CN209344750U - A kind of self-powered microcomputer protecting device of belt current tripping - Google Patents
A kind of self-powered microcomputer protecting device of belt current tripping Download PDFInfo
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- CN209344750U CN209344750U CN201920161420.6U CN201920161420U CN209344750U CN 209344750 U CN209344750 U CN 209344750U CN 201920161420 U CN201920161420 U CN 201920161420U CN 209344750 U CN209344750 U CN 209344750U
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- 230000004224 protection Effects 0.000 claims abstract description 69
- 238000005070 sampling Methods 0.000 claims abstract description 52
- 230000009471 action Effects 0.000 abstract description 6
- 238000001514 detection method Methods 0.000 abstract description 6
- 230000004069 differentiation Effects 0.000 abstract description 6
- 230000001681 protective effect Effects 0.000 description 11
- 230000005611 electricity Effects 0.000 description 8
- 230000001131 transforming effect Effects 0.000 description 7
- 230000007423 decrease Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
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- 230000009286 beneficial effect Effects 0.000 description 1
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- 239000004973 liquid crystal related substance Substances 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
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Abstract
The utility model relates to a kind of self-powered microcomputer protecting devices of belt current tripping; including CT sampling circuit; CT sampling circuit includes A phase CT sampling circuit; A phase CT sampling circuit include current transformer 2LHa, Current Transmit a and with the concatenated make and break contact JA2 of current transformer; A phase CT sampling circuit further includes A phase energy converter Ta and overcurrent tripping in parallel with make and break contact JA2 protection circuit, overcurrent tripping protection circuit include overcurrent release Y7 and with the concatenated make and break contact JA1 of overcurrent release Y7.When short circuit accident occurs for power supply system; A phase energy converter Ta acquires short circuit accident current energy; and it converts and powers to microcomputer protecting device; microcomputer protecting device is worked normally; detection and differentiation are made to accident; and starting protection action command, electric network fault point is cut off, avoids microcomputer protecting device because of shielding failure caused by external working power voltage is too low or power loss two.
Description
Technical field
The utility model relates to Microcomputer Protection technical fields, protect more particularly, to a kind of self-powered microcomputer of belt current tripping
Protection unit.
Background technique
In power system industry, 10KV and above transformer and distribution power station, supply load be greater than 400KVA capacity with
Protection, measurement and the control of upper high-tension transformation equipment are all realized using microcomputer protecting device.Its China National Grid is administrative
Be provided in the transformer equipment of 10KV switching station, 35KV and above special DC power supply panel (DC110V or
DC220V) as the working power of microcomputer protecting device and switchgear, but some 10KV middle and small scale distribution transformings, case become and
Looped network controller switching equipment, due to not making working power using DC power supply panel by the small limitation in place and investment reduction etc., but
It directlys adopt 10KV bus voltage transformer and is directly depressured to working power of the alternating current 220V as equipment.
Although economical convenient and practical using the equipment of ac working power supply occasion, the reliability of its power supply cannot be protected
At this moment card is such as powered or is used if the AC220V power loss or unstable, just influences whether the reliability of system protection equipment
Electric equipment breaks down, and electrical protection apparatus loses protective effect because working power is unstable, cannot timely and effective excision failure
Point, and then cause more to arrive upper level switch trip, expand power outage.
In actual use, following situations will cause the unstable of institute electricity consumption AC220V: 1., when 10KV buckling fuse failure
When, 3., transformer near point short circuit accident 2., system is when occurring the big accident of power supply of 10KV busbar short-circuit, outlet phase fault etc.,
When etc..The decline of system 10KV busbar voltage, PT secondary side spread of voltage (voltage phase shortage, power loss can be all caused in the case of these
Or line voltage decline), the working power of AC220V is unreliable, and voltage value drops to 50% sometimes and hereinafter, causesIt is micro-
The second protections such as machine protective device equipment shielding failure due to working power voltage is too low, cannot effectively and excision accident route,When supply voltage drop to 75% and it is following after, shunt tripping line packet can not effective action.
Conventional microcomputer protecting device is all to provide back work electricity to circuits such as device single-chip microcontrollers by extraneous working power
Source differentiates whether the electric current of acquisition is more than setting value, and when electric current transfinites, the movement of protective device exit relay is connected height and pressed off
The movement tripping of cabinet breaking coil is closed, is played a protective role.The premise of above-mentioned reliably working is that have a reliable and stable back work
Power supply, general electric system back work power supply are broadly divided into direct current 220V, direct current 110V and alternating current 220V, wherein DC220V,
DC110V working power be using special DC power supply panel provide, this power mode is reliable and stable, most of 10KV and with
Upper substation is all in this way.But small distribution transforming and case change, looped network controller switching equipment in some 10KV, due to by the small limit in place
System and investment reduction etc. do not make working power using DC power supply panel, but directly adopt 10KV bus voltage transformer and directly drop
It is pressed onto working power of the alternating current 220V as equipment.If the AC220V power loss or unstable, just influence whether that system is protected
Protect the reliability of equipment.Although an ac working power supply is economical convenient and practical, the reliability of its power supply cannot be guaranteed,
It will result in secondary voltage phase shortage, power loss or line voltage decline etc. when buckling fuse failure, especially big confession occurs for system
When electrification (when such as 10KV busbar short-circuit, outlet phase fault and near point short circuit accident), system 10KV bus electricity will result in
Drops, PT secondary side spread of voltage, the working power voltage value of AC220V drop to 50% sometimes and hereinafter, cause micro-
The second protections such as machine device equipment shielding failure due to working power is too low, cannot effective and excision accident route.
Utility model content
The technical problem to be solved by the utility model is to provide one kind can be avoided shielding failure, guarantees that power supply system is steady
It is qualitative, and reduce the self-powered microcomputer protecting device of the belt current tripping of the comprehensive project cost from distribution transforming user.
The utility model the technical scheme adopted is that a kind of belt current tripping self-powered microcomputer protecting device, including
CT sampling circuit, CT sampling circuit include A phase CT sampling circuit, and A phase CT sampling circuit includes that current transformer 2LHa, electric current are mutual
Sensor CTa and with the concatenated make and break contact JA2 of current transformer, A phase CT sampling circuit further includes one end and make and break contact JA2
The A phase energy converter Ta and the overcurrent tripping in parallel with make and break contact JA2 for connecting other end ground connection protect circuit, and overcurrent tripping is protected
Protection circuit include overcurrent release Y7 and with the concatenated make and break contact JA1 of overcurrent release Y7.
The beneficial effects of the utility model are: being added in A phase CT sampling circuit using above-mentioned self-powered microcomputer protecting device
The bridge contact for entering A phase energy converter Ta and driving driving overcurrent release, when short circuit accident occurs for power supply system, A phase energy converter
Ta acquires short circuit accident current energy, and converts and power to microcomputer protecting device, and microcomputer protecting device is worked normally,
Detection and differentiation, and starting protection action command are made to accident, avoid shielding failure.After starting protection movement, bridge contact
Make and break contact JA1 is first closed, and then make and break contact JA2 is disconnected again, during this protection act accesses current release,
Current transformer 2LHa secondary circuit is in Low ESR working condition always, and (i.e. current transformer 2LHa secondary side, which is in, is shorted shape
State), there is not open circuit phenomenon, avoiding secondary current circuit open circuit from generating, Keep Clear-High Voltage.Above-mentioned self-powered microcomputer protecting device
It can guarantee the stability of power supply system, and reduce the comprehensive project cost from distribution transforming user, simultaneously effective protect electricity
Current transformer and high-voltage switch gear cabinet equipment, and ensure the safety of operator on duty.
As preferential, CT sampling circuit further includes C phase CT sampling circuit, and C phase CT sampling circuit includes current transformer
2LHc, Current Transmit c and with the concatenated make and break contact JC2 of current transformer 2LHc, C phase CT sampling circuit further includes one
End connect the C phase energy converter Tc of other end ground connection with make and break contact JC2 and is connected in parallel on the overcurrent tripping at the both ends make and break contact JC2
Protect circuit, overcurrent tripping protection circuit include overcurrent release Y9 and with the concatenated make and break contact JC1 of overcurrent release Y9.
Using the structure, energy converter is also added in the C phase CT sampling circuit of self-powered microcomputer protecting device and driving driving overcurrent is de-
The bridge contact for detaining device, when short circuit accident occurs for power supply system, C phase energy converter Tc also acquires short circuit accident current energy simultaneously,
And convert and power to microcomputer protecting device, microcomputer protecting device is worked normally, detection and differentiation are made to accident, and open
Dynamic protection act order, avoids shielding failure.After starting protection movement, the make and break contact JC1 of bridge contact is first closed, and is then switched
Contact JC2 is disconnected again, and during this protection act accesses current release, current transformer 2LHc secondary circuit is always
In Low ESR working condition (i.e. current transformer 2LHc secondary side is in short circuit state), there is not open circuit phenomenon, avoid
Keep Clear-High Voltage for the open circuit generation of secondary current circuit.It can guarantee the stability of power supply system in this way, and reduce comprehensive from distribution transforming
The project cost of user simultaneously effective protects current transformer and high-voltage switch gear cabinet equipment, and ensures operator on duty
Safety.
As preferential, CT sampling circuit further includes B phase CT sampling circuit, and B phase CT sampling circuit includes current transformer
2LHb, Current Transmit b and with the concatenated make and break contact JB2 of current transformer 2LHb, B phase CT sampling circuit further includes one
End connect the B phase energy converter Tb of other end ground connection with make and break contact JB2 and is connected in parallel on the overcurrent tripping at the both ends make and break contact JB2
Protect circuit, overcurrent tripping protection circuit include overcurrent release Y8 and with the concatenated make and break contact JB1 of overcurrent release Y8.
Using the structure, energy converter is also added in the B phase CT sampling circuit of self-powered microcomputer protecting device and driving driving overcurrent is de-
The bridge contact for detaining device, when short circuit accident occurs for power supply system, B phase energy converter Tb also acquires short circuit accident current energy simultaneously,
And convert and power to microcomputer protecting device, microcomputer protecting device is worked normally, detection and differentiation are made to accident, and open
Dynamic protection act order, avoids shielding failure.After starting protection movement, the make and break contact JB1 of bridge contact is first closed, and is then switched
Contact JB2 is disconnected again, and during this protection act accesses current release, current transformer 2LHb secondary circuit is always
In Low ESR working condition (i.e. current transformer 2LHb secondary side is in short circuit state), there is not open circuit phenomenon, avoid
Keep Clear-High Voltage for the open circuit generation of secondary current circuit.It can guarantee the stability of power supply system in this way, and reduce comprehensive from distribution transforming
The project cost of user simultaneously effective protects current transformer and high-voltage switch gear cabinet equipment, and ensures operator on duty
Safety.
Detailed description of the invention
Fig. 1 is the working principle diagram of conventional microcomputer protecting device；
Fig. 2 is the working principle diagram that the self-powered microcomputer protecting device of two groups of bridge contacts is devised in the utility model；
Fig. 3 is the working principle diagram that the self-powered microcomputer protecting device of three groups of bridge contacts is devised in the utility model；
Specific embodiment
Utility model is further described referring to the drawings and in conjunction with specific embodiment, to enable those skilled in the art
Refer to the instruction text can be implemented accordingly, and scope of protection of the utility model is not limited to the specific embodiment.
The utility model relates to self-powered microcomputer protecting device, on the one hand having conventional has microcomputer under the conditions of working power
Overcurrent protection that protection philosophy has, fast tripping protection, overload protection, zero-sequence current protection, overvoltage protection, under-voltage protection
And the technical functionalities such as non electrical quantity gas temperature protection；On the other hand system outlet working power is too low or power supply of losing the job
In the case of, especially in the major accidents such as line load or bus phase fault, near point short circuit, system busbar voltage drop as low as
50% and hereinafter, original GPF (General Protection False is too low and ineffective because of working power, the self-powered Microcomputer Protection dress of the utility model
It sets in protection CT sampling circuit design energy converter and drives the bridge contact of overcurrent tripping coil, by the energy of fault current,
Starting current tripping fast tripping protection and current-release overcurrent protection, quickly and effectively cut off faulty line, overstepping are avoided to cause
(former GPF (General Protection False is in the too low situation of working power because shielding failure can only arrive upper level substation by bypassing the immediate leadership for the expansion of accident
Tripping cut off accident, cause the greater area of power failure of many normal users), greatly improve electricity supplying and using system in failure
The reliability protected in the case of accident.
It is as shown in Figure 1 the working principle diagram of conventional microcomputer protecting device, conventional microcomputer protecting device is all to pass through the external world
Working power provides back work power supply to circuits such as device single-chip microcontrollers, differentiates whether the electric current of acquisition is more than setting value, works as electricity
The movement tripping of high-tension switch cabinet breaking coil is connected in the movement of protective device exit relay when stream transfinites, and is played a protective role.On
The premise for stating reliably working is that have a reliable and stable back work power supply, and general electric system back work power supply is broadly divided into
Direct current 220V, direct current 110V and alternating current 220V, wherein DC220V, DC110V working power are using special DC power supply panel
It provides, this power mode is reliable and stable, and the larger substation of most of 10KV or more is all in this way.But
Small distribution transforming and case change, looped network controller switching equipment in a large amount of 10KV, due to not using by the small limitation in place and investment reduction etc.
DC power supply panel makees working power, but directlys adopt 10KV bus voltage transformer and be directly depressured to work of the alternating current 220V as equipment
Power supply.If the AC220V power loss or unstable, just influences whether the reliability of system protection equipment.The one exchange work
Although it is economical convenient and practical to make power supply, the reliability of its power supply cannot be guaranteed, will result in when buckling fuse failure
Secondary voltage phase shortage, power loss or line voltage decline etc., when especially big accident of power supply occurs for system (such as 10KV busbar short-circuit,
When outlet phase fault and near point short circuit accident), it will result in the decline of system 10KV busbar voltage, PT secondary side voltage instability
It is fixed, the working power voltage value of AC220V drop to sometimes 50% and hereinafter, cause the second protections such as microcomputer device equipment because
Working power is too low and shielding failure, cannot effectively and excision accident route.
The utility model relates to self-powered microcomputer protecting device, as shown in Fig. 2, including CT sampling circuit, CT samples back
Road includes A phase CT sampling circuit, B phase CT sampling circuit and C phase CT sampling circuit, and A phase CT sampling circuit includes Current Mutual Inductance
Device 2LHa, Current Transmit a and with the concatenated make and break contact JA2 of current transformer, A phase CT sampling circuit further includes one end
The A phase energy converter Ta and the overcurrent tripping in parallel with make and break contact JA2 that other end ground connection is connect with make and break contact JA2 are protected
Circuit, overcurrent tripping protection circuit include overcurrent release Y7 and with the concatenated make and break contact JA1 of overcurrent release Y7.CT is adopted
Sample circuit further includes C phase CT sampling circuit, C phase CT sampling circuit include current transformer 2LHc, Current Transmit c and
With the concatenated make and break contact JC2 of current transformer 2LHc, C phase CT sampling circuit further includes that one end is connect separately with make and break contact JC2
The C phase energy converter Tc of one end ground connection and the overcurrent tripping protection circuit for being connected in parallel on the both ends make and break contact JC2, overcurrent tripping protection
Circuit include overcurrent release Y9 and with the concatenated make and break contact JC1 of overcurrent release Y9.In Fig. 2, self-powered Microcomputer Protection
When device works normally, make and break contact JA2, make and break contact JC2 are first closed, and make and break contact JA1, make and break contact JC1 are disconnected again, electricity
The electric current that current transformer 2LHa, current transformer 2LHc are generated is less than the action current value of self-powered microcomputer protecting device setting,
A phase current is accessed by 101 terminals, is flowed through A phase inside protective device and is sampled CTa, JA2 normally closed contact and A phase energy converter Ta, then
It is picked out through 115 terminals, flows back to the A phase current mutual inductor 2LHa other end, form current closed-loop, at this moment A phase overcurrent tripping coil Y7
There is no electric current to flow through；C phase current is accessed by 103 terminals, is flowed through C phase inside protective device and is sampled CTc, JC2 normally closed contact and C
Phase energy converter Tc, then picked out through 117 terminals, the C phase current mutual inductor 2LHc other end is flowed back to, forms current closed-loop, at this moment C phase
Overcurrent tripping coil Y9 does not have electric current to flow through.When short circuit accident occurs for power supply system, A phase energy converter Ta, C phase energy converter Tc is adopted
Collect short circuit accident current energy (failure is bigger, and energy is bigger), and convert and power to microcomputer protecting device, so that Microcomputer Protection fills
Setting can work normally, and make detection and differentiation, and starting protection action command to accident, avoid shielding failure.Starting protection is dynamic
After work, in A phase CT sampling circuit, the make and break contact JA1 of bridge contact is first closed, and make and break contact JA2 is opened after about 50ms, and electric current is just
Overcurrent release Y7 is flowed through, during this protection act accesses current-release coil, secondary loop of mutual inductor is always
In Low ESR working condition (i.e. Current Transformer Secondary side is in short circuit state), there is not open circuit phenomenon, avoid secondary
Keep Clear-High Voltage for the generation of current loop open circuit.In C phase CT sampling circuit, the make and break contact JC1 of bridge contact is first closed, after about 50ms
Make and break contact JC2 is opened, and electric current flows through overcurrent release Y9, during this protection act accesses current-release coil,
Secondary loop of mutual inductor is in Low ESR working condition (i.e. Current Transformer Secondary side is in short circuit state) always, does not have
There is open circuit phenomenon, avoiding secondary current circuit open circuit from generating, Keep Clear-High Voltage.
As shown in figure 3, CT sampling circuit further includes B phase CT sampling circuit, B phase CT sampling circuit includes current transformer
2LHb, Current Transmit b and with the concatenated make and break contact JB2 of current transformer 2LHb, B phase CT sampling circuit further includes one
End connect the B phase energy converter Tb of other end ground connection with make and break contact JB2 and is connected in parallel on the overcurrent tripping at the both ends make and break contact JB2
Protect circuit, overcurrent tripping protection circuit include overcurrent release Y8 and with the concatenated make and break contact JB1 of overcurrent release Y8.
When self-powered microcomputer protecting device works normally, make and break contact JB 2 is first closed, and make and break contact JB1 is disconnected again, current transformer
The electric current that 2LHb is generated is less than the action current value of self-powered microcomputer protecting device setting, and B phase current is accessed by 102 terminals,
It flows through B phase inside protective device and samples CT, JB2 normally closed contact and B phase energy converter Tb, then picked out through 116 terminals, flow back to B phase electricity
The current transformer 2LHb other end forms current closed-loop, and at this moment B phase overcurrent release Y8 does not have electric current to flow through；When power supply system is sent out
When raw short circuit accident, B phase energy converter Tb acquires short circuit accident current energy (failure is bigger, and energy is bigger), and converts to microcomputer
Protective device power supply, enables microcomputer protecting device to work normally, and makes detection and differentiation, and starting protection movement life to accident
It enables, avoids shielding failure.After starting protection movement, in B phase CT sampling circuit, the make and break contact JB1 of bridge contact is closed, about 50ms
Make and break contact JB2 is opened afterwards, and electric current flows through overcurrent release Y8, accesses current-release coil process in this protection act
In, secondary loop of mutual inductor is in Low ESR working condition (i.e. Current Transformer Secondary side is in short circuit state) always,
There is not open circuit phenomenon, avoiding secondary current circuit open circuit from generating, Keep Clear-High Voltage.
Above-mentioned self-powered microcomputer protecting device, design have two sets of Microcomputer Protection principles, i.e., a set of conventional Microcomputer Protection is logical
The protection philosophy of overvoltage tripping and a set of current-release Microcomputer Protection principle independent of back work power supply, that is, possess
The abundant protection type configuration that conventional Microcomputer Protection has, and after can passing through after or power loss unstable in ac working power supply
Standby self-powered current-release protection effectively excision short circuit trouble point, so that the microcomputer protection system of exchange back work power supply is more
It is reliable and secure.
Above-mentioned self-powered microcomputer protecting device, adjoint high current institute when using catastrophe failures such as high-voltage fence generation short circuits
Energy is taken, the transducing circuit feedway working power designed by device works normally protective device microcomputer circuit, starting
The reliable excision short circuit malfunction of current-release protection.Energy converter is devised in CT sampling circuit and drives overcurrent release
Bridge contact, by the energy of fault current, starting current tripping fast tripping protection and current-release overcurrent protection (current-release protection
The external working power of device is not depended on, when device does not connect working power power loss, only fault current is needed to reach 3A or more
Can starter liquid crystal display and current-release protection), quickly and effectively cut off faulty line.It avoids in ac working power supply
Under occasion, former GPF (General Protection False defencive function in the case where working power voltage is too low or working power Disappearance Scenarios fails, so that accident
Expand, overstepping to upper level substation cuts off accident, causes the greater area of power failure of many normal users.
Claims (3)
1. a kind of self-powered microcomputer protecting device, including CT sampling circuit, CT sampling circuit includes A phase CT sampling circuit, special
Sign is: A phase CT sampling circuit include current transformer 2LHa, Current Transmit a and with current transformer is concatenated opens
Coila JA2, A phase CT sampling circuit further include one end connect with make and break contact JA2 the other end ground connection A phase energy converter Ta and
The overcurrent tripping in parallel with make and break contact JA2 protects circuit, overcurrent tripping protection circuit include overcurrent release Y7 and with mistake
Flow the concatenated make and break contact JA1 of buckle releaser Y7.
2. a kind of self-powered microcomputer protecting device according to claim 1, it is characterised in that: CT sampling circuit further includes C
Phase CT sampling circuit, C phase CT sampling circuit include current transformer 2LHc, Current Transmit c and and current transformer
2LHc concatenated make and break contact JC2, C phase CT sampling circuit further includes the C phase that one end connect other end ground connection with make and break contact JC2
Energy converter Tc and the overcurrent tripping protection circuit for being connected in parallel on the both ends make and break contact JC2, it includes overcurrent that overcurrent tripping, which protects circuit,
Buckle releaser Y9 and with the concatenated make and break contact JC1 of overcurrent release Y9.
3. a kind of self-powered microcomputer protecting device according to claim 2, it is characterised in that: CT sampling circuit further includes B
Phase CT sampling circuit, B phase CT sampling circuit include current transformer 2LHb, Current Transmit b and and current transformer
2LHb concatenated make and break contact JB2, B phase CT sampling circuit further includes the B phase that one end connect other end ground connection with make and break contact JB2
Energy converter Tb and the overcurrent tripping protection circuit for being connected in parallel on the both ends make and break contact JB2, it includes overcurrent that overcurrent tripping, which protects circuit,
Buckle releaser Y8 and with the concatenated make and break contact JB1 of overcurrent release Y8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920161420.6U CN209344750U (en) | 2019-01-30 | 2019-01-30 | A kind of self-powered microcomputer protecting device of belt current tripping |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920161420.6U CN209344750U (en) | 2019-01-30 | 2019-01-30 | A kind of self-powered microcomputer protecting device of belt current tripping |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN209344750U true CN209344750U (en) | 2019-09-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920161420.6U Expired - Fee Related CN209344750U (en) | 2019-01-30 | 2019-01-30 | A kind of self-powered microcomputer protecting device of belt current tripping |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN209344750U (en) |
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2019
- 2019-01-30 CN CN201920161420.6U patent/CN209344750U/en not_active Expired - Fee Related
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| CF01 | Termination of patent right due to non-payment of annual fee |