A junction box intelligent power supply protection device

Abstract

This utility model belongs to the field of power equipment technology, specifically relating to an intelligent power supply protection device for a junction box. It includes a central processing unit, a current transformer, a voltage transformer, a temperature sensor, and a zero-sequence current transformer connected to the central processing unit via a signal conditioning circuit; a switch output module, a communication module, and a human-machine interface module interconnected with the central processing unit; the signal conditioning circuit includes a filter circuit, a signal amplification circuit, and a comparator circuit; the signals from the current transformer, voltage transformer, temperature sensor, and zero-sequence current transformer are input to the filter circuit; the output of the filter circuit is connected to the input of the comparator circuit via the signal amplification circuit; the output of the comparator circuit is connected to the central processing unit; the switch output module is connected to a relay. This utility model features high intelligence, high protection accuracy, the ability to record electrical parameters at the time of fault occurrence, assistance in locating fault points, remote monitoring, early warning, and traceable fault data.

Description

Technical Field

[0001] This utility model belongs to the field of power equipment technology, and specifically relates to an intelligent power supply protection device for junction boxes. Background Technology

[0002] Junction boxes are primarily used for connecting and branching electrical circuits. However, during use, loose internal cable joints, aging insulation, or moisture can cause the casing to become electrified. If the power is not cut off in time, this can easily lead to electric shock. If the junction box is subjected to a load exceeding the rated current for an extended period, it can cause cables to overheat, insulation to age, and even fire. When the terminal blocks inside the box short-circuit, the short-circuit current can reach tens of times the rated current, instantly generating high temperatures that melt metal components. Therefore, junction box power supply protection is introduced. Junction box power supply protection devices are a crucial component in ensuring the safe operation of power supply lines in electrical systems. They primarily prevent safety accidents caused by overload, short circuits, grounding faults, and other problems by rationally configuring protection devices, optimizing wiring design, and adhering to specifications.

[0003] However, existing traditional junction box power supply protection devices have low intelligence and low protection accuracy. Their fixed settings are easily affected by various factors such as the environment, and they cannot determine the location of the fault. Daily operation and maintenance rely on manual inspection and troubleshooting, which is difficult.

[0004] Therefore, the above-mentioned problems have become technical issues that urgently need to be solved. Utility Model Content

[0005] Purpose of the utility model: In order to overcome the above shortcomings, this utility model provides an intelligent power supply protection device for junction boxes, which aims to solve the above technical problems.

[0006] Technical solution: In order to achieve the above objectives, this utility model provides an intelligent power supply protection device for junction boxes, including a central processing unit, and a current transformer, a voltage transformer, a temperature sensor and a zero-sequence current transformer connected to the central processing unit through a signal conditioning circuit.

[0007] The switch output module, communication module, and human-machine interaction module are interconnected with the central processing unit;

[0008] The signal conditioning circuit includes a filter circuit, a signal amplification circuit, and a comparator circuit. The signals from the current transformer, voltage transformer, temperature sensor, and zero-sequence current transformer are connected to the input terminal of the filter circuit. The output terminal of the filter circuit is connected to the input terminal of the comparator circuit through the signal amplification circuit. The output terminal of the comparator circuit is connected to the central processing unit.

[0009] The digital output module is connected to the relay.

[0010] Current transformers, voltage transformers, and zero-sequence current transformers detect the current signal, voltage signal, and vector sum of the three-phase current in the feeder line, respectively. These signals are then processed by a filter circuit and a signal amplification circuit before being input to a comparator circuit and compared with an overload threshold. If the threshold is exceeded, the comparator circuit outputs a high level to the central processing unit, which then sends a signal to control the switch output module to drive a relay and trigger the protection action.

[0011] Furthermore, the central processing unit is connected to a digital input module that acquires the on / off status signals of relay contacts. The digital input module converts the acquired external digital signals into electrical signals that the central processing unit can recognize.

[0012] Furthermore, the central processing unit is also connected to a power supply module that provides DC power to each functional module through a rectifier and transformer.

[0013] Furthermore, the human-computer interaction module includes an LCD screen for displaying the device's operating parameters and fault information, and a keyboard for users to set parameters and control operations.

[0014] Furthermore, the communication module communicates and interconnects with the background monitoring system through an interface.

[0015] Furthermore, the switch output module is also connected to an alarm module. The control signal from the central processing unit is converted into a switch output by the switch output module, driving the external alarm module to issue an alarm.

[0016] Furthermore, the central processing unit is a microcontroller with integrated A / D conversion function.

[0017] As can be seen from the above technical solution, this utility model has the following beneficial effects:

[0018] This utility model provides an intelligent power supply protection device for junction boxes, which is highly intelligent. It uses digital algorithms to calculate and determine faults with high accuracy. The communication module can upload electrical parameters to the background monitoring system when a fault occurs to assist in locating the fault point. At the same time, it can receive control commands and parameter settings issued by the background monitoring system to realize remote monitoring and management. Attached Figure Description

[0019] Figure 1 This is a structural schematic diagram of a junction box intelligent power supply protection device according to the present invention. Detailed Implementation

[0020] It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0021] like Figure 1As shown: A junction box intelligent power supply protection device includes a central processing unit, a current transformer, a voltage transformer, a temperature sensor and a zero-sequence current transformer connected to the central processing unit through a signal conditioning circuit.

[0022] The switch output module, communication module, and human-machine interaction module are interconnected with the central processing unit;

[0023] The signal conditioning circuit includes a filter circuit, a signal amplification circuit, and a comparator circuit. The signals from the current transformer, voltage transformer, temperature sensor, and zero-sequence current transformer are connected to the input terminal of the filter circuit. The output terminal of the filter circuit is connected to the input terminal of the comparator circuit through the signal amplification circuit. The output terminal of the comparator circuit is connected to the central processing unit.

[0024] The digital output module is connected to the relay.

[0025] The central processing unit is connected to a switch input module that collects the on / off status signals of relay contacts.

[0026] According to a preferred embodiment of this utility model, the central processing unit is further connected to a power supply module that provides DC power to each functional module via a rectifier transformer. Simultaneously, a filter plate and voltage regulator circuit can be integrated into the power supply module to eliminate the effects of voltage fluctuations and harmonic interference in the power grid, preventing malfunctions or failures of protection devices due to power instability. Overvoltage protection, overcurrent protection, short-circuit protection, and overheat protection functions can also be integrated; when the power supply module itself malfunctions, it can automatically cut off the output to prevent the fault from escalating.

[0027] Specifically, the human-computer interaction module includes an LCD screen for displaying the device's operating parameters and fault information, and a keyboard for users to set parameters and control operations.

[0028] The communication module communicates with the back-end monitoring system via an interface. It uploads the device's operating data and fault information to the back-end monitoring system, while simultaneously receiving control commands and parameter settings from the system, enabling remote monitoring and management. It also records historical data (such as current, voltage, and temperature curves) and uses big data analysis to predict potential faults and assist in locating fault points.

[0029] Specifically, the switch output module is also connected to an alarm module.

[0030] Preferably, the central processing unit is a microcontroller with integrated A / D conversion function.

[0031] The intelligent power supply protection device for junction boxes provided in this embodiment has the following functions:

[0032] Overload protection: The current signal in the circuit is continuously monitored by a current transformer. The current signal is compared with a preset value in the comparator circuit. If the current exceeds the threshold for a preset time, it is determined to be an overload. The central processing unit controls the switch output module to drive the relay to cut off the circuit after a delay. At the same time, the overload duration and current value are recorded and uploaded to the background monitoring system through the communication module.

[0033] Overvoltage / undervoltage protection:

[0034] The voltage signal in the circuit is continuously monitored by a voltage transformer. The voltage signal is compared with a preset value in a comparator circuit. If the voltage exceeds the high threshold, it is determined to be overvoltage; if it is below the low threshold, it is determined to be undervoltage. The central processing unit controls the switch output module to drive the relay to cut off the circuit when there is overvoltage and cut off the power supply when there is undervoltage. At the same time, the voltage value is recorded and uploaded to the background monitoring system through the communication module.

[0035] Short circuit protection:

[0036] When the current in the circuit suddenly rises to 5-8 times the threshold, and the rate of rise exceeds the threshold, it is determined to be a short circuit. "Instantaneous action" or "short-delay action" is used to distinguish between instantaneous short circuit and permanent short circuit.

[0037] Leakage protection:

[0038] The vector sum of the three-phase currents is monitored by a zero-sequence current transformer. Under normal conditions, the vector sum is zero. When there is leakage, a zero-sequence current is generated. If the leakage current exceeds the threshold and the duration exceeds the set value, the protection action is triggered.

[0039] Temperature protection:

[0040] Temperature sensors monitor the temperature of critical components, and trigger protection actions if the temperature exceeds a threshold.

[0041] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of the present utility model, and these improvements should also be considered within the protection scope of the present utility model.

Claims

1. A smart feeder protection device for a junction box, characterized in that, It includes a central processing unit, and current transformers, voltage transformers, temperature sensors, and zero-sequence current transformers connected to the central processing unit via signal conditioning circuits. The switch output module, communication module, and human-machine interaction module are interconnected with the central processing unit; The signal conditioning circuit includes a filter circuit, a signal amplification circuit, and a comparator circuit. The signals from the current transformer, voltage transformer, temperature sensor, and zero-sequence current transformer are connected to the input terminal of the filter circuit. The output terminal of the filter circuit is connected to the input terminal of the comparator circuit through the signal amplification circuit. The output terminal of the comparator circuit is connected to the central processing unit. The digital output module is connected to the relay.

2. The intelligent feeder protection device for a junction box according to claim 1, characterized in that, The central processing unit is connected to a switch input module that collects the on / off status signals of relay contacts.

3. The intelligent feeder protection device for a junction box of claim 1, wherein, The central processing unit is also connected to a power supply module that provides DC power to each functional module through a rectifier and transformer.

4. The intelligent feeder protection device for a junction box of claim 1, wherein, The human-computer interaction module includes an LCD screen for displaying the device's operating parameters and fault information, and a keyboard for users to set parameters and control operations.

5. The intelligent feeder protection device for a junction box of claim 1, wherein, The communication module communicates and interconnects with the background monitoring system through an interface.

6. The intelligent feeder protection device for a junction box of claim 1, wherein, The switch output module is also connected to an alarm module.

7. The intelligent feeder protection device for a junction box of claim 1, wherein, The central processing unit is a microcontroller with integrated A / D conversion function.

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