CN206619551U - Extend the circuit of relay life under a kind of AC network - Google Patents
Extend the circuit of relay life under a kind of AC network Download PDFInfo
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- CN206619551U CN206619551U CN201720255154.4U CN201720255154U CN206619551U CN 206619551 U CN206619551 U CN 206619551U CN 201720255154 U CN201720255154 U CN 201720255154U CN 206619551 U CN206619551 U CN 206619551U
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Abstract
Extend the circuit of relay life, including mains frequency Acquisition Circuit, MCU and relay drive circuit under a kind of AC network, it is characterised in that：The output end of mains frequency Acquisition Circuit and MCU input are connected, and the input of relay drive circuit and MCU output end are connected, and the input of mains frequency Acquisition Circuit is exchange electrical input.The improvement that the utility model passes through said structure, ac grid voltage is converted into low and high level using mains frequency Acquisition Circuit, the low and high level is read by MCU input port and determines mains frequency, calculate the zero crossing of AC network next time, when needing to be turned on and off relay in the point, MCU determines that needs can be calculated after the time difference is turned on and off relay in sometime point, relay contact is set to reach no-voltage point adhesive or release in closure or release moment, contact arc-suppression is realized, the purpose of extension relay life is reached.
Description
Technical field
The utility model is related to the circuit for extending relay life under a kind of AC network.
Background technology
In the intelligent control technologies such as smart home, mobile household electrical appliance, one of control of most critical is exactly to dissimilarity
Matter loads (such as capacitive, inductive load) and control is cut-off in different capacity load (such as high-power, low-power load).Due to capacitive
The moment resistance value of the incandescent lamp even load of load or cold conditions on startup is very low, therefore the wink connected in control load
Between, power supply can produce the phenomenon of near short circuit, even 100 times of 10 when the dash current of its moment is normal work times, this
If high current can produce very big heat by the contact of relay and directly burn out contact, relay contact adhesion is caused, is contracted
The life-span of short relay.So generally extending the life-span of relay to reduce dash current by the way of Super-zero control.
However, current relay zero-crossing control circuit exists mostly, complicated, cost is higher, volume is larger, relay
Device service life is not grown and less reliable defect, it is difficult to meet the high use requirement of user.Therefore, it is necessary to further change
Enter.
Utility model content
The purpose of this utility model aim to provide low a kind of simple and reasonable, excellent performance, manufacturing cost, easy production,
Easily extend the circuit of relay life under realization, safe and reliable and service life length AC network, to overcome in the prior art
Weak point.
Extend the circuit of relay life, including mains frequency collection electricity under a kind of AC network designed by this purpose
Road, MCU and relay drive circuit, it is characterised in that：The output end of mains frequency Acquisition Circuit and MCU input are connected,
The input of relay drive circuit and MCU output end are connected, and the input of mains frequency Acquisition Circuit inputs for alternating current
End.
The mains frequency Acquisition Circuit includes R9 resistance, D10 diodes, U3 optocouplers, D11 diodes, R8 resistance, R10
Resistance and C6 electric capacity；Wherein, R9 resistance one end is connected with L lines, and the other end is connected with D10 diodes one end, and D10 diodes are another
Hold first end respectively with D11 diodes one end, U3 optocouplers primary circuit to be connected, the D11 diodes other end respectively with U3 optocouplers
Second end of primary circuit, the connection of N lines, the 3rd end of U3 optocouplers primary circuit are connected with ground wire, and the of U3 optocouplers primary circuit
Four ends are connected with R8 resistance one end, R10 resistance one end respectively, and the R8 resistance other end is connected with 5V power supplys, the R10 resistance other end point
Input not with C6 electric capacity one end, MCU is connected, and the C6 electric capacity other ends are connected with ground wire.
The mains frequency Acquisition Circuit include R9 ' resistance, D11 ' diodes, C4 ' electric capacity, Q2 ' triodes, C6 ' electric capacity,
R8 ' resistance and R10 ' resistance；Wherein, R9 ' resistance one end and L ' lines are connected, and the other end is electric with D11 ' diodes one end, C4 ' respectively
Hold one end, Q2 ' triodes first end connection, D11 ' the diodes other end respectively with N ' lines, C4 ' the electric capacity other end, Q2 ' triodes
Second end, ground wire, the connection of C6 ' electric capacity one end, the end of Q2 ' triodes the 3rd connect with R8 ' resistance one end, R10 ' resistance one end respectively
Connect, R8 ' the resistance other end is connected with+5V power supplys, input, the C6 electric capacity other end of R10 ' the resistance other end respectively with MCU connect
Connect.
The relay drive circuit includes R18 resistance, Q2 triodes, D17 diodes, ZD2 voltage-stabiliser tubes and RY2 relays
Device；Wherein, R18 resistance one end and MCU output end connection, the other end is connected with Q2 triode first ends, Q2 triodes second
End is connected with D17 diodes one end, RY2 relays one end respectively, and the D17 diodes other end is connected with ZD2 voltage-stabiliser tubes one end,
ZD2 voltage-stabiliser tubes other end difference 12V power supplys, the connection of the RY2 relays other end.
Also include the anti-deadlock circuits of MCU, the anti-deadlock circuits of the MCU include R25 resistance, C8 electric capacity, R24 resistance, the poles of Q7 tri-
Pipe, R28 resistance, EC8 patch capacitors, R29 resistance, R31 resistance and Q8 triodes；Wherein, R25 resistance one end and MCU output
End connection, the other end is connected with C8 electric capacity one end, and the C8 electric capacity other end connects with R24 resistance one end, Q7 triodes first end respectively
Connect, R24 resistance other end difference 5V power supplys, the connection of the end of Q7 triodes second, the end of Q7 triodes the 3rd connects with R28 resistance one end
Connect, the R28 resistance other end is connected with EC8 patch capacitors positive pole, R29 resistance one end respectively, EC8 patch capacitors negative pole respectively with
R31 resistance one end, Q8 triodes first end, ground wire connection, the R29 resistance other end respectively with the R31 resistance other end, Q8 triodes
Second end is connected, the end of Q8 triodes the 3rd and Q2 triode three-terminal links.
The utility model is by the improvement of said structure, using mains frequency Acquisition Circuit by the conversion of ac grid voltage
For low and high level, the low and high level is read by MCU input port and determines mains frequency, calculate AC network next time
Zero crossing, when needing to be turned on and off relay in the point, MCU determines that needs can be calculated after the time difference to be opened in sometime point
Relay is opened or closed, relay contact is reached no-voltage point adhesive or release in closure or release moment, realizes that contact disappears
Arc, reaches the purpose of extension relay life.
It has advantages below：
(1) acted by accurate no-voltage point, it is to avoid the high temperature consumption of contact arc discharge, relay life can be extended to 6
More than times.
(2) circuit design is simple, and software processing gets up simple and convenient, and clear logic cleverly passes through software and hardware combining
Mode is realized.
(3) circuit is easy-to-understand, can not be designed person well and grasp and be applied in actual design.
In terms of comprehensive, its simple and reasonable, excellent performance, manufacturing cost it is low, it is easy production, easily realize, it is safe and reliable and
The features such as service life is long, it is practical.
Brief description of the drawings
Fig. 1 is the way circuit schematic diagram of the utility model first embodiment.
Fig. 2 is the mains frequency Acquisition Circuit schematic diagram of the utility model first embodiment.
Fig. 3 is the relay drive circuit schematic diagram of the utility model first embodiment.
Fig. 4 is the anti-deadlock circuit theory diagrams of MCU of the utility model first embodiment.
Mains frequency Acquisition Circuit waveform analyses and software measurement mains frequency of the Fig. 5 for the utility model first embodiment
Schematic diagram.
Fig. 6, Fig. 7 are the software control relay schematic diagram of the utility model first embodiment.
Fig. 8 is the mains frequency Acquisition Circuit schematic diagram of the utility model second embodiment.
Embodiment
Below in conjunction with the accompanying drawings and embodiment is further described to the utility model.
First embodiment
Referring to Fig. 1-Fig. 7, extend the circuit of relay life, including mains frequency Acquisition Circuit, MCU under this AC network
And relay drive circuit, it is characterised in that：The output end of mains frequency Acquisition Circuit and MCU input are connected, relay
The input of drive circuit and MCU output end are connected, and the input of mains frequency Acquisition Circuit is exchange electrical input.
Frequency is measured by mains frequency Acquisition Circuit, realizes and opens and closes relay in power network no-voltage point, pass through spy
There is circuit to accelerate the release time of relay, reduce error, realize accurate no-voltage point break contact with reference to software algorithm, effectively
Avoid most arc loss.
Further speaking, as shown in Fig. 2 mains frequency Acquisition Circuit includes R9 resistance, D10 diodes, U3 optocouplers, D11
Diode, R8 resistance, R10 resistance and C6 electric capacity；Wherein, R9 resistance one end is connected with L lines, the other end and D10 diodes one end
Connection, first end of the D10 diodes other end respectively with D11 diodes one end, U3 optocouplers primary circuit is connected, D11 diodes
The other end the second end respectively with U3 optocouplers primary circuit, N lines are connected, and the 3rd end of U3 optocouplers primary circuit is connected with ground wire,
4th end of U3 optocouplers primary circuit is connected with R8 resistance one end, R10 resistance one end respectively, and the R8 resistance other end connects with 5V power supplys
Connect, input of the R10 resistance other end respectively with C6 electric capacity one end, MCU is connected, and the C6 electric capacity other ends are connected with ground wire.
Wherein, the purpose of mains frequency Acquisition Circuit is, by power network sine wave, half to be carried out by D10 diodes, D11 diodes
Ripple rectification, D10 diodes, D11 are used to protect optocoupler not to be reversed high-voltage breakdown, and by U3 light-coupled isolations and pull-up R8 electricity
Resistance, R10 resistance, are shaped as the square wave of low and high level, then export to MCU and measure after C6 capacitor filterings.
Further speaking, as shown in figure 3, relay drive circuit includes R18 resistance, Q2 triodes, D17 diodes, ZD2
Voltage-stabiliser tube and RY2 relays；Wherein, R18 resistance one end and MCU output end connection, the other end connects with Q2 triodes first end
Connect, the end of Q2 triodes second is connected with D17 diodes one end, RY2 relays one end respectively, and the D17 diodes other end and ZD2 are steady
Pressure pipe one end is connected, ZD2 voltage-stabiliser tubes other end difference 12V power supplys, the connection of the RY2 relays other end.
Wherein, relay drive circuit is powered using 12V, using D17 diodes, ZD2 voltage-stabiliser tubes and RY2 relay groups into
The continuous current circuit of one closure；When relay contact discharges, the electromotive force produced by the coil and iron core of RY2 relays, quilt
ZD2 voltage-stabiliser tubes are blocked in a higher electrical voltage point, and realization rapidly switches off relay, reduce what contact between relay discharged
Constant error.Wherein ZD2 voltage-stabiliser tubes play a part of quick release, accelerate to disconnect relay contact, relay when making volume production
Release time (such as 2.1ms-2.6ms) in 500us error range, R18 current-limiting resistances and Q2 triodes composition on-off circuit
Control relay.
Specifically, in addition to the anti-deadlock circuits of MCU, as shown in figure 4, the anti-deadlock circuits of the MCU include R25 resistance, C8
Electric capacity, R24 resistance, Q7 triodes, R28 resistance, EC8 patch capacitors, R29 resistance, R31 resistance and Q8 triodes；Wherein, R25
Resistance one end and MCU output end connection, the other end is connected with C8 electric capacity one end, the C8 electric capacity other end respectively with R24 resistance one
End, the connection of Q7 triodes first end, R24 resistance other end difference 5V power supplys, the connection of the end of Q7 triodes second, Q7 triodes the 3rd
End is connected with R28 resistance one end, and the R28 resistance other end is connected with EC8 patch capacitors positive pole, R29 resistance one end respectively, EC8 patches
Chip capacitor negative pole is connected with R31 resistance one end, Q8 triodes first end, ground wire respectively, and the R29 resistance other end is electric with R31 respectively
Hinder the other end, the connection of the end of Q8 triodes second, the end of Q8 triodes the 3rd and Q2 triode three-terminal links.
Wherein, the anti-deadlock circuits of MCU are to prevent MCU from crashing suddenly, it is impossible to disconnect relay and apply, the circuit by
MCU produces a pwm signal, by R25 resistance, after C8 electric capacity separated by direct communication, can effectively prevent from loading caused by MCU crashes
The possibility heated by mistake.5V power supplys charge after Q7 triodes, R28 resistance to EC8 patch capacitors, it is maintained necessarily
Voltage supplies Q8 triode ONs.The anti-deadlock circuits of the MCU are auxiliary circuit, for some occasions without particular/special requirement, this part
Circuit can be omitted, and directly can be directly grounded the Q2 triodes in relay drive circuit.
Extend under above-mentioned AC network on the circuit base of relay life, no-voltage is completed by software processing method
Point action, realizes contact arc extinguishing, so as to reach the purpose of extension relay life.
Specifically, for the relay of an open type, contact is in adhesive, and movable contact, which is accelerated, arrives stationary contact,
When reaching stationary contact, speed highest, naked eyes are difficult to differentiate, and the arc time that contact is produced is short, injure smaller to contact.Contact exists
During disconnection, movable contact slowly moves away from stationary contact from inactive state, now keeps small distance between contact for a long time, produce compared with
Big arc phenomenon, eliminates the electric arc, is greatly improved the life-span of relay.Power network can be obtained in real time using the software processing method
Frequency, is not influenceed measurement result by the fluctuation of mains frequency or voltage, and the mains frequency information collected can be used accurately
In the control of relay, realize that no-voltage point opens and closes relay.
Further speaking, as shown in figure 5, the state of this mouthful is read in MCU ports at regular intervals, the time interval
It is smaller more accurate generally in Microsecond grade, but the resource of MCU sequential can be taken, by taking 50 microseconds as an example, by reading continuous high electricity
Gentle low level number of times and, mains frequency can be known.
Specifically,
Software processing realizes that zero point pressure point is turned off：
Such as Fig. 6, will when first high level arrives, it is to be understood that also have a regular time to reach zero crossing
The regular time subtracts the release time intermediate value of relay, and (such as 2.1ms-2.6ms takes and 2.35) understood, then during by how many times
Between be spaced after can perform disconnect relay order, realize no-voltage point turn off relay, make contact avoid high-voltage arc discharge from being lost,
Extend the life-span number of times of relay.
It is exemplified below：
Port scan is carried out with 50us time intervals, scanned altogether to 202 continuous high level and 198 continuous bottom level,
It is (202+198) * 50us=20000us, i.e. 20ms to understand grid cycle；It can be seen from mains frequency Acquisition Circuit, for the first time
The time of high level to second of no-voltage point can learn according to Fig. 6, the time
T1=[(high level)/2+ (grid cycle)]/4
=[(202 high level)/2+ (grid cycle)]/4
=[(202 high level)/2+ (+198 low levels of 202 high level)]/4
=[3* (202 high level)+(198 high level)]/4
=[3* (202*50)+(198*50)]/4
=10050us
=10.05ms
T1 subtracts the release time intermediate value 2.35ms, i.e. 10.05ms-2.35ms=7.7ms, 7.7ms/50us=of relay
154 times.
I.e. when Continuous plus first time high level is to 154 times, the order of release relay is performed, as shown in Figure 7.
Software processing realizes the adhesive nearby of no-voltage point：
Because the adhesive of relay has certain error scope, cancelling pickup time intermediate value, (such as 4.5ms-6.5ms, takes
5.25ms), the method disconnected with reference to relay contact, finds the time point of relay adhesive, realizes the adhesive nearby of no-voltage point
Relay, reduces arcing loss, extends the life-span number of times of relay.
Second embodiment
Referring to Fig. 8, extend the circuit of relay life under this AC network, it is different from being in place of first embodiment：
Replacement circuit can be used to realize the function for mains frequency Acquisition Circuit, constitute one group of non-isolated mains frequency Acquisition Circuit.
Specifically, mains frequency Acquisition Circuit includes R9 ' resistance, D11 ' diodes, C4 ' electric capacity, Q2 ' triodes, C6 '
Electric capacity, R8 ' resistance and R10 ' resistance；Wherein, R9 ' resistance one end and L ' lines are connected, the other end respectively with D11 ' diodes one end,
C4 ' electric capacity one end, Q2 ' triodes first end connection, D11 ' the diodes other end respectively with N ' lines, C4 ' the electric capacity other end, Q2 '
The end of triode second, ground wire, C6 ' electric capacity one end connection, the end of Q2 ' triodes the 3rd respectively with R8 ' resistance one end, R10 ' resistance one
End connection, R8 ' the resistance other end is connected with+5V power supplys, and input, the C6 electric capacity of R10 ' the resistance other end respectively with MCU are another
End connection.
Other same first embodiments in not described part.
General principle of the present utility model, principal character and advantage of the present utility model has been shown and described above.Ability
The technical staff in domain should be recognized that the utility model is not restricted to the described embodiments, described in above-described embodiment and specification
Simply illustrate principle of the present utility model, the utility model also has on the premise of the utility model spirit and scope are not departed from
Various changes and modifications, these changes and improvements are both fallen within the range of claimed the utility model.The utility model requirement
Protection domain is defined by appended claims and its equivalent.
Claims (5)
1. extend the circuit of relay life under a kind of AC network, including mains frequency Acquisition Circuit, MCU and relay driving
Circuit, it is characterised in that：The output end of mains frequency Acquisition Circuit and MCU input are connected, relay drive circuit it is defeated
Enter end to be connected with MCU output end, the input of mains frequency Acquisition Circuit is exchange electrical input.
2. extend the circuit of relay life under AC network according to claim 1, it is characterised in that：The mains frequency
Acquisition Circuit includes R9 resistance, D10 diodes, U3 optocouplers, D11 diodes, R8 resistance, R10 resistance and C6 electric capacity；Wherein, R9
Resistance one end is connected with L lines, and the other end is connected with D10 diodes one end, the D10 diodes other end respectively with D11 diodes one
End, the first end connection of U3 optocouplers primary circuit, the D11 diodes other end the second end respectively with U3 optocouplers primary circuit, N lines
Connection, the 3rd end of U3 optocouplers primary circuit is connected with ground wire, the 4th end of U3 optocouplers primary circuit respectively with R8 resistance one end,
R10 resistance one end is connected, the R8 resistance other end is connected with 5V power supplys, the R10 resistance other end respectively with C6 electric capacity one end, MCU
Input is connected, and the C6 electric capacity other ends are connected with ground wire.
3. extend the circuit of relay life under AC network according to claim 1, it is characterised in that：The mains frequency
Acquisition Circuit includes R9 ' resistance, D11 ' diodes, C4 ' electric capacity, Q2 ' triodes, C6 ' electric capacity, R8 ' resistance and R10 ' resistance；Its
In, R9 ' resistance one end and L ' lines are connected, the other end respectively with D11 ' diodes one end, C4 ' electric capacity one end, Q2 ' triodes first
End connection, D11 ' the diodes other end respectively with N ' lines, C4 ' the electric capacity other end, the end of Q2 ' triodes second, ground wire, C6 ' electric capacity
One end is connected, and the end of Q2 ' triodes the 3rd is connected with R8 ' resistance one end, R10 ' resistance one end respectively, R8 ' the resistance other end and+5V
Power supply is connected, and input, the C6 electric capacity other ends of R10 ' the resistance other end respectively with MCU are connected.
4. extend the circuit of relay life under the AC network according to Claims 2 or 3, it is characterised in that：The relay
Device drive circuit includes R18 resistance, Q2 triodes, D17 diodes, ZD2 voltage-stabiliser tubes and RY2 relays；Wherein, R18 resistance one
End be connected with MCU output end, the other end is connected with Q2 triode first ends, the end of Q2 triodes second respectively with D17 diodes
One end, the connection of RY2 relays one end, the D17 diodes other end are connected with ZD2 voltage-stabiliser tubes one end, ZD2 voltage-stabiliser tubes other end difference
12V power supplys, the connection of the RY2 relays other end.
5. extend the circuit of relay life under AC network according to claim 4, it is characterised in that：It is also anti-including MCU
Deadlock circuit, the anti-deadlock circuits of the MCU include R25 resistance, C8 electric capacity, R24 resistance, Q7 triodes, R28 resistance, EC8 pasters electricity
Appearance, R29 resistance, R31 resistance and Q8 triodes；Wherein, R25 resistance one end and MCU output end connection, the other end and C8 electric capacity
One end is connected, and the C8 electric capacity other end is connected with R24 resistance one end, Q7 triode first ends respectively, R24 resistance other end difference 5V
Power supply, the connection of the end of Q7 triodes second, the end of Q7 triodes the 3rd is connected with R28 resistance one end, the R28 resistance other end respectively with
EC8 patch capacitors positive pole, R29 resistance one end connection, EC8 patch capacitors negative pole respectively with R31 resistance one end, Q8 triodes first
End, ground wire connection, the R29 resistance other end are connected with the R31 resistance other end, the end of Q8 triodes second respectively, Q8 triodes the 3rd
End and Q2 triode three-terminal links.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720255154.4U CN206619551U (en) | 2017-03-15 | 2017-03-15 | Extend the circuit of relay life under a kind of AC network |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720255154.4U CN206619551U (en) | 2017-03-15 | 2017-03-15 | Extend the circuit of relay life under a kind of AC network |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206619551U true CN206619551U (en) | 2017-11-07 |
Family
ID=60232815
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720255154.4U Active CN206619551U (en) | 2017-03-15 | 2017-03-15 | Extend the circuit of relay life under a kind of AC network |
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| Country | Link |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110379675A (en) * | 2019-07-09 | 2019-10-25 | 深圳鼎元智电科技有限公司 | Relay drive circuit and relay low power consumption method |
| CN111029214A (en) * | 2019-12-26 | 2020-04-17 | 中国电子科技集团公司第五十八研究所 | Low-side driving circuit of high-voltage relay |
-
2017
- 2017-03-15 CN CN201720255154.4U patent/CN206619551U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110379675A (en) * | 2019-07-09 | 2019-10-25 | 深圳鼎元智电科技有限公司 | Relay drive circuit and relay low power consumption method |
| CN111029214A (en) * | 2019-12-26 | 2020-04-17 | 中国电子科技集团公司第五十八研究所 | Low-side driving circuit of high-voltage relay |
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