Open-phase protection circuit structure based on voltage detection

Abstract

The utility model discloses an open-phase protection circuit structure based on voltage detection. The open-phase protection circuit structure comprises a voltage detection module and a control module, the voltage detection module is connected with the control module; the voltage detection module detects power supply voltage through a phase detection unit, converts the power supply voltage into an electronic signal and transmits the electronic signal to the control module for processing; the control module is used for receiving the signal from the voltage detection module and controlling the operation and closing of the equipment according to the signal; the low-cost photoelectric coupler is adopted for isolation and real-time monitoring of the voltage of the three-phase output end of the three-phase relay, once it is found that a certain phase voltage signal is lost, phase loss can be rapidly judged, and when phase loss is detected, the control module starts protection measures, namely, the relay is disconnected, a power supply is closed, and a warning signal is sent out so as to avoid equipment damage; the device has the advantages of high detection precision, good protection effect, low cost, high stability and the like, and can timely discover phase loss faults and prevent equipment from being damaged due to phase loss.

Description

Technical Field

[0001] The utility model relates to the technical field related to electric energy meters, and in particular to a phase loss protection circuit structure based on voltage detection. Background Art

[0002] In three-phase smart meters with load switches, relays are currently commonly used as load switches. There are integrated three-phase relays and split relays on the market, but when a phase relay is damaged by electric shock or not closed, it will cause a phase failure in the rear-end load. If the rear-end load is an electrical device such as a motor that does not allow phase loss to occur, it will cause damage to the load equipment or personal injury, causing serious losses; therefore, designing an effective and low-cost phase loss protection circuit structure based on voltage detection is an urgent need at present. Utility Model Content

[0003] The purpose of the utility model is to provide a phase loss protection circuit structure based on voltage detection, which monitors the voltage of the three-phase output terminal of the three-phase relay in real time. Once a phase voltage signal is found to be missing, it can be quickly determined as a phase loss. The utility model has the advantages of high detection accuracy, good protection effect, low cost and good stability.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a phase-loss protection circuit structure based on voltage detection, including a voltage detection module and a control module;

[0005] The voltage detection module is connected to the control module;

[0006] The voltage detection module detects the power supply voltage through the phase detection unit, converts it into an electronic signal and transmits it to the control module for processing;

[0007] The control module receives the signal from the voltage detection module and controls the operation and shutdown of the device according to the signal.

[0008] Preferably, the phase detection unit is controlled and detected by a phase loss detection circuit.

[0009] Preferably, the phase loss detection circuit is further connected to an alarm device; the alarm device performs corresponding feedback according to the signal given by the phase loss detection circuit.

[0010] Preferably, the phase loss detection circuit includes a photocoupler; the photocoupler is provided with four pins, namely a first pin, a second pin, a third pin and a fourth pin; the first pin is connected in series with a first diode; the second pin is connected in series with a second diode, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor in sequence; the third pin is directly grounded; the fourth pin is connected in series with a sixth resistor.

[0011] In a preferred solution, a third diode and a seventh resistor are further connected in parallel between the first pin and the second pin.

[0012] Preferably, the first pin, the second pin and the fourth pin of the photoelectric coupler are respectively used to monitor the three-phase output terminal voltage of the three-phase relay in real time.

[0013] Due to the application of the above technical solution, the beneficial effects of the present application compared with the prior art are:

[0014] The present application discloses a phase-loss protection circuit structure based on voltage detection, which uses a low-cost optocoupler for isolation and monitors the voltage at the three-phase output terminals of a three-phase relay in real time. Once a voltage signal of a certain phase is found to be missing, it can be quickly determined as a phase loss. When a phase loss is detected, the control module will start protection measures, namely, disconnect the relay, turn off the power supply, and send out a warning signal to avoid damage to the equipment. The structure has the advantages of high detection accuracy, good protection effect, low cost, and strong stability. By quickly detecting the power supply voltage at the rear end of the relay, the phase-loss fault can be detected in time to avoid damage to the equipment due to phase loss. The control module will immediately stop the equipment when a phase-loss fault is detected, avoiding the potential safety hazards caused by the equipment continuing to operate in a phase-loss state. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Attached Figure 1 It is a schematic diagram of the phase loss protection circuit structure based on voltage detection of the utility model;

[0017] Attached Figure 2 This is a schematic diagram of a phase loss detection circuit of the utility model;

[0018] Attached Figure 3 It is a schematic diagram of the working detection of the photoelectric coupler of the utility model;

[0019] Among them: 1. voltage detection module; 2. control module; 3. phase detection unit; 4. phase loss detection circuit; 5. alarm device; 6. photoelectric coupler; 7. first pin; 8. second pin; 9. third pin; 10. fourth pin; 11. first diode; 12. second diode; 13. first resistor; 14. second resistor; 15. third resistor; 16. fourth resistor; 17. fifth resistor; 18. sixth resistor; 19. third diode; 20. seventh resistor. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] In this application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the utility model and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0023] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in this utility model can be understood according to specific circumstances.

[0024] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0025] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] Embodiment 1

[0027] Attached Figure 1-3 The utility model is a phase-loss protection circuit structure based on voltage detection, comprising a voltage detection module 1 and a control module 2;

[0028] The voltage detection module 1 is connected to the control module 2;

[0029] The voltage detection module 1 detects the power supply voltage through the phase detection unit 3, and converts it into an electronic signal and transmits it to the control module 2 for processing; the phase detection unit 3 is controlled and detected by the phase loss detection circuit 4; the phase loss detection circuit 4 is also connected to an alarm device 5; the alarm device 5 performs corresponding feedback according to the signal given by the phase loss detection circuit 4; the phase loss detection circuit 4 includes a photoelectric coupler 6; the photoelectric coupler 6 has four pins, namely a first pin 7, a second pin 8, a third pin 9 and a fourth pin 10; the first pin 7 is connected in series with a first diode 11; the second pin 8 is connected in series with a second diode 12, a first resistor 13, a second resistor 14, a third resistor 15, a fourth resistor 16 and a fifth resistor 17; the third pin 9 is directly grounded; the fourth pin 10 is connected in series with a sixth resistor 18; a third diode 19 and a seventh resistor 20 are also connected in parallel between the first pin 7 and the second pin 8; the first pin 7, the second pin 8 and the fourth pin 10 of the photoelectric coupler 6 are respectively used for real-time monitoring of the three-phase output terminal voltage of the three-phase relay.

[0030] The control module 2 receives the signal from the voltage detection module 1 and controls the operation and shutdown of the device according to the signal.

[0031] Specifically, during the detection, the photoelectric coupler 6 samples the voltage of phase A of the relay. If a phase loss occurs, the MOS load switch is directly disconnected. If there is no phase loss, the voltage of phase B of the relay is continuously sampled. If a phase loss occurs, the MOS load switch is directly disconnected. If there is no phase loss, the voltage of phase C of the relay is continuously sampled. If a phase loss occurs, the MOS load switch is directly disconnected. If there is no phase loss, the relay returns to continue detecting phase A, and the protection monitoring relay is cycled in this way.

[0032] The present application discloses a phase-loss protection circuit structure based on voltage detection, which uses a low-cost optocoupler 6 for isolation and monitors the voltage at the three-phase output terminals of a three-phase relay in real time. Once a phase voltage signal is found to be missing, it can be quickly determined as a phase loss. When a phase loss is detected, the control module 2 will start protection measures, namely, disconnect the relay, turn off the power supply, and send out a warning signal to avoid damage to the equipment. The structure has the advantages of high detection accuracy, good protection effect, low cost, and strong stability. By quickly detecting the power supply voltage at the rear end of the relay, the phase loss fault can be detected in time to avoid damage to the equipment due to the phase loss. The control module 2 will immediately stop the equipment from running when a phase loss fault is detected, avoiding the potential safety hazards caused by the equipment continuing to run in a phase loss state.

[0033] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A phase loss protection circuit structure based on voltage detection, characterized in that: It includes a voltage detection module and a control module; The voltage detection module is connected to the control module; The voltage detection module detects the power supply voltage through the phase detection unit, converts it into an electronic signal and transmits it to the control module for processing; The control module receives the signal from the voltage detection module and controls the operation and shutdown of the device according to the signal.

2. A phase loss protection circuit structure based on voltage detection as claimed in claim 1, characterized in that: The phase detection unit is controlled and detected by a phase loss detection circuit.

3. A phase loss protection circuit structure based on voltage detection as claimed in claim 2, characterized in that: The phase-loss detection circuit is also connected to an alarm device; the alarm device performs corresponding feedback according to the signal given by the phase-loss detection circuit.

4. A phase loss protection circuit structure based on voltage detection as claimed in claim 3, characterized in that: The phase loss detection circuit includes a photocoupler; the photocoupler is provided with four pins, namely a first pin, a second pin, a third pin and a fourth pin; the first pin is connected in series with a first diode; the second pin is connected in series with a second diode, a first resistor, a second resistor, a third resistor, a fourth resistor and a fifth resistor in sequence; the third pin is directly grounded; the fourth pin is connected in series with a sixth resistor.

5. A phase loss protection circuit structure based on voltage detection as claimed in claim 4, characterized in that: A third diode and a seventh resistor are also arranged in parallel between the first pin and the second pin.

6. A phase loss protection circuit structure based on voltage detection as claimed in claim 5, characterized in that: The first pin, the second pin and the fourth pin of the photoelectric coupler are respectively used to monitor the three-phase output terminal voltage of the three-phase relay in real time.

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