Electricity stealing prevention circuit applied to electric energy meter and acquisition terminal product

Abstract

The embodiment of the invention discloses an electricity stealing prevention circuit applied to an electric energy meter and an acquisition terminal product, and the circuit comprises a magnetic field intensity detection module which is used for detecting the magnetic field intensity around the electric energy meter and outputting a magnetic field intensity detection signal; the signal amplification module is electrically connected with the magnetic field intensity detection module and is used for amplifying the magnetic field intensity detection signal and outputting a voltage amplification signal; the boosting module is electrically connected with the signal amplification module and is used for outputting a boosting signal according to the voltage amplification signal; and the load switch driving module is electrically connected with the boosting module and is used for outputting a tripping signal or a closing signal to a relay coil of the electric energy meter according to the boosting signal. By adopting the technical means, quantitative detection of the magnetic field intensity can be realized, and when an electricity stealing phenomenon occurs, brake-out control can be realized, and resource loss can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-theft electricity, and in particular to an anti-theft electricity circuit applied to electric energy meters and data collection terminal products. Background Art

[0002] As the demand for electricity increases, the requirements for the electricity environment also increase.

[0003] Magnetic field is a particularly prominent way of stealing electricity. In order to further improve the requirements of the electric energy meter's resistance to magnetic field, the current common practice is to add anti-magnetic plates to isolate magnetic field interference from the source, which can achieve the expected effect. However, due to the high cost and difficulty of the manufacturing process of thicker anti-magnetic plates, the same anti-magnetic conditions require a relatively high cost. At the same time, when the magnetic field strength reaches the critical conditions of the technical requirements, the electric energy meter will be negative or lost, and the load switch will not be able to operate, resulting in the electric energy meter being unable to switch off in time, causing the loss of power resources. Summary of the invention

[0004] The embodiment of the present invention provides an anti-theft power circuit applied to electric energy meters and data collection terminal products to achieve quantitative detection of magnetic field strength, and when power theft occurs, it can achieve power outage control and reduce resource loss.

[0005] The embodiment of the present invention provides an anti-theft power circuit applied to electric energy meters and data collection terminal products, including:

[0006] A magnetic field strength detection module is used to detect the magnetic field strength around the electric energy meter and output a magnetic field strength detection signal;

[0007] a signal amplification module, electrically connected to the magnetic field strength detection module, for amplifying the magnetic field strength detection signal and outputting a voltage amplification signal;

[0008] A boost module, electrically connected to the signal amplification module, and configured to output a boost signal according to the voltage amplification signal;

[0009] The load switch driving module is electrically connected to the boost module and is used to output a trip signal or a closing signal to the relay coil of the electric energy meter according to the boost signal.

[0010] Optionally, the anti-theft electrical circuit further comprises: an adjustment module;

[0011] The adjustment module is electrically connected to the output end of the signal amplification module and the input end of the boost module respectively, and is used for outputting an adjustment signal to the boost module according to the voltage amplification signal.

[0012] Optionally, the adjustment module includes: a first operational amplifier, a first resistor, a second resistor, a third resistor and a fourth resistor;

[0013] The first end of the first resistor is electrically connected to the output end of the signal amplification module, and the second end of the first resistor is electrically connected to the inverting input end of the first operational amplifier and the first end of the second resistor respectively; the second end of the second resistor is electrically connected to the output end of the first operational amplifier and the input end of the boost module respectively; the non-inverting input end of the first operational amplifier is electrically connected to the first end of the third resistor and the first end of the fourth resistor respectively; the second end of the third resistor is electrically connected to the power supply end; and the second end of the fourth resistor is grounded.

[0014] Optionally, the load switch driving module includes: a relay driving chip, a first current limiting protection resistor and a second current limiting protection resistor;

[0015] The output end of the boost module is electrically connected to the first power supply end of the relay driver chip and the second power supply end of the relay driver chip;

[0016] The first end of the relay coil is electrically connected to the first drive output end of the relay driver chip, and the second end of the relay coil is electrically connected to the second drive output end of the relay driver chip; the tripping signal input end of the relay driver chip is electrically connected to the tripping drive pin of the electric energy meter through the first current limiting protection resistor, and the closing signal input end of the relay driver chip is electrically connected to the closing drive pin of the electric energy meter through the second current limiting protection resistor.

[0017] Optionally, the magnetic field strength detection module includes: a detection chip, a first grounding capacitor, a second grounding capacitor, and a fifth resistor;

[0018] The power supply end of the detection chip is electrically connected to the power supply end and the first end of the first grounding capacitor respectively, and the second end of the first grounding capacitor is grounded;

[0019] The output end of the detection chip is electrically connected to the first end of the second grounding capacitor and the first end of the fifth resistor respectively, and the second end of the second grounding capacitor is grounded; the second end of the fifth resistor is electrically connected to the input end of the signal amplification module.

[0020] Optionally, the signal amplification module includes: a second operational amplifier, a sixth resistor, a seventh resistor and an eighth resistor;

[0021] The output end of the magnetic field strength detection module is electrically connected to the non-inverting input end of the second operational amplifier through the sixth resistor; the inverting input end of the second operational amplifier is electrically connected to the first end of the seventh resistor and the first end of the eighth resistor respectively; the second end of the seventh resistor is electrically connected to the output end of the second operational amplifier, and the second end of the eighth resistor is grounded.

[0022] Optionally, the boost module includes: the boost module includes: a conversion chip, a first diode, a second diode, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor and an inductor;

[0023] The output end of the signal amplification module is electrically connected to the anode of the first diode, the cathode of the first diode is electrically connected to the first end of the ninth resistor, the second end of the ninth resistor is electrically connected to the first end of the first capacitor, the first end of the tenth resistor, the first end of the eleventh resistor and the feedback end of the conversion chip respectively; the second end of the tenth resistor is grounded; the second end of the eleventh resistor is respectively connected to the cathode of the second diode, the second end of the first capacitor, the first end of the second capacitor, the first end of the third capacitor and the input end of the load switch driving module; the second end of the second capacitor and the second end of the third capacitor are both grounded; the anode of the second diode is respectively electrically connected to the switch output end of the conversion chip and the first end of the inductor; the second end of the inductor is respectively electrically connected to the first end of the twelfth resistor, the input end of the conversion chip, the first end of the fourth capacitor and the first end of the fifth capacitor; the second end of the twelfth resistor is electrically connected to the enable end of the conversion chip; the second end of the fourth capacitor and the second end of the fifth capacitor are both grounded.

[0024] Optionally, the first diode includes a first freewheeling diode; and the second diode includes a second freewheeling diode.

[0025] Optionally, the boost module further includes: an electrolytic capacitor;

[0026] The electrolytic capacitor is arranged in parallel at both ends of the third capacitor.

[0027] Optionally, the resistance value of the first current limiting protection resistor is less than or equal to 5KΩ; the resistance value of the second current limiting protection resistor is less than or equal to 5KΩ.

[0028] The technical solution provided by the embodiment of the present invention detects the magnetic field strength around the electric energy meter through a magnetic field strength detection module, and outputs a magnetic field strength detection signal to a signal amplification module. The signal amplification module amplifies the magnetic field strength detection signal to form a voltage amplification signal, and outputs the voltage amplification signal to a boost module. The boost module outputs a boost signal to a load switch drive module according to the voltage amplification signal to improve the driving ability of the electric energy meter relay coil, so as to achieve power outage control and reduce resource loss when power theft occurs. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of a first anti-theft power circuit applied to an electric energy meter and a data collection terminal product provided by an embodiment of the present invention;

[0030] Figure 2 A schematic diagram of the structure of a second anti-theft power circuit applied to electric energy meters and data collection terminal products provided by an embodiment of the present invention;

[0031] Figure 3 A schematic diagram of the electrical principle of an adjustment module provided by an embodiment of the present invention;

[0032] Figure 4 A schematic diagram of the electrical principle of a load switch driving module provided by an embodiment of the present invention;

[0033] Figure 5 A schematic diagram of the electrical principle of a magnetic field strength detection module provided by an embodiment of the present invention;

[0034] Figure 6 A schematic diagram of the electrical principle of a signal amplification module provided by an embodiment of the present invention;

[0035] Figure 7 A schematic diagram of the electrical principle of a boost module provided in an embodiment of the present invention;

[0036] Figure 8 The present invention provides an electrical principle diagram of an anti-theft power circuit applied to electric energy meters and data collection terminal products. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0038] Figure 1 The first embodiment of the present invention provides a schematic diagram of the structure of an anti-theft circuit for electric energy meters and data collection terminal products, such as Figure 1As shown, the anti-theft circuit applied to the electric energy meter and the data collection terminal product includes: a magnetic field strength detection module 10, which is used to detect the magnetic field strength around the electric energy meter and output a magnetic field strength detection signal; a signal amplification module 20, which is electrically connected to the magnetic field strength detection module 10, and is used to amplify the magnetic field strength detection signal and output a voltage amplification signal; a boost module 30, which is electrically connected to the signal amplification module 20, and is used to output a boost signal according to the voltage amplification signal; a load switch driving module 40, which is electrically connected to the boost module 30, and is used to output a trip signal or a closing signal to the relay coil of the electric energy meter according to the boost signal.

[0039] At present, there is a phenomenon of stealing electricity by influencing the meter's measurement with a strong magnetic field, causing it to under-measure or not measure electricity. A strong magnetic field will affect the current transformer and voltage transformer inside the meter, causing their magnetic circuit to saturate, and the output to decrease or even disappear, causing the meter to under-measure.

[0040] Specifically, the magnetic field strength detection module 10 provided in the embodiment of the present invention can detect the magnetic field strength around the electric energy meter, so as to realize the quantitative detection of the magnetic field strength. The magnetic field strength detection module 10 outputs the detected magnetic field strength detection signal to the signal amplification module 20, so that the signal amplification module 20 amplifies the magnetic field strength detection signal to generate a larger output voltage amplification signal, which is conducive to the subsequent processing of the magnetic field strength detection signal.

[0041] Furthermore, the signal amplification module 20 outputs a voltage amplification signal to the boost module 30, so that the boost module 30 can convert the low-voltage DC power supply input by the signal amplification module 20 into a high-voltage DC power supply, and then output a boost signal to the load switch driving module 40, so as to improve the driving ability of the relay coil of the electric energy meter. In this way, when the magnetic field strength detection module 10 detects that the magnetic field strength around the electric energy meter is strong, the magnetic field strength detection signal output by the magnetic field strength detection module 10 is processed by the signal amplification module 20 and the boost module 30 in turn and output to the load switch driving module 40. In this way, the load switch driving module 40 outputs a tripping signal to the relay coil of the electric energy meter, driving the relay coil to trip, thereby stopping the power supply. In this way, when power theft occurs, the power switch control can be achieved to reduce resource loss.

[0042] It should be noted that when the magnetic field strength detection module 10 detects that the magnetic field strength around the electric energy meter is weak, the magnetic field strength detection signal output by the magnetic field strength detection module 10 is processed by the signal amplification module 20 and the boost module 30 in turn and then output to the load switch driving module 40. In this way, the load switch driving module 40 outputs a closing signal to the relay coil of the electric energy meter. At this time, the relay coil does not need to be switched off, that is, there is no risk of electricity theft, and power supply continues to ensure the normal operation of the power system.

[0043] The anti-theft power circuit applied to the electric energy meter and the data collection terminal product provided by the embodiment of the present invention detects the magnetic field strength around the electric energy meter through the magnetic field strength detection module, and outputs the magnetic field strength detection signal to the signal amplification module. The signal amplification module amplifies the magnetic field strength detection signal to form a voltage amplification signal, and outputs the voltage amplification signal to the boost module. The boost module outputs the boost signal to the load switch driving module according to the voltage amplification signal to improve the driving ability of the relay coil of the electric energy meter, so as to realize the power switch control and reduce the resource loss when the power theft occurs.

[0044] Optional, Figure 2 A schematic diagram of the structure of a second anti-theft power circuit applied to an electric energy meter and a data collection terminal product provided by an embodiment of the present invention is shown in FIG. Figure 2 As shown, the anti-theft circuit also includes: an adjustment module 50; the adjustment module 50 is electrically connected to the output end of the signal amplification module 20 and the input end of the boost module 30 respectively, and is used to output an adjustment signal to the boost module 30 according to the voltage amplification signal.

[0045] Specifically, when the magnetic field strength detected by the magnetic field strength detection module 10 is larger, the corresponding voltage amplification signal output by the signal amplification module 20 is larger. Due to the feedback mechanism of the boost module 30, the voltage amplification signal needs to be pulled down and then input into the boost module 30, so that the boost module 30 can boost the input signal.

[0046] Specifically, the adjustment module 50 can be understood as a subtraction circuit, which can reduce the input voltage to the boost module 30 by subtracting the voltage amplification signal output by the signal amplification module from the external power supply signal, so that the boost module 30 can boost the voltage and improve the drive to the relay coil. The adjustment signal can be understood as the voltage signal after the voltage amplification signal output by the signal amplification module 20 is lowered by the adjustment module 50.

[0047] It should be noted that the external power signal is applied manually, and thus the voltage value of the external power signal can be set as required.

[0048] Optional, Figure 3 A schematic diagram of an electrical principle of an adjustment module provided by an embodiment of the present invention, such as Figure 3As shown, the adjustment module 50 includes: a first operational amplifier U1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4; the first end of the first resistor R1 is electrically connected to the output end of the signal amplification module, and the second end of the first resistor R1 is electrically connected to the inverting input end of the first operational amplifier U1 and the first end of the second resistor R2 respectively; the second end of the second resistor R2 is electrically connected to the output end OUT of the first operational amplifier U1 and the input end of the boost module respectively; the non-inverting input end of the first operational amplifier U1 is electrically connected to the first end of the third resistor R3 and the first end of the fourth resistor R4 respectively; the second end of the third resistor R3 is electrically connected to the power supply end VDD; the second end of the fourth resistor R4 is grounded.

[0049] Specifically, the output voltage V of the adjustment module 50 is OUT The relationship between the voltage V1 output from the output end of the signal amplifier module and the external voltage VDD is V OUT =VDD-V1, the adjustment module 50 is equivalent to a subtraction circuit, which can lower the input voltage to the boost module by subtracting the voltage amplification signal output by the signal amplification module from the external power supply signal, so that the boost module 30 can boost the voltage and improve the driving ability of the relay coil.

[0050] Specifically, the first resistor R1 and the third resistor R3 are respectively located at the inverting input terminal and the non-inverting input terminal of the first operational amplifier U1, so as to limit the current flowing into the input terminal of the first operational amplifier U1 and prevent the first operational amplifier U1 from being damaged by a large current.

[0051] Specifically, by setting the fourth resistor R4, on the one hand, the common mode signal can be reduced, and on the other hand, a stable reference potential can be provided to ensure that the operational amplifier can work normally.

[0052] Specifically, the second resistor R2 is a feedback resistor, which can reduce the sensitivity of the output of the first operational amplifier U1 to the input signal and stabilize the output, and can suppress temperature drift.

[0053] Optional, Figure 4 A schematic diagram of the electrical principle of a load switch driving module provided by an embodiment of the present invention is shown in FIG. Figure 4As shown, the load switch driving module 40 includes: a relay driving chip U2, a first current limiting protection resistor R20 and a second current limiting protection resistor R30; the output end of the boost module is electrically connected to the first power supply end VDD1 of the relay driving chip U2 and the second power supply end VDD2 of the relay driving chip U2; the first end of the relay coil 401 is electrically connected to the first drive output end OUTA of the relay driving chip U2, and the second end of the relay coil 401 is electrically connected to the second drive output end OUTB of the relay driving chip U2; the trip signal input end INB of the relay driving chip U2 is electrically connected to the trip drive pin of the electric energy meter through the first current limiting protection resistor R20, and the closing signal input end INA of the relay driving chip is electrically connected to the closing drive pin of the electric energy meter through the second current limiting protection resistor R30.

[0054] Specifically, the input end of the load switch driving module 40 is electrically connected to the output end of the boost module, that is, VDD1 and VDD2 of the relay driving chip U2 receive the voltage signal DC input from the output end of the boost module. The relay of the electric energy meter is equivalent to the load switch, and the two ends of the relay are equivalent to the two electrodes of the load switch. The trip signal is input by the trip signal input terminal INB, the closing signal is input by the closing signal input terminal INA, and is output to the relay coil by the first drive output terminal OUTA and the second drive output terminal OUTB, so that the relay coil can be controlled to be attracted or disconnected, and then the closing or tripping can be realized.

[0055] Exemplarily, when a high level is input to the trip signal input terminal INB, the two electrodes of the load switch will be reversed, and then the load switch will be disconnected, thereby tripping and stopping the power supply.

[0056] It should be noted that the relay driving chip U2 further includes two ground terminals GND, which are electrically connected to ground signals respectively.

[0057] It is understandable that a capacitor may be connected in series between the input terminal of the load switch driving module 40 and the ground signal, so that filtering and voltage stabilization can be achieved through the capacitor.

[0058] Optional, continue to refer to Figure 4 , the resistance value of the first current limiting protection resistor R20 is less than or equal to 5KΩ; the resistance value of the second current limiting protection resistor R30 is less than or equal to 5KΩ.

[0059] Specifically, the voltage of the load switch driving module 40 is generally 5V, and the resistance values ​​of the first current limiting protection resistor R20 and the second current limiting protection resistor R30 are both less than or equal to 5KΩ, which is conducive to ensuring the stability and reliability of the load switch driving module 40.

[0060] Optional, Figure 5A schematic diagram of the electrical principle of a magnetic field strength detection module provided by an embodiment of the present invention, such as Figure 5 As shown, the magnetic field strength detection module 10 includes: a detection chip U3, a first grounding capacitor C1, a second grounding capacitor C2, and a fifth resistor R5; the power supply terminal VDD of the detection chip U3 is electrically connected to the power supply terminal VCC and the first end of the first grounding capacitor C1, and the second end of the first grounding capacitor C1 is grounded; the output terminal OUT of the detection chip U3 is electrically connected to the first end of the second grounding capacitor C2 and the first end of the fifth resistor R5, and the second end of the second grounding capacitor C2 is grounded; the second end of the fifth resistor R5 is electrically connected to the input end of the signal amplification module.

[0061] Specifically, the power supply terminal VCC provides a working voltage for the detection chip U3 to ensure the normal operation of the magnetic field strength detection module 10. Exemplarily, the working voltage may be 3V-5.5V.

[0062] Specifically, by providing the first grounding capacitor C1 and the second grounding capacitor C2, it is possible to stabilize the power supply voltage, filter out noise, protect chip safety, enhance anti-interference capability, and improve electromagnetic compatibility.

[0063] Specifically, by disposing the fifth resistor R5 between the output terminal OUT of the detection chip U3 and the input terminal of the signal amplification module, a current limiting effect can be achieved, which is beneficial to ensuring the stability and safety of the output terminal OUT of the detection chip U3.

[0064] Optional, Figure 6 A schematic diagram of the electrical principle of a signal amplification module provided by an embodiment of the present invention is shown in FIG. Figure 6 As shown, the signal amplification module 20 includes: a second operational amplifier U4, a sixth resistor R6, a seventh resistor R7 and an eighth resistor R8; the output end of the magnetic field strength detection module is electrically connected to the positive input end of the second operational amplifier U4 through the sixth resistor R6; the inverting input end of the second operational amplifier U4 is electrically connected to the first end of the seventh resistor R7 and the first end of the eighth resistor R8 respectively; the second end of the seventh resistor R7 is electrically connected to the output end of the second operational amplifier U4, and the second end of the eighth resistor R8 is grounded.

[0065] Specifically, the output end of the magnetic field strength detection module is electrically connected to the non-inverting input end of the second operational amplifier U4 through the sixth resistor R6, so that the sixth resistor R6 can achieve current limiting effect to prevent the second operational amplifier U4 from being damaged due to a large current.

[0066] Specifically, negative feedback can be formed by setting the seventh resistor R7: the resistor provides a negative feedback path from the output terminal to the inverting input terminal, which is conducive to stabilizing the gain of the circuit and improving the stability of the circuit, and the negative feedback helps to reduce the sensitivity of the overall gain of the circuit to the change of the operational amplifier parameters, thereby improving the linearity and stability of the circuit. In addition, the eighth resistor R8 can improve the stability and anti-interference ability of the circuit.

[0067] Optional, Figure 7 A schematic diagram of the electrical principle of a boost module provided by an embodiment of the present invention is shown in FIG. Figure 7 As shown, the boost module 30 includes: a conversion chip U5, a first diode D1, a second diode D2, a first capacitor C11, a second capacitor C22, a third capacitor C33, a fourth capacitor C44, a fifth capacitor C55, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12 and an inductor L; the output end of the signal amplification module is electrically connected to the anode of the first diode D1, the cathode of the first diode D1 is electrically connected to the first end of the ninth resistor R9, the second end of the ninth resistor R9 is electrically connected to the first end of the first capacitor C11, the first end of the tenth resistor R10, the first end of the eleventh resistor R11 and the feedback end FB of the conversion chip U5 respectively; the second end of the tenth resistor R10 is grounded; the The second end is respectively connected to the cathode of the second diode D2, the second end of the first capacitor C11, the first end of the second capacitor C22, the first end of the third capacitor C33 and the input end of the load switch driving module; the second end of the second capacitor C22 and the second end of the third capacitor C33 are both grounded; the anode of the second diode D2 is respectively electrically connected to the switch output terminal SW of the conversion chip U4 and the first end of the inductor L; the second end of the inductor L is respectively electrically connected to the first end of the twelfth resistor R12, the input terminal IN of the conversion chip U5, the first end of the fourth capacitor C44 and the first end of the fifth capacitor C55; the second end of the twelfth resistor R12 is electrically connected to the enable terminal EN of the conversion chip U5; the second end of the fourth capacitor and the second end of the fifth capacitor are both grounded.

[0068] Specifically, the switch output terminal SW outputs a switch signal. When the switch output terminal SW outputs a close signal, the input voltage is input by the anode of the first diode D1, and the load is powered through the inductor L, and the electric energy is stored in the inductor L. The current in the inductor L increases linearly over time, and the inductor L stores energy. When the switch output terminal SW outputs an open signal, the energy stored in the inductor L is transferred to the capacitor C11, and the capacitor C11 starts to charge to maintain the stability of the output voltage. When the switch output terminal SW outputs a close signal again, the inductor L accumulates energy again. This process is periodic. By adjusting the duty cycle of the pulse width modulation signal, the amount of energy stored and released by the inductor L can be controlled, thereby adjusting the output voltage. In other words, the boost module 30 stores energy through the inductor, and then releases the energy to the output terminal when the switch is closed, thereby increasing the output voltage.

[0069] Optional, continue to refer to Figure 7 The first diode D1 includes a first freewheeling diode; the second diode D2 includes a second freewheeling diode.

[0070] Specifically, the first diode D1 and the second diode D2 are both freewheeling diodes, so when the current of the inductive load changes or decreases suddenly, a sudden voltage will be generated at both ends of the inductor, which may damage other electronic components. In the boost circuit, the freewheeling diode provides a path so that the energy stored in the inductor can be released to maintain the current continuity in the circuit and prevent the reverse electromotive force generated by the sudden current from damaging the switching devices in the circuit. Therefore, the freewheeling diode plays a role of protection and energy release in the boost module 30.

[0071] Optional, continue to refer to Figure 7 The boost module 30 further includes: an electrolytic capacitor C; the electrolytic capacitor C is arranged in parallel at both ends of the third capacitor C33.

[0072] Specifically, the electrolytic capacitor C has filtering and decoupling functions, which are beneficial to ensuring the stability and reliability of the boost circuit 30 .

[0073] Figure 8 The electrical principle diagram of an anti-theft power circuit applied to an electric energy meter and a collection terminal product provided by an embodiment of the present invention is as follows: Figure 8As shown, the anti-theft power circuit includes a magnetic field strength detection module 10, a signal amplification module 20, an adjustment module 50, a boost module 30 and a load switch driving module 40. The magnetic field strength detection module 10 outputs the detected magnetic field strength detection signal to the signal amplification module 20 for signal amplification, and outputs the voltage amplification signal to the adjustment module 50, and outputs the adjustment signal to the boost module 30 after subtraction calculation, so that the boost module 30 can boost the input voltage signal, thereby improving the driving ability of the composite switch, thereby realizing the switch-off operation under abnormal interference conditions and reducing the loss of power resources. In addition, the anti-theft power circuit has a gradual boost function and realizes step measurement control, which helps managers to master the power usage environment and improve power safety. The circuit automatically adjusts the closed-loop control throughout the process without the participation of software programs, and has higher reliability.

[0074] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An anti-theft power circuit applied to electric energy meters and collection terminal products, characterized in that: include: A magnetic field strength detection module is used to detect the magnetic field strength around the electric energy meter and output a magnetic field strength detection signal; a signal amplification module, electrically connected to the magnetic field strength detection module, for amplifying the magnetic field strength detection signal and outputting a voltage amplification signal; A boost module, electrically connected to the signal amplification module, and configured to output a boost signal according to the voltage amplification signal; The load switch driving module is electrically connected to the boost module and is used to output a trip signal or a closing signal to the relay coil of the electric energy meter according to the boost signal.

2. The anti-theft electrical circuit according to claim 1, characterized in that: The anti-theft electrical circuit also includes: an adjustment module; The adjustment module is electrically connected to the output end of the signal amplification module and the input end of the boost module respectively, and is used for outputting an adjustment signal to the boost module according to the voltage amplification signal.

3. The anti-theft electrical circuit according to claim 2, characterized in that: The adjustment module includes: a first operational amplifier, a first resistor, a second resistor, a third resistor and a fourth resistor; The first end of the first resistor is electrically connected to the output end of the signal amplification module, and the second end of the first resistor is electrically connected to the inverting input end of the first operational amplifier and the first end of the second resistor respectively; the second end of the second resistor is electrically connected to the output end of the first operational amplifier and the input end of the boost module respectively; the non-inverting input end of the first operational amplifier is electrically connected to the first end of the third resistor and the first end of the fourth resistor respectively; the second end of the third resistor is electrically connected to the power supply end; and the second end of the fourth resistor is grounded.

4. The anti-theft electrical circuit according to claim 1, characterized in that: The load switch driving module includes: a relay driving chip, a first current limiting protection resistor and a second current limiting protection resistor; The output end of the boost module is electrically connected to the first power supply end of the relay driver chip and the second power supply end of the relay driver chip; The first end of the relay coil is electrically connected to the first drive output end of the relay driver chip, and the second end of the relay coil is electrically connected to the second drive output end of the relay driver chip; the tripping signal input end of the relay driver chip is electrically connected to the tripping drive pin of the electric energy meter through the first current limiting protection resistor, and the closing signal input end of the relay driver chip is electrically connected to the closing drive pin of the electric energy meter through the second current limiting protection resistor.

5. The anti-theft electrical circuit according to claim 1, characterized in that: The magnetic field strength detection module includes: a detection chip, a first grounding capacitor, a second grounding capacitor, and a fifth resistor; The power supply end of the detection chip is electrically connected to the power supply end and the first end of the first grounding capacitor respectively, and the second end of the first grounding capacitor is grounded; The output end of the detection chip is electrically connected to the first end of the second grounding capacitor and the first end of the fifth resistor respectively, and the second end of the second grounding capacitor is grounded; the second end of the fifth resistor is electrically connected to the input end of the signal amplification module.

6. The anti-theft electrical circuit according to claim 1, characterized in that: The signal amplification module includes: a second operational amplifier, a sixth resistor, a seventh resistor and an eighth resistor; The output end of the magnetic field strength detection module is electrically connected to the non-inverting input end of the second operational amplifier through the sixth resistor; the inverting input end of the second operational amplifier is electrically connected to the first end of the seventh resistor and the first end of the eighth resistor respectively; the second end of the seventh resistor is electrically connected to the output end of the second operational amplifier, and the second end of the eighth resistor is grounded.

7. The anti-theft electrical circuit according to claim 1, characterized in that: The boost module includes: a conversion chip, a first diode, a second diode, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a fifth capacitor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor and an inductor; The output end of the signal amplification module is electrically connected to the anode of the first diode, the cathode of the first diode is electrically connected to the first end of the ninth resistor, the second end of the ninth resistor is electrically connected to the first end of the first capacitor, the first end of the tenth resistor, the first end of the eleventh resistor and the feedback end of the conversion chip respectively; the second end of the tenth resistor is grounded; the second end of the eleventh resistor is respectively connected to the cathode of the second diode, the second end of the first capacitor, the first end of the second capacitor, the first end of the third capacitor and the input end of the load switch driving module; the second end of the second capacitor and the second end of the third capacitor are both grounded; the anode of the second diode is respectively electrically connected to the switch output end of the conversion chip and the first end of the inductor; the second end of the inductor is respectively electrically connected to the first end of the twelfth resistor, the input end of the conversion chip, the first end of the fourth capacitor and the first end of the fifth capacitor; the second end of the twelfth resistor is electrically connected to the enable end of the conversion chip; the second end of the fourth capacitor and the second end of the fifth capacitor are both grounded.

8. The anti-theft electrical circuit according to claim 7, characterized in that: The first diode includes a first freewheeling diode; the second diode includes a second freewheeling diode.

9. The anti-theft electrical circuit according to claim 7, characterized in that: The boost module further includes: an electrolytic capacitor; The electrolytic capacitor is arranged in parallel at both ends of the third capacitor.

10. The anti-theft electrical circuit according to claim 4, characterized in that: The resistance value of the first current limiting protection resistor is less than or equal to 5KΩ; the resistance value of the second current limiting protection resistor is less than or equal to 5KΩ.

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