Cable wiring device with electricity taking function

Abstract

The invention provides a cable wiring device with an electricity taking function, which comprises an electricity taking binding post, a transformer, a rectifying and filtering unit, an anti-interference unit and an overvoltage dipolar protection unit, and is characterized in that the electricity taking binding post is provided with a passive capacitor, and electric energy is obtained from a cable through the passive capacitor and a resistance device by utilizing a voltage division principle; a first group of output electrodes of the transformer are used for providing normal power supply output, and a second group of output electrodes are provided with overvoltage protection and resonance suppression circuits; the high-frequency direct-current output pole feedback circuit adjusts the working state of the switching tube according to the difference between the output voltage and a set value so as to control the output voltage. Electric energy is directly obtained from a cable line, stable power supply is provided for underground monitoring equipment, sensors and the like, the stability and reliability of the junction box in a complex electrical environment are effectively improved, and a powerful guarantee is provided for safe production and intelligent management of an underground coal mine.

Description

Technical Field

[0001] The invention relates to the technical field of electrical equipment, and in particular to a cable wiring device with a power-taking function. Background Art

[0002] In complex industrial environments such as underground coal mines that require extremely high safety, explosion-proof high and low voltage junction boxes are core equipment for cable connection and branching. The completeness and reliability of their functions are directly related to the stable operation of the entire electrical system. The design of traditional explosion-proof high and low voltage junction boxes in underground coal mines mainly focuses on the physical connection and branching functions of cables, ensuring accurate transmission and distribution of electrical signals between cables by providing stable terminal blocks and reliable electrical isolation. However, with the widespread application of automation and intelligent equipment in underground coal mines, the functional requirements for junction boxes are far more than simple cable connections.

[0003] Specifically, traditional junction boxes lack the function of power supply, which is particularly prominent in modern coal mining operations. In coal mines, many monitoring equipment, sensors and automation control units require a stable power supply to maintain their normal operation. However, due to the special environment underground, directly laying additional power lines is not only costly, but may also cause safety hazards due to cable damage, short circuits and other problems. Therefore, directly obtaining electricity from existing cable lines has become an ideal solution. Unfortunately, traditional junction boxes do not integrate this function, resulting in the use of additional power supply equipment or complex power supply solutions in actual applications, which not only increases the complexity and cost of the system, but may also affect the stability of the entire electrical system due to mismatch or failure of the power supply equipment.

[0004] In addition, traditional junction boxes are also unable to cope with electrical problems such as overvoltage and interference. In coal mines, due to the large number of equipment and complex electromagnetic environment, abnormal conditions such as overvoltage and surge often occur in cable lines. These abnormal conditions may not only damage the electrical components inside the junction box, but may also spread to other equipment through the cable lines, causing more extensive damage. At the same time, electromagnetic interference may also affect the accurate transmission of electrical signals in the junction box, causing equipment malfunction or data loss. However, traditional junction boxes often lack effective overvoltage protection and anti-interference measures, making it difficult to maintain stable performance in harsh electrical environments. Summary of the invention

[0005] The present invention aims to provide a cable wiring device with a power-taking function, which directly obtains electrical energy from the cable line to provide a stable power supply for underground monitoring equipment, sensors, etc., effectively improving the stability and reliability of the junction box in a complex electrical environment, and providing a strong guarantee for safe production and intelligent management in coal mines.

[0006] The present invention achieves the above object through the following technical solutions:

[0007] A cable wiring device with a power-taking function, comprising:

[0008] A plurality of connectors are provided on the cable wiring device, and each connector is connected to a power-taking control circuit board. The power-taking control circuit board includes:

[0009] A power-taking terminal. The power-taking terminal is configured with a passive capacitor C1. One end of the passive capacitor C1 is directly connected to the power line of the cable, and electrical energy is obtained from the cable by using the voltage division principle through the passive capacitor C1 and a resistive device;

[0010] A transformer T1. The input end of the transformer T1 is connected to the other end of the passive capacitor C1. Among them, the transformer has two sets of output poles. The first set of output poles is used to provide a normal power output. The second set of output poles is configured with an overvoltage protection and resonance suppression circuit, and this circuit includes a rectifier bridge DD1, a capacitor C14, a resistor R14, and a bidirectional diode D1; the input end of the rectifier bridge DD1 is connected to the second set of output poles; the capacitor C14 is connected to the output end of the rectifier bridge DD1; the resistor R14 is connected in series on the signal path between the rectifier bridge DD1 and the bidirectional diode D1 and is used to limit the current or provide a bias voltage; the bidirectional diode is connected to the input end of the transformer T1 to form a feedback loop; when overvoltage appears at the second set of output poles, the bidirectional diode D1 conducts, and the overvoltage energy is fed back to the input end of the transformer T1;

[0011] A rectification and filtering unit. The rectification and filtering unit includes a full-bridge rectification circuit and an inductive filtering circuit, and is used to convert the AC voltage output by the transformer into a stable DC voltage;

[0012] An anti-interference unit, connected to the inductive filtering circuit, and is used to suppress interference signals at the input end;

[0013] An overvoltage diode protection unit, which is used to limit the voltage within a normal range through its reverse breakdown characteristic when the DC output voltage rises abnormally;

[0014] A high-frequency DC output pole feedback circuit, which adjusts the working state of the switching tube according to the difference between the output voltage and the set value, so as to control the output voltage.

[0015] According to a cable wiring device with a power-taking function provided by the present invention, when the cable wiring device is a high-voltage junction box, the power-taking terminal is a high-voltage terminal, and is used to obtain a stable power supply through the voltage division principle by using the passive capacitor C1 and a resistive device in a high-voltage environment; and due to the requirement of the ground current, the charge pump principle is used in the medium and low voltage parts of the circuit. A stable DC output is achieved.

[0016] When the cable wiring device is a low-voltage junction box, the power-taking terminal is a low-voltage terminal, which is used to obtain a stable power supply through the voltage division principle by means of a passive capacitor C1 and a resistor device in a low-voltage environment.

[0017] Alternatively, when the cable wiring device is a low-voltage junction box, the power-taking terminal is a low-voltage terminal, which is used to obtain a stable power supply through the step-down principle of a passive transformer in a low-voltage environment.

[0018] According to a cable wiring device with a power-taking function provided by the present invention, a protection unit is further provided at the input end of the transformer T1. The protection unit includes an overvoltage protection element and a fast fuse. One end of the overvoltage protection element is connected to the first input end of the transformer T1, and the other end of the overvoltage protection element is connected to the second input end of the transformer T1 and a bidirectional diode D1. One end of the fast fuse is connected to the bidirectional diode D1 and a capacitor C14, and the other end of the fast fuse is grounded.

[0019] According to a cable wiring device with a power-taking function provided by the present invention, the anti-interference unit includes a capacitor CY1, a capacitor CY2, and a capacitor CY3. One end of the capacitor CY1 and the capacitor CY2 are respectively connected to the inductive filter circuit, and the other ends of the capacitor CY1 and the capacitor CY2 are both grounded. The capacitor CY3 is connected between the common connection point of the capacitor CY1 and the capacitor CY2 and the ground.

[0020] According to a cable wiring device with a power-taking function provided by the present invention, the overvoltage diode protection unit includes:

[0021] An overvoltage protection module, including a plurality of transient voltage suppression diodes or zener diodes. When the output voltage exceeds a preset threshold, the transient voltage suppression diode or the zener diode conducts, discharging the overvoltage energy to a safe path;

[0022] An output regulation module, including a switching transistor Q1, an output inductor L1, and a plurality of output capacitors. The switching transistor Q1 adjusts the output voltage by controlling its gate voltage. The inductor L1 and the plurality of output capacitors form an LC filter for smoothing the output voltage and current;

[0023] A comparator module, including a comparator U1. The output end of the comparator U1 is connected to the gate of the switching transistor Q1. The non-inverting input end of the comparator U1 is connected to the anti-interference unit, and the inverting input end of the comparator U1 is connected with resistors R5, R7, and a capacitor C3.

[0024] According to a cable wiring device with a power-taking function provided by the present invention, the high-frequency DC output pole feedback circuit includes:

[0025] A feedback controller U2, which is used to receive a feedback signal and control the on and off of a switching transistor Q2 to regulate the output voltage;

[0026] A high-frequency power transformer T2, the primary winding of the high-frequency power transformer T2 is respectively connected to the switching transistor Q2 and the feedback controller U2, and one secondary winding of the high-frequency power transformer T2 is used to output a +12V voltage;

[0027] The switching transistor Q2 conducts and turns off according to the control signal of the feedback controller U2, thereby regulating the output voltage of the transformer T2;

[0028] An optocoupler TF1, the input end of the optocoupler TF1 is connected to another secondary winding of the high-frequency power transformer T2, which is used to isolate and transmit the feedback signal, and feeds back the change of the output voltage to the feedback controller U2 through the output end;

[0029] A resistor regulator RW11, which is connected to the primary winding of the high-frequency power transformer T2 and the feedback controller U2, and is used to adjust the intensity of the feedback signal.

[0030] According to a cable wiring device with a power-taking function provided by the present invention, when the high-frequency DC output pole feedback circuit receives the voltage output by the output regulation module of the overvoltage diode protection unit, the voltage is transformed by the transformer T2, and is rectified and smoothed through a rectifying diode and a filtering capacitor;

[0031] The feedback controller U2 monitors the output voltage in real time, compares it with a preset set value, and dynamically adjusts the working state of the switching transistor Q2 according to the comparison result, including the conduction time and conduction frequency of the switching transistor;

[0032] The output protection circuit monitors the output voltage in real time. When a reverse current or abnormal output voltage is detected, protection measures are taken quickly to prevent the reverse current or abnormal voltage from damaging the circuit;

[0033] Among them, the starting voltage is adjusted through the resistor regulator RW11 to meet the specific voltage requirements of different loads.

[0034] According to a cable wiring device with a power-taking function provided by the present invention, it further includes the following steps for realizing output voltage control through the feedback controller U2:

[0035] The feedback controller U2 monitors the output voltage Vout in real time, compares it with a preset set value Vset, and dynamically adjusts the working state of the switching transistor Q2 according to the comparison result, including the conduction time ton and conduction frequency fsw of the switching transistor. The specific implementation principle is as follows:

[0036] The feedback controller U2 monitors the output voltage Vout in real time through the built-in analog-to-digital converter and converts it into a digital signal; compares the monitored Vout with the preset set value Vset to obtain the voltage error signal e = Vset - Vout; the feedback controller U2 adopts a proportional-integral-derivative control algorithm and calculates the control signal u according to the voltage error signal e; where the control signal u is associated with the on-time ton and on-frequency fsw of the switching transistor Q2; according to the control signal u, the feedback controller U2 dynamically adjusts the on-time ton of the switching transistor Q2, that is, the time length during which the switching transistor Q2 conducts within a switching period; at the same time, the feedback controller U2 may also adjust the on-frequency fsw of the switching transistor Q2 according to the control signal u, that is, the number of times the switching transistor Q2 conducts and turns off per unit time; where the adjustment of the on-time ton and on-frequency fsw follows the following principle: when Vout < Vset, increase ton or fsw to increase the output voltage; when Vout > Vset, decrease ton or fsw to decrease the output voltage.

[0037] A cable wiring device with a power-taking function provided by the present invention further includes:

[0038] A resonant inductor, the resonant inductor is connected in series or in parallel with the passive capacitor C1 to form a resonant circuit, and the controller adjusts the inductance value of the resonant inductor or the capacitance value of the passive capacitor C1 according to the voltage frequency f on the cable, so that the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable;

[0039] When the resonant inductor is connected in series or in parallel with the passive capacitor C1, the resonant frequency f0 is expressed by the following formula:

[0040]

[0041] Where L is the inductance value of the resonant inductor and C is the capacitance value of the passive capacitor C1.

[0042] A cable wiring device with a power-taking function provided by the present invention monitors the voltage frequency f on the cable in real time through the controller and calculates the required resonant frequency f0; according to the calculated resonant frequency f0, the controller dynamically adjusts the inductance value of the resonant inductor or the capacitance value of the passive capacitor C1, so that the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable; when the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable, the resonant circuit presents a pure resistive state, at this time the energy exchange between the passive capacitor C1 and the resonant inductor reaches the maximum, and the electric energy obtained from the cable also reaches the maximum; due to the constant frequency, a stable DC12V power supply is finally obtained.

[0043] It can be seen that, compared with the existing explosion-proof junction boxes, the present invention proposes a cable wiring device with a power-taking function. This device not only retains the cable connection and branching functions of traditional junction boxes, but also innovatively integrates a power-taking control circuit board, which directly obtains electrical energy from the cable line through the principle of passive capacitance voltage division to provide a stable power supply for underground monitoring equipment, sensors, etc. At the same time, the device is also equipped with functional modules such as overvoltage protection and resonance suppression circuits, rectification and filtering units, anti-interference units, and high-frequency DC output pole feedback circuits, effectively improving the stability and reliability of the junction box in complex electrical environments and providing a strong guarantee for the safe production and intelligent management in coal mines.

[0044] Furthermore, the device is equipped with an overvoltage protection and resonance suppression circuit. When overvoltage or resonance occurs in the cable line, this circuit can respond quickly, feedback the overvoltage energy to the input end of the transformer or perform resonance suppression to protect the subsequent circuits from damage, effectively improving the stability and safety of the wiring device in harsh electrical environments and reducing equipment failures and safety accidents caused by overvoltage or resonance.

[0045] Furthermore, the high-frequency DC output pole feedback circuit in the device can dynamically adjust the working state of the switching tube according to the difference between the output voltage and the set value, thereby precisely controlling the output voltage. This not only improves the energy utilization efficiency but also ensures the stability of the output voltage, providing a reliable power supply guarantee for underground equipment.

[0046] Furthermore, the present invention adjusts the resonance frequency of capacitor C1 and the subsequent circuit to match the voltage frequency on the high-voltage cable, thereby improving the power-taking efficiency.

[0047] The following further elaborates on the present invention in conjunction with the accompanying drawings and specific embodiments. Description of the Drawings

[0048] Figure 1 It is the circuit schematic diagram of the power-taking terminal, transformer, and overvoltage protection and resonance suppression circuit in an embodiment of a cable wiring device with a power-taking function according to the present invention.

[0049] Figure 2 It is the circuit schematic diagram of the anti-interference unit and overvoltage diode protection unit in an embodiment of a cable wiring device with a power-taking function according to the present invention.

[0050] Figure 3 It is the circuit schematic diagram of the high-frequency DC output pole feedback circuit in an embodiment of a cable wiring device with a power-taking function according to the present invention. Detailed Description of the Embodiment

[0051] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0052] As used herein, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0053] See Figures 1 to 3 , this embodiment provides a cable wiring device with a power-taking function, including:

[0054] The cable wiring device is provided with a plurality of connectors, and each connector is connected to a power-taking control circuit board. The power-taking control circuit board includes:

[0055] A power-taking terminal, the power-taking terminal is configured with a passive capacitor C1. One end of the passive capacitor C1 is directly connected to the power line of the cable, and electrical energy is obtained from the cable by using the voltage division principle through the passive capacitor C1 and a resistive device.

[0056] A transformer T1, the input end of the transformer T1 is connected to the other end of the passive capacitor C1; wherein, the transformer has two sets of output poles. The first set of output poles is used to provide a normal power output, and the second set of output poles is configured with an overvoltage protection and resonance suppression circuit, which includes a rectifier bridge DD1, a capacitor C14, a resistor R14, and a bidirectional diode D1; the input end of the rectifier bridge DD1 is connected to the second set of output poles; the capacitor C14 is connected to the output end of the rectifier bridge DD1; the resistor R14 is connected in series on the signal path between the rectifier bridge DD1 and the bidirectional diode D1 to limit the current or provide a bias voltage; the bidirectional diode is connected to the input end of the transformer T1 to form a feedback loop; when overvoltage appears at the second set of output poles, the bidirectional diode D1 conducts, and the overvoltage energy is fed back to the input end of the transformer T1, thereby preventing the overvoltage from damaging the transformer T1 and suppressing the circuit resonance to avoid the capacitor C14 from being broken down due to resonance.

[0057] A rectification and filtering unit, the rectification and filtering unit includes a full-bridge rectification circuit and an inductive filtering circuit, such as BD1 and DL1, for converting the AC voltage output by the transformer into a stable DC voltage.

[0058] An anti-interference unit, connected to the inductive filter circuit, is used to suppress the interference signals at the input end.

[0059] An overvoltage diode protection unit is used to limit the voltage within the normal range through its reverse breakdown characteristic when the DC output voltage abnormally rises.

[0060] A high-frequency DC output pole feedback circuit adjusts the working state of the switching tube according to the difference between the output voltage and the set value, thereby controlling the output voltage.

[0061] When the cable wiring device is a high-voltage junction box, the power-taking terminal is a high-voltage terminal, which is used to obtain a stable power supply through the voltage division principle by using the passive capacitor C1 and resistive devices in a high-voltage environment; and due to the requirement of the ground current, the charge pump principle is used in the medium and low-voltage parts of the circuit to achieve stable DC output.

[0062] When the cable wiring device is a low-voltage junction box, the power-taking terminal is a low-voltage terminal, which is used to obtain a stable power supply through the voltage division principle by using the passive capacitor C1 and resistive devices in a low-voltage environment.

[0063] Or, when the cable wiring device is a low-voltage junction box, the power-taking terminal is a low-voltage terminal, which is used to obtain a stable power supply through the step-down principle of a passive transformer in a low-voltage environment.

[0064] In this embodiment, a protection unit is further provided at the input end of the transformer T1. The protection unit includes an overvoltage protection element and a fast fuse. One end of the overvoltage protection element is connected to the first input end of the transformer T1, the other end of the overvoltage protection element is connected to the second input end of the transformer T1 and the bidirectional diode D1, one end of the fast fuse is connected to the bidirectional diode D1 and the capacitor C14, and the other end of the fast fuse is grounded.

[0065] In this embodiment, as Figure 2 shown, the anti-interference unit includes capacitors CY1, CY2, and CY3. One ends of the capacitors CY1 and CY2 are respectively connected to the inductive filter circuit, and the other ends of the capacitors CY1 and CY2 are both grounded, which are used to filter out high-frequency noise. The capacitor CY3 is connected between the common connection point of the capacitors CY1 and CY2 and the ground, which is used to further smooth the signal and reduce low-frequency noise and ripple.

[0066] In this embodiment, the overvoltage diode protection unit includes:

[0067] An overvoltage protection module includes a plurality of transient voltage suppression diodes or zener diodes. When the output voltage exceeds the preset threshold, the transient voltage suppression diodes or zener diodes conduct, and discharge the overvoltage energy to a safe path.

[0068] The output regulation module includes a switching transistor Q1, an output inductor L1, and multiple output capacitors. The switching transistor Q1 adjusts the output voltage by controlling its gate voltage. The inductor L1 and the multiple output capacitors form an LC filter for smoothing the output voltage and current.

[0069] The comparator module includes a comparator U1. The output terminal of the comparator U1 is connected to the gate of the switching transistor Q1. The non-inverting input terminal of the comparator U1 is connected to the anti-interference unit, and the inverting input terminal of the comparator U1 is connected with resistors R5, R7, and a capacitor C3.

[0070] In this embodiment, as Figure 3 shown, the high-frequency DC output pole feedback circuit includes:

[0071] A feedback controller U2 for receiving a feedback signal and controlling the conduction and cutoff of the switching transistor Q2 to regulate the output voltage;

[0072] A high-frequency power transformer T2. The primary winding of the high-frequency power transformer T2 is respectively connected to the switching transistor Q2 and the feedback controller U2. One secondary winding of the high-frequency power transformer T2 is used to output a +12V voltage;

[0073] A switching transistor Q2 that conducts and cuts off according to the control signal of the feedback controller U2, thereby regulating the output voltage of the transformer T2;

[0074] An optocoupler TF1. The input terminal of the optocoupler TF1 is connected to another secondary winding of the high-frequency power transformer T2, which is used for isolating and transmitting the feedback signal and feeding back the change of the output voltage to the feedback controller U2 through the output terminal;

[0075] A resistor regulator RW11 is connected to the primary winding of the high-frequency power transformer T2 and the feedback controller U2, and is used for adjusting the intensity of the feedback signal to precisely control the stability of the output voltage.

[0076] Among them, the high-frequency DC output pole feedback circuit realizes the precise regulation and stable control of the +12V output voltage through the coordinated operation of each component, improving the output accuracy and reliability of the power supply device.

[0077] Another secondary winding of the high-frequency power transformer T2 is used to output a feedback signal related to the +12V voltage; an optocoupler TF1, whose input terminal is connected to another secondary winding of the high-frequency power transformer T2, is used for receiving the feedback signal and isolating and transmitting it to the output terminal.

[0078] When the high-frequency DC output pole feedback circuit receives the voltage output by the output regulation module of the overvoltage diode protection unit, the voltage is transformed by the transformer T2 and rectified and smoothed through a rectifier diode and a filter capacitor;

[0079] The feedback controller U2 monitors the output voltage in real time, compares it with a preset set value, and dynamically adjusts the working state of the switching transistor Q2 according to the comparison result, including the conduction time and conduction frequency of the switching transistor, so as to accurately control the output voltage to reach the set value;

[0080] The output protection circuit monitors the output voltage in real time. When a reverse current or abnormal output voltage is detected, it quickly takes protective measures, such as cutting off the circuit or limiting the current, to prevent the reverse current or abnormal voltage from damaging the circuit.

[0081] Among them, the starting voltage is adjusted by the resistance regulator RW11 to meet the specific voltage requirements of different loads and improve the adaptability and flexibility of the circuit.

[0082] In this embodiment, the following steps for controlling the output voltage through the feedback controller U2 are also included:

[0083] The feedback controller U2 monitors the output voltage Vout in real time, compares it with a preset set value Vset, and dynamically adjusts the working state of the switching transistor Q2 according to the comparison result, including the conduction time ton and conduction frequency fsw of the switching transistor. The specific implementation principle is as follows:

[0084] The feedback controller U2 monitors the output voltage Vout in real time through a built-in analog-to-digital converter and converts it into a digital signal; compares the monitored Vout with a preset set value Vset to obtain a voltage error signal e = Vset - Vout; the feedback controller U2 adopts a proportional-integral-derivative control algorithm and calculates a control signal u according to the voltage error signal e; among them, the control signal u is associated with the conduction time ton and conduction frequency fsw of the switching transistor Q2, and the specific relationship is determined by the internal algorithm and circuit parameters of the controller; according to the control signal

[0085] u, the feedback controller U2 dynamically adjusts the conduction time ton of the switching transistor Q2, that is, within one switching cycle,

[0086] the length of time the switching transistor Q2 is conducting; at the same time, the feedback controller U2 may also adjust the conduction frequency fsw of the switching transistor Q2 according to the control signal u, that is, the number of times the switching transistor Q2 conducts and turns off per unit time; among them,

[0087] The adjustment of the conduction time ton and conduction frequency fsw follows the following principle: when Vout < Vset, increase ton

[0088] or fsw to increase the output voltage; when Vout > Vset, decrease ton or fsw to reduce the output voltage.

[0089] ·Through the above dynamic adjustment process, the controller U2 makes the output voltage Vout gradually approach and stabilize near the preset set value Vset, achieving precise control of the output voltage.

[0090] In this embodiment, it further includes:

[0091] A resonant inductor, which is connected in series or parallel with the passive capacitor C1 to form a resonant circuit. The controller adjusts the inductance value of the resonant inductor or the capacitance value of the passive capacitor C1 according to the voltage frequency f on the cable, so that the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable;

[0092] When the resonant inductor is connected in series or parallel with the passive capacitor C1, the resonant frequency f0 is expressed by the following formula:

[0093]

[0094] where L is the inductance value of the resonant inductor and C is the capacitance value of the passive capacitor C1.

[0095] In this embodiment, the controller monitors the voltage frequency f on the cable in real time and calculates the required resonant frequency f0; according to the calculated resonant frequency f0, the controller dynamically adjusts the inductance value of the resonant inductor or the capacitance value of the passive capacitor C1, so that the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable; when the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable, the resonant circuit presents a pure resistive state. At this time, the energy exchange between the passive capacitor C1 and the resonant inductor reaches the maximum, and the electric energy obtained from the cable also reaches the maximum; due to the constant frequency, a stable DC12V power supply is finally obtained. Among them, the adjustment methods include but are not limited to: adjusting the inductance value by changing the number of turns of the inductor, the magnetic core material or the air gap size, or adjusting the capacitance value by switching capacitors C1 with different capacitance values.

[0096] In summary, compared with the existing explosion-proof junction box, this embodiment proposes a cable wiring device with a power-taking function. This device not only retains the cable connection and branching functions of the traditional junction box, but also innovatively integrates a power-taking control circuit board, directly obtains electric energy from the cable line through the passive capacitor voltage division principle, and provides a stable power supply for underground monitoring equipment, sensors, etc. At the same time, the device is also equipped with function modules such as overvoltage protection and resonance suppression circuits, rectification and filtering units, anti-interference units, and high-frequency DC output pole feedback circuits, effectively improving the stability and reliability of the junction box in a complex electrical environment, and providing a strong guarantee for the safety production and intelligent management in coal mines.

[0097] Furthermore, the device is equipped with an overvoltage protection and resonance suppression circuit. When overvoltage or resonance occurs in the cable line, this circuit can respond quickly, feedback the overvoltage energy to the input end of the transformer or suppress resonance, protecting the subsequent circuit from damage, effectively improving the stability and safety of the wiring device in a harsh electrical environment, and reducing equipment failures and safety accidents caused by overvoltage or resonance.

[0098] Furthermore, the high-frequency DC output pole feedback circuit in the device can dynamically adjust the working state of the switching tube according to the difference between the output voltage and the set value, thereby precisely controlling the output voltage. This not only improves the energy utilization efficiency but also ensures the stability of the output voltage, providing a reliable power supply guarantee for downhole equipment.

[0099] Furthermore, the present invention improves the power extraction efficiency by adjusting the resonance frequency of capacitor C1 and the subsequent circuit to match the voltage frequency on the high-voltage cable.

[0100] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0101] The above embodiments are only the preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantive changes and substitutions made by those skilled in the art based on the present invention belong to the scope required to be protected by the present invention.

Claims

1. A cable connection device with a power supply function, characterized in that: The cable connection device is provided with a plurality of connectors, each of which is connected to a power taking control circuit board, and the power taking control circuit board includes: The power-taking terminal is equipped with a passive capacitor C1. One end of the passive capacitor C1 is directly connected to the power line of the cable, and the other end of the passive capacitor C1 is connected to the input end of the transformer. The other input end of the transformer is directly connected to the ground. The varistor device protects the transformer input. This principle ensures that stable power can be obtained from the cable under simple and compact conditions. A transformer T1, wherein the input end of the transformer T1 is connected to the other end of the passive capacitor C1; wherein the transformer has two groups of output poles, the first group of output poles is used to provide normal power output, and the second group of output poles is configured with an overvoltage protection and resonance suppression circuit, the circuit comprising a rectifier bridge DD1, a capacitor C14, a resistor R14 and a bidirectional diode D1; the input end of the rectifier bridge DD1 is connected to the second group of output poles; the capacitor C14 is connected to the output end of the rectifier bridge DD1; the resistor R14 is connected in series on the signal path between the rectifier bridge DD1 and the bidirectional diode D1, for limiting current or providing bias voltage; the bidirectional diode is connected to the input end of the transformer T1 to form a feedback loop; when the second group of output poles has an overvoltage, the bidirectional diode D1 is turned on to feed back the overvoltage energy to the input end of the transformer T1; A rectifier and filter unit, the rectifier and filter unit comprising a full-bridge rectifier circuit and an inductor filter circuit, for converting the AC voltage output by the transformer into a stable DC voltage; An anti-interference unit, connected to the inductor filter circuit, for suppressing interference signals at the input end; The overvoltage diode protection unit is used to limit the voltage within the normal range through its reverse breakdown characteristics when the DC output voltage rises abnormally; The high-frequency DC output feedback circuit adjusts the working state of the switch tube according to the difference between the output voltage and the set value, thereby controlling the output voltage.

2. The device according to claim 1, characterized in that: When the cable connection device is a high-voltage connection box, the power connection post is a high-voltage connection post, which is used to obtain a stable power supply through the voltage division principle of the passive capacitor C1 and the transformer under a high-voltage environment; When the cable connection device is a low-voltage connection box, the power connection post is a low-voltage connection post, which is used to obtain a stable power supply by using a voltage division principle through a passive capacitor C1 and a resistor device in a low-voltage environment.

3. The device according to claim 1, characterized in that: A protection unit is also provided at the input end of the transformer T1, and the protection unit includes an overvoltage protection element and a fast fuse. One end of the overvoltage protection element is connected to the first input end of the transformer T1, and the other end of the overvoltage protection element is connected to the second input end of the transformer T1 and the bidirectional diode D1. One end of the fast fuse is connected to the bidirectional diode D1 and the capacitor C14, and the other end of the fast fuse is grounded.

4. The device according to claim 1, characterized in that: The anti-interference unit includes capacitor CY1, capacitor CY2 and capacitor CY3, one end of the capacitor CY1 and capacitor CY2 are respectively connected to the inductor filter circuit, the other ends of the capacitor CY1 and capacitor CY2 are grounded, and the capacitor CY3 is connected between the common connection point of the capacitor CY1 and capacitor CY2 and the ground.

5. The device according to claim 1, characterized in that: The overvoltage diode protection unit comprises: An overvoltage protection module, including a plurality of transient voltage suppression diodes or voltage regulator diodes. When the output voltage exceeds a preset threshold, the transient voltage suppression diodes or voltage regulator diodes are turned on to discharge the overvoltage energy to a safe path; An output regulation module, comprising a switch tube Q1, an output inductor L1 and a plurality of output capacitors, wherein the switch tube Q1 regulates the output voltage by controlling its gate voltage, and the inductor L1 and the plurality of output capacitors constitute an LC filter for smoothing the output voltage and current; The comparator module includes a comparator U1, wherein the output end of the comparator U1 is connected to the gate of the switch tube Q1, the non-inverting input end of the comparator U1 is connected to the anti-interference unit, and the inverting input end of the comparator U1 is connected to resistors R5, R7 and a capacitor C3.

6. The device according to claim 5, characterized in that: The high-frequency DC output feedback circuit comprises: The feedback controller U2 is used to receive the feedback signal and control the on and off of the switch tube Q2 to adjust the output voltage; A high-frequency power transformer T2, wherein the primary winding of the high-frequency power transformer T2 is respectively connected to the switch tube Q2 and the feedback controller U2, and a secondary winding of the high-frequency power transformer T2 is used to output a +12V voltage; The switch tube Q2 is turned on and off according to the control signal of the feedback controller U2, thereby adjusting the output voltage of the transformer T2; Optocoupler TF1, the input end of the optocoupler TF1 is connected to another secondary winding of the high-frequency power transformer T2, for isolating and transmitting feedback signals, and feeding back the output voltage change to the feedback controller U2 through the output end; The resistance regulator RW11 is connected to the primary winding of the high-frequency power transformer T2 and the feedback controller U2, and is used to adjust the strength of the feedback signal.

7. The device according to claim 6, characterized in that: When the high-frequency DC output feedback circuit receives the voltage output by the output adjustment module of the overvoltage diode protection unit, the voltage is transformed by transformer T2, and rectified and smoothed by the rectifier diode and filter capacitor; The feedback controller U2 monitors the output voltage in real time and compares it with the preset set value, and dynamically adjusts the working state of the switch tube Q2 according to the comparison result, including the on-time and on-frequency of the switch tube; The output protection circuit monitors the output voltage in real time. When reverse current or abnormal output voltage is detected, protection measures are taken immediately to prevent reverse current or abnormal voltage from damaging the circuit. The starting voltage is adjusted by the resistor adjuster RW11 to meet the specific voltage requirements of different loads.

8. The device according to claim 7, characterized in that It further includes the following steps to implement output voltage control through the feedback controller U2: The feedback controller U2 monitors the output voltage Vout in real time, compares it with the preset set value Vset, and dynamically adjusts the working state of the switching transistor Q2 according to the comparison result, including the on-time ton and the switching frequency fsw of the switching transistor. The specific implementation principle is as follows: The feedback controller U2 monitors the output voltage Vout in real time through the built-in analog-to-digital converter and converts it into a digital signal; compares the monitored Vout with the preset set value Vset to obtain the voltage error signal e = Vset - Vout; the feedback controller U2 adopts a proportional-integral-derivative control algorithm and calculates the control signal u according to the voltage error signal e; where the control signal u is associated with the on-time ton and the switching frequency fsw of the switching transistor Q2; according to the control signal u, the feedback controller U2 dynamically adjusts the on-time ton of the switching transistor Q2, that is, the time length during which the switching transistor Q2 conducts within a switching period; at the same time, the feedback controller U2 may also adjust the switching frequency fsw of the switching transistor Q2 according to the control signal u, that is, the number of times the switching transistor Q2 conducts and turns off per unit time; among them, the adjustment of the on-time ton and the switching frequency fsw follows the following principle: when Vout < Vset, increase ton or fsw to increase the output voltage; when Vout > Vset, decrease ton or fsw to decrease the output voltage.

9. The device according to any one of claims 1 to 8, characterized in that It further includes: A resonant inductor, the resonant inductor is connected in series or parallel with the passive capacitor C1 to form a resonant circuit, and the controller adjusts the inductance value of the resonant inductor or the capacitance value of the passive capacitor C1 according to the voltage frequency f on the cable, so that the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable; When the resonant inductor is connected in series or parallel with the passive capacitor C1, the resonant frequency f0 is expressed as the following formula: where, L is the inductance value of the resonant inductor, and C is the capacitance value of the passive capacitor C1.

10. The device according to claim 9, wherein: The controller monitors the voltage frequency f on the cable in real time and calculates the required resonant frequency f0; according to the calculated resonant frequency f0, the controller dynamically adjusts the inductance value of the resonant inductor or the capacitance value of the passive capacitor C1, so that the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable; when the resonant frequency f0 of the resonant circuit matches the voltage frequency f on the cable, the resonant circuit presents a pure resistive state, at this time the energy exchange between the passive capacitor C1 and the resonant inductor reaches the maximum, and the electric energy obtained from the cable also reaches the maximum; due to the constant frequency, a stable DC12V power supply is finally obtained.

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