Cable insulation detection system

Abstract

The utility model provides a cable insulation detection system, and belongs to the technical field of insulation detection. The cable insulation detection system comprises a high voltage generation module, a reference resistor, a comparison module, a central control module and an alarm module. The output end of the high-voltage generation module is used for connecting one end of a to-be-tested cable. The first input end of the comparison module is used for connecting the other end of the to-be-tested cable. The output end of the high-voltage generation module is connected with the first end of the reference resistor; the second end of the reference resistor is connected with the second input end of the comparison module; the high-voltage generation module is used for outputting high-voltage signals; the output end of the comparison module is connected with the central control module which is connected with the alarm module. The problem that a traditional cable insulation detection mode is poor in accuracy can be solved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of insulation detection, and particularly to a cable insulation detection system. Background Art

[0002] With the rapid development of industries such as electric power and communication, as a key transmission medium, the insulation performance of cables is directly related to the safe and stable operation of the system. However, in practical applications, cables often suffer from insulation performance degradation due to factors such as aging and environmental erosion, which may further lead to serious accidents such as short circuits and electric leakage, posing a major threat to production safety and personal safety.

[0003] Traditional cable insulation detection methods mostly rely on manual regular inspections, which are not only inefficient but also difficult to comprehensively cover all cables, easily missing potential safety hazards. In addition, the detection process is easily affected by environmental interference, affecting the accuracy of the results. Utility Model Content

[0004] Embodiments of the present disclosure provide a cable insulation detection system to solve the problem of poor accuracy in traditional cable insulation detection methods.

[0005] Embodiments of the present disclosure provide a cable insulation detection system, including a high-voltage generation module, a reference resistor, a comparison module, a central control module, and an alarm module;

[0006] The output end of the high-voltage generation module is used to connect one end of the cable to be tested, and the first input end of the comparison module is used to connect the other end of the cable to be tested;

[0007] The output end of the high-voltage generation module is connected to the first end of the reference resistor, and the second end of the reference resistor is connected to the second input end of the comparison module;

[0008] The high-voltage generation module is used to output a high-voltage signal;

[0009] The output end of the comparison module is connected to the central control module, and the central control module is connected to the alarm module.

[0010] In an exemplary embodiment of the present disclosure, the high-voltage generation module includes a pulse generation circuit, a drive circuit, a boost circuit, and a feedback circuit;

[0011] The output end of the pulse generation circuit is connected to the input end of the drive circuit, the output end of the drive circuit is connected to the output end of the boost circuit, the output end of the boost circuit is connected to the input end of the feedback circuit, and the output end of the feedback circuit is connected to the feedback end of the pulse generation circuit;

[0012] The output end of the boost circuit is used to output a high-voltage signal.

[0013] In an exemplary embodiment of the present disclosure, the pulse generating circuit includes a pulse generator U1 and a resistor R3;

[0014] The power supply terminal of the pulse generator U1 is used to connect to the VCC power supply. The non-inverting input terminal of the pulse generator U1 is connected to the feedback terminal of the pulse generator U1 through the resistor R3. The inverting input terminal of the pulse generator U1 is used to connect to a reference voltage. The output terminal of the pulse generator U1 is connected to the input terminal of the driving circuit.

[0015] In an exemplary embodiment of the present disclosure, the driving circuit includes a resistor R1, a diode D1, a switching transistor Q1, and a switching transistor Q2;

[0016] The output terminal of the resistor R1 is connected to the output terminal of the pulse generator U1. The second terminal of the resistor R1 is connected to the anode of the diode D1. The cathode of the diode D1 is connected to the control terminal of the switching transistor Q2. The anode of the diode D1 is connected to the control terminal of the switching transistor Q1. The first terminal of the switching transistor Q1 is connected to the control terminal of the switching transistor Q2. The second terminal of the switching transistor Q1 is grounded. The first terminal of the switching transistor Q2 is connected to the input terminal of the boost circuit. The second terminal of the switching transistor Q2 is grounded.

[0017] In an exemplary embodiment of the present disclosure, the boost circuit includes a transformer T1, a diode D2, and a capacitor C4;

[0018] The first input terminal of the transformer T1 is used to connect to the VCC power supply. The second input terminal of the transformer T1 is connected to the first terminal of the switching transistor Q2. The first output terminal of the transformer T1 is connected to the anode of the diode D2. The second output terminal of the transformer T1 is grounded. The cathode of the diode D2 is grounded through the capacitor C4. The cathode of the diode D2 is used to output a high-voltage signal.

[0019] In an exemplary embodiment of the present disclosure, the feedback circuit includes a resistor R7, a resistor R8, a resistor R9, and a variable resistor RP1;

[0020] The first terminal of the resistor R7 is connected to the cathode of the diode D2. The second terminal of the resistor R7 is grounded through the resistor R8. The second terminal of the resistor R7 is connected to the first terminal of the variable resistor RP1 through the resistor R9. The first terminal of the variable resistor RP1 is connected to the inverting input terminal of the pulse generator U1. The sliding terminal of the variable resistor RP1 is connected to the compensation terminal of the pulse generator U1. The second terminal of the variable resistor RP1 is grounded.

[0021] In an exemplary embodiment of the present disclosure, the reference resistor includes a resistor RL; the comparison module includes a resistor R10 and an operational amplifier U2;

[0022] The inverting input terminal of the operational amplifier U2 serves as the first input terminal of the comparison module. The first end of the resistor RL is connected to the output terminal of the high-voltage generating module, the second end of the resistor RL is connected to the non-inverting input terminal of the operational amplifier U2, the non-inverting input terminal of the operational amplifier U2 is grounded through the resistor R10, and the output terminal of the operational amplifier U2 is connected to the central control module.

[0023] In an exemplary embodiment of the present disclosure, the comparison module further includes a resistor R11, an optocoupler U3, a triode Q3, and a resistor R13;

[0024] The first end of the resistor R11 is connected to the output terminal of the operational amplifier U2, the second end of the resistor R11 is connected to the first input terminal of the optocoupler U3, the second output terminal of the optocoupler U3 is grounded, the first output terminal of the optocoupler U3 is used to connect to the VDD power supply, the second output terminal of the optocoupler U3 is connected to the base of the triode Q3, the collector of the triode Q3 is used to connect to the VDD power supply, the emitter of the triode Q3 is grounded through the resistor R13, and the emitter of the triode Q3 is connected to the central control module.

[0025] The beneficial effects of the cable insulation detection system provided by the embodiments of the present disclosure are as follows:

[0026] The embodiments of the present disclosure can automatically apply a high-voltage signal, use a reference resistor to provide a stable voltage reference, accurately compare the voltage differences between the cable under test and the reference resistor through the comparison module, and quickly evaluate the cable insulation condition. Once it is found that the insulation performance does not meet the standard, the central control module immediately triggers an alarm, effectively preventing potential safety hazards. This design not only improves the detection efficiency and accuracy, but also greatly enhances the safety and reliability of cable use, providing strong technical support for cable maintenance and management in the fields of electric power, communication, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 It is a structural block diagram of the cable insulation detection system provided by the embodiments of the present disclosure;

[0029] Figure 2 It is a structural block diagram of the high-voltage generating module provided by the embodiments of the present disclosure;

[0030] Figure 3It is the circuit diagram of the cable insulation detection system provided by the embodiments of the present disclosure. Detailed implementation manners

[0031] In order to enable those skilled in the art to better understand this solution, the technical solutions in the embodiments of this solution will be clearly described below in conjunction with the accompanying drawings in the embodiments of this solution. Obviously, the described embodiments are part of the embodiments of this solution, rather than all the embodiments. Based on the embodiments in this solution, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of this solution.

[0032] The term "including" in the specification, claims and above-mentioned accompanying drawings of this solution, as well as any other variations, means "including but not limited to", and is intended to cover non-exclusive inclusion, not limited to the examples listed in the text. In addition, terms such as "first" and "second" are used to distinguish different objects, rather than to describe a specific order.

[0033] The implementation of the present disclosure will be described in detail below in conjunction with specific accompanying drawings:

[0034] Figure 1 It is the structural schematic diagram of a cable insulation detection system provided by the embodiments of the present disclosure. Refer to Figure 1 , the cable insulation detection system includes a high-voltage generation module, a reference resistor, a comparison module, a central control module and an alarm module; the output end of the high-voltage generation module is used to connect one end of the cable to be tested, and the first input end of the comparison module is used to connect the other end of the cable to be tested; the output end of the high-voltage generation module is connected to the first end of the reference resistor, and the second end of the reference resistor is connected to the second input end of the comparison module; the high-voltage generation module is used to output a high-voltage signal; the output end of the comparison module is connected to the central control module, and the central control module is connected to the alarm module.

[0035] In this embodiment, the high-voltage generating module is used to output a DC high voltage, which is applied to one end of the cable under test and one end of the reference resistor respectively. The other end of the cable under test and the other end of the reference resistor are connected to the first input terminal and the second input terminal of the comparison module respectively. The comparison module compares the voltages at the first input terminal and the second input terminal. The reference resistor provides a reference voltage for the comparison module. The insulation resistance of the cable under test can reflect the insulation performance of the cable. If the insulation performance of the cable under test is different, the voltage at the first input terminal of the comparison module is different. For example, when the cable has good insulation performance, its resistance value is relatively large, and the voltage at the first input terminal is relatively low; while when the insulation performance is poor, the resistance value becomes smaller, and the voltage at the first input terminal will increase. The comparison module compares the voltages at these two input terminals and outputs corresponding electrical signals according to the difference in voltage magnitudes. These electrical signals directly reflect the insulation performance status of the cable under test. The central control module receives the electrical signals output from the comparison module and processes and judges them. It analyzes whether the insulation performance of the cable represented by the electrical signals meets the regulations. For example, if the central control module sets that when the electrical signal output by the comparison module exceeds a certain threshold, it means that the insulation performance of the cable is unqualified, then it will make a corresponding judgment. When the central control module judges that the insulation performance of the cable under test does not meet the regulations, it will send an alarm instruction to the alarm module. After receiving the instruction, the alarm module will issue an alarm through sound, light or other means to remind relevant personnel to pay attention. For example, in an industrial production environment, the alarm module may emit a loud alarm sound and flash a warning light to ensure that the staff can be informed of the insulation problem of the cable in a timely manner.

[0036] Exemplarily, in the power distribution room of a large factory, there is a group of important power cables that need to be regularly tested for insulation performance. In the cable insulation detection system used, the high-voltage generating module can stably output a DC high voltage of 500 volts. The output terminal of the high-voltage generating module is connected to one end of the cable under test, such as Cable A. The first input terminal of the comparison module is connected to the other end of Cable A. At the same time, the output terminal of the high-voltage generating module is also connected to the first end of a 50-ohm reference resistor, and the second end of the reference resistor is connected to the second input terminal of the comparison module. In a test, when Cable A has good insulation performance, its resistance value is as high as 500 ohms. At this time, the voltage calculated at the first input terminal of the comparison module is about 50 volts, which is significantly lower than the 250 volts input to the second input terminal of the comparison module at the other end of the reference resistor. However, as the usage time of Cable A increases and is affected by environmental factors, its insulation performance gradually deteriorates, and the resistance value drops to 100 ohms. At this time, the voltage at the first input terminal rises to about 250 volts. After the comparison module compares the voltages at the two input terminals, it outputs corresponding electrical signals to the central control module. The central control module has previously set that when the electrical signal output by the comparison module indicates that the voltage at the first input terminal exceeds 200 volts, it is determined that the insulation performance of the cable is unqualified.

[0037] Since the voltage at the first input terminal reached 250 volts during this detection, exceeding the preset threshold, the central control module determined that the insulation performance of cable A did not meet the regulations and immediately sent an alarm instruction to the alarm module. After receiving the instruction, the alarm module immediately issued an alarm through a loud alarm sound and a flashing red warning light. The staff on duty in the power distribution room took timely measures to repair or replace cable A after hearing and seeing the alarm, avoiding potential power failures and safety accidents caused by cable insulation problems.

[0038] From the above, it can be concluded that this embodiment can automatically apply a high-voltage signal, use a reference resistor to provide a stable voltage reference, accurately compare the voltage differences between the cable under test and the reference resistor through a comparison module, and quickly evaluate the cable insulation condition. Once it is found that the insulation performance does not meet the standard, the central control module immediately triggers an alarm, effectively preventing potential safety hazards. This design not only improves the detection efficiency and accuracy but also greatly enhances the safety and reliability of cable use, providing strong technical support for cable maintenance and management in fields such as electricity and communication.

[0039] As Figure 2 shown, in an embodiment of the present disclosure, the high-voltage generation module includes a pulse generation circuit, a drive circuit, a boost circuit, and a feedback circuit; the output terminal of the pulse generation circuit is connected to the input terminal of the drive circuit, the output terminal of the drive circuit is connected to the output terminal of the boost circuit, the output terminal of the boost circuit is connected to the input terminal of the feedback circuit, and the output terminal of the feedback circuit is connected to the feedback terminal of the pulse generation circuit; the output terminal of the boost circuit is used to output a high-voltage signal.

[0040] In this embodiment, the pulse generation circuit first generates pulse signals, and its output terminal transmits these pulse signals to the drive circuit. After receiving the pulse signals, the drive circuit amplifies and processes them to enhance the driving ability of the signals. The signals processed by the drive circuit are transmitted to the boost circuit, which can boost the input voltage to the required high-voltage level. The output terminal of the boost circuit outputs a high-voltage signal, and at the same time, this output terminal is also connected to the input terminal of the feedback circuit. The feedback circuit monitors and analyzes the boosted output signal and transmits the feedback information to the feedback terminal of the pulse generation circuit. The pulse generation circuit adjusts the generation of pulse signals according to the feedback information, such as changing the frequency, width, etc. of the pulses, so as to achieve precise control and stable regulation of the high-voltage signal output by the entire high-voltage generation module. For example, if the feedback circuit detects that the output high-voltage signal is too high, it will notify the pulse generation circuit through the feedback terminal to reduce the pulse frequency or width so that the high-voltage signal output by the boost circuit meets the requirements; conversely, if the output high-voltage signal is too low, the pulse generation circuit will correspondingly increase the pulse frequency or width to increase the output voltage of the boost circuit. This closed-loop feedback regulation mechanism ensures that the high-voltage generation module can stably and accurately output the required high-voltage signal.

[0041] As Figure 3 shown, in an embodiment of the present disclosure, the pulse generation circuit includes a pulse generator U1 and a resistor R3; the power supply terminal of the pulse generator U1 is used to connect to the VCC power supply, the non-inverting input terminal of the pulse generator U1 is connected to the feedback terminal of the pulse generator U1 through the resistor R3, the inverting input terminal of the pulse generator U1 is used to connect to the reference voltage, and the output terminal of the pulse generator U1 is connected to the input terminal of the drive circuit.

[0042] In this embodiment, the pulse generator U1 is used to output a PWM control signal, and the pulse generation circuit realizes the generation of the pulse signal through the cooperative work of the pulse generator U1 and the resistor R3. Specifically, the VCC power supply provides a stable working voltage for the pulse generator U1. The resistor R3 serves as a feedback element, feeding back a part of the signal at the output terminal of the pulse generator U1 to its non-inverting input terminal, and jointly constituting a negative feedback system with the reference voltage connected to the inverting input terminal. Ensure that the generated pulse signal has a stable amplitude and frequency. When the reference voltage is set, the pulse generator U1 adjusts the duty cycle or frequency of its output pulse signal according to the voltage difference (i.e., the error signal) between the inverting input terminal and the non-inverting input terminal to maintain the balance of the voltages at the two input terminals. Finally, a stable pulse signal is output from the output terminal of the pulse generator U1 and supplied to the drive circuit to provide a drive signal for the subsequent high-voltage boost process.

[0043] This embodiment uses a PWM controller with the model number SG3525AN as the pulse signal generator U1.

[0044] As Figure 3 shown, in an embodiment of the present disclosure, the drive circuit includes a resistor R1, a diode D1, a switching transistor Q1, and a switching transistor Q2; the output terminal of the resistor R1 is connected to the output terminal of the pulse generator U1, the second terminal of the resistor R1 is connected to the anode of the diode D1, the cathode of the diode D1 is connected to the control terminal of the switching transistor Q2, the anode of the diode D1 is connected to the control terminal of the switching transistor Q1, the first terminal of the switching transistor Q1 is connected to the control terminal of the switching transistor Q2, the second terminal of the switching transistor Q1 is grounded, the first terminal of the switching transistor Q2 is connected to the input terminal of the boost circuit, and the second terminal of the switching transistor Q2 is grounded.

[0045] As Figure 3As shown, in this embodiment, the pulse signal generated by the pulse generator U1 first reaches the resistor R1. The resistor R1 plays a role in current limiting, restricting and adjusting the pulse signal to a certain extent. The pulse signal after passing through the resistor R1 is transmitted to the anode of the diode D1. The diode D1 plays a role of unidirectional conduction here, enabling the signal to be transmitted in a predetermined direction. The cathode of the diode D1 is connected to the control terminal of the switching transistor Q2, and the anode is connected to the control terminal of the switching transistor Q1. When the pulse signal makes the switching transistor Q1 conduct (the pulse generator U1 outputs a low level), the potential of the control terminal of the switching transistor Q2 connected to its first end is pulled down, thereby controlling the conduction and cutoff of the switching transistor Q2. The second end of the switching transistor Q1 is grounded to form a loop. And the first end of the switching transistor Q2 is connected to the input terminal of the boost circuit. When the switching transistor Q2 conducts, current can flow smoothly into the boost circuit. When the pulse signal changes and causes the switching transistor Q1 to cutoff (the pulse generator U1 outputs a high level), the potential of the control terminal of the switching transistor Q2 rises, and the switching transistor Q2 also cutoff accordingly. Through such alternating conduction and cutoff, the effective driving of the input terminal of the boost circuit is achieved. For example, at a certain moment, the pulse signal makes the switching transistor Q1 conduct and Q2 cutoff, and current cannot flow into the boost circuit; while at the next moment, the pulse signal changes, the switching transistor Q1 cutoff and Q2 conduct, and current can be input into the boost circuit, providing a regular input signal for the boost circuit to ensure its normal operation and achieve the boost function.

[0046] As Figure 3 As shown, in an embodiment of the present disclosure, the boost circuit includes a transformer T1, a diode D2, and a capacitor C4; the first input terminal of the transformer T1 is used to connect to the VCC power supply, the second input terminal of the transformer T1 is connected to the first end of the switching transistor Q2, the first output terminal of the transformer T1 is connected to the anode of the diode D2, the second output terminal of the transformer T1 is grounded, the cathode of the diode D2 is grounded through the capacitor C4, and the cathode of the diode D2 is used to output a high-voltage signal.

[0047] In this embodiment, the first input terminal of transformer T1 is connected to the VCC power supply to provide basic input electrical energy for the circuit. When switch Q2 is turned on, current flows from its first terminal into the second input terminal of transformer T1. Transformer T1 plays the role of voltage transformation here, boosting the input voltage. The boosted AC voltage of transformer T1 is output from the first output terminal and then reaches the anode of diode D2. Diode D2 plays a rectifying role, only allowing current to pass unidirectionally, converting the AC voltage into a DC voltage. The DC voltage after being rectified by diode D2 will charge capacitor C4, and capacitor C4 plays the role of filtering and smoothing the voltage, making the output voltage more stable. Finally, the DC high voltage after being rectified by diode D2 and filtered by capacitor C4 is output from the cathode of diode D2. For example, assuming the AC voltage input to transformer T1 is 8V, after the boosting effect of transformer T1, the output AC voltage may rise to 800V, and after being rectified by diode D2 and filtered by capacitor C4, a stable 800V DC high voltage is finally output.

[0048] In this embodiment, the boost circuit realizes the efficient conversion of the low-voltage VCC power supply into a stable high-voltage signal output through the electromagnetic induction of transformer T1, the rectification of diode D2, and the filtering of capacitor C4. This conversion process not only increases the voltage level, meeting the requirements of high-voltage application scenarios such as cable insulation detection, but also ensures the stability and reliability of the output voltage through rectification and filtering, thereby improving the overall performance and safety of the cable insulation detection system.

[0049] As Figure 3 shown, in an embodiment of the present disclosure, the feedback circuit includes resistor R7, resistor R8, resistor R9, and rheostat RP1; the first terminal of resistor R7 is connected to the cathode of diode D2, the second terminal of resistor R7 is grounded through resistor R8, the second terminal of resistor R7 is connected to the first terminal of rheostat RP1 through resistor R9, the first terminal of rheostat RP1 is connected to the inverting input terminal of pulse generator U1, the sliding terminal of rheostat RP1 is connected to the compensation terminal of pulse generator U1, and the second terminal of rheostat RP1 is grounded.

[0050] In this embodiment, the first terminal of resistor R7 is connected to the cathode of diode D2 for collecting the high-voltage signal output by the boost circuit. The second terminal of resistor R7 is, on the one hand, grounded through resistor R8 to form a voltage-dividing circuit, and on the other hand, connected to the first terminal of rheostat RP1 through resistor R9.

[0051] Rheostat RP1 plays the role of adjusting the feedback amount here. Its first terminal receives the voltage-dividing signal from resistors R7 and R9, the sliding terminal is connected to the compensation terminal of pulse generator U1 for adjusting the compensation amount fed back to pulse generator U1, and the second terminal is grounded.

[0052] When the high-voltage signal output by the boost circuit changes, through the voltage division of resistors R7 and R8, the voltage transmitted to the first end of the variable resistor RP1 by resistor R9 will also change accordingly. According to the set resistance ratio relationship, the variable resistor RP1 feeds back this changing voltage to the inverting input terminal and the compensation terminal of the pulse generator U1.

[0053] The pulse generator U1 adjusts the pulse signal it outputs according to the feedback voltage signal. For example, if the feedback voltage increases, it will cause the pulse generator U1 to decrease the width of the output pulse, thereby reducing the boosting amplitude of the boost circuit; conversely, if the feedback voltage decreases, the pulse generator U1 can increase the width or frequency of the output pulse to increase the boosting amplitude of the boost circuit.

[0054] The feedback circuit can automatically adjust the output of the pulse generator U1 according to the change of the high-voltage signal output by the boost circuit, so that the output of the boost circuit remains in a relatively stable state. The adjustable nature of the variable resistor RP1 provides a certain degree of flexibility, and the appropriate feedback amount can be set according to specific circuit requirements and actual situations to achieve the best circuit performance.

[0055] As Figure 3 shown, in an embodiment of the present disclosure, the reference resistor includes resistor RL; the comparison module includes resistor R10 and operational amplifier U2; the inverting input terminal of the operational amplifier U2 serves as the first input terminal of the comparison module, the first end of the resistor RL is connected to the output terminal of the high-voltage generation module, the second end of the resistor RL is connected to the non-inverting input terminal of the operational amplifier U2, the non-inverting input terminal of the operational amplifier U2 is grounded through the resistor R10, and the output terminal of the operational amplifier U2 is connected to the central control module.

[0056] Figure 3 In, the resistor RX is used as the insulation resistance of the cable under test. One end of the resistor RL is connected to the output terminal of the high-voltage generation module, and the other end is connected to the non-inverting input terminal of the operational amplifier U2. The inverting input terminal of the operational amplifier U2 serves as the first input terminal of the comparison module and is used to receive the voltage signal at the other end of the cable under test.

[0057] When the high-voltage generation module outputs a high-voltage signal, a reference voltage is generated through the resistor RL and input to the non-inverting input terminal of the operational amplifier U2. At the same time, it is grounded through the resistor R10 to provide a stable potential reference for the non-inverting input terminal.

[0058] The operational amplifier U2 compares the voltage signal from the cable under test received at its inverting input terminal with the reference voltage received at its non-inverting input terminal. If the voltage at the inverting input terminal is higher than the voltage at the non-inverting input terminal, the operational amplifier U2 outputs a low level; conversely, if the voltage at the inverting input terminal is lower than the voltage at the non-inverting input terminal, the operational amplifier U2 outputs a high level.

[0059] The output terminal of the operational amplifier U2 is connected to the central control module, and the comparison result is transmitted to the central control module in the form of an electrical signal for further processing and judgment by the central control module.

[0060] For example, assume that the voltage across the resistor RL makes the reference voltage at the non-inverting input terminal of the operational amplifier U2 be 5V, while the voltage input to the inverting input terminal of the operational amplifier U2 from the other end of the cable under test is 3V. At this time, the operational amplifier U2 outputs a high level to the central control module, indicating that the insulation performance of the cable under test is good; if the voltage input to the inverting input terminal from the other end of the cable under test is 7V, the operational amplifier U2 outputs a low level to the central control module, indicating that there may be a problem with the insulation performance of the cable under test.

[0061] As Figure 3 shown, in an embodiment of the present disclosure, the comparison module further includes a resistor R11, an optocoupler U3, a triode Q3, and a resistor R13; the first end of the resistor R11 is connected to the output terminal of the operational amplifier U2, the second end of the resistor R11 is connected to the first input terminal of the optocoupler U3, the second output terminal of the optocoupler U3 is grounded, the first output terminal of the optocoupler U3 is used to connect to the VDD power supply, the second output terminal of the optocoupler U3 is connected to the base of the triode Q3, the collector of the triode Q3 is used to connect to the VDD power supply, the emitter of the triode Q3 is grounded through the resistor R13, and the emitter of the triode Q3 is connected to the central control module.

[0062] In this embodiment, the output terminal of the operational amplifier U2 is connected to the first end of the resistor R11. When the operational amplifier U2 outputs an electrical signal, it is transmitted to the first input terminal of the optocoupler U3 through the resistor R11. The optocoupler U3 plays a role in isolation and signal transmission. When the first input terminal of the optocoupler U3 receives a signal from the resistor R11, the light-emitting diode inside it emits light, thereby causing the second output terminal of the optocoupler U3 to conduct or cut off.

[0063] The second output terminal of the optocoupler U3 is connected to the base of the triode Q3. When the optocoupler U3 conducts, it provides current for the base of the triode Q3, causing the triode Q3 to conduct; conversely, when the optocoupler U3 cuts off, the triode Q3 cuts off. The collector of the triode Q3 is connected to the VDD power supply, and the emitter is grounded through the resistor R13. When the triode Q3 conducts, current flows from the VDD power supply through the triode Q3 and the resistor R13 to the ground. At this time, the voltage at the emitter of the triode Q3 changes. The emitter of the triode Q3 is connected to the central control module, and the processed comparison result is transmitted to the central control module in the form of a specific voltage signal.

[0064] For example, if the operational amplifier U2 outputs a high level, the optocoupler U3 is turned on, and then the triode Q3 is turned on. The emitter of the triode Q3 outputs a relatively low voltage to the central control module. If the operational amplifier U2 outputs a low level, the optocoupler U3 is turned off, and the triode Q3 is also turned off. The emitter of the triode Q3 outputs a voltage close to VDD to the central control module. In this way, the effective transmission and processing of the comparison result to the central control module are realized.

[0065] In this embodiment, by introducing the resistor R11, the optocoupler U3, the triode Q3, and the resistor R13, not only the isolation and transmission ability of the signal are enhanced, but also the reliable amplification and conversion of the comparison result are realized, and finally it is transmitted to the central control module in the form of a clear voltage signal. This design effectively avoids signal interference and false triggering, improves the stability and reliability of the system, ensures that the central control module can accurately receive and process the comparison result, and thus realizes the precise control of the output voltage of the high-voltage generation module.

[0066] The above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the present disclosure in each embodiment.

Claims

1. A cable insulation detection system, characterized in that: It includes high voltage generation module, reference resistor, comparison module, central control module and alarm module; The output end of the high voltage generating module is used to connect one end of the cable to be tested, and the first input end of the comparison module is used to connect the other end of the cable to be tested; The output end of the high voltage generating module is connected to the first end of the reference resistor, and the second end of the reference resistor is connected to the second input end of the comparison module; The high voltage generating module is used to output a high voltage signal; The output end of the comparison module is connected to the central control module, and the central control module is connected to the alarm module.

2. The cable insulation detection system according to claim 1, characterized in that: The high voltage generating module comprises a pulse generating circuit, a driving circuit, a boost circuit and a feedback circuit; The output end of the pulse generating circuit is connected to the input end of the driving circuit, the output end of the driving circuit is connected to the output end of the boosting circuit, the output end of the boosting circuit is connected to the input end of the feedback circuit, and the output end of the feedback circuit is connected to the feedback end of the pulse generating circuit; The output end of the boost circuit is used to output a high voltage signal.

3. The cable insulation detection system according to claim 2, characterized in that: The pulse generating circuit comprises a pulse generator U1 and a resistor R3; The power supply end of the pulse generator U1 is used to connect to the VCC power supply, the in-phase input end of the pulse generator U1 is connected to the feedback end of the pulse generator U1 through the resistor R3, the inverting input end of the pulse generator U1 is used to connect to the reference voltage, and the output end of the pulse generator U1 is connected to the input end of the drive circuit.

4. The cable insulation detection system according to claim 3, characterized in that: The driving circuit includes a resistor R1, a diode D1, a switch tube Q1 and a switch tube Q2; The output end of the resistor R1 is connected to the output end of the pulse generator U1, the second end of the resistor R1 is connected to the anode of the diode D1, the cathode of the diode D1 is connected to the control end of the switch tube Q2, the anode of the diode D1 is connected to the control end of the switch tube Q1, the first end of the switch tube Q1 is connected to the control end of the switch tube Q2, the second end of the switch tube Q1 is grounded, the first end of the switch tube Q2 is connected to the input end of the boost circuit, and the second end of the switch tube Q2 is grounded.

5. The cable insulation detection system according to claim 4, characterized in that: The boost circuit includes a transformer T1, a diode D2 and a capacitor C4; The first input end of the transformer T1 is used to connect to the VCC power supply, the second input end of the transformer T1 is connected to the first end of the switch tube Q2, the first output end of the transformer T1 is connected to the anode of the diode D2, the second output end of the transformer T1 is grounded, the cathode of the diode D2 is grounded through the capacitor C4, and the cathode of the diode D2 is used to output a high voltage signal.

6. The cable insulation detection system according to claim 5, characterized in that: The feedback circuit includes a resistor R7, a resistor R8, a resistor R9 and a variable resistor RP1; The first end of the resistor R7 is connected to the cathode of the diode D2, the second end of the resistor R7 is grounded through the resistor R8, the second end of the resistor R7 is connected to the first end of the variable resistor RP1 through the resistor R9, the first end of the variable resistor RP1 is connected to the inverting input end of the pulse generator U1, the sliding end of the variable resistor RP1 is connected to the compensation end of the pulse generator U1, and the second end of the variable resistor RP1 is grounded.

7. The cable insulation detection system according to claim 1, characterized in that: The reference resistor includes a resistor RL; the comparison module includes a resistor R10 and an operational amplifier U2; The inverting input terminal of the operational amplifier U2 serves as the first input terminal of the comparison module, the first end of the resistor RL is connected to the output terminal of the high voltage generating module, the second end of the resistor RL is connected to the non-inverting input terminal of the operational amplifier U2, the non-inverting input terminal of the operational amplifier U2 is grounded through the resistor R10, and the output terminal of the operational amplifier U2 is connected to the central control module.

8. The cable insulation detection system according to claim 7, characterized in that: The comparison module also includes a resistor R11, an optical coupler U3, a transistor Q3 and a resistor R13; The first end of the resistor R11 is connected to the output end of the operational amplifier U2, the second end of the resistor R11 is connected to the first input end of the optocoupler U3, the second output end of the optocoupler U3 is grounded, the first output end of the optocoupler U3 is used to connect to the VDD power supply, the second output end of the optocoupler U3 is connected to the base of the transistor Q3, the collector of the transistor Q3 is used to connect to the VDD power supply, the emitter of the transistor Q3 is grounded through the resistor R13, and the emitter of the transistor Q3 is connected to the central control module.

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