A single-phase power supply four-in-one protection device

Abstract

This utility model relates to the field of power system protection technology, and discloses a four-in-one protection device for single-phase power supply. The device includes an automatic reclosing power protector, a surge protector, and an over / under / overcurrent protection device. The automatic reclosing power protector is connected to the phase line L and neutral line N of the single-phase power supply. Its output terminal is connected to the input terminals of the surge protector and the over / under / overcurrent protection device. The PE terminal of the surge protector is grounded, and the output terminal of the over / under / overcurrent protection device is connected to the coil of a power supply relay. The normally open contact of the power supply relay is connected to the equipment power supply. The automatic reclosing power protector can automatically reclose to restore power supply after a transient overvoltage fault in the single-phase power supply; the surge protector can limit transient overvoltages; and the over / under / overcurrent protection device monitors voltage and current in real time. This utility model aims to provide an integrated, intelligent, and reliable four-in-one protection device for single-phase power supply, addressing the shortcomings of existing protection devices and meeting the diverse needs of modern power systems.

Description

Technical Field

[0001] This utility model belongs to the field of power system protection technology, specifically a single-phase power supply four-in-one protection device. Background Technology

[0002] With societal progress and rising living standards, users have increasingly higher demands for the safety and reliability of power supply. In industrial control systems, single-phase loads are widely used; for example, in vocational college electrical training labs, students frequently plug in the wrong power phase wire, easily causing equipment damage or even accidents. Furthermore, the development of smart grids requires real-time data collection, monitoring, and control of power supply information to provide users with reliable, economical, and clean power supply and value-added services. Therefore, power protection devices are needed to effectively monitor parameters such as voltage and current to ensure the safe operation of loads while meeting the development needs of smart grids.

[0003] However, existing single-phase power supply protection devices have many defects and shortcomings: First, the protection functions are incomplete. Some traditional protection devices only have basic functions such as phase loss protection and overload protection, and are unable to cope with complex faults such as over-voltage, under-voltage, overcurrent, and lightning surges, failing to meet the diverse protection needs of modern power systems. Second, the power supply reliability is low. For example, some devices use a single DC power supply. Once this power supply fails, the trip output of the protection device will fail to operate, resulting in the loss of equipment protection. Third, the environmental adaptability is poor. Many protectors have stringent requirements for the operating environment and cannot be used in harsh environments such as those with explosive hazardous media, corrosive gases, and conductive dust, limiting their application scope. Fourth, fault diagnosis and indication are unclear. Some devices lose their indication signals after a fault occurs, making it impossible to clearly identify the cause of the fault, which makes fault location and troubleshooting difficult. Fifth, the maintenance cost is high. Some devices have complex structures, are difficult to maintain, require professional technicians for maintenance, and have poor parts interchangeability, requiring customization for replacement, which increases maintenance costs and time costs. Utility Model Content

[0004] To address the above problems, this utility model provides an integrated, intelligent, and reliable four-in-one protection device for single-phase power supply, in order to overcome the shortcomings of existing protection devices and meet the diverse needs of modern power systems.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A single-phase power supply four-in-one protection device includes an automatic reclosing power protector, a surge protector, and an over / under voltage and overcurrent protector. The automatic reclosing power protector is connected to the phase line L and neutral line N of the single-phase power supply, respectively. The output terminals of the automatic reclosing power protector are connected to the input terminals of the surge protector and the over / under voltage and overcurrent protector, respectively. The PE terminal of the surge protector is grounded, and the output terminal of the over / under voltage and overcurrent protector is connected to the coil of a power supply relay. The normally open contact of the power supply relay is connected to the power supply of the equipment. The automatic reclosing power protector is used to automatically reclose and restore power supply after a circuit breaker trips due to a transient overvoltage fault in the single-phase power supply. The surge protector is used to limit transient overvoltages and prevent damage to electrical and electronic equipment due to transient overvoltages such as lightning strikes and power supply faults. The over / under voltage and overcurrent protector is used to monitor the voltage and current of the single-phase power supply in real time. When the voltage exceeds or falls below the set range, or the current exceeds the rated value, the power supply protection device is disconnected, and the power supply is automatically restored after the fault is cleared.

[0007] The beneficial effects of the above technical solution are as follows: the protection device integrates automatic reclosing, surge protection, and over / under voltage and overcurrent protection functions into one, which can comprehensively protect the single-phase power supply system, avoid equipment damage caused by various faults, improve power supply reliability and continuity, reduce power outage time, reduce equipment maintenance and replacement costs, and at the same time reduce the installation space and cost of single-function protection device combinations.

[0008] As a further improvement to the above scheme, the voltage setting range of the automatic reclosing power protection device is 300V-110V, and the current setting range is 0-60A.

[0009] The beneficial effects of the above technical solution are as follows: by setting the voltage and current range of the automatic reclosing power protection device, it can adapt to the working environment of different single-phase power supplies, improve its applicability and flexibility, and better meet user needs.

[0010] As a further improvement to the above solution, surge protectors protect electrical and electronic equipment from damage caused by lightning surges by limiting surge voltage.

[0011] The beneficial effects of the above technical solution are as follows: surge protectors can effectively prevent damage to equipment caused by transient overvoltages such as lightning strikes and power failures, extend the service life of equipment, and reduce equipment maintenance and replacement costs. Especially in areas with frequent lightning strikes, they can better protect home appliances such as computers and televisions.

[0012] As a further improvement to the above scheme, the leakage current action value of the over / under voltage and overcurrent protector is adjustable from 10mA to 90mA; when the supply current is greater than or equal to 5 times the rated current, the over / under voltage and overcurrent protector will trip and cut off the power supply within 0.1 seconds; when an overcurrent lasts for more than 2 seconds, the over / under voltage and overcurrent protector will trip; when the input voltage is greater than 300V, the first layer of protection will be disconnected, and when it is greater than 240V, the second layer of protection will trip, with an action time of 1 second; when the input voltage is less than 190V, the over / under voltage and overcurrent protector will trip, with an action time of 1 second.

[0013] The beneficial effects of the above technical solution are as follows: the overvoltage and undervoltage overcurrent protector has an adjustable leakage current action value, which can be flexibly adjusted according to actual needs to improve protection accuracy; the fast action characteristic enables it to cut off the power supply in time when the current is abnormal, effectively protect the equipment, reduce the risk of equipment damage due to overcurrent, overvoltage and undervoltage and other faults, and improve electrical safety.

[0014] As a further improvement to the above scheme, the automatic reclosing power protection device and the surge protection device can work together to provide the first layer of overvoltage protection; the overvoltage and undervoltage overcurrent protection device can provide the second layer of protection to ensure the reliability of power supply for military products or industrial use.

[0015] The beneficial effects of the above technical solutions are as follows: the two work together as the first layer of overvoltage protection, which can more effectively deal with transient overvoltage and transient overvoltage faults, forming a dual protection mechanism, improving protection effect and reliability, and further reducing the possibility of equipment damage due to overvoltage; the overvoltage and undervoltage overcurrent protectors, as the second layer of protection, can provide more reliable and accurate protection for military products or industrial power supply, effectively deal with complex faults such as three-phase imbalance and overload, meet the high requirements of power supply reliability in special fields, and ensure the normal operation of important equipment.

[0016] As a further improvement to the above solution, the over / under voltage and overcurrent protector includes:

[0017] A resistor step-down module, whose input terminal is connected to the single-phase power supply, is used to step down the input voltage and output it to the overvoltage monitoring and indication circuit and the undervoltage monitoring and indication circuit.

[0018] An overvoltage monitoring and indication circuit is connected to the output terminal of the resistor step-down module to monitor whether the voltage exceeds the set upper limit and trigger the corresponding indicator light when overvoltage occurs.

[0019] An undervoltage monitoring and indication circuit is connected to the output terminal of the resistor step-down module to monitor whether the voltage is lower than the set lower limit and to trigger the corresponding indicator light when undervoltage occurs.

[0020] A 12V voltage regulator circuit is connected to the output terminal of the resistor step-down module to provide a stable 12V DC voltage to the buzzer alarm circuit and the relay drive circuit.

[0021] A buzzer alarm circuit is connected to the 12V voltage regulator circuit and is used to emit an alarm sound when there is overvoltage or undervoltage.

[0022] A relay drive circuit, connected to the overvoltage monitoring and indication circuit and the undervoltage monitoring and indication circuit, is used to control the on / off state of the power supply relay coil in case of overvoltage or undervoltage, thereby cutting off or restoring power supply. The coil of the power supply relay is connected to the device power supply to control the on / off state of power supply.

[0023] The beneficial effects of the above technical solution are as follows:

[0024] By implementing a two-layer protection structure, comprehensive protection for single-phase power supplies is achieved. The first layer of protection consists of an automatic reclosing circuit breaker and a surge protector, effectively addressing transient overvoltage and momentary overvoltage faults, forming a dual protection mechanism that improves protection effectiveness and reliability. The second layer of protection is provided by over / undervoltage and overcurrent protectors. These protectors not only offer more reliable and precise protection for military products or industrial power supplies, effectively addressing complex faults such as three-phase imbalance and overload, ensuring the normal operation of critical equipment, but also automatically restore power supply after fault clearance, reducing power outage time, improving power supply continuity and stability, and further enhancing the reliability and continuity of equipment power supply. This rationally structured and comprehensively functional protection design effectively reduces the risk of equipment damage due to overvoltage, overcurrent, and other problems, extends equipment lifespan, and reduces maintenance costs.

[0025] The overall beneficial effects of this utility model compared with the prior art are as follows:

[0026] This single-phase power supply four-in-one protection device integrates multiple protection functions, comprehensively solving the problems of incomplete protection functions, low reliability, poor environmental adaptability, unclear fault diagnosis, and high maintenance costs of existing single-phase power supply protection devices. Its intelligent and automated protection mechanism can effectively cope with various complex power system faults, improve power supply reliability and equipment lifespan, reduce maintenance costs and power outage losses, and has significant technical advantages and practical value. It can be widely used in various single-phase power supply systems to meet the power safety needs of different scenarios. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the front structure of the device housing.

[0028] Figure 2 This is a schematic diagram of the internal structure of the device.

[0029] Figure 3This is a schematic diagram of the circuit modules of this device.

[0030] Figure 4 This is the circuit diagram of this device.

[0031] In the diagram: 1. Automatic reclosing power protection device; 2. Surge protector; 3. Over / under voltage and overcurrent protector; 4. Power supply relay. Detailed Implementation

[0032] To enable those skilled in the art to better understand the technical solution, the present invention will be described in detail below with reference to the embodiments. The description in this part is only exemplary and explanatory, and should not be used to limit the scope of protection of the present invention in any way.

[0033] The structure and connection method of this device are as follows:

[0034] like Figures 1-2 As shown, this utility model is a single-phase power supply four-in-one protection device, which mainly consists of an automatic reclosing power protector 1, a surge protector 2, an over / under voltage and overcurrent protector 3, and a power supply relay 4.

[0035] Figure 1 The diagram shows the front view of the device's housing, where a power indicator light is located.

[0036] Figure 2 A schematic diagram of the internal hardware connection structure of this device is shown.

[0037] The automatic reclosing power protector 1 has its phase line L and neutral line N connected to the single-phase power supply, respectively. The automatic reclosing power protector 1 has two output terminals: one connected to the input terminal of surge protector 2, and the other connected to the input terminal of overvoltage / undervoltage / overcurrent protector 3. The PE terminal of surge protector 2 is grounded. The output terminal of overvoltage / undervoltage / overcurrent protector 3 is connected to the coil of power supply relay 4, and the normally open contact of power supply relay 4 is connected to the equipment power supply. Additionally, the output terminal of automatic reclosing power protector 1 is also connected to both ends of a panel indicator light to display normal and overvoltage values.

[0038] The over / under voltage and overcurrent protector 3 includes:

[0039] A resistor step-down module, whose input terminal is connected to the single-phase power supply, is used to step down the input voltage and output it to the overvoltage monitoring and indication circuit and the undervoltage monitoring and indication circuit.

[0040] An overvoltage monitoring and indication circuit is connected to the output terminal of the resistor step-down module to monitor whether the voltage exceeds the set upper limit and trigger the corresponding indicator light when overvoltage occurs.

[0041] An undervoltage monitoring and indication circuit is connected to the output terminal of the resistor step-down module to monitor whether the voltage is lower than the set lower limit and to trigger the corresponding indicator light when undervoltage occurs.

[0042] A 12V voltage regulator circuit is connected to the output terminal of the resistor step-down module to provide a stable 12V DC voltage to the buzzer alarm circuit and the relay drive circuit.

[0043] A buzzer alarm circuit is connected to the 12V voltage regulator circuit and is used to emit an alarm sound when there is overvoltage or undervoltage.

[0044] A relay drive circuit, connected to the overvoltage monitoring and indication circuit and the undervoltage monitoring and indication circuit, is used to control the on / off state of the power supply relay 4 coil in case of overvoltage or undervoltage, thereby cutting off or restoring power supply. The coil of the power supply relay 4 is connected to the device power supply to control the on / off state of power supply.

[0045] Specifically, the resistor step-down module includes resistors R1, R2, R3, R4, R5, R6 and capacitor C1. One end of resistor R1 is connected to the phase line L of the single-phase power supply, and the other end is connected to the positive input terminal of operational amplifier IC1A and the positive input terminal of operational amplifier IC1B. One end of resistor R2 is connected to the output terminal of operational amplifier IC1A, and the other end is connected to the inverting input terminal of operational amplifier IC1B. Resistor R3 is connected between the output terminal of operational amplifier IC1B and the relay drive circuit. Resistor R4 is connected to the positive input terminal of operational amplifier IC1C. Resistor R5 is connected to the inverting input terminal of operational amplifier IC1C. Resistor R6 is connected to the output terminal of operational amplifier IC1F and grounded. Capacitor C1 is connected in parallel across resistor R1.

[0046] The overvoltage monitoring and indication circuit includes an adjustable resistor RP1 and operational amplifiers IC1A and IC1C. One end of the adjustable resistor RP1 is connected to the positive input terminal of operational amplifier IC1A, and the other end is connected to the positive input terminal of operational amplifier IC1C. The output terminal of operational amplifier IC1A is connected to indicator LED1.

[0047] The undervoltage monitoring and indication circuit includes an adjustable resistor RP2 and an operational amplifier IC1B. One end of the adjustable resistor RP2 is connected to the positive input terminal of the operational amplifier IC1B, and the other end is grounded.

[0048] The 12V voltage regulator circuit includes capacitors C2, C3, and C4, diodes VDW and VD7, and voltage regulators IC1E and IC1F. Capacitors C2, C3, and C4 are used for filtering, diodes VDW and VD7 are used for rectification, and voltage regulators IC1E and IC1F are used to provide a stable 12V DC voltage.

[0049] The buzzer alarm circuit includes a buzzer YD, a resistor R5, and a capacitor C4. The buzzer YD is powered by a 12V voltage regulator circuit, and the resistor R5 and capacitor C4 are used to control the duration and intensity of the alarm sound.

[0050] The relay drive circuit includes a relay coil k and a transistor VT1. The base of the transistor VT1 is connected to the output terminal of the operational amplifier IC1C, and the collector is connected to one end of the relay coil k. The other end of the relay coil k is connected to the power supply.

[0051] like Figures 3-4 The following is the circuit diagram of this device:

[0052] 1. AC input:

[0053] 220V AC power is input to the resistor step-down module.

[0054] 2. Resistor step-down module:

[0055] The 220V AC power is stepped down using resistors (R1, R2, R3, R4, R5, R6) and capacitors (C1, C2, C3, C4).

[0056] The output voltage after step-down is supplied to the overvoltage monitoring and indication circuit, the undervoltage monitoring and indication circuit, and the 12V voltage regulator circuit.

[0057] 3. Overvoltage monitoring and indication circuit:

[0058] Use an adjustable resistor (RP1) and operational amplifiers (IC1:A, IC1:C) to monitor whether the voltage exceeds the set upper limit.

[0059] When an overvoltage is detected, the red LED1 indicator light will illuminate, and the relay module will be triggered to cut off the power supply output.

[0060] 4. Undervoltage monitoring and indication circuit:

[0061] Use an adjustable resistor (RP2) and an operational amplifier (IC1:B) to monitor whether the voltage is below the set lower limit.

[0062] When undervoltage is detected, the green LED2 indicator light will illuminate, and the relay module will be triggered to cut off the power supply output.

[0063] 5.12V voltage regulator circuit:

[0064] A stable 12V DC voltage is provided using capacitors (C2, C3, C4), diodes (VDW, VD7), and voltage regulators (IC1:E, IC1:F).

[0065] Power is supplied to the buzzer alarm circuit and relay module.

[0066] 6. Buzzer alarm circuit:

[0067] When overvoltage or undervoltage is detected, the buzzer (YD) sounds an alarm.

[0068] Powered by a 12V regulated circuit, the duration and intensity of the alarm sound are controlled by a resistor (R5) and a capacitor (C4).

[0069] 7. Relay Module:

[0070] The power supply output is controlled by a relay coil (k) and a transistor (VT1).

[0071] When the overvoltage or undervoltage monitoring circuit is triggered, the relay coil is energized, cutting off the power supply output.

[0072] 8. Power supply output:

[0073] It provides a stable 220V AC power output, which is supplied to the load after passing through the protection circuit.

[0074] The on / off state is controlled by a relay module.

[0075] Working principle:

[0076] When a single-phase power supply experiences a transient overvoltage fault (such as lightning strike, transient short circuit, etc.) that causes the circuit breaker to trip, the automatic reclosing power protection device 1 can automatically reclose the circuit breaker, restore power supply, reduce power outage time, and improve power supply reliability.

[0077] Surge protectors effectively limit transient overvoltages, keeping surge voltages within the equipment's tolerance range. This prevents damage to electrical and electronic equipment caused by lightning strikes, power failures, or other transient overvoltages, extending equipment lifespan and reducing maintenance and replacement costs. In areas with frequent lightning strikes, installing surge protectors can protect household appliances such as computers and televisions from lightning surge damage. Automatic reclosing circuit breakers and surge protectors provide the first layer of overvoltage protection.

[0078] The over / under voltage and overcurrent protector 3 can monitor the voltage and current of a single-phase power supply in real time. When the voltage exceeds or falls below the set normal range (voltage setting range: 300V-110V), or the current exceeds the rated value (current setting range: 0-60A), the protector will promptly trip and cut off the power supply to protect the equipment. Power supply can be automatically restored after the fault is cleared. It can also effectively detect and protect against three-phase imbalance, overload, and other faults.

[0079] To ensure the reliability of power supply for military products or industrial applications, over / under voltage and overcurrent protectors serve as a second layer of protection. When the input voltage exceeds 300V, the first layer of protection trips; when it exceeds 240V, the second layer of protection trips, typically with an action time of 1 second. When the input voltage is less than 190V, the protector trips, with an action time of 1 second. When the supply current is greater than or equal to 5 times the rated current, the over / under voltage and overcurrent protector will trip and cut off the power supply within 0.1 seconds. When an overcurrent lasts for more than 2 seconds, the over / under voltage and overcurrent protector will trip. The leakage current action value is adjustable from 10mA to 90mA. After the fault is cleared, the automatic reclosing power protector will automatically reclose and restore power after a 5-second interval.

[0080] The experimental data are as follows:

[0081] 1. Leakage current trip value: 10mA-90mA adjustable;

[0082] 2. Short circuit protection: When the power supply current is greater than or equal to 5 times the rated current, the protector will activate within 0.1 seconds and trip to cut off the power supply.

[0083] 3. Overcurrent tripping time: When an overcurrent lasts for more than 2 seconds, the protector will trip.

[0084] 4. Overvoltage protection: When the input voltage is greater than 300V, the first layer of protection will disconnect; when it is greater than 240V, the second layer of protection will trip. The action time is generally 1 second.

[0085] 5. Undervoltage protection: When the input voltage is less than 190V, the protector will trip, with an action time of 1 second;

[0086] 6. Automatic reclosing: After the fault is cleared, the circuit will automatically reclose and power on after a 5-second interval.

[0087] It should be noted that, in this document, the terms "comprising," "including," and any other variations are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Specific examples have been used in this document to illustrate the principles and implementation methods of the present invention. These examples are merely for the purpose of helping to understand the method and core ideas of the present invention. The above are only preferred embodiments of the present invention. It should be pointed out that, due to the limitations of written expression and the objective existence of infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the concept and technical solution of the present invention to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A single-phase power supply four-in-one protection device, characterized in that, It includes an automatic reclosing power protection device (1), a surge protector (2), and an over / under voltage and overcurrent protector (3); the automatic reclosing power protection device (1) is connected to the phase line L and neutral line N of the single-phase power supply respectively, the output terminal of the automatic reclosing power protection device (1) is connected to the input terminal of the surge protector (2) and the over / under voltage and overcurrent protector (3) respectively, the PE terminal of the surge protector (2) is grounded, the output terminal of the over / under voltage and overcurrent protector (3) is connected to the coil of the power supply relay (4), and the normally open contact of the power supply relay (4) is connected to the equipment power supply.

2. The single-phase power supply four-in-one protection device according to claim 1, characterized in that, The voltage setting range of the automatic reclosing power protection device (1) is 300V~110V, and the current setting range is 0~60A.

3. The single-phase power supply four-in-one protection device according to claim 1, characterized in that, The leakage current action value of the overvoltage and undervoltage overcurrent protector (3) is adjustable from 10mA to 90mA, and its output terminal is connected to the coil of the power supply relay (4); the overvoltage and undervoltage overcurrent protector (3) can cut off the power supply when the input voltage is greater than 300V, greater than 240V, or less than 190V, or when the power supply current is greater than or equal to 5 times the rated current and the duration is greater than or equal to 2 seconds; the automatic reclosing power protector (1) can automatically reclose the circuit and power on within 5 seconds after the fault is cleared.

4. A single-phase power supply four-in-one protection device according to claim 1, characterized in that, The automatic reclosing power protection device (1) and surge protection device (2) constitute the first layer of overvoltage protection; the overvoltage and undervoltage overcurrent protection device (3) constitutes the second layer of protection.

5. A single-phase power supply four-in-one protection device according to any one of claims 1 to 4, characterized in that, The over / under voltage and overcurrent protection device (3) includes: A resistor step-down module, whose input terminal is connected to the single-phase power supply, is used to step down the input voltage and output it to the overvoltage monitoring and indication circuit and the undervoltage monitoring and indication circuit. An overvoltage monitoring and indication circuit is connected to the output terminal of the resistor step-down module to monitor whether the voltage exceeds the set upper limit and trigger the corresponding indicator light when overvoltage occurs. An undervoltage monitoring and indication circuit is connected to the output terminal of the resistor step-down module to monitor whether the voltage is lower than the set lower limit and to trigger the corresponding indicator light when undervoltage occurs. A 12V voltage regulator circuit is connected to the output terminal of the resistor step-down module to provide a stable 12V DC voltage to the buzzer alarm circuit and the relay drive circuit. A buzzer alarm circuit is connected to the 12V voltage regulator circuit and is used to emit an alarm sound when there is overvoltage or undervoltage. The relay drive circuit is connected to the overvoltage monitoring and indication circuit and the undervoltage monitoring and indication circuit, and is used to control the on / off state of the power supply relay (4) coil when there is overvoltage or undervoltage, thereby cutting off or restoring the power supply. The coil of the power supply relay (4) is connected to the equipment power supply to control the on / off state of the power supply.

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