CN109709374A - A kind of residual voltage detection circuit - Google Patents
A kind of residual voltage detection circuit Download PDFInfo
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- CN109709374A CN109709374A CN201910053783.2A CN201910053783A CN109709374A CN 109709374 A CN109709374 A CN 109709374A CN 201910053783 A CN201910053783 A CN 201910053783A CN 109709374 A CN109709374 A CN 109709374A
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- triode
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- voltage detection
- detection circuit
- residual voltage
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Abstract
The invention discloses a kind of residual voltage detection circuits being connected with distribution terminal, including energy-storage units and magnetic latching relay；In the state of distribution terminal power loss, energy-storage units can provide the actuation of closing coil electric energy, closure signal of the residual pressure signal output module in response to closing coil, the switch being closed in residual pressure signal output module, and export residual voltage detection signal.The residual voltage detection circuit can be detected residual pressure signal without terminal electrification.
Description
Technical field
The invention belongs to distribution line residual voltage detection field more particularly to a kind of residual voltage detection circuits.
Background technique
When occurring permanent fault point in distribution line, distribution terminal responds immediately to be opened on control breaker or column
Trip protection is closed, and circuit re-switching starts after a certain period of time, if coinciding with failure, protective device is by Accelerated trip.Performance
Feature out is exactly the false voltage cycle that will appear several periods, is disappeared immediately, referred to as residual voltage.After distribution terminal separating brake
It answers in real-time monitoring route whether there is or not residual pressure signal, if occurring being latched immediately, keeps gate-dividing state.
Existing residual voltage detection circuit could must effectively be detected in distribution terminal electriferous state, though circuit is simple, when matching
When electric terminals power loss, residual voltage detection circuit cannot work on.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of residual voltage detection circuit, which is without terminal electrification
Detectable residual pressure signal.
To solve the above problems, the technical solution of the present invention is as follows:
A kind of residual voltage detection circuit, is connected with distribution terminal, including energy-storage units and magnetic latching relay；
The magnetic latching relay includes closing coil and residual pressure signal output module, the residual pressure signal output module
In response to the closure signal of the closing coil, the switch being closed in the residual pressure signal output module, and export residual voltage detection
Signal；
The energy-storage units are connected with the distribution terminal, in the state of residual voltage detection circuit work, the storage
Energy unit stores the electricity that the distribution terminal provides, and in the state of the distribution terminal power loss, the energy-storage units are to institute
The actuation for stating closing coil provides electric energy.
The embodiment provided according to the present invention, the magnetic latching relay further include reset circuit, are detected in the residual voltage
In the state that circuit is powered on for the first time, the reset circuit detects the interference signal of the magnetic latching relay output, resets
Eliminate the interference signal.
The embodiment provided according to the present invention, the reset circuit include third transistor, photoelectrical coupler and reset
Coil；
The photoelectrical coupler is equipped with light emitting diode and light receiving unit, the cathode of the light emitting diode and described the
The collector of three triodes is electrically connected, the positive external power supply of the light emitting diode；
The resetting coil is electrically connected with the output end of the light receiving unit；
The reset circuit detects the interference signal, and the third transistor is connected, the LEDs ON,
To make the light receiving unit be connected, the resetting coil, which resets, eliminates the interference signal, disconnects the residual pressure signal output
Switch in module.
The embodiment provided according to the present invention, the residual voltage detection circuit further include combined floodgate driving circuit, the combined floodgate driving
Circuit includes the first voltage-stabiliser tube and the second triode；
The collector of second triode is electrically connected with the closing coil；
The cathode of first voltage-stabiliser tube is electrically connected with the ground level of second triode, the anode of first voltage-stabiliser tube
It is electrically connected with the emitting stage of second triode；
In the state of residual voltage detection circuit work, the residual pressure signal passes through first voltage-stabiliser tube, and in institute
It states and generates voltage difference between the base stage of the second triode and the emitting stage of second triode, second triode ON,
The closing coil conducting.
The embodiment provided according to the present invention, which further includes breaking circuit, and the breaking circuit includes
Second capacitor, the second voltage-stabiliser tube and the first triode；
The collector of first triode is electrically connected with the base stage of second triode, the base of first triode
Pole is electrically connected with the cathode of second voltage-stabiliser tube, the anode electricity of the emitting stage of first triode and second voltage-stabiliser tube
Connection；
The anode of second capacitor is electrically connected with the cathode of second voltage-stabiliser tube, the cathode of second capacitor and institute
State the anode electrical connection of the second voltage-stabiliser tube；
In the state of second capacitor charging, first triode ends, and second triode ON is described
Residual pressure signal output module exports the residual voltage and detects signal；And
In the state of second capacitor charging saturation, first triode ON, the second triode cut-off,
Disconnect the switch in the residual pressure signal output module.
The embodiment provided according to the present invention, the energy-storage units are first capacitors, the anode of the first capacitor and institute
State the anode electrical connection of the rectification circuit in residual voltage detection circuit, the cathode of the cathode of the first capacitor and the rectification circuit
Electrical connection.
The present invention due to using the technology described above, makes it have the following advantages that and actively imitate compared with prior art
Fruit:
1) energy-storage units in one embodiment of the invention are connected with distribution terminal, can storing electricity, in distribution terminal
Also electricity can be provided for the actuation of closing coil when power loss, the residual pressure signal output module in magnetic latching relay is in response to closing a floodgate
The closure signal of coil, the switch being closed in residual pressure signal output module, and export residual voltage detection signal.The residual voltage detection circuit
It can be detected residual pressure signal without terminal electrification.
2) reset circuit in one embodiment of the invention detects magnetic latching relay when the detection circuit powers on for the first time
The interference signal of output, and interference signal is resetted and is eliminated.It can be avoided the detection circuit and interference signal be mistaken for residual voltage letter
Number.
3) in one embodiment of the invention in the state of the second capacitor charging, the first triode base voltage is second
Close to zero potential during capacitor charging, off state is kept, when the second capacitor charging saturation, the base voltage of the first triode
The blanking voltage of the second voltage-stabiliser tube, the first triode ON are risen to, the second triode disconnects residual voltage letter because ground level decompression is ended
Switch in number output module.The closing coil of magnetic latching relay can be prevented to be chronically at live line work state.
Detailed description of the invention
Fig. 1 is a kind of schematic diagram of residual voltage detection circuit of the invention；
Fig. 2 is the schematic diagram of the reset circuit in one embodiment of the invention.
Specific embodiment
A kind of residual voltage detection circuit proposed by the present invention is made further specifically below in conjunction with the drawings and specific embodiments
It is bright.According to following explanation and claims, advantages and features of the invention will be become apparent from.
Referring to Fig. 1, a kind of residual voltage detection circuit is connected with distribution terminal, including energy-storage units and magnetic latching relay
RELAY1；Magnetic latching relay RELAY1 includes closing coil and residual pressure signal output module, and residual pressure signal output module is rung
Should be in the closure signal of closing coil, the switch being closed in residual pressure signal output module, and export residual voltage detection signal, energy storage list
Member is connected with distribution terminal, and in the state of the work of residual voltage detection circuit, energy-storage units store the electricity that distribution terminal provides,
In the state of distribution terminal power loss, energy-storage units provide electric energy to the actuation of closing coil.Due to the time of circuit output residual voltage
Very short, in the case where distribution terminal power loss, the energy that energy-storage units provide need to only meet the time of residual voltage output, therefore,
Energy-storage units use first capacitor C1 in the present embodiment.The anode and the diode rectification of the residual voltage detection circuit of first capacitor C1
The anode electrical connection of bridge BR1, the cathode of first capacitor C1 are electrically connected with the cathode of diode rectifier bridge BR1.
It is appreciated that the present embodiment in energy-storage units be connected with distribution terminal, can storing electricity, distribution terminal mistake
Electricity can be also provided when electric for the actuation of closing coil, the residual pressure signal output module in magnetic latching relay RELAY1 in response to
The closure signal of closing coil, the switch being closed in residual pressure signal output module, and export residual voltage detection signal.Residual voltage detection
Circuit can be detected residual pressure signal without terminal electrification.
Due to for the first time normally upper electricity operation when magnetic latching relay RELAY1 closing coil can also act, at this time magnetic keep after
Electric appliance RELAY1 output end has a non-residual pressure signal and keeps, and herein we term it interference signal, needs interference signal
It resets and eliminates, avoid residual voltage detection circuit that interference signal is mistaken for residual pressure signal.It therefore, is the present embodiment referring to Fig. 2, Fig. 2
In reset circuit schematic diagram, reset circuit includes third transistor V1, photoelectrical coupler OP1 and resetting coil；Photoelectricity
Coupler is equipped with light emitting diode and light receiving unit, and the collector of the cathode and third transistor V1 of light emitting diode is electrically connected
It connects, the positive external power supply of light emitting diode, resetting coil is electrically connected with the output end of light receiving unit, reset circuit detection interference
Third transistor V1 is connected in signal, LEDs ON, so that light receiving unit be made to be connected, resetting coil, which resets to eliminate, to be done
Signal is disturbed, the switch in residual pressure signal output module is disconnected.Preferably, the light receiving unit in the present embodiment uses photosensitive semiconductor
Pipe, certainly, in other embodiments, light receiving unit uses photo resistance, also belongs to protection scope of the present invention.
Reset circuit in the present embodiment detects the interference that magnetic latching relay exports when the detection circuit powers on for the first time
Signal, and interference signal is resetted and is eliminated.It can be avoided the detection circuit and interference signal be mistaken for residual pressure signal.
Further, which further includes combined floodgate driving circuit and breaking circuit, wherein close a floodgate driving electricity
Road includes second resistance R2,3rd resistor R4, the first voltage-stabiliser tube ZD1 and the second triode Q2；The current collection of second triode Q2
Pole is electrically connected with closing coil, and the cathode of the first voltage-stabiliser tube ZD1 is electrically connected with the ground level of the second triode Q2, the first voltage-stabiliser tube
The anode of ZD1 is electrically connected with the emitting stage of the second triode Q2, and the first end of second resistance R2 is electrically connected with closing coil, and second
The second end of resistance R2 is electrically connected with the base stage of the second triode Q2, the base of the first end of 3rd resistor R4 and the second triode Q2
Pole electrical connection, the second end of 3rd resistor R4 is electrically connected with the anode of the first voltage-stabiliser tube ZD1, in the shape of residual voltage detection circuit work
Under state, residual pressure signal passes through the first voltage-stabiliser tube ZD1, and the emitting stage of the base stage of the second triode Q2 and the second triode Q2 it
Between generate voltage difference, the second triode Q2 conducting, closing coil conducting.
Wherein, the base stage that the first voltage-stabiliser tube ZD1 can live in the second triode Q2 with clamper prevents overtension from damaging the two or three
Pole pipe Q2, second resistance R2 and 3rd resistor R4 can suitably delay the turn-on time of the second triode Q2, to guarantee to work as circuit
In when having residual pressure signal, first capacitor C1 can fully absorb energy, to enable first capacitor C1 in distribution terminal power loss
In the case where, the closing coil in magnetic latching relay RELAY1 is connected, exports residual pressure signal.
Breaking circuit includes first resistor R1, the second capacitor C2, the second voltage-stabiliser tube ZD2 and the first triode Q1；First
The first end of resistance R1 is electrically connected with the anode of first capacitor C1, the anode electricity of the second end of first resistor R1 and the second capacitor C2
Connection, the collector of the first triode Q1 are electrically connected with the base stage of the second triode Q2, the base stage and second of the first triode Q1
The cathode of voltage-stabiliser tube ZD2 is electrically connected, and the emitting stage of the first triode Q1 is electrically connected with the anode of the second voltage-stabiliser tube ZD2, the second electricity
The anode for holding C2 is electrically connected with the cathode of the second voltage-stabiliser tube ZD2, the anode electricity of the cathode of the second capacitor C2 and the second voltage-stabiliser tube ZD2
Connection, in the state that first resistor R1 and the second capacitor C2 charges, the first triode Q1 cut-off, the second triode Q2 conducting,
The residual voltage that residual pressure signal output module exports detects signal, and, in the state of first resistor R1 and the second capacitor C2 charging saturation
Under, the first triode Q1 conducting, the second triode Q2 cut-off disconnects the switch in residual pressure signal output module.
When the detection circuit normally powers on, if shutdown measure is not taken to the second triode Q2, then closing coil
It will be chronically at the working condition of electrification, and have residual pressure signal output always, if things go on like this magnetic latching relay RELAY1 can
Cause thermal damage can be crossed.In the present embodiment the second capacitor C2 charging in the state of, the base voltage of the first triode Q1 is second
Close to zero potential during capacitor C2 charging, off state is kept, when the second capacitor C2, which charges, to be saturated, the base of the first triode Q1
Step voltage rises to the blanking voltage of the second voltage-stabiliser tube ZD2, the first triode Q1 conducting, and the second triode Q2 is cut because of ground level decompression
Only, the switch in residual pressure signal output module is disconnected.The closing coil of magnetic latching relay RELAY1 can be prevented to be chronically at
Live line work state.
Residual voltage detection circuit further includes linear transformer T1, and the winding no-load voltage ratio of linear transformer T1 can be according to practical residual voltage
Trigger voltage flexible design.Power consumption can according to the computing the resistor value of second resistance R2 and 3rd resistor R4 in circuit,
Wherein, UdcCalculation method are as follows:
Wherein, UdcIndicate the input voltage of residual voltage detection circuit,The bundle number ratio of primary side and secondary side.
Under normal operation, it is assumed that the winding no-load voltage ratio N2/N1 of linear transformer T1 is 1/2, then UdcFor 156V, second is separately assumed
Resistance R2 and 3rd resistor R4 is 75k Ω, then the power consumption P being calculated is 1.04mW, and existing residual voltage detection circuit function
For consumption generally in tens mW, compared to existing residual voltage detection circuit, the residual voltage detection circuit in the present embodiment is low in energy consumption, will not be right
System causes any adverse effect, and in addition trigger voltage can set any definite value according to demand.
Embodiments of the present invention are explained in detail above in conjunction with attached drawing, but the present invention is not limited to above-mentioned implementations
Mode.Even if to the present invention, various changes can be made, if these variations belong to the model of the claims in the present invention and its equivalent technologies
Within enclosing, then still fall within the protection scope of the present invention.
Claims (6)
1. a kind of residual voltage detection circuit, is connected with distribution terminal, which is characterized in that keep relay including energy-storage units and magnetic
Device；
The magnetic latching relay includes closing coil and residual pressure signal output module, the residual pressure signal output module response
In the closure signal of the closing coil, the switch being closed in the residual pressure signal output module, and export residual voltage detection signal；
The energy-storage units are connected with the distribution terminal, in the state of residual voltage detection circuit work, the energy storage list
Member stores the electricity that the distribution terminal provides, and in the state of the distribution terminal power loss, the energy-storage units are to the conjunction
The actuation of brake cable circle provides electric energy.
2. residual voltage detection circuit as described in claim 1, which is characterized in that the magnetic latching relay further includes resetting electricity
Road, in the state that the residual voltage detection circuit is powered on for the first time, it is defeated that the reset circuit detects the magnetic latching relay
Interference signal out resets and eliminates the interference signal.
3. residual voltage detection circuit as claimed in claim 2, which is characterized in that the reset circuit includes third transistor, light
Electric coupler and resetting coil；
The photoelectrical coupler is equipped with light emitting diode and light receiving unit, the cathode of the light emitting diode and the described 3rd 3
The collector of pole pipe is electrically connected, the positive external power supply of the light emitting diode；
The resetting coil is electrically connected with the output end of the light receiving unit；
The reset circuit detects the interference signal, and the third transistor is connected, the LEDs ON, thus
The light receiving unit is connected, the resetting coil, which resets, eliminates the interference signal, disconnects the residual pressure signal output module
In switch.
4. residual voltage detection circuit as described in claim 1, which is characterized in that further include combined floodgate driving circuit, the combined floodgate drives
Dynamic circuit includes the first voltage-stabiliser tube and the second triode；
The collector of second triode is electrically connected with the closing coil；
The cathode of first voltage-stabiliser tube is electrically connected with the ground level of second triode, the anode of first voltage-stabiliser tube and institute
State the emitting stage electrical connection of the second triode；
In the state of residual voltage detection circuit work, the residual pressure signal passes through first voltage-stabiliser tube, and described the
Voltage difference is generated between the base stage of two triodes and the emitting stage of second triode, second triode ON is described
Closing coil conducting.
5. residual voltage detection circuit as claimed in claim 4, which is characterized in that it further include breaking circuit, the breaking circuit packet
Include the second capacitor, the second voltage-stabiliser tube and the first triode；
The collector of first triode is electrically connected with the base stage of second triode, the base stage of first triode with
The cathode of second voltage-stabiliser tube is electrically connected, and the emitting stage of first triode and the anode of second voltage-stabiliser tube are electrically connected
It connects；
The anode of second capacitor is electrically connected with the cathode of second voltage-stabiliser tube, the cathode of second capacitor and described the
The anode electrical connection of two voltage-stabiliser tubes；
In the state of second capacitor charging, the first triode cut-off, second triode ON, the residual voltage
Signal output module exports the residual voltage and detects signal；And
In the state of second capacitor charging saturation, first triode ON, the second triode cut-off is disconnected
Switch in the residual pressure signal output module.
6. residual voltage detection circuit as described in claim 1, which is characterized in that the energy-storage units are first capacitors, described
The anode of one capacitor is electrically connected with the anode of the rectification circuit in the residual voltage detection circuit, the cathode of the first capacitor and institute
State the cathode electrical connection of rectification circuit.
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| CN201910053783.2A CN109709374B (en) | 2019-01-21 | 2019-01-21 | Residual voltage detection circuit |
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| CN201910053783.2A CN109709374B (en) | 2019-01-21 | 2019-01-21 | Residual voltage detection circuit |
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| CN109709374B CN109709374B (en) | 2021-03-16 |
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Cited By (4)
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| CN110635459A (en) * | 2019-10-17 | 2019-12-31 | 广西电网有限责任公司南宁供电局 | Double-path check residual voltage locking method and circuit |
| CN111983297A (en) * | 2020-08-21 | 2020-11-24 | 重庆新世杰电气股份有限公司 | Instantaneous residual voltage detection method, device and equipment and residual voltage recording assembly |
| CN115207883A (en) * | 2022-06-23 | 2022-10-18 | 南京市嘉隆电气科技股份有限公司 | Method for realizing residual voltage detection |
| CN115201548A (en) * | 2022-09-14 | 2022-10-18 | 石家庄科林电气股份有限公司 | Residual voltage detection recording device and method for power distribution terminal |
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