Power transmission line current-carrying capability safety monitoring circuit

Abstract

The invention discloses a power transmission line current-carrying capability safety monitoring circuit, and relates to the technical field of power transmission lines, and the circuit comprises a current sampling module which is used for carrying out the current sampling and signal processing of a power transmission line module; the electricity taking adjusting module is used for electricity taking processing; the signal comparison module is used for comparing the sampled voltage signal with a first current-carrying threshold value; the temperature detection module is used for carrying out temperature detection on the environment and the power transmission line and detecting the environment temperature and the temperature state of the power transmission line; the adjusting processing module is used for detecting whether an over-temperature condition does not exceed a current-carrying threshold value; the intelligent control module is used for signal receiving and module control; the current-carrying threshold module is used for setting and adjusting a first current-carrying threshold; and the change detection module is used for detecting the variable quantity of the current-carrying threshold value. The safety monitoring circuit for the current-carrying capacity of the power transmission line can accurately detect the current-carrying capacity of the power transmission line, so that the overheating condition of the power transmission line is avoided, and the safety of the power transmission line is improved.

Description

Technical Field

[0001] The invention relates to the technical field of power transmission lines, in particular to a current-carrying capacity safety monitoring circuit for power transmission lines. Background Art

[0002] As an indispensable part of the operation of the power grid, the transmission line is the carrier of electric energy transmission. In order to ensure the safe, stable and efficient operation of the transmission line, the current carrying capacity of the transmission line will be monitored. The current carrying capacity safety monitoring circuit of the transmission line in the prior art generally adopts relevant current carrying detection equipment to detect the current carrying capacity and temperature of the transmission line, and judge the voltage relationship between the current carrying capacity of the transmission line and the set maximum current carrying threshold, and then detect the current carrying capacity of the output transmission line. However, the current carrying capacity of the transmission line is easily affected by the external temperature, resulting in the inability to accurately detect the current carrying capacity of the transmission line. In addition, the long-term transmission of electric energy in the transmission line is likely to cause the current carrying capacity to decrease, and the current carrying detection equipment cannot adjust the set maximum current carrying threshold in time, resulting in overheating of the transmission line, so it needs to be improved. Summary of the invention

[0003] The embodiment of the present invention provides a transmission line current carrying capacity safety monitoring circuit to solve the problems raised in the above background technology.

[0004] According to an embodiment of the present invention, a transmission line current carrying capacity safety monitoring circuit is provided, comprising: a transmission line module, a current sampling module, a power taking adjustment module, a signal comparison module, a temperature detection module, an intelligent control module, an adjustment processing module, a current carrying threshold module and a change detection module;

[0005] Transmission line module, used for electric energy transmission;

[0006] A current sampling module, connected to the power transmission line module, for current sampling of the electric energy transmitted by the power transmission line module and outputting a sampling signal, converting, amplifying and filtering the sampling signal and outputting a voltage signal;

[0007] A power taking regulation module, connected to the intelligent control module and the current sampling module, for, when receiving the power taking signal output by the intelligent control module, rectifying the sampling signal and storing the processed electric energy, releasing the stored electric energy and performing voltage stabilization on the released electric energy, and outputting the first electric energy;

[0008] A signal comparison module, connected to the current carrying threshold module and the current sampling module, for outputting a first potential signal when the voltage signal is greater than a first current carrying threshold set by the current carrying threshold module, and outputting a second potential signal when the voltage signal is less than the first current carrying threshold;

[0009] A temperature detection module, connected to the power extraction module, used to set a maximum temperature threshold, a minimum temperature threshold and a voltage threshold, perform temperature detection on the environment and the transmission line respectively and output a first detection signal and a second detection signal, output a first control signal when the first detection signal is less than the maximum temperature threshold and greater than the minimum temperature threshold, calculate the difference between the second detection signal and the maximum temperature threshold and output a first difference signal, and output a second control signal when the first difference signal is greater than the voltage threshold;

[0010] an adjustment processing module, connected to the temperature detection module and the signal comparison module, configured to perform high-level self-locking when receiving the second control signal and the second potential signal and output a third potential signal when receiving the first control signal, and output a fourth potential signal when outputting the third potential signal and receiving the first potential signal;

[0011] An intelligent control module, connected to the temperature detection module, the adjustment processing module, the current sampling module and the change detection module, for outputting a power-taking signal when the current detection is stopped or the voltage signal is greater than the sampling threshold, outputting a first adjustment signal and a second adjustment signal, and adjusting the duty cycle of the first adjustment signal when receiving a third potential signal or outputting a power-taking signal, and maintaining the duty cycle of the first adjustment signal when receiving a fourth potential signal, and receiving a voltage signal, a first difference signal, a second difference signal output by the change detection module, and a first potential signal;

[0012] A current carrying threshold module, connected to the intelligent control module, for receiving the first electric energy and the first adjustment signal and setting the first current carrying threshold, and reducing the voltage value of the first current carrying threshold when receiving the first difference signal;

[0013] The change detection module is connected to the current carrying threshold module, and is used to receive the second adjustment signal and set the second current carrying threshold, perform subtraction processing on the second current carrying threshold and the first current carrying threshold, and output a second difference signal.

[0014] As a further solution of the present invention: the power transmission line module includes a power port and an output port; the current sampling module includes a first mutual inductor, a first resistor, a first capacitor and a signal processing device; the intelligent control module includes a first controller;

[0015] Preferably, the power port passes through the center of the first transformer and is connected to the output port, the first output end of the first transformer is connected to one end of the first resistor and the first input end of the signal processing device and is connected to the other end of the first resistor, the second input end of the signal processing device, the second output end of the first transformer and the ground through the first capacitor, and the output end of the signal processing device is connected to the IO2 end of the first controller and the signal comparison module.

[0016] As a further solution of the present invention: the signal comparison module includes a first comparator and a first inverter; the current carrying threshold module includes an eleventh resistor, a twelfth resistor, a first power tube, a thirteenth resistor, a first switch tube and a fourteenth resistor;

[0017] Preferably, the in-phase end of the first comparator is connected to the output end of the signal processing device, the inverting end of the first comparator is connected to the source of the first power tube and connected to the emitter and the ground end of the first switching tube through a thirteenth resistor, the drain of the first power tube is connected to the power adjustment module and the first end of the twelfth resistor through an eleventh resistor, the second end of the twelfth resistor is connected to the collector of the first switching tube, the gate of the first power tube and the IO4 end of the first controller, the base of the first switching tube is connected to the first end of the fourteenth resistor, the second end of the fourteenth resistor is connected to the temperature detection module, the output end of the first comparator is connected to the IO5 end of the first controller and the input end of the first inverter, and the output end of the first inverter is connected to the adjustment processing module.

[0018] As a further solution of the present invention: the temperature detection module includes a first thermistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a second comparator, a third comparator and a first logic chip;

[0019] Preferably, the first end of the first thermistor is connected to one end of the third resistor and the power taking regulation module and is connected to the first end of the sixth resistor and the non-inverting end of the second comparator through the fifth resistor, the other end of the third resistor is connected to the inverting end of the third comparator and one end of the fourth resistor, the other end of the fourth resistor is connected to the second end of the sixth resistor, one end of the second resistor and the ground, the other end of the second resistor is connected to the inverting end of the second comparator, the non-inverting end of the third comparator and the second end of the first thermistor, the output end of the third comparator and the output end of the second comparator are respectively connected to the B end and the A end of the first logic chip, and the Y end of the first logic chip is connected to the regulation processing module.

[0020] As a further solution of the present invention: the temperature detection module further includes a second thermistor, a seventh resistor, a first subtraction device, a tenth resistor and a first diode;

[0021] Preferably, the first end of the second thermistor is connected to the first end of the first thermistor, the second end of the second thermistor is connected to the first input end of the first subtraction device and is grounded through the seventh resistor, the second input end of the first subtraction device is connected to the first end of the sixth resistor, the output end of the first subtraction device is connected to the second end of the fourteenth resistor and the IO3 end of the first controller and is connected to the cathode of the first diode through the tenth resistor, and the anode of the first diode is connected to the regulation processing module.

[0022] As a further solution of the present invention: the power taking and regulating module includes a first thyristor, a first rectifier, an energy storage device and a voltage stabilizing device;

[0023] Preferably, one end of the first thyristor is connected to the first output end of the first mutual inductor, the other end of the first thyristor is connected to the first end of the first rectifier, the second end of the first rectifier is connected to the second output end of the first mutual inductor, the third end of the first rectifier is connected to one end of the energy storage device and the input end of the voltage stabilizing device, the output end of the voltage stabilizing device is connected to the first end of the first thermistor and the first end of the twelfth resistor, and the ground end of the voltage stabilizing device is connected to the other end of the energy storage device, the fourth end of the first rectifier and the ground end.

[0024] As a further solution of the present invention: the adjustment processing module includes a second diode, a third diode, a fourth diode, a second logic chip, a fourth logic chip and a third logic chip;

[0025] Preferably, the anode of the second diode is connected to the anode of the first diode, the cathode of the second diode is connected to the B end of the second logic chip and the cathode of the third diode, the anode of the third diode is connected to the Y end of the second logic chip, the anode of the fourth diode and the A end of the fourth logic chip, the A end of the second logic chip is connected to the output end of the first inverter and the cathode of the fourth diode, the Y end of the fourth logic chip is connected to the IO6 end of the first controller and the B end of the third logic chip, the A end of the third logic chip is connected to the input end of the first inverter, the Y end of the third logic chip is connected to the IO7 end of the first controller, and the B end of the fourth logic chip is connected to the Y end of the first logic chip.

[0026] As a further solution of the present invention: the change detection module includes a fifteenth resistor, an eighth resistor, a ninth resistor, a second power tube and a second subtraction device;

[0027] Preferably, one end of the fifteenth resistor is connected to the output end of the voltage stabilizing device and is connected to the drain of the second power tube through the eighth resistor, the source of the second power tube is connected to the first input end of the second subtraction device and is grounded through the ninth resistor, the output end of the second subtraction device is connected to the IO9 end of the first controller, the gate of the second power tube is connected to the other end of the fifteenth resistor and the IO8 end of the first controller, and the second input end of the second subtraction device is connected to the source of the first power tube.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: the transmission line current carrying capacity safety monitoring circuit of the present invention can detect the voltage size of the signal sampled by the current sampling module and the current carrying threshold set by the current carrying threshold module by the signal comparison module, and then detect the current carrying degree of the transmission line, and the power taking adjustment module performs energy storage and energy-saving power supply, and the temperature detection module performs temperature detection on the ambient temperature and the transmission line. When the external ambient temperature is within a certain temperature range, the intelligent control module automatically adjusts the voltage size of the current carrying threshold through the temperature state of the transmission line and the detection result of the signal comparison module, and at the same time, the temperature detection module fine-tunes the current carrying threshold so as to accurately detect the current carrying capacity of the transmission line, avoid overheating of the transmission line, and improve the safety of the transmission line. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0030] Figure 1 A schematic block diagram of a power transmission line current carrying capacity safety monitoring circuit provided in an embodiment of the present invention.

[0031] Figure 2 A circuit diagram of a transmission line current carrying capacity safety monitoring circuit provided in an embodiment of the present invention.

[0032] Figure 3 A circuit diagram of an adjustment processing module provided in an embodiment of the present invention.

[0033] Figure 4 A circuit diagram of a change detection module provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] 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.

[0035] In one embodiment, see Figure 1 , a transmission line current carrying capacity safety monitoring circuit, comprising: a transmission line module 1, a current sampling module 2, a power taking adjustment module 3, a signal comparison module 4, a temperature detection module 5, an intelligent control module 6, an adjustment processing module 7, a current carrying threshold module 8 and a change detection module 9;

[0036] Specifically, the power transmission line module 1 is used for power transmission;

[0037] The current sampling module 2 is connected to the power transmission line module 1, and is used to perform current sampling on the electric energy transmitted by the power transmission line module 1 and output a sampling signal, convert and amplify the sampling signal and filter it and output a voltage signal;

[0038] The power taking regulation module 3 is connected to the intelligent control module 6 and the current sampling module 2, and is used for rectifying the sampling signal and storing the processed electric energy when receiving the power taking signal output by the intelligent control module 6, releasing the stored electric energy and performing voltage stabilization on the released electric energy, and outputting the first electric energy;

[0039] The signal comparison module 4 is connected to the current carrying threshold module 8 and the current sampling module 2, and is used to output a first potential signal when the voltage signal is greater than a first current carrying threshold set by the current carrying threshold module 8, and output a second potential signal when the voltage signal is less than the first current carrying threshold;

[0040] A temperature detection module 5 is connected to the power taking module, and is used to set a maximum temperature threshold, a minimum temperature threshold, and a voltage threshold, and to perform temperature detection on the environment and the power transmission line respectively and output a first detection signal and a second detection signal. When the first detection signal is less than the maximum temperature threshold and greater than the minimum temperature threshold, a first control signal is output, and a difference between the second detection signal and the maximum temperature threshold is calculated and a first difference signal is output. When the first difference signal is greater than the voltage threshold, a second control signal is output;

[0041] The adjustment processing module 7 is connected to the temperature detection module 5 and the signal comparison module 4, and is used to perform high-level self-locking when receiving the second control signal and the second potential signal, and output the third potential signal when receiving the first control signal, and output the fourth potential signal when outputting the third potential signal and receiving the first potential signal;

[0042] The intelligent control module 6 is connected to the temperature detection module 5, the adjustment processing module 7, the current sampling module 2 and the change detection module 9, and is used to output a power-taking signal when the current detection is stopped or the voltage signal is greater than the sampling threshold, output a first adjustment signal and a second adjustment signal, and adjust the duty cycle of the first adjustment signal when receiving a third potential signal or outputting a power-taking signal, and maintain the duty cycle of the first adjustment signal when receiving a fourth potential signal, and receive a voltage signal, a first difference signal, a second difference signal and a first potential signal output by the change detection module 9;

[0043] A current carrying threshold module 8, connected to the intelligent control module 6, for receiving the first electric energy and the first adjustment signal and setting the first current carrying threshold, and reducing the voltage value of the first current carrying threshold when receiving the first difference signal;

[0044] The change detection module 9 is connected to the current carrying threshold module 8, and is used to receive the second adjustment signal and set the second current carrying threshold, perform subtraction processing on the second current carrying threshold and the first current carrying threshold, and output a second difference signal.

[0045] In a specific embodiment, the above-mentioned transmission line module 1 can use a transmission line circuit composed of a power port, a transmission line and an output port to perform power transmission; the above-mentioned current sampling module 2 can use a current sampling circuit composed of a current transformer, a resistor, a signal processing device, etc., which can perform current sampling on the electric energy transmitted by the transmission line and convert, amplify and filter the sampled signal to output a voltage signal; the above-mentioned power adjustment module 3 can use a power adjustment circuit composed of a thyristor, a rectifier, an energy storage device and a voltage stabilizing device, which can rectify and store the signal sampled by the current sampling module 2, and output a voltage signal. The stored electric energy is subjected to voltage stabilization discharge processing; the signal comparison module 4 can adopt a signal comparison circuit composed of a comparator and an inverter, which can perform voltage comparison and signal inversion processing on the input signal; the temperature detection module 5 can adopt a temperature detection circuit composed of a thermistor, a resistor, a comparator, a subtraction device, etc., which can detect the ambient temperature and the temperature of the transmission line, and set the maximum temperature threshold, the minimum temperature threshold and the voltage threshold, compare the voltage size of the ambient temperature with the maximum temperature threshold and the minimum temperature threshold, and calculate the difference between the temperature and the voltage threshold of the transmission line, wherein the maximum temperature threshold and the minimum temperature threshold are respectively the maximum temperature and the minimum temperature of the first current threshold initially set, and the voltage threshold is the over-temperature limit of the transmission line; the intelligent control module 6 can adopt an intelligent control circuit composed of a single-chip microcomputer, which integrates many components such as an arithmetic unit, a controller, a memory, and an input and output device to realize signal processing, data storage, module control, timing control and other functions; the adjustment processing module 7 can adopt an adjustment processing circuit composed of a logic chip and a diode, which can perform logical calculations, and when the transmission line is overheated but the signal comparison module 4 does not detect an overcurrent, a high current is performed. The above-mentioned current-carrying threshold module 8 can adopt a current-carrying threshold device composed of a resistor, a field effect transistor and a triode, and can be adjusted and controlled by the intelligent control module 6 to set a first current-carrying threshold, and the first current-carrying threshold is the maximum current-carrying capacity of the transmission line; the above-mentioned change detection module 9 can adopt a change detection circuit composed of a field effect transistor, a resistor and a subtraction device, and can set a second current-carrying threshold, so as to compare the voltage difference between the first current-carrying threshold and the second current-carrying threshold, and the second current-carrying threshold is equal to the first current-carrying threshold set initially.

[0046] In another embodiment, see Figure 1 , Figure 2 , Figure 3 and Figure 4 , the power transmission line module 1 includes a power port and an output port; the current sampling module 2 includes a first transformer CT1, a first resistor R1, a first capacitor C1 and a signal processing device; the intelligent control module 6 includes a first controller U1;

[0047] Specifically, the power port passes through the center of the first transformer CT1 and is connected to the output port, the first output end of the first transformer CT1 is connected to one end of the first resistor R1 and the first input end of the signal processing device and is connected to the other end of the first resistor R1, the second input end of the signal processing device, the second output end of the first transformer CT1 and the ground end through the first capacitor C1, and the output end of the signal processing device is connected to the IO2 end of the first controller U1 and the signal comparison module 4.

[0048] In a specific embodiment, the power port and the output port are connected via a transmission line; the first transformer CT1 may be a current transformer; the signal processing device may be composed of an operational amplifier, a resistor and a capacitor to perform signal conversion, amplification and filtering; the first controller U1 may be an STM32 microcontroller.

[0049] Further, the signal comparison module 4 includes a first comparator A1 and a first inverter INV1; the current threshold module 8 includes an eleventh resistor R11, a twelfth resistor R12, a first power tube Q1, a thirteenth resistor R13, a first switch tube V1 and a fourteenth resistor R14;

[0050] Specifically, the in-phase end of the first comparator A1 is connected to the output end of the signal processing device, the inverting end of the first comparator A1 is connected to the source of the first power tube Q1 and connected to the emitter and the ground end of the first switch tube V1 through the thirteenth resistor R13, the drain of the first power tube Q1 is connected to the power adjustment module 3 and the first end of the twelfth resistor R12 through the eleventh resistor R11, the second end of the twelfth resistor R12 is connected to the collector of the first switch tube V1, the gate of the first power tube Q1 and the IO4 end of the first controller U1, the base of the first switch tube V1 is connected to the first end of the fourteenth resistor R14, the second end of the fourteenth resistor R14 is connected to the temperature detection module 5, the output end of the first comparator A1 is connected to the IO5 end of the first controller U1 and the input end of the first inverter INV1, and the output end of the first inverter INV1 is connected to the adjustment processing module 7.

[0051] In a specific embodiment, the first comparator A1 can be an LM358 comparator; the first inverter INV1 can be a NOT gate chip; the first power tube Q1 can be an N-channel field effect tube, which is controlled by the first adjustment signal output from the IO4 terminal of the first controller U1, and the first current carrying threshold is set in cooperation with the eleventh resistor R11, the twelfth resistor R12 and the thirteenth resistor R13; the first switch tube V1 can be an NPN transistor to fine-tune the first current carrying threshold.

[0052] Further, the temperature detection module 5 includes a first thermistor RT1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a second comparator A2, a third comparator A3 and a first logic chip J1;

[0053] Specifically, a first end of the first thermistor RT1 is connected to one end of the third resistor R3 and the power taking adjustment module 3 and is connected to a first end of the sixth resistor R6 and a non-inverting end of the second comparator A2 through a fifth resistor R5; the other end of the third resistor R3 is connected to an inverting end of the third comparator A3 and one end of the fourth resistor R4; the other end of the fourth resistor R4 is connected to a second end of the sixth resistor R6, one end of the second resistor R2 and a ground end; the other end of the second resistor R2 is connected to an inverting end of the second comparator A2, a non-inverting end of the third comparator A3 and a second end of the first thermistor RT1; the output end of the third comparator A3 and the output end of the second comparator A2 are respectively connected to the B end and the A end of the first logic chip J1; and the Y end of the first logic chip J1 is connected to the adjustment processing module 7.

[0054] In a specific embodiment, the first thermistor RT1 can be a negative temperature coefficient thermistor to detect the ambient temperature; the third resistor R3 and the fourth resistor R4 set the minimum temperature threshold, and the fifth resistor R5 and the sixth resistor R6 set the maximum temperature threshold; the second comparator A2 and the third comparator A3 can both be LM358 comparators; the first logic chip J1 can be an AND gate chip.

[0055] Further, the temperature detection module 5 also includes a second thermistor RT2, a seventh resistor R7, a first subtraction device, a tenth resistor R10 and a first diode D1;

[0056] Specifically, the first end of the second thermistor RT2 is connected to the first end of the first thermistor RT1, the second end of the second thermistor RT2 is connected to the first input end of the first subtraction device and is grounded through the seventh resistor R7, the second input end of the first subtraction device is connected to the first end of the sixth resistor R6, the output end of the first subtraction device is connected to the second end of the fourteenth resistor R14 and the IO3 end of the first controller U1 and is connected to the cathode of the first diode D1 through the tenth resistor R10, and the anode of the first diode D1 is connected to the adjustment processing module 7.

[0057] In a specific embodiment, the first subtraction device may be composed of an operational amplifier and a resistor, and the signal input to the first input terminal of the first subtraction device is replaced by the signal input to the second input terminal of the first subtraction device to obtain a first difference signal.

[0058] Furthermore, the power taking and regulating module 3 includes a first thyristor S1, a first rectifier T1, an energy storage device and a voltage stabilizing device;

[0059] Specifically, one end of the first thyristor S1 is connected to the first output end of the first transformer CT1, the other end of the first thyristor S1 is connected to the first end of the first rectifier T1, the second end of the first rectifier T1 is connected to the second output end of the first transformer CT1, the third end of the first rectifier T1 is connected to one end of the energy storage device and the input end of the voltage stabilizing device, the output end of the voltage stabilizing device is connected to the first end of the first thermistor RT1 and the first end of the twelfth resistor R12, and the ground end of the voltage stabilizing device is connected to the other end of the energy storage device, the fourth end of the first rectifier T1 and the ground end.

[0060] In a specific embodiment, the first thyristor S1 can be a bidirectional thyristor; the energy storage device can be a lithium battery; and the voltage stabilizing device can be a LM317 voltage stabilizer.

[0061] Further, the adjustment processing module 7 includes a second diode D2, a third diode D3, a fourth diode D4, a second logic chip J2, a fourth logic chip J4 and a third logic chip J3;

[0062] Specifically, the anode of the second diode D2 is connected to the anode of the first diode D1, the cathode of the second diode D2 is connected to the B terminal of the second logic chip J2 and the cathode of the third diode D3, the anode of the third diode D3 is connected to the Y terminal of the second logic chip J2, the anode of the fourth diode D4 and the A terminal of the fourth logic chip J4, the A terminal of the second logic chip J2 is connected to the output terminal of the first inverter INV1 and the cathode of the fourth diode D4, the Y terminal of the fourth logic chip J4 is connected to the IO6 terminal of the first controller U1 and the B terminal of the third logic chip J3, the A terminal of the third logic chip J3 is connected to the input terminal of the first inverter INV1, the Y terminal of the third logic chip J3 is connected to the IO7 terminal of the first controller U1, and the B terminal of the fourth logic chip J4 is connected to the Y terminal of the first logic chip J1.

[0063] In a specific embodiment, the second logic chip J2, the third logic chip J3 and the fourth logic chip J4 can all be AND gate chips, wherein the second logic chip J2 cooperates with the second diode D2, the fourth diode D4 and the third diode D3 to perform high level self-locking.

[0064] Further, the change detection module 9 includes a fifteenth resistor R15, an eighth resistor R8, a ninth resistor R9, a second power tube Q2 and a second subtraction device;

[0065] Specifically, one end of the fifteenth resistor R15 is connected to the output end of the voltage stabilizing device and is connected to the drain of the second power tube Q2 through the eighth resistor R8, the source of the second power tube Q2 is connected to the first input end of the second subtraction device and is grounded through the ninth resistor R9, the output end of the second subtraction device is connected to the IO9 end of the first controller U1, the gate of the second power tube Q2 is connected to the other end of the fifteenth resistor R15 and the IO8 end of the first controller U1, and the second input end of the second subtraction device is connected to the source of the first power tube Q1.

[0066] In a specific embodiment, the second power tube Q2 can be an N-channel field effect tube, which cooperates with the fifteenth resistor R15, the eighth resistor R8 and the ninth resistor R9 to set the second current threshold; the second subtraction device can be composed of an operational amplifier and a resistor, and the signal at the first input end of the second subtraction device is subtracted from the signal at the second input end of the second subtraction device to obtain a second difference signal.

[0067] In a transmission line current carrying capacity safety monitoring circuit of the present embodiment, electric energy is connected to the power supply interface and transmitted to the output port, and the first transformer CT1 performs current sampling and outputs a sampling signal. When there is no need to perform current detection or the current of the sampling signal output by the first transformer CT1 is large, the IO1 end of the first controller U1 can output a power-taking signal to control the first thyristor S1 to be turned on, so that the sampling signal is rectified by the first rectifier T1, stored by the energy storage device, and stabilized by the voltage stabilizing device to output the first electric energy. When performing current detection, the sampling signal is converted, amplified and filtered by the signal processing device to output a voltage signal, and the IO4 end of the first controller U1 outputs a first adjustment signal to control the first thyristor S1 to be turned on. The first power tube Q1 is turned on to control the conduction, and the first current carrying threshold is set in cooperation with the eleventh resistor R11, the twelfth resistor R12 and the thirteenth resistor R13. At the same time, the first thermistor RT1 detects the ambient temperature. When the detected temperature is at the minimum temperature threshold set by the third resistor R3 and the fourth resistor R4 and the maximum temperature threshold set by the fifth resistor R5 and the sixth resistor R6, the second comparator A2 and the third comparator A3 both output a high level, the Y end of the first logic chip J1 outputs a first control signal, the second thermistor RT2 detects the temperature of the transmission line, and the first subtraction device calculates the difference between the temperature of the transmission line and the maximum temperature threshold, that is, the first difference signal. The first difference signal controls the first switch tube V1 to turn on, and then The first current carrying threshold is fine-tuned. If the first difference signal is greater than the voltage threshold set by the tenth resistor R10 and the first diode D1 at this time, it indicates that the power transmission line is overheated. If the voltage signal is not greater than the first current carrying threshold at this time, the first comparator A1 outputs a low level, so that the first inverter INV1 outputs a high level, that is, the second potential signal. At this time, the second logic chip J2 cooperates with the second diode D2, the fourth diode D4 and the third diode D3 to self-lock, and the Y end of the fourth logic chip J4 outputs a third potential signal, which is received by the IO6 end of the first controller U1, indicating that overheating occurs at this time. However, due to the excessively high first current carrying threshold, the overload current judgment cannot be performed normally. The IO4 end of the first controller U1 will adjust the first adjustment The duty cycle of the signal reduces the voltage value of the first current-carrying threshold until the voltage signal is greater than the first current-carrying threshold. The first comparator A1 outputs a first potential signal, and the third logic chip J3 outputs a fourth potential signal and is received by the IO7 terminal of the first controller U1. At this time, the IO4 terminal of the first controller U1 will maintain the duty cycle of the first current-carrying threshold at this time so as to serve as a new maximum current-carrying limit. At the same time, the second adjustment signal output by the IO8 terminal of the first controller U1 controls the second power tube Q2 to turn on and cooperate with the fifteenth resistor R15, the eighth resistor R8 and the ninth resistor R9 to set the second current-carrying threshold. The second subtraction device calculates the degree of change of the maximum current-carrying limit, that is, the second difference signal, which is received by the IO9 terminal of the first controller U1.

[0068] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0069] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A transmission line current carrying capacity safety monitoring circuit, characterized in that: The transmission line current carrying capacity safety monitoring circuit comprises: a transmission line module, a current sampling module, a power taking adjustment module, a signal comparison module, a temperature detection module, an intelligent control module, an adjustment processing module, a current carrying threshold module and a change detection module; The transmission line module is used for electric energy transmission; The current sampling module is connected to the power transmission line module, and is used to perform current sampling on the electric energy transmitted by the power transmission line module and output a sampling signal, convert and amplify the sampling signal and filter it, and output a voltage signal; The power taking regulation module is connected to the intelligent control module and the current sampling module, and is used to rectify the sampling signal and store the processed electric energy when receiving the power taking signal output by the intelligent control module, release the stored electric energy and perform voltage stabilization on the released electric energy, and output the first electric energy; The signal comparison module is connected to the current carrying threshold module and the current sampling module, and is used to output a first potential signal when the voltage signal is greater than a first current carrying threshold set by the current carrying threshold module, and output a second potential signal when the voltage signal is less than the first current carrying threshold; The temperature detection module is connected to the power extraction module and is used to set a maximum temperature threshold, a minimum temperature threshold and a voltage threshold, perform temperature detection on the environment and the power transmission line respectively and output a first detection signal and a second detection signal, output a first control signal when the first detection signal is less than the maximum temperature threshold and greater than the minimum temperature threshold, calculate the difference between the second detection signal and the maximum temperature threshold and output the first difference signal, and output a second control signal when the first difference signal is greater than the voltage threshold; The adjustment processing module is connected to the temperature detection module and the signal comparison module, and is used to perform high-level self-locking when receiving the second control signal and the second potential signal, and output a third potential signal when receiving the first control signal, and output a fourth potential signal when outputting the third potential signal and receiving the first potential signal; The intelligent control module is connected to the temperature detection module, the adjustment processing module, the current sampling module and the change detection module, and is used to output a power-taking signal when the current detection is stopped or the voltage signal is greater than the sampling threshold, output a first adjustment signal and a second adjustment signal, and adjust the duty cycle of the first adjustment signal when receiving a third potential signal or outputting a power-taking signal, and maintain the duty cycle of the first adjustment signal when receiving a fourth potential signal, and receive the voltage signal, the first difference signal, the second difference signal output by the change detection module, and the first potential signal; The current carrying threshold module is connected to the intelligent control module, and is used to receive the first electric energy and the first adjustment signal and set the first current carrying threshold, and when receiving the first difference signal, reduce the voltage value of the first current carrying threshold; The change detection module is connected to the current carrying threshold module, and is used to receive a second adjustment signal and set a second current carrying threshold, perform subtraction processing on the second current carrying threshold and the first current carrying threshold, and output a second difference signal.

2. A transmission line current carrying capacity safety monitoring circuit according to claim 1, characterized in that: The power transmission line module includes a power port and an output port; the current sampling module includes a first mutual inductor, a first resistor, a first capacitor and a signal processing device; the intelligent control module includes a first controller; The power port passes through the center of the first transformer and is connected to the output port. The first output end of the first transformer is connected to one end of the first resistor and the first input end of the signal processing device and is connected to the other end of the first resistor, the second input end of the signal processing device, the second output end of the first transformer and the ground through the first capacitor. The output end of the signal processing device is connected to the IO2 end of the first controller and the signal comparison module.

3. A transmission line current carrying capacity safety monitoring circuit according to claim 2, characterized in that: The signal comparison module includes a first comparator and a first inverter; the current threshold module includes an eleventh resistor, a twelfth resistor, a first power tube, a thirteenth resistor, a first switch tube and a fourteenth resistor; The in-phase end of the first comparator is connected to the output end of the signal processing device, the inverting end of the first comparator is connected to the source of the first power tube and is connected to the emitter and the ground end of the first switch tube through the thirteenth resistor, the drain of the first power tube is connected to the power adjustment module and the first end of the twelfth resistor through the eleventh resistor, the second end of the twelfth resistor is connected to the collector of the first switch tube, the gate of the first power tube and the IO4 end of the first controller, the base of the first switch tube is connected to the first end of the fourteenth resistor, the second end of the fourteenth resistor is connected to the temperature detection module, the output end of the first comparator is connected to the IO5 end of the first controller and the input end of the first inverter, and the output end of the first inverter is connected to the adjustment processing module.

4. A transmission line current carrying capacity safety monitoring circuit according to claim 3, characterized in that: The temperature detection module includes a first thermistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a second comparator, a third comparator and a first logic chip; The first end of the first thermistor is connected to one end of the third resistor and the power taking regulation module and is connected to the first end of the sixth resistor through the fifth resistor and the non-inverting end of the second comparator. The other end of the third resistor is connected to the inverting end of the third comparator and one end of the fourth resistor. The other end of the fourth resistor is connected to the second end of the sixth resistor, one end of the second resistor and the ground. The other end of the second resistor is connected to the inverting end of the second comparator, the non-inverting end of the third comparator and the second end of the first thermistor. The output end of the third comparator and the output end of the second comparator are respectively connected to the B end and the A end of the first logic chip. The Y end of the first logic chip is connected to the regulation processing module.

5. A transmission line current carrying capacity safety monitoring circuit according to claim 4, characterized in that: The temperature detection module also includes a second thermistor, a seventh resistor, a first subtraction device, a tenth resistor and a first diode; The first end of the second thermistor is connected to the first end of the first thermistor, the second end of the second thermistor is connected to the first input end of the first subtraction device and is grounded through the seventh resistor, the second input end of the first subtraction device is connected to the first end of the sixth resistor, the output end of the first subtraction device is connected to the second end of the fourteenth resistor and the IO3 end of the first controller and is connected to the cathode of the first diode through the tenth resistor, and the anode of the first diode is connected to the regulation processing module.

6. A transmission line current carrying capacity safety monitoring circuit according to claim 5, characterized in that: The power taking and regulating module includes a first thyristor, a first rectifier, an energy storage device and a voltage stabilizing device; One end of the first thyristor is connected to the first output end of the first mutual inductor, the other end of the first thyristor is connected to the first end of the first rectifier, the second end of the first rectifier is connected to the second output end of the first mutual inductor, the third end of the first rectifier is connected to one end of the energy storage device and the input end of the voltage stabilizing device, the output end of the voltage stabilizing device is connected to the first end of the first thermistor and the first end of the twelfth resistor, and the ground end of the voltage stabilizing device is connected to the other end of the energy storage device, the fourth end of the first rectifier and the ground end.

7. A transmission line current carrying capacity safety monitoring circuit according to claim 5, characterized in that: The adjustment processing module includes a second diode, a third diode, a fourth diode, a second logic chip, a fourth logic chip and a third logic chip; The anode of the second diode is connected to the anode of the first diode, the cathode of the second diode is connected to the B terminal of the second logic chip and the cathode of the third diode, the anode of the third diode is connected to the Y terminal of the second logic chip, the anode of the fourth diode and the A terminal of the fourth logic chip, the A terminal of the second logic chip is connected to the output terminal of the first inverter and the cathode of the fourth diode, the Y terminal of the fourth logic chip is connected to the IO6 terminal of the first controller and the B terminal of the third logic chip, the A terminal of the third logic chip is connected to the input terminal of the first inverter, the Y terminal of the third logic chip is connected to the IO7 terminal of the first controller, and the B terminal of the fourth logic chip is connected to the Y terminal of the first logic chip.

8. A transmission line current carrying capacity safety monitoring circuit according to claim 7, characterized in that: The change detection module includes a fifteenth resistor, an eighth resistor, a ninth resistor, a second power tube, and a second subtraction device; One end of the fifteenth resistor is connected to the output end of the voltage stabilizing device and is connected to the drain of the second power tube through the eighth resistor, the source of the second power tube is connected to the first input end of the second subtraction device and is grounded through the ninth resistor, the output end of the second subtraction device is connected to the IO9 end of the first controller, the gate of the second power tube is connected to the other end of the fifteenth resistor and the IO8 end of the first controller, and the second input end of the second subtraction device is connected to the source of the first power tube.

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