CN212008740U - Power failure detection device - Google Patents
Power failure detection device Download PDFInfo
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- CN212008740U CN212008740U CN201922420000.8U CN201922420000U CN212008740U CN 212008740 U CN212008740 U CN 212008740U CN 201922420000 U CN201922420000 U CN 201922420000U CN 212008740 U CN212008740 U CN 212008740U
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Abstract
The utility model discloses a power failure detection device, which comprises a rectifier bridge, a direction limiting diode, an energy storage capacitor, a voltage reduction module, an optocoupler and a detector; the input end of the rectifier bridge is connected with the power supply, the output end of the rectifier bridge is connected with the input end of the voltage reduction module through the energy storage capacitor, and the output end of the voltage reduction module is connected with the working circuit and the detector; the energy storage capacitor is used for storing electric energy output by the rectifier bridge; the voltage reduction module is used for carrying out voltage reduction processing on the voltage output by the rectifier bridge and outputting the voltage to the working circuit and the detector; the direction limiting diode is arranged between the output end of the rectifier bridge and the energy storage capacitor and used for limiting the output direction of the power supply; the output end of the rectifier bridge is also connected with a detector through an optical coupler, and the detector is used for detecting a level signal output by the optical coupler. Adopt the utility model discloses, can simplify and fall the electric detection circuit structure to adopt energy storage capacitor to provide backup source in order to accomplish operations such as data storage for working circuit and detector after falling the electricity, reduce the loss.
Description
Technical Field
The utility model relates to a detection device especially relates to a power down detection device.
Background
A rectifier bridge: the rectifier bridge is formed by sealing a rectifier tube in a shell and is divided into a full bridge and a half bridge. The full bridge seals the four direction limiting diodes of the connected bridge rectification circuit together. The half-bridge seals one half of four direction limiting diodes in a bridge rectification mode, two half-bridges can form a bridge rectification circuit, and one half-bridge can also form a full-wave rectification circuit with a center tap of a transformer.
And the AC _ DC power supply module is used for converting high-voltage alternating current or direct current into constant direct current power supply.
The optical coupler, also called as a photoelectric isolator or a photoelectric coupler, emits light when an input end is electrified, and generates light current after a light receiver receives the light, and the light current flows out from an output end, so that 'electricity-light-electricity' conversion is realized. And a photoelectric coupler for coupling the input signal to the output end by using light as medium.
The existing power failure detection circuit is complex in structure, and loss is caused because data cannot be stored or other operations cannot be carried out in time after power failure.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the technical problem that will solve is in, simplify and fall the electric detection circuit structure to adopt energy storage capacitor to provide backup source in order to accomplish operations such as data storage for working circuit and detector after falling the electricity, reduce the loss.
In order to solve the technical problem, the utility model provides a power failure detection device, which comprises a rectifier bridge, a direction limiting diode, an energy storage capacitor, a voltage reduction module, an optocoupler and a detector; the input end of the rectifier bridge is connected with the power supply, the output end of the rectifier bridge is connected with the input end of the voltage reduction module through the energy storage capacitor, and the output end of the voltage reduction module is connected with the working circuit and the detector; the energy storage capacitor is used for storing electric energy output by the rectifier bridge; the voltage reduction module is used for carrying out voltage reduction processing on the voltage output by the rectifier bridge and outputting the voltage to the working circuit and the detector; the direction limiting diode is arranged between the output end of the rectifier bridge and the energy storage capacitor and used for limiting the output direction of the power supply; the output end of the rectifier bridge is also connected with a detector through an optical coupler, and the detector is used for detecting a level signal output by the optical coupler.
As an improvement of the above scheme, a power live wire is connected with a first input end of a rectifier bridge, a power zero line is connected with a second input end of the rectifier bridge, an anode output end of the rectifier bridge is connected with an input end of a direction limiting diode, an output end of the direction limiting diode is connected with a first input end of a voltage reduction module through an energy storage capacitor, an anode output end of the voltage reduction module is connected with an optocoupler, the optocoupler is connected with one end of a detector, the other end of the detector is connected with a cathode output end of the voltage reduction module, and the second input end of the voltage reduction module is connected with a cathode output end of the rectifier bridge through the; the positive output end of the rectifier bridge is further connected with the optocoupler, and the optocoupler is connected with the negative output end of the rectifier bridge.
As an improvement of the above scheme, the optocoupler comprises a light emitting diode and a phototriode; the positive output end of the voltage reduction module is connected with the emitting electrode of the phototriode, and the collecting electrode of the phototriode is connected with one end of the detector; the positive output end of the rectifier bridge is also connected with the input end of the light-emitting diode, and the output end of the light-emitting diode is connected with the negative output end of the rectifier bridge.
As an improvement of the scheme, the voltage reduction circuit further comprises a load resistor, wherein the anode output end of the voltage reduction module is connected with one end of the load resistor, and the cathode output end of the voltage reduction module is connected with the other end of the load resistor.
As an improvement of the scheme, the voltage reduction circuit further comprises a load filter capacitor, and the voltage reduction module is connected with the load resistor through the load filter capacitor.
As an improvement of the scheme, the LED lamp further comprises a light-emitting device voltage-dividing resistor group, wherein the rectifier bridge is connected with the light-emitting device voltage-dividing resistor group, and the light-emitting device voltage-dividing resistor group is connected with the light-emitting diode.
As an improvement of the scheme, the voltage reduction circuit further comprises a shunt resistor, wherein the anode output end of the voltage reduction module is connected with one end of the shunt resistor, and the other end of the shunt resistor is connected with an emitting electrode of the phototriode.
As the improvement of the scheme, the photoelectric detector further comprises a signal divider resistor, wherein the collector of the photoelectric triode is connected with one end of the signal divider resistor, and the other end of the signal divider resistor is connected with the detector.
As an improvement of the scheme, the device further comprises a signal filtering capacitor bank, and the signal divider resistor is connected with the detector through the signal filtering capacitor bank.
As the improvement of the scheme, the power supply further comprises a fuse, a power supply live wire is connected with one end of the fuse, and the other end of the fuse is connected with a first input end of the rectifier bridge.
Implement the utility model has the advantages that:
implement the utility model discloses fall electric detection device, simplify and fall electric detection circuit structure to adopt energy storage capacitor to provide backup source in order to accomplish operations such as data storage for working circuit and detector after falling the electricity, reduce the loss.
Specifically, during normal power supply, the power supply provides electric energy for the working circuit after passing through the rectifier bridge, the limiting diode, the energy storage capacitor and the voltage reduction module, and the electric energy is stored in the energy storage capacitor. Meanwhile, current flows to the optical coupler through the rectifier bridge, so that the optical coupler is conducted and generates induced current, the electric signal of the induced current is high level, and the high level electric signal is transmitted to the detector from the optical coupler. When the power is off, the energy storage capacitor is used as a backup power supply to release electric energy and provide the electric energy for the working circuit and the detector. Because the optical coupler is not conducted, an electric signal generated by the optical coupler is far lower than a high level. The detector starts to control the working circuit to perform data saving and other operations to reduce loss after detecting the low-level electric signal.
Drawings
Fig. 1 is a schematic structural diagram of a first embodiment of the power failure detection device of the present invention;
fig. 2 is a schematic structural diagram of a second embodiment of the power failure detection device of the present invention;
fig. 3 is the utility model discloses fall electric detection device third embodiment schematic structure.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings. It is only noted that the invention is intended to be limited to the specific forms set forth herein, including any reference to the drawings, as well as any other specific forms of embodiments of the invention.
Fig. 1 shows the utility model discloses power down detection device's first embodiment schematic structure, including rectifier bridge an, limit to diode b, energy storage electric capacity c, step-down module d, opto-coupler e and detector f. The input end of the rectifier bridge a is connected with the power supply, the output end of the rectifier bridge a is connected with the input end of the voltage reduction module d through the energy storage capacitor c, and the output end of the voltage reduction module d is connected with the working circuit and the detector f. The direction limiting diode b is arranged between the output end of the rectifier bridge a and the energy storage capacitor c. The output end of the rectifier bridge a is also connected with a detector f through an optical coupler e.
The rectifier bridge a is used for converting alternating current with periodically changing direction into current with constant direction. Preferably, the model of the rectifier bridge can adopt KBL 410.
The direction limiting diode b is used for limiting the direction of the current released by the energy storage capacitor c to enable the current to flow to the voltage reduction module d, and no part of the current flows to the optical coupler e from the direction from the rectifier bridge a to the optical coupler e. Otherwise, the electric energy supplied to the working circuit by the energy storage capacitor c is reduced, and the optocoupler e is switched on by mistake, so that the detector f receives a wrong electric signal. Preferably, the type of the direction limiting diode b can adopt RS 1M.
And the energy storage capacitor c is used for storing the electric energy output by the rectifier bridge and used as a backup power supply. The energy storage capacitor c is a capacitor with large capacity, so that enough power supply time is provided for the working circuit when power is down, and the working circuit can timely store data and the like. Preferably, the energy storage capacitor can adopt an electrolytic capacitor with the specification of (100 muF, 450V).
And the voltage reduction module d is used for carrying out voltage reduction processing on the voltage output by the rectifier bridge a and outputting the voltage to the working circuit and the detector f. It should be noted that the positive output end and the negative output end of the voltage-reducing module d may be used to connect to a working circuit, such as directly connecting to an electrical appliance such as a motor and an electric lamp, and may be specifically connected between the end d5 and the end d6 in fig. 1. Preferably, the voltage reduction module is an AC _ DC power supply module. The AC _ DC power supply module is used for converting high-voltage alternating current or direct current into constant direct current power supply and has the function of voltage reduction. The model of the AC-DC module can adopt LH 10-10B.
The detector f is used for detecting a level signal output by the optocoupler e, so that the power supply condition of the power supply is detected in real time. Preferably, the detector is a microcontroller. A Micro Control Unit (MCU) includes a large number of comparison circuits, which can perform comparison operations, i.e., comparing a received electrical signal as an input voltage with a reference voltage corresponding to a high-level electrical signal. When the input voltage is equal to the reference voltage, the output end of the comparison circuit outputs another high-level signal to represent '1' in the binary system, so that the received signal is determined to be a high-level electric signal, otherwise, the output end of the comparison circuit outputs a low-level signal to represent '0' in the binary system, so that the power-down condition is determined to occur. In addition, the microcontroller may perform other operations after detecting a power-down condition, such as saving data, driving other devices to safely shut down, and so forth. The model of the microcontroller can adopt AD 7705.
When the power supply is normal, the power supply provides electric energy for the working circuit after passing through the rectifier bridge a, the limiting diode b, the energy storage capacitor c and the voltage reduction module d, and the electric energy is stored in the energy storage capacitor c. Meanwhile, current flows to the optical coupler e through the rectifier bridge a, the optical coupler e is conducted, induced current is generated, an electric signal of the induced current is high level, and the high level electric signal is transmitted to the detector f from the optical coupler e. When the power is off, the energy storage capacitor c is used as a backup power supply to release electric energy and provide the electric energy for the working circuit and the detector f. Because the optical coupler e is not conducted, an electric signal generated by the optical coupler e is far lower than a high level. The detector f starts to control the operation circuit to perform data saving or the like to reduce the loss after detecting the low level electric signal.
Fig. 2 is a schematic structural diagram of a second embodiment of the power down detection apparatus of the present invention, which is an improvement of the first embodiment.
Furthermore, a power supply live wire h1 is connected with a first input end a1 of the rectifier bridge, a power supply null wire h2 is connected with a second input end a2 of the rectifier bridge, an anode output end a3 of the rectifier bridge is connected with an input end b1 of the direction limiting diode b, an output end b2 of the direction limiting diode is connected with a first input end d1 of the voltage reduction module d through an energy storage capacitor c, an anode output end d3 of the voltage reduction module is connected with an optical coupler e, the optical coupler e is connected with one end of the detector f, the other end of the detector is connected with a cathode output end d4 of the voltage reduction module d, and a second input end d2 of the voltage reduction module is connected with a cathode output end a4 of the rectifier bridge through an energy storage capacitor; the positive output end a3 of the rectifier bridge is further connected with an optocoupler e, and the optocoupler e is connected with the negative output end a4 of the rectifier bridge.
Further, the optocoupler e includes a light emitting diode e1 and a phototransistor e 2. The positive electrode output end d3 of the voltage reduction module is connected with the emitter e21 of the phototriode, and the collector e22 of the phototriode is connected with one end of the detector f; the anode output end a3 of the rectifier bridge is also connected with the input end e11 of the light-emitting diode, and the output end e12 of the light-emitting diode is connected with the cathode output end of the rectifier bridge.
The light emitting diode e1 is used for converting the electrical signal into an optical signal, and the optical signal is transmitted to the base of the phototriode e2, so that the phototriode is conducted, the optical signal emitted by the light emitting diode e1 is converted into the electrical signal, and the electrical signal is used for judging whether the power failure condition occurs or not. Preferably, the type of the optical coupler can adopt TLV-217-B.
When the power supply is normal, the power supply provides electric energy for the working circuit after passing through the rectifier bridge a, the limiting diode b, the energy storage capacitor c and the voltage reduction module d, and the electric energy is stored in the energy storage capacitor c. At the same time, the current also flows to the light emitting diode e1 through the rectifier bridge a, and makes the phototransistor e2 conductive. The electrical signal generated by the phototransistor e2 is high. The high level electrical signal is transmitted from the phototransistor e2 to the detector f, which receives the high level electrical signal and does not take any action.
When the power is off, the energy storage capacitor c is used as a backup power supply to release electric energy and provide the electric energy for the working circuit and the detector f. Meanwhile, since no current flows from the rectifier bridge a to the light emitting diode e1, the phototransistor e2 is not turned on, and the electrical signal generated by the phototransistor e2 by means of the electric energy discharged from the energy storage capacitor c is much lower than the high level. The detector f performs data saving or the like to reduce loss after detecting a low level electric signal.
Fig. 3 is a schematic structural diagram of a third embodiment of the power failure detection apparatus of the present invention, which is an improvement of the second embodiment, and the following describes the improvement of the third embodiment in detail.
Further, the voltage reduction module comprises a load resistor g, a positive electrode output end d3 of the voltage reduction module d is connected with one end of the load resistor g, and a negative electrode output end d4 of the voltage reduction module is connected with the other end of the load resistor g.
The load resistor g is used for simulating the whole circuit operation condition when the voltage reduction module d is connected with the working circuit, so that the debugging result of the power failure detection device is more accurate.
Furthermore, the voltage reduction module d is connected with the load resistor g through the load filter capacitor h.
The load filter capacitor h is used for filtering the current output by the voltage reduction module d, so that the current output to the load resistor g is smoother, the final size is constant, and the requirement of a working circuit simulated by the load resistor g on direct current is met. As shown in fig. 3, the voltage dropping module d is electrically connected to two load filter capacitors h, and the two load filter capacitors h are electrically connected to the load resistor g.
Further, the LED driving circuit further comprises a light-emitting device voltage-dividing resistor group i, the rectifier bridge a is connected with the light-emitting device voltage-dividing resistor group, and the light-emitting device voltage-dividing resistor group i is connected with the light-emitting diode e 1.
The light emitter voltage dividing resistor group i is used for performing voltage dividing processing on the voltage output by the rectifier bridge a and preventing the voltage output to the light emitting diode e1 from being too high. The light emitter voltage dividing resistor group i comprises four resistors, namely k1, k2, k3 and k 4. The user can increase or decrease the number of resistors in the light emitter voltage dividing resistor group i according to the requirement.
Further, the voltage-reducing circuit further comprises a shunt resistor j, wherein the positive electrode output end d3 of the voltage-reducing module d is connected with one end of the shunt resistor j, and the other end of the shunt resistor j is connected with the emitter g1 of the phototransistor e 2.
The shunt resistor j is used for shunting part of the current output by the voltage reduction module d to the phototransistor e2, so that the phototransistor e2 can output a high-level electric signal when being conducted, and can output a low-level electric signal when not being conducted.
Furthermore, the photoelectric detector further comprises a signal divider resistance k, wherein a collector g2 of the phototransistor is connected with one end of the signal divider resistance k, and the other end of the signal divider resistance k is connected with the detector f.
The signal dividing resistor k is used for dividing the voltage output by the phototransistor e 2. When the phototriode e2 is not conducted, the electric signal of the phototriode e2 is further pulled down, so that the detector f can obtain an electric signal which is obviously different from the high-level electric signal, and the detector f can conveniently judge the power failure condition. It should be noted that the voltage across the signal dividing resistor k is the voltage detected by the detector f.
Furthermore, the device also comprises a signal filtering capacitor bank l, and the signal voltage dividing resistor k is connected with the detector f through the signal filtering capacitor bank l.
The signal filter capacitor group l is used for filtering the current, so that the detector f obtains a smooth electric signal, signal noise is effectively reduced, and detection accuracy is improved.
Furthermore, the power supply further comprises a fuse m, a power supply live wire is connected with one end of the fuse m, and the other end of the fuse m is connected with the first input end a1 of the rectifier bridge.
The fuse m disconnects the power supply when the circuit is overloaded, so that the safety of all circuits is guaranteed.
The foregoing is a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many modifications and decorations can be made without departing from the principle of the invention, and these modifications and decorations are also regarded as the protection scope of the present invention.
Claims (10)
1. A power failure detection device is characterized by comprising a rectifier bridge, a direction limiting diode, an energy storage capacitor, a voltage reduction module, an optocoupler and a detector;
the input end of the rectifier bridge is connected with a power supply, the output end of the rectifier bridge is connected with the input end of the voltage reduction module through an energy storage capacitor, and the output end of the voltage reduction module is connected with the working circuit and the detector;
the energy storage capacitor is used for storing the electric energy output by the rectifier bridge;
the voltage reduction module is used for carrying out voltage reduction processing on the voltage output by the rectifier bridge and outputting the voltage to the working circuit and the detector;
the direction limiting diode is arranged between the output end of the rectifier bridge and the energy storage capacitor and used for limiting the output direction of the power supply;
the output end of the rectifier bridge is further connected with a detector through the optocoupler, and the detector is used for detecting a level signal output by the optocoupler.
2. The power failure detection device according to claim 1, wherein a live power line is connected to a first input end of the rectifier bridge, a neutral power line is connected to a second input end of the rectifier bridge, an anode output end of the rectifier bridge is connected to an input end of the direction limiting diode, an output end of the direction limiting diode is connected to the first input end of the voltage reduction module through the energy storage capacitor, an anode output end of the voltage reduction module is connected to the optocoupler, the optocoupler is connected to one end of the detector, the other end of the detector is connected to a cathode output end of the voltage reduction module, and the second input end of the voltage reduction module is connected to a cathode output end of the rectifier bridge through the energy storage capacitor;
the positive output end of the rectifier bridge is further connected with the optocoupler, and the optocoupler is connected with the negative output end of the rectifier bridge.
3. The power failure detection device according to claim 2, wherein the optocoupler includes a light emitting diode and a photo-transistor;
the positive electrode output end of the voltage reduction module is connected with the emitting electrode of the phototriode, and the collecting electrode of the phototriode is connected with one end of the detector;
the positive electrode output end of the rectifier bridge is further connected with the input end of the light-emitting diode, and the output end of the light-emitting diode is connected with the negative electrode output end of the rectifier bridge.
4. The power failure detection device according to claim 3, further comprising a load resistor, wherein the positive output terminal of the voltage-reducing module is connected to one end of the load resistor, and the negative output terminal of the voltage-reducing module is connected to the other end of the load resistor.
5. The power failure detection device according to claim 4, further comprising a load filter capacitor, wherein the voltage dropping module is connected to the load resistor through the load filter capacitor.
6. The power failure detection device according to claim 5, further comprising a set of light emitter voltage dividing resistors, wherein the rectifier bridge is connected to the set of light emitter voltage dividing resistors, and the set of light emitter voltage dividing resistors is connected to the light emitting diode.
7. The power failure detection device according to claim 6, further comprising a shunt resistor, wherein the positive output terminal of the voltage reduction module is connected to one end of the shunt resistor, and the other end of the shunt resistor is connected to the emitter of the phototransistor.
8. The power-down detection device according to claim 7, further comprising a signal divider resistor, wherein a collector of the photo-transistor is connected to one end of the signal divider resistor, and the other end of the signal divider resistor is connected to the detector.
9. The power down detection device of claim 8, further comprising a signal filter capacitor bank, wherein the signal divider resistor is connected to the detector through the signal filter capacitor bank.
10. The power loss detection device as claimed in claim 9, further comprising a fuse, wherein the power line is connected to one end of the fuse, and the other end of the fuse is connected to the first input terminal of the rectifier bridge.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201922420000.8U CN212008740U (en) | 2019-12-26 | 2019-12-26 | Power failure detection device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201922420000.8U CN212008740U (en) | 2019-12-26 | 2019-12-26 | Power failure detection device |
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| CN212008740U true CN212008740U (en) | 2020-11-24 |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113189536A (en) * | 2021-05-31 | 2021-07-30 | 宁波迦南智能电气股份有限公司 | Power failure detection method and circuit for intelligent meter |
| CN113606762A (en) * | 2021-07-07 | 2021-11-05 | 珠海格力电器股份有限公司 | Electric quantity data storage device, method, controller and multi-online system |
| CN113922655A (en) * | 2021-10-18 | 2022-01-11 | 无锡市欧瑞杰电子科技有限公司 | PWM chip starts and loses electric warning circuit and switching power supply |
| CN115932386A (en) * | 2023-03-09 | 2023-04-07 | 深圳龙电华鑫控股集团股份有限公司 | Electric energy metering circuit and electric energy metering device |
-
2019
- 2019-12-26 CN CN201922420000.8U patent/CN212008740U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113189536A (en) * | 2021-05-31 | 2021-07-30 | 宁波迦南智能电气股份有限公司 | Power failure detection method and circuit for intelligent meter |
| CN113606762A (en) * | 2021-07-07 | 2021-11-05 | 珠海格力电器股份有限公司 | Electric quantity data storage device, method, controller and multi-online system |
| CN113922655A (en) * | 2021-10-18 | 2022-01-11 | 无锡市欧瑞杰电子科技有限公司 | PWM chip starts and loses electric warning circuit and switching power supply |
| CN113922655B (en) * | 2021-10-18 | 2024-02-20 | 无锡市欧瑞杰电子科技有限公司 | PWM chip starting and power-off alarm circuit and switching power supply |
| CN115932386A (en) * | 2023-03-09 | 2023-04-07 | 深圳龙电华鑫控股集团股份有限公司 | Electric energy metering circuit and electric energy metering device |
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