuation self-adjusting module is used for generating voltage division voltage according to the direct current output voltage, comparing the voltage division voltage with a preset reference voltage, disconnecting the first relay and the second relay when the voltage division voltage is greater than the reference voltage, and conducting the first relay and the second relay when the voltage division voltage is smaller than the reference voltage.

2. A self-adapting magnetic field fluctuation non-invasive magnetic field energy harvesting device as claimed in claim 1, wherein, The magnetic energy collection module comprises a magnetic core and an induction coil.

3. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 2, wherein, The relationship between the capacitance values of the first capacitor and the second capacitor and the coil inductance of the induction coil satisfies the following limitation. wherein L c is the inductance of the coil, ω is the magnetic field angular frequency of the external magnetic field, μ eff is the effective permeability of the magnetic core, N is the number of turns of the inductive coil, A core is the cross-sectional area of the magnetic core, l coil is the length of the magnetic core, C p is the capacitance value of the first and second capacitors, and μ0 is the vacuum permeability of the magnetic core.

4. A self-adapting magnetic field fluctuation non-invasive magnetic field energy harvesting device as claimed in claim 3, wherein, The magnetic field fluctuation self-adjusting module further comprises an energy storage capacitor, a voltage division sub-module, a voltage comparator and a relay control sub-module. The first end of the energy storage capacitor is connected with the positive pole output end of the rectifier bridge, the first end of the energy storage capacitor is connected with the first end of the voltage division sub-module, the first end of the voltage division sub-module is the positive pole output end of the magnetic field fluctuation self-adjusting module, the second end of the voltage division sub-module is connected with the reverse input end of the voltage comparator, the forward input end of the voltage comparator is connected with a preset reference voltage port of the voltage comparator, the output end of the voltage comparator is connected with the input end of the relay control sub-module, the first output end of the relay control sub-module is the signal output end of the magnetic field fluctuation self-adjusting module, the second end of the energy storage capacitor is connected with the second output end of the relay control sub-module, and the second output end of the relay control sub-module is connected with the negative pole output end of the magnetic field fluctuation self-adjusting module.

5. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 4, wherein, The voltage division sub-module comprises a first voltage division resistor and a second voltage division resistor. The first end of the first voltage divider resistor is the first end of the voltage divider submodule, the second end of the first voltage divider resistor is the second end of the voltage divider submodule, the second end of the first voltage divider resistor is connected to the first end of the second voltage divider resistor, and the second end of the second voltage divider resistor is the third end of the voltage divider submodule.

6. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 5, wherein, The relay control submodule includes: an active controllable switch and a current-limiting resistor; The input terminal of the active controllable switch is the input terminal of the relay control submodule. The first output terminal of the active controllable switch is connected to the first terminal of the current limiting resistor. The second terminal of the current limiting resistor is the first output terminal of the relay control submodule. The second output terminal of the active controllable switch is the second output terminal of the relay control submodule.

7. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 6, wherein, Also includes: Energy management module; The positive input terminal of the energy management module is connected to the positive output terminal of the magnetic field fluctuation self-adjustment module, the negative input terminal of the energy management module is connected to the negative output terminal of the magnetic field fluctuation self-adjustment module, the positive output terminal of the energy management module is connected to the positive terminal of the load, and the negative output terminal of the energy management module is connected to the negative terminal of the load. The energy management module is used to provide electrical energy to the load based on the DC output voltage.

8. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 7, wherein, The peak value of the AC output voltage of the AC induced voltage is: V oc = ωμ eff NA core B ex ; Wherein, V oc is the peak value of the alternating output voltage, ω is the magnetic field angular frequency of the external magnetic field, μ eff is the effective permeability of the magnetic core, N is the number of turns of the induction coil, A core is the cross-sectional area of the magnetic core, B ex is the magnetic induction intensity of the external magnetic field.

9. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 8, wherein, The voltage divider voltage is: wherein V d is the voltage of the first voltage divider, R d1 is the first voltage value of the first voltage divider, R d2 is the second voltage value of the second voltage divider, V o is the DC output voltage.

10. A self-adapting magnetic field fluctuation non-intrusive magnetic field energy harvesting device as claimed in claim 9, wherein, When the first capacitor is connected in series with the magnetic energy harvesting module, the first output power of the non-invasive magnetic field energy harvesting device, and when the second capacitor is connected in parallel with the magnetic energy harvesting module, the second output power of the non-invasive magnetic field energy harvesting device are respectively: wherein P L,S is the first output power, P L,P is the second output power, R L is the equivalent resistance value of the rectifier bridge, the magnetic field fluctuation self-adjusting module, the energy management module, and the load, R c is the coil resistance of the induction coil, and j is the imaginary unit.

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