Current sensor, electronic device, and current measurement method

Abstract

The invention discloses a current sensor, electronic equipment and a measuring method thereof, and relates to the technical field of current detection. The current sensor comprises a mutual inductance module which is used for sensing an alternating magnetic field generated by a wire and outputting a first signal; the protection module is used for outputting a second signal which is lower than a first threshold value in the first signal; the current acquisition module is used for adjusting the voltage of the first resistor according to the second signal and outputting a third signal; the rectification module is used for adjusting the second signal into a direct current signal; the energy storage voltage stabilization module is used for storing the direct current signal as electric energy and supplying power to the control module; and the control module is used for determining whether to drive the DC signal to be transmitted to the energy storage voltage stabilization module and the second signal to be transmitted to the current acquisition unit according to the current voltage of the energy storage voltage stabilization module, and determining the current of the wire according to the third signal. According to the invention, while CT power taking and current measurement are realized, repeated arrangement of the mutual inductance module and the protection module is avoided, and the size of the current sensor and the equipment cost can be greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of current detection, and in particular to a current sensor, electronic equipment and a current measuring method. Background Art

[0002] A current sensor is a device for detecting current. It is generally used in actual current measurement and protection systems, such as photovoltaics, wind power, electricity, smart grids, railway electromechanical, aerospace, new energy vehicles and other fields. As the main detection element, the current sensor plays a vital role in ensuring the safety and stability of the system.

[0003] Since current sensors are not used for passive current measurement, how to power high-voltage current sensors often becomes a very critical issue. For example, when monitoring high-voltage overhead lines, power cables, distribution units, etc., there is generally no suitable low-voltage power supply nearby for current sensors to use.

[0004] At present, current transformers are mainly used to draw power from high-voltage lines. If current transformers are directly used in current sensors, the size and cost of the equipment will increase. Summary of the invention

[0005] The main purpose of the present invention is to provide a current sensor, an electronic device and a current measurement method with a current transformer, aiming to solve the technical problem of large volume caused by directly applying the current transformer to the current sensor in the prior art.

[0006] To achieve the above object, a first aspect of the present invention provides a current sensor, comprising: A mutual inductance module, used for sensing an alternating magnetic field generated by a conductor in the annular magnetic core, and outputting a first signal through a coil surrounding the annular magnetic core; A protection module, configured to output a second signal of the first signal that is lower than a first threshold; a current acquisition module, used for adjusting the voltage of the first resistor according to the second signal and outputting a third signal; A rectifier module, used for adjusting the second signal into a DC signal with a higher voltage; An energy storage and voltage stabilization module, used for storing the DC signal as electric energy with a stable voltage, and / or for supplying power to a control module; The control module is used to collect the current voltage of the energy storage and voltage stabilization module, determine the current of the wire according to the third signal, determine whether to drive the DC signal to be transmitted to the energy storage and voltage stabilization module according to the current voltage, and determine whether to drive the second signal to be transmitted to the current collection unit according to the current voltage.

[0007] According to some embodiments of the present invention, the control module comprises: A first switch, located between the protection module and the current acquisition module, and used to control the coupling state between the protection module and the current acquisition module; A second switch, located between the rectifier module and the energy storage and voltage stabilization module, for controlling the coupling state of the rectifier module and the energy storage and voltage stabilization module; A voltage collection unit, electrically coupled to the energy storage and voltage stabilization module, for collecting the current voltage of the energy storage and voltage stabilization module; a current determining unit, electrically coupled to the current collecting unit, and configured to determine a current current of the wire according to the third signal; A control unit, configured to obtain the current voltage and the current current, drive the second switch and the first switch to be in an open state and a closed state respectively when the current voltage is higher than a second threshold value and determine the current current as the current value of the wire, and drive the second switch and the first switch to be in a closed state and an open state respectively when the current voltage drops to a third threshold value and stop determining the current current as the current value of the wire; The energy storage and voltage stabilization module is used to supply power to the voltage acquisition unit, the current determination unit and the control unit, and the supply voltage is a first voltage.

[0008] According to some embodiments of the present invention, the first switch is a normally-open field effect transistor, and the second switch is a normally-closed field effect transistor; The control unit can further control the closing state of the first switch by adjusting the voltage of the first switch; The control unit can further control the closing state of the second switch by adjusting the voltage of the second switch.

[0009] According to some embodiments of the present invention, the mutual inductance module includes the annular magnetic core and the coil; The coil is used to sense the alternating magnetic field generated by the alternating electric field in the conductor, and generate an induced electromotive force under the action of the alternating magnetic field; The coil is made of a high magnetic permeability material.

[0010] According to some embodiments of the present invention, the protection module is used to monitor the voltage of the first signal and compare the voltage with the first threshold value, transmit the first signal to the discharge unit for release when the voltage is higher than the first threshold value, and output the first signal to the rectifier module or the current acquisition module when the voltage is lower than the first threshold value.

[0011] According to some embodiments of the present invention, the energy storage and voltage stabilization module includes: an energy storage capacitor unit, electrically coupled to the output end of the rectifier module, and used to store the DC signal as electrical energy; A voltage stabilizing unit is electrically coupled to the energy storage capacitor unit and is used to adjust the output voltage of the energy storage voltage stabilizing module to at least one preset voltage; when the energy storage voltage stabilizing module supplies power to the control module, the preset voltage is the first voltage.

[0012] According to some embodiments of the present invention, the control unit is configured to perform the following steps in sequence when the current voltage is higher than a second threshold: driving the first switch to a closed state; driving the second switch to an off state; Acquire a third signal output by the current acquisition module; A current value of the wire is determined according to the third signal.

[0013] According to some embodiments of the present invention, the control unit is configured to sequentially perform the following steps when the current voltage is lower than a third threshold: driving the second switch to a closed state; The first switch is driven to be in an off state.

[0014] To achieve the above object, a second aspect of the present invention provides a current measurement method, using the above current sensor, the method comprising the following steps: The alternating magnetic field generated by the conductor in the annular magnetic core is sensed by a mutual inductance module, a protection module, a rectification module, and an energy storage and voltage stabilization module which are electrically coupled in sequence, and the electric energy with a stable voltage is stored in the energy storage and voltage stabilization module; Powering the control module through the energy storage and voltage stabilization module; Continuously collecting the current voltage of the energy storage and voltage stabilization module through the control module; The control module determines whether the current voltage is higher than a second threshold value, and when the current voltage is higher than the second threshold value, drives the rectifier module to disconnect from the energy storage and voltage stabilization module, and electrically couples the rectifier module to the current acquisition module, thereby sensing the current of the wire through the current acquisition module and outputting a third signal; The control module determines the current value of the wire according to the third signal through the control unit; The control unit determines whether the current voltage drops to a third threshold value, and when the current voltage is lower than the third threshold value, drives the rectifier module to disconnect from the energy storage and voltage stabilization module and electrically couples the rectifier module to the current acquisition module, so as to store electrical energy in the energy storage and voltage stabilization module again.

[0015] To achieve the purpose of the present invention, a third aspect of the present invention provides an electronic device, which includes at least a current sensor; the current sensor is the above-mentioned current sensor, or a current sensor made by the above-mentioned current measurement method.

[0016] Compared with the prior art, the present invention has the following technical effects: The current sensor disclosed in the invention realizes the CT power supply and current measurement functions through the coordinated action of the mutual inductance module, the protection module, the current acquisition module, the rectification module, the energy storage voltage stabilization module and the control module, while avoiding the repeated setting of the mutual inductance module and the protection module, which can greatly reduce the volume of the current sensor and reduce the equipment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0018] Figure 1 is a schematic structural diagram of a current sensor according to an embodiment of the present invention; Figure 2 Schematic diagram of a flow chart of a current measurement method according to an embodiment of the present invention.

[0019] Description of Figure Numbers: 100, mutual inductance module; 200, protection module; 300, rectification module; 400, energy storage and voltage stabilization module; 500, control module; 600, current acquisition module; S1, first switch; S2, second switch.

[0020] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0023] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0024] A current sensor is a device for detecting current. It is generally used in actual current measurement and protection systems, such as photovoltaics, wind power, electricity, smart grids, railway electromechanical, aerospace, new energy vehicles and other fields. As the main detection element, the current sensor plays a vital role in ensuring the safety and stability of the system.

[0025] Since current sensors are active measurements, how to power high-voltage current sensors often becomes a critical issue. For example, when monitoring high-voltage overhead lines, power cables, distribution units, etc., there is generally no suitable low-voltage power supply nearby for current sensors to use.

[0026] At present, current transformers are mainly used to draw power from high-voltage lines. If current transformers are directly used in current sensors, the size and cost of the equipment will increase.

[0027] Therefore, it is necessary to solve the technical problem of bulky volume caused by directly applying the current transformer to the current sensor in the prior art.

[0028] To achieve the above-mentioned purpose, an embodiment of the present invention provides a current sensor. The current sensor includes a mutual inductance module, a protection module, a rectifier module, an energy storage and voltage stabilization module, a control module and a current acquisition module, wherein when the mutual inductance module, the protection module, the rectifier module and the energy storage and voltage stabilization module are electrically coupled in sequence, the current sensor can realize the energy storage process of the energy storage capacitor in the energy storage and voltage stabilization module; when the mutual inductance module, the protection module, the current acquisition module and the control module are electrically coupled in sequence, the current sensor can realize the current measurement of the wire in the annular magnetic core in the mutual inductance module; when the energy storage and voltage stabilization module is electrically coupled to the control module, the current sensor can realize power supply to the control module and monitor the real-time voltage of the energy storage and voltage stabilization module through the control module. The electrical coupling relationship between the rectifier module and the energy storage and voltage stabilization module and the electrical coupling relationship between the protection module and the current acquisition module can be driven and changed by the control module.

[0029] Specifically, Figure 1 As shown, the current sensor of the embodiment of the present invention includes a mutual inductance module 100 , a protection module 200 , a rectification module 300 , an energy storage and voltage stabilization module 400 , a control module 500 and a current acquisition module 600 .

[0030] The mutual inductance module 100 includes a ring-shaped magnetic core and a coil surrounding the ring-shaped magnetic core.

[0031] The mutual inductance module 100 may be used to sense the alternating magnetic field generated by the conductive wire in the annular magnetic core, and output a first signal through a coil surrounding the annular magnetic core.

[0032] The coil is used to sense the alternating magnetic field generated by the alternating electric field in the induction wire and generate an induced electromotive force under the action of the alternating magnetic field. The coil is preferably made of a high magnetic permeability material.

[0033] Since the energy extraction and current measurement functions are realized at the same time, the magnetic core is preferably made of a soft magnetic material with high magnetic permeability, such as Permalloy, nanocrystal, etc. A magnetic core with high initial magnetic permeability can achieve a better energy extraction effect under low current conditions.

[0034] The protection module 200 may be used to obtain a second signal in the first signal that is lower than a first threshold.

[0035] The protection module 200 is used to monitor the voltage of the first signal and compare the voltage of the first signal with a first threshold. If the voltage of the first signal is not lower than the first threshold, the first signal is pushed to the discharge unit for release. If the voltage of the first signal is lower than the first threshold, the first signal is output, which ensures that the second signal output by the protection module 200 is a signal in the first signal that is lower than the first threshold.

[0036] The protection module 200 of the embodiment of the present invention includes a thyristor, a power resistor and a voltage comparator. When it is detected that the voltage of the first signal exceeds the first threshold, the thyristor is driven to conduct, and the excess electrical energy is converted into heat energy through the power resistor for discharge.

[0037] In another embodiment, the protection module 200 includes a transient overvoltage protection unit and an energy discharge unit. The transient overvoltage protection unit is electrically coupled to the output end of the coil in the mutual inductance module to protect the rectifier module 300, the energy storage voltage stabilization module 400, the control module 500, the current acquisition module 600, etc. in the subsequent circuit from being damaged by transient overvoltage. The energy discharge unit is electrically coupled to the output end of the transient overvoltage protection unit. The energy discharge unit includes an energy discharge topology and a comparator, which can be used to prevent the output of a signal not lower than a first threshold.

[0038] The rectifying module 300 is used to rectify and filter the second signal and output a DC signal.

[0039] The rectifier module 300 may adopt a voltage doubling rectifier circuit, through which the second signal is rectified and filtered to output a DC signal, while increasing the voltage of the DC signal, that is, the voltage of the DC signal is higher than the voltage of the second signal.

[0040] It should be understood that the voltage output by the coil in the mutual inductance module 100 is generally low, and obtaining a sufficiently high voltage through the voltage doubling rectifier circuit can improve the working efficiency of the energy storage and voltage stabilization module 400.

[0041] The current acquisition module 600 is used to adjust the voltage of the first resistor according to the second signal and output a third signal.

[0042] The current acquisition module 600 includes a first resistor, and the voltage across the first resistor changes with the second signal. The third signal is used to feed back the voltage information across the first resistor.

[0043] The energy storage and voltage stabilization module 400 is used to store the DC signal as electric energy with a stable voltage and to supply power to the control module.

[0044] The energy storage and voltage stabilization module 400 of the embodiment of the present invention is also used to ensure the stability of the internal power supply of the current sensor, so as to prevent the influence of power grid fluctuation on the stability of the sensor operation.

[0045] When the rectifier module 300 is electrically coupled to the energy storage and voltage stabilizing module 400, the mutual inductance module 100, the protection module 200, the rectifier module 300 and the energy storage and voltage stabilizing module 400 are electrically coupled in sequence, which can realize the conversion of the alternating magnetic field of the wire into electrical energy storage, and after storing a certain amount of electricity, it can be used as a power source to supply power to the control module.

[0046] When the protection module 200 is electrically coupled with the current acquisition module 600, the mutual inductance module 100, the protection module 200, the current acquisition module 600 and the control module 500 are electrically coupled in sequence. On the premise that the energy storage and voltage stabilization module 400 supplies power to the control module, the alternating magnetic field generated by the conductor is collected to thereby determine the current current of the conductor.

[0047] It should be understood that the premise of this step is that the energy storage capacitor in the energy storage and voltage stabilization module 400 stores sufficient electrical energy.

[0048] The energy storage and voltage stabilization module 400 of the embodiment of the present invention includes an energy storage capacitor unit and a voltage stabilization unit. The energy storage capacitor unit is used to convert the alternating magnetic field into electrical energy; the voltage stabilization unit is used to stabilize the output voltage of the energy storage and voltage stabilization module.

[0049] The control module 500 is used to collect the current voltage of the energy storage and voltage stabilization module.

[0050] When the voltage of the energy storage capacitor in the energy storage and voltage stabilization module 400 is large enough, the energy storage and voltage stabilization module 400 can supply power to the control module 500, so that the control module 500 can collect the current voltage of the energy storage and voltage stabilization module 400. When the current voltage of the energy storage capacitor is higher than the second threshold, the control module can drive the current collection module to realize the measurement function.

[0051] The control module 500 of the embodiment of the present invention includes a voltage acquisition unit and a control unit. The current acquisition unit is electrically coupled to the energy storage voltage stabilization unit for acquiring the current voltage of the energy storage capacitor in the energy storage voltage stabilization module 400. The control module 500 is used to obtain the current voltage and determine whether to drive the protection module 200 to be electrically coupled to the current acquisition module 600 based on the current voltage, and determine whether to drive the energy storage voltage stabilization module 400 to be electrically coupled to the rectifier module 300 based on the current voltage.

[0052] When the current voltage value is higher than the second threshold, the control module 500 preferably first drives the protection module 200 to achieve electrical coupling with the current acquisition module, then drives the energy storage voltage stabilization module to disconnect the electrical coupling with the rectifier module, and then receives the third signal output by the current acquisition module and determines the current value of the wire according to the third signal.

[0053] It should be understood that before disconnecting the electrical coupling between the energy storage and voltage stabilizing module 400 and the rectifier module 300, the electrical coupling between the protection module 200 and the current acquisition module 600 is realized in advance, so as to avoid the high-energy signal transmitted through the coil from causing damage to other components in the current sensor, thereby affecting the normal use of the current sensor.

[0054] The control module 500 of the embodiment of the present invention further includes a first switch S1 and a second switch S2; the first switch S1 is located between the protection module 200 and the current acquisition module, and is used to control the coupling state of the protection module 200 and the current acquisition module; the second switch S2 is located between the rectifier module and the energy storage voltage stabilizing module, and is used to control the coupling state of the rectifier module and the energy storage voltage stabilizing module. The control unit can adjust the voltage of the first switch S1 and the second switch S2, and is further used to control the voltage of the first switch S1 according to the current voltage of the energy storage capacitor to make the first switch S1 open or closed; and is also used to control the voltage of the second switch S2 according to the current voltage of the energy storage capacitor to make the second switch S2 open or closed.

[0055] The first switch S1 and the second switch S2 of the embodiment of the present invention are MOS switches, specifically, the first switch S1 is a normally open field effect transistor, and the second switch S2 is a normally closed field effect transistor. The first switch S1 and the second switch S2 may also be other types of switches, which are not specifically limited here.

[0056] The control module 500 of the embodiment of the present invention further includes a current determination unit. The current determination unit is used to determine the current of the wire according to the third signal output by the current acquisition unit. To avoid errors, the control module only processes the acquired third signal after a certain period of time after the energy storage and voltage stabilization module supplies power to the control module. The duration is not specifically limited here.

[0057] In some embodiments, the current determination unit may also limit the strength of the received third signal to avoid receiving an erroneous signal, which is not specifically limited here.

[0058] In some embodiments, the control unit is also used to execute the following steps in sequence when the current voltage of the energy storage capacitor is higher than a second threshold, that is, when it is fully charged: drive the first switch S1 to a closed state, drive the second switch S2 to an open state, obtain a third signal output by the current acquisition module, and determine the current value of the wire based on the third signal.

[0059] In some embodiments, the control unit is further configured to perform the following steps in sequence when the current voltage of the energy storage capacitor is lower than a third threshold, that is, when the power is exhausted: drive the second switch S2 to a closed state, and drive the first switch S1 to an open state.

[0060] The control module 500 of the embodiment of the present invention further includes a communication unit electrically coupled to the control unit, and the communication unit is used to transmit the determined current value to an external device via wireless transmission.

[0061] It should be understood that the energy storage and voltage stabilization module 400 is also used to power the communication unit so that the communication unit can achieve the communication function without an additional power supply.

[0062] To achieve the above object, an embodiment of the present invention further provides a current measurement method. The current measurement method uses the above current sensor. The current measurement method includes the following steps: S100, inducing the alternating magnetic field generated by the wire in the annular magnetic core through the mutual inductance module, the protection module, the rectification module, and the energy storage and voltage stabilization module that are electrically coupled in sequence, and storing the electric energy with a stable voltage in the energy storage and voltage stabilization module; Specifically, before the control module participates in the current measurement, the mutual inductance module, the protection module, the rectifier module, and the energy storage voltage stabilization module are coupled in sequence, and the mutual inductance module is used to sense the exchange magnetic field generated by the wire in the annular magnetic core to output a first signal, which can realize the energy extraction function; the protection module is used to prevent the voltage of the first signal output by the mutual inductance module from being too high, and then pre-screen the first signal, and output a second signal that is lower than the first threshold; S200, supplying power to the control module through the energy storage voltage stabilization module; Specifically, when the electric energy stored in the energy storage and voltage stabilization module reaches a certain level, the energy storage and voltage stabilization module supplies power to the control module to start the normal operation of the control module.

[0063] S300, continuously collecting the current voltage of the energy storage voltage stabilization module through the control module; Specifically, the current voltage of the energy storage and voltage stabilization module, ie, the current voltage across the energy storage capacitor, is collected through the voltage collection unit of the control module, and it is determined that the current voltage is lower than the second threshold.

[0064] S400, the control module determines whether the current voltage is not lower than the second threshold value, and when the current voltage is higher than the second threshold value, drives the rectifier module to disconnect the coupling with the energy storage voltage stabilization module, and electrically couples the rectifier module with the current acquisition module, and then senses the current of the wire through the current acquisition module, and outputs a third signal; Specifically, when it is determined that the current voltage is higher than the second threshold, the second switch S2 between the rectifier module and the energy storage and voltage stabilization module is disconnected, and the first switch S1 between the protection circuit and the current acquisition module is closed, thereby driving the current acquisition module to collect the alternating magnetic field of the wire, thereby realizing the function of collecting the wire current.

[0065] S500, the control module determines the current value of the wire according to the third signal through the control unit; Specifically, the current value of the wire is determined according to the third signal and the corresponding relationship between the third signal and the current value of the wire.

[0066] Furthermore, this step may also include comparing the voltage value of the third signal to determine whether the signal is caused by an interference signal such as noise, and adopting the current value of the wire determined by the third signal when the voltage value of the third signal is within a preset range.

[0067] S600, the control unit determines whether the current voltage drops to the third threshold value, and when the current voltage is lower than the third threshold value, drives the rectifier module to be electrically coupled with the energy storage and voltage stabilization module, and disconnects the protection module from the current acquisition module, so as to store the electric energy in the energy storage and voltage stabilization module again.

[0068] Specifically, this step is used to determine whether the power of the energy storage and voltage stabilization module is close to exhaustion. The control unit determines whether the current voltage drops to the third threshold, and when the current voltage is lower than the third threshold, it preliminarily determines that the power of the energy storage and voltage stabilization module is insufficient to power the energy storage and voltage stabilization module, and it is necessary to interrupt the current measurement work, and then charge the energy storage and voltage stabilization module, and convert the alternating magnetic field of the wire into electrical energy for storage.

[0069] It should be noted that the size of the third threshold is not limited here. This step can also be performed by controlling the power supply time of the energy storage and voltage stabilization module through the control unit, and when the power supply time exceeds the preset power supply time, driving the rectifier module to be electrically coupled with the energy storage and voltage stabilization module, and disconnecting the protection module from the current acquisition module, so as to store the electric energy in the energy storage and voltage stabilization module again.

[0070] In this step, the driving rectifier module is disconnected from the energy storage and voltage stabilizing module, and the protection module is electrically coupled to the current acquisition module. The preferred execution steps are: first, the driving protection module is electrically coupled to the current acquisition module, and then the driving rectifier module is disconnected from the energy storage and voltage stabilizing module.

[0071] To achieve the above object, an embodiment of the present invention further provides an electronic device, which includes a current sensor; the current sensor is the above current sensor, or a current sensor manufactured by the above current measurement method.

[0072] The electronic device of the embodiment of the present invention may also include loads such as electric lights and cameras, and the loads are powered by the energy storage and voltage stabilization module in the current sensor.

[0073] Therefore, compared with the prior art, the embodiments of the present invention have at least the following technical effects: The current sensor realizes the CT power supply and current measurement functions through the coordinated action of the mutual inductance module, protection module, current acquisition module, rectification module, energy storage voltage stabilization module and control module, while avoiding the repeated setting of the mutual inductance module and the protection module, which can greatly reduce the volume of the current sensor and reduce the equipment cost.

[0074] The above are only exemplary embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A current sensor, characterized in that: include: A mutual inductance module, used for sensing an alternating magnetic field generated by a conductor in the annular magnetic core, and outputting a first signal through a coil surrounding the annular magnetic core; A protection module, configured to output a second signal of the first signal that is lower than a first threshold; a current acquisition module, used for adjusting the voltage of the first resistor according to the second signal and outputting a third signal; A rectifier module, used for adjusting the second signal into a DC signal with a higher voltage; An energy storage and voltage stabilization module, used for storing the DC signal as electric energy with a stable voltage, and / or for supplying power to a control module; The control module is used to collect the current voltage of the energy storage and voltage stabilization module, determine the current of the wire according to the third signal, determine whether to drive the DC signal to be transmitted to the energy storage and voltage stabilization module according to the current voltage, and determine whether to drive the second signal to be transmitted to the current collection unit according to the current voltage.

2. The current sensor according to claim 1, characterized in that: The control module comprises: A first switch, located between the protection module and the current acquisition module, and used to control the coupling state between the protection module and the current acquisition module; A second switch, located between the rectifier module and the energy storage and voltage stabilization module, for controlling the coupling state of the rectifier module and the energy storage and voltage stabilization module; A voltage collection unit, electrically coupled to the energy storage and voltage stabilization module, for collecting the current voltage of the energy storage and voltage stabilization module; a current determining unit, electrically coupled to the current collecting unit, and configured to determine a current current of the wire according to the third signal; A control unit, configured to obtain the current voltage and the current current, drive the second switch and the first switch to be in an open state and a closed state respectively when the current voltage is higher than a second threshold value and determine the current current as the current value of the wire, and drive the second switch and the first switch to be in a closed state and an open state respectively when the current voltage drops to a third threshold value and stop determining the current current as the current value of the wire; The energy storage and voltage stabilization module is used to supply power to the voltage acquisition unit, the current determination unit and the control unit, and the supply voltage is a first voltage.

3. The current sensor according to claim 2, characterized in that: The first switch is a normally open field effect transistor, and the second switch is a normally closed field effect transistor; The control unit can further control the closing state of the first switch by adjusting the voltage of the first switch; The control unit can further control the closing state of the second switch by adjusting the voltage of the second switch.

4. The current sensor according to claim 2, characterized in that: The mutual inductance module includes the annular magnetic core and the coil; The coil is used to sense the alternating magnetic field generated by the alternating electric field in the conductor, and generate an induced electromotive force under the action of the alternating magnetic field; The coil is made of a high magnetic permeability material.

5. The current sensor according to claim 2, characterized in that: The protection module is used to monitor the voltage of the first signal and compare the voltage with the first threshold value, transmit the first signal to the discharge unit for release when the voltage is not lower than the first threshold value, and output the first signal to the rectifier module or the current acquisition module when the voltage is lower than the first threshold value.

6. The current sensor according to claim 2, characterized in that: The energy storage and voltage stabilization module comprises: an energy storage capacitor unit, electrically coupled to the output end of the rectifier module, and used to store the DC signal as electrical energy; A voltage stabilizing unit is electrically coupled to the energy storage capacitor unit and is used to adjust the output voltage of the energy storage voltage stabilizing module to at least one preset voltage; when the energy storage voltage stabilizing module supplies power to the control module, the preset voltage is the first voltage.

7. The current sensor according to claim 2, characterized in that: The control unit is used to perform the following steps in sequence when the current voltage is higher than the second threshold: driving the first switch to a closed state; driving the second switch to an off state; Acquire a third signal output by the current acquisition module; A current value of the wire is determined according to the third signal.

8. The current sensor according to claim 2, characterized in that: The control unit is used to perform the following steps in sequence when the current voltage is lower than a third threshold: driving the second switch to a closed state; The first switch is driven to be in an off state.

9. A current measurement method, using the current sensor according to any one of claims 1 to 8, characterized in that: The following steps are involved: The alternating magnetic field generated by the conductor in the annular magnetic core is sensed by a mutual inductance module, a protection module, a rectification module, and an energy storage and voltage stabilization module which are electrically coupled in sequence, and the electric energy with a stable voltage is stored in the energy storage and voltage stabilization module; Powering the control module through the energy storage and voltage stabilization module; Continuously collecting the current voltage of the energy storage and voltage stabilization module through the control module; The control module determines whether the current voltage is higher than a second threshold value, and when the current voltage is higher than the second threshold value, drives the rectifier module to disconnect from the energy storage and voltage stabilization module, and electrically couples the rectifier module to the current acquisition module, thereby sensing the current of the wire through the current acquisition module and outputting a third signal; The control module determines the current value of the wire according to the third signal through the control unit; The control unit determines whether the current voltage drops to a third threshold value, and when the current voltage is lower than the third threshold value, drives the rectifier module to disconnect from the energy storage and voltage stabilization module and electrically couples the rectifier module to the current acquisition module, so as to store electrical energy in the energy storage and voltage stabilization module again.

10. An electronic device, characterized in that: including a current sensor; The current sensor is the current sensor according to any one of claims 1 to 8, or a current sensor manufactured by the current measurement method according to claim 9.

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