CN110380399A - A kind of DC traction power-supply system for eliminating residual voltage - Google Patents
A kind of DC traction power-supply system for eliminating residual voltage Download PDFInfo
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- CN110380399A CN110380399A CN201910710150.4A CN201910710150A CN110380399A CN 110380399 A CN110380399 A CN 110380399A CN 201910710150 A CN201910710150 A CN 201910710150A CN 110380399 A CN110380399 A CN 110380399A
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- 230000001681 protective effect Effects 0.000 claims abstract description 86
- 238000010521 absorption reaction Methods 0.000 claims abstract description 26
- 238000001514 detection method Methods 0.000 claims abstract description 25
- 230000004044 response Effects 0.000 claims abstract description 9
- 238000002955 isolation Methods 0.000 claims description 74
- 230000005611 electricity Effects 0.000 claims description 16
- 230000005540 biological transmission Effects 0.000 claims description 7
- 238000000034 method Methods 0.000 abstract description 15
- 238000005259 measurement Methods 0.000 description 8
- 239000000523 sample Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 3
- 208000027418 Wounds and injury Diseases 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 230000034994 death Effects 0.000 description 2
- 231100000517 death Toxicity 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 208000014674 injury Diseases 0.000 description 2
- 208000033748 Device issues Diseases 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000010485 coping Effects 0.000 description 1
- 230000005283 ground state Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J1/00—Circuit arrangements for dc mains or dc distribution networks
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Abstract
The invention discloses a kind of DC traction power-supply systems for eliminating residual voltage, belong to track power supply technique field.The present invention is set between power supply buses and rail, comprising: voltage detection circuit detects the voltage between contact net and rail and issues control protective unit；Contact net residual voltage absorption circuit, connect with contact net and rail respectively, absorbs contact net remaining voltage；Disconnecting switch powers for contact net in response to the instruction of control protective unit or contact net is isolated with bus or is grounded contact net；Control protective unit obtains voltage between contact net and rail, when the voltage is more than specified threshold, control contact net residual voltage absorption circuit work, until reaching normal value.The present invention effectively can quickly absorb contact net residual voltage；Line test is effectively carried out, is avoided on breaker closing to faulty line；Residual voltage quickly absorbs before contact net is grounded, and guarantees disconnecting switch without electrical ground.
Description
Technical field
The invention belongs to track power supply technique fields, and in particular to a kind of DC traction power-supply system for eliminating residual voltage.
Background technique
The high current generated in urban track traffic industry, line fault, vehicle start and stop is to threaten safe operation always
An important factor for.It is therefore prevented that in fault loop direct current quick breaker directly close a floodgate be ensure safe operation it is important because
Element.Chinese patent (patent No.: ZL201110416678.4) propose a kind of direct-current traction power supply feeder unit line test and
Guard method effectively avoids on breaker closing to faulty line, but there is no consideration contact net residual voltages, and route to be given to survey
Trying bring influences.Contact net residual voltage value is higher, which to be likely to result in line test, can't pass, can not be just so as to cause contact net
The result often powered.When general contact net residual voltage is greater than 300V, line test can not pass through, and switchgear cannot close a floodgate, and cause to connect
Touch net can not power transmission and directly affect parking.
In addition, in the tractive power supply system of urban track traffic, when needing to be serviced operation, for personal safety
Consider, open-circuit line is not only wanted to power, meanwhile, it also needs professional in operating area, power supply line is shorted and hangs ground, so as to
Prevent the unexpected personal injury powered and caused in operating area.But the contact net after having a power failure is also possible that residual high voltage, or
It is the situation that electric substation's misdelivery electricity is encountered during ground wire is hung, personnel are very easy to cause people when accidentally touching contact net
There is very big security risk in body electric shock injures and deaths, operating personnel.
In the Rail Transit System that various regions use, different coping styles is used to reduce shadow caused by contact net residual voltage
It rings.Currently, the measure that Chengdu subway is taken temporarily is adjusted to residual voltage detection definite value in direct-current switch cabinet line test,
It can not power transmission to avoid contact net；The measure that Tianjin light rail is taken is, contact net residual voltage value carries out on-site test, distinguish residual voltage and
Normal voltage；If it is determined that be residual voltage, then electric discharge and hanging earthing conductor, to reduce contact net residual voltage to line test and hanging earthing conductor
Influence.But the above method all rests on the state of manual work, not only serious waste human resources, and operating personnel exists very
Big security risk, far from meeting Automation of Electric Systems and intelligentized requirement.
Currently, quickly reducing contact net residual voltage by adopting an effective measure, line test and safety ground are made with reducing
At adverse effect, be the common difficulty that urban rail transit in China power supply industry faces.
Summary of the invention
It is an object of the present invention to provide a kind of DC traction power-supply systems for eliminating residual voltage, eliminate residual voltage and contact with intelligence
Net safety ground function.
Specifically, being set between power supply buses and rail the present invention provides following technical scheme, comprising:
Voltage detection circuit, the voltage detection circuit include the contact net voltage inspection between contact net and rail
Module is surveyed, which detects the voltage between contact net and rail and be sent to control protective unit；
Contact net residual voltage absorption circuit, connect with contact net and rail out of shape respectively, when work, absorbs contact net remaining electricity
Pressure；
Disconnecting switch is connect with bus and contact net respectively, is contact net in response to the instruction of the control protective unit
Contact net is isolated with bus for power supply；
Control protective unit obtains voltage between contact net and rail by the voltage detection circuit, when the voltage
When more than specified threshold, the contact net residual voltage absorption circuit work is controlled, until reaching normal value.
Furthermore, the contact net residual voltage absorption circuit, including the inhibition being series between contact net and rail
Element and first contactor；Instruction is absorbed in response to the residual voltage of control protective unit, first contactor is closed a floodgate, and contact net residual voltage is inhaled
Road conducting is withdrawn, straining element absorbs the residual voltage between contact net and rail.
Furthermore, the DC traction power-supply system further includes feeder line side line test trigger device, is parallel to and connects
The fast breaker touched net used in powering, the feeder line side line test in response to the control protective unit instruct, and trigger feeder line
Side line test；The voltage detection circuit further includes busbar voltage detection module between bus and rail and is located at
Feeder line side voltage detection module between feeder line and rail, is detected and is sent to the voltage of bus bar side and feeder line side respectively
To control protective unit；The control protective unit obtains bus bar side voltage and feeder line side electricity by the voltage detection circuit
Pressure judges whether busbar voltage normal and feeder line side line road no-voltage；If so, control protective unit is to the line test of feeder line side
Trigger device issues feeder line side line test instruction.
Furthermore, the feeder line side line test trigger device includes concatenated second contactor, high-tension fuse
And line test resistance, when needing to carry out the line test of feeder line side, protective device controls second contactor coil and is powered, and second
Probe of contactor closes the switch.
It furthermore, further include power supply indicating circuit and isolation indicating circuit, the disconnecting switch is two position switch,
One end is connect with contact net, and the other end is connect with feeder line side, drives two position switch to close a floodgate by third contactor, at this time two stations
Disconnecting switch is in for electric position, and indicating circuit of powering sends power indicator signal to control protective unit；By the 4th contactor
Drive two position switch by for electric position separating brake, indicating circuit transmission isolation indication signal is isolated after the completion and gives control protection for separating brake
Device.
Furthermore, the DC traction power-supply system further include: two button switches control disconnecting switch respectively
Power supply and isolated operation, generate corresponding power supplying control signal and isolation control signal, and be sent to control protective unit；It is described
When control protective unit receives power supplying control signal, control third contactor drives two position switch to close a floodgate；Receive isolation
When controlling signal, the 4th contactor of control drives two position switch by for electric position separating brake.
It furthermore, further include power supply indicating circuit, ground connection indicating circuit and isolation indicating circuit, the disconnecting switch
It is isolated or connects with bus for contact net power supply, by contact net in response to the instruction of the control protective unit for three-station
Ground, first terminal are connect with contact net, and Second terminal is connect with feeder line side, third terminal ground connection；Three are driven by third contactor
Position switch closes a floodgate, and tri-station isolating switch is in for electric position at this time, and indicating circuit of powering sends power indicator signal to control
Protective device processed；Three-station is driven to close a floodgate by the 5th contactor, tri-station isolating switch is in earthing position at this time, ground connection
Indicating circuit sends ground connection indication signal to control protective unit；Drive three-station by for electric position point by the 4th contactor
Indicating circuit is isolated after the completion and sends isolation indication signal to control protective unit for lock, separating brake；Three works are driven by the 6th contactor
Bit switch by earthing position separating brake, indicating circuit is isolated after the completion and sends isolation indication signal to control protective unit by separating brake.
Furthermore, the DC traction power-supply system further include: three button switches control disconnecting switch respectively
Power supply, ground connection and isolated operation generate corresponding power supplying control signal, isolation control signal and ground connection control signal, and send
To control protective unit；When the control protective unit receives power supplying control signal, control third contactor drives three stations
Switch closes a floodgate；When receiving isolation control signal, the 4th contactor is controlled in conjunction with received power indicator signal and drives three stations
Switch drives three-station by being grounded by controlling the 6th contactor for electric position separating brake or the received ground connection indication signal of combination
Position separating brake；When receiving ground connection control signal, the 5th contactor of control drives three-station to close a floodgate.
Beneficial effects of the present invention are as follows:
DC traction power-supply system of the invention before carrying out line test, is detected by adding residual voltage absorption plant
When contact net residual voltage is excessive, residual voltage absorption can be first carried out, when reaching normal voltage value, just allows to carry out line test；?
Before disconnecting switch ground connection, to avoid residual voltage bring personal injury, it can first carry out residual voltage and absorb to reduce residual voltage, until reaching peace
After full voltage, disconnecting switch is grounded again.In addition, by reducing security risk instead of manual work using disconnecting switch.
Detailed description of the invention
Fig. 1 is the residual voltage principle of absorption schematic diagram of the embodiment of the present invention 1 and 2.
Fig. 2 is the circuit diagram of the embodiment of the present invention 1.
Fig. 3 is the circuit diagram of the embodiment of the present invention 2.
The meaning of each component and effect are as follows in Fig. 2 and Fig. 3:
R1: it for straining element, is absorbed for contact net residual voltage；
K1: it for first contactor switch contacts, is connected for residual voltage absorption circuit；
QF: it for fast breaker, is used to power to railway traffic contact network；
F1: for high-tension fuse, for preventing route survey circuit over current fault；
K2: for second contactor switch contacts, circuit is measured for conducting voltage；
R2: for line test resistance, for measuring circuit current limliting；Voltage class 900V:30 Ω, voltage class 1800V:60
Ω；
U1: bus voltage measurement amplifier is measured for busbar voltage Ur；
U2: feeder voltage measuring amplifier is measured for feeder voltage Uf；
U3: contact net voltage measurement amplifier is measured for contact net voltage Uc；
Q1: for first contactor coil, being controlled by control protective unit, control switch K1 shutdown；
Q2: for second contactor coil, being controlled by control protective unit, control switch K2 shutdown；
Q3: for third contactor coil, being controlled by control protective unit, control switch K3 shutdown；
Q4: for the 4th contactor coil, being controlled by control protective unit, control switch K4 shutdown；
Q5: for the 5th contactor coil, being controlled by control protective unit, control switch K5 shutdown；
Q6: for the 6th contactor coil, being controlled by control protective unit, control switch K6 shutdown；
K3: for third probe of contactor switch, for motor forward loop be connected, drive disconnecting switch close a floodgate, this after
It leaves pass to be in for electric position (disconnecting switch moving contact is located at " 1 " position), busbar voltage is contact net confession through QF, disconnecting switch
The conducting of electricity, i.e. power supply line；
K4: driving disconnecting switch separating brake for the conducting of motor reverse circuit for the 4th probe of contactor switch, this after
Leave pass and be in isolated location (disconnecting switch moving contact is located at " 0 " position), at this time contact net and power supply line, ground path every
From；
K5: driving disconnecting switch to close a floodgate for the 5th probe of contactor switch for the conducting of motor reverse circuit, this after
It leaves pass and is in earthing position (disconnecting switch moving contact is located at " 2 " position), the grounded line of contact net is connected with return current rail, that is, connects
Ground line conduction；
K6: for the 6th probe of contactor switch, for motor forward loop be connected, drive disconnecting switch separating brake, this after
Leave pass and be in isolated location (disconnecting switch moving contact is located at " 0 " position), at this time contact net and power supply line, ground path every
From；
E1: for button switch, disconnecting switch combined floodgate power supply is controlled；
E2: it for button switch, controls disconnecting switch and closes a floodgate for electrical ground；
E3: for button switch, the isolation of disconnecting switch separating brake is controlled；
K3-1, K3-2, K3-3: for the auxiliary contact of switch contacts K3；
K4-1, K4-2, K4-3: for the auxiliary contact of switch contacts K4；
K5-1, K5-2, K5-3: for the auxiliary contact of switch contacts K5；
K6-1, K6-2, K6-3: for the auxiliary contact of switch contacts K6；
QS: tri-station isolating switch can make contact net (rail) and walking rail, it can be achieved that power supply, isolation, grounding function
Between formed the circuit direct current 750V/1500V, can also be in overhaul of the equipments, by contact net safety ground.
QS*: two station disconnecting switchs can make between contact net (rail) and walking rail, it can be achieved that two power supply, isolation functions
Form the circuit direct current 750V/1500V.
QS1-1a, QS1-1b, QS1-2: disconnecting switch auxiliary contact.When disconnecting switch is closed a floodgate, (moving contact is moved by position reset
Move " 1 ") when, QS1-1b, QS1-2 become normally closed by normally opened, and QS1-1a becomes normally opened by normally closed, control protective unit A0 with
The pin that QS1-2 connects generates high level signal, this is power indicator signal；When (moving contact is by position set for disconnecting switch separating brake
It is moved to " 0 ") when, QS1-1a, QS1-1b, QS1-2 set back (referred to as involution).
QS2-1a, QS2-1b, QS2-2: disconnecting switch auxiliary contact.When disconnecting switch is closed a floodgate, (moving contact is moved by position reset
Move " 2 ") when, QS2-1b, QS2-2 become normally closed by normally opened, and QS2-1a becomes normally opened by normally closed, control protective unit A0 with
The pin that QS2-2 connects generates high level signal, this is ground connection indication signal；When disconnecting switch separating brake, (moving contact is by position
" 2 " are moved to " 0 "), QS2-1a, QS2-1b, QS2-2 set back (referred to as involution).
QS0-1: disconnecting switch auxiliary contact, when disconnecting switch is closed a floodgate, (moving contact is moved to " 1 " by position reset or is moved
Contact is moved to " 2 " by position reset), QS0-1 becomes normally opened by normally closed；The pin that control protective unit A0 connects with QS0-1 produces
Indication signal is isolated at this time and disappears for raw low level signal；When disconnecting switch separating brake (moving contact by position set be moved to " 0 " or
Moving contact is moved to " 0 " by position " 2 "), QS0-1 sets back (involution), the pin that control protective unit A0 connects with QS0-1
High level signal is generated, this is isolation indication signal.
A0: control protective unit, one kind of controller, can receive and handle bus voltage signal, feeder voltage signal,
The ground connection of contact net voltage signal and disconnecting switch, isolation, power indicator signal also can control contactor to cut-off.
Specific embodiment
Below with reference to embodiment and referring to attached drawing, present invention is further described in detail.
Embodiment 1:
One embodiment of the present of invention, for a kind of DC traction power-supply system for eliminating residual voltage.As shown in Figure 1, contacting
Increase contact net residual voltage absorption circuit (including straining element and contactor) between net and rail out of shape, incremental contact net voltage sample
Circuit, and control protective unit existing in feeder line test macro is relied on, contact is realized using straining element and contactor
The absorption of net residual voltage.
Before carrying out feeder line test, control protective unit pass through the voltage sampling signal that receives judge contact net and
Whether residual voltage is more than threshold value between rail.When residual voltage is more than threshold value, control protective unit control contactor closes a floodgate, and residual voltage absorbs
Circuit conducting, straining element absorb residual voltage, until after contact net voltage reaches normal voltage, then feeder line test is carried out, directly
Pass through ability combined floodgate feeder breaker to line test.
When needing plant maintenance to overhaul, before online disconnecting switch ground connection, control protective unit passes through the electricity received
Pressure sampled signal judges for residual voltage whether there is or not residual voltage, whether residual voltage is more than threshold value between contact net and rail.When residual voltage is more than threshold
When value, inhibit residual voltage using residual voltage absorptive unit, after reaching safe voltage, just controls disconnecting switch ground connection.
In the DC traction power-supply system for eliminating residual voltage and contact net safety ground function with intelligence as shown in Figure 2,
Working principle is as follows.
The judgement and absorption process of contact net residual voltage:
Before line test and before tri-station isolating switch ground connection, the judgement for carrying out contact net residual voltage is required, and necessary
Shi Jinhang contact net residual voltage absorbs, and tri-station isolating switch is in isolation at this time.Process is as follows:
Collected contact net voltage signal is sent control protective unit by voltage measurement amplifier U3, and protective device connects
Voltage signal is received, and distinguishes residual voltage and normal voltage, if it is determined that (depending on operating condition, range 0V to 1500V is not for residual voltage
Deng), then control contactor coil Q1 is powered, and Q1 is closed contactless contactor K1, the conducting of residual voltage absorption circuit, straining element R1
(power requirement is greater than or equal to 30W, and impedance is more than or equal to 160k Ω, is less than or equal to 240k Ω) absorbs residual voltage, until reaching just
Normal voltage, control protective unit control residual voltage absorptive unit and stop residual voltage absorption work.
Line test procedure:
Before direct current quick breaker QF combined floodgate, after residual voltage absorbs work, line test is carried out.Bus voltage measurement
Busbar voltage U in amplifier U1 and feeder voltage measuring amplifier U2 measurement DC traction systemrWith feeder line side voltage Uf；Control
Protective device A0 processed obtains busbar voltage UrWith feeder line side voltage UfIf there is busbar voltage UrIt works not less than feeder line minimum electric
Press UflowAnd feeder voltage UfNo more than the route residual voltage U of settingfresidue, show that busbar voltage is normal, feeder line side line Lu Wu electricity
Pressure；At this time because residual voltage has disappeared, can judge whether route is normal with the method for measurement line resistance.And it is inhaled increasing residual voltage
Before receiving unit, for the method (method of measurement line resistance) because being influenced by residual voltage, maximum probability causes line test can't pass, and influences
Normal power supply.Specifically: control protective unit control contactor coil Q2 is powered, so that it is closed probe of contactor switch K2,
Then busbar voltage is applied to feeder line side by F1 and R2, and device calculates feeder line side loop resistance Rre.Its calculation method is as follows:
Rre=R2*Uf/((Ur-Uf)Rcalibration)；
Wherein RcalibrationFor route calibrating resistance, it to be used for compensating line R2 trueness error itself, value range 27000~
65000m Ω (milliohm).
If feeder line side loop resistance RreMore than threshold value Rmin(RminValue range be 300~10000m Ω), i.e. Rre≥
Rmin, then it is assumed that feeder assembly fault-free, direct current quick breaker can directly close a floodgate；If measuring feeder line side loop resistance Rre
< Rmin, then it is considered as short circuit, control protective unit A0 issues locking fast breaker QF switching signal.
Contact net safety ground process:
1) original state
Tri-station isolating switch QS is in isolated bit, and auxiliary contact QS0-1 is in closed state, and isolation instruction route is in
On state send isolation indication signal, control protective unit A0 by receive isolation indication signal detection and isolation switch be in every
It offs normal and sets and current isolation (or passing through indicator light) is shown by display.
2) it powers and is isolated
Power supply:
When needing tri-station isolating switch QS combined floodgate power supply, by lower button E1, power supplying control signal line conduction, control
Protective device A0 receives power supplying control signal, if tri-station isolating switch is in isolated location at this time for judgement, controls rapidly
Contactor coil Q3 is powered, and Q3 is closed contactless contactor K3, and the conducting of motor forward loop drives disconnecting switch to close a floodgate, at this time
Disconnecting switch is in for electric position (" 1 " position), and busbar voltage is contact net power supply through QF, disconnecting switch, i.e., power supply line is normal
Conducting power supply.
When coil Q3 is powered, auxiliary contact K3-3 closure keeps circuit conducting.
When coil Q3 is powered, auxiliary contact K3-1 is opened, and guarantees that Q4 is in off state, avoids (such as missing because of maloperation
Press isolation button or control protective unit mistaking signal) triggering contact net be isolated with power supply line, ground path, to give
Disconnecting switch is closed a floodgate to power and be affected.
When coil Q3 is powered, auxiliary contact K3-2 is opened, and guarantees that Q5 is in off state, avoids (such as missing because of maloperation
Press ground connection button or control protective unit mistaking signal) triggering contact net ground path conducting, to close a floodgate to disconnecting switch
Power supply affects.
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS1-1a to disconnect, and contactor coil Q3 control loop is disconnected
Electricity, at this time contactor coil Q3 power loss, corresponding contactless contactor K3 and auxiliary contact K3-1, K3-2 and K3-3 involution.
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS1-1b closure, and contactor coil Q4 control loop connects
It is logical, disconnecting switch can be controlled by E3 at this time return " 0 " position.
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS1-2 closure, and power supply instruction line conduction, which is sent, to be supplied
Electric indication signal, control protective unit A0 are in power supply closing position by reception power indicator signal detection and isolation switch and lead to
It crosses display and shows current power supply state (or passing through indicator light).
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS0-1 to disconnect, and isolation instruction route is in power loss shape
State.
Isolation:
When needing tri-station isolating switch power-off isolation, by lower button E3, isolation control signal line conduction, control is protected
Protection unit A0 receives isolation control signal, if tri-station isolating switch is in for electric position at this time for judgement, control is connect rapidly
Tentaculum coil Q4 is powered, and (coil Q6 is in parallel with coil Q4, is controlled by the same output point of A0, but Q6 controls route in open circuit at this time
State, Q6 will not be powered), Q4 is closed contactless contactor K4, and the reverse circuit conducting of motor drives disconnecting switch separating brake, at this time
Disconnecting switch is in isolated location (" 0 " position), and contact net is isolated with power supply line, ground path.
When coil Q4 is powered, auxiliary contact K4-3 closure keeps circuit conducting.
When coil Q4 is powered, auxiliary contact K4-1 is opened, and is guaranteed that Q3 is in off state, is avoided maloperation (accidentally by power supply
Button or control protective unit mistaking signal) conducting of triggering contact net power supply line, to come to disconnecting switch separating brake isolation strip
It influences.
When coil Q4 is powered, auxiliary contact K4-2 is opened, and is guaranteed that Q6 is in off state, is avoided the direction of motion between K6 and K4
It is inconsistent, occur maloperation (control protective unit mistaking signal), to be affected to the isolation of disconnecting switch separating brake.
Tri-station isolating switch QS separating brake drives linkage auxiliary contact QS1-1b to disconnect, and contactor coil Q4 control loop is disconnected
Electricity, at this time contactor coil Q4 power loss, corresponding contactless contactor K4 and auxiliary contact K4-1, K4-2 and K4-3 involution.
Tri-station isolating switch QS separating brake drives linkage auxiliary contact QS1-1a closure, and contactor coil Q3 control loop connects
It is logical, disconnecting switch can be controlled by E1 at this time return " 1 " position.
Tri-station isolating switch QS separating brake drive linkage auxiliary contact QS0-1 closure, isolation instruction line conduction send every
From indication signal, control protective unit A0 is in isolated location and by aobvious by receiving isolation indication signal detection and isolation switch
Show that device shows current isolation (or passing through indicator light).
Tri-station isolating switch QS separating brake drives linkage auxiliary contact QS1-2 to disconnect, and power supply instruction route is in power loss shape
State.
3) it is grounded and is isolated
Ground connection:
When needing to power off progress upkeep operation, considers in the person, after cut-off breaker, also contact net is needed to be grounded,
The method of the artificial mounting short-circuit line of the invention abandoning tradition realizes automatic earthing using tri-station isolating switch, reduces personnel
Injures and deaths.It needs to carry out residual voltage absorption using residual voltage absorptive unit before ground connection, avoids being grounded under electriferous state, cause line tripping,
Influence normal power supply.Residual voltage judges that absorption process is as follows:
Short-circuiting device QF is disconnected, and tri-station isolating switch is made to be in isolated location, voltage measurement amplifier U3 detection contact
Voltage between net and cathode, control protective unit receive this voltage, if judging no-voltage or in safe voltage, the isolation of three stations
Switch ground connection；If judgement is more than safe voltage, control contactor coil Q1 is powered, and Q1 is closed contactless contactor K1, residual voltage
Absorption circuit conducting, straining element R1 absorb residual voltage, until reach safe voltage, control tri-station isolating switch ground connection, ground connection
Shi Buxu short distance manual operation ground connection, only needs remote-controlled grounding, ensure that personal safety.Ground connection process is as follows:
When needing tri-station isolating switch QS combined floodgate ground connection, by lower button E2, it is grounded control signal lines conducting, at this time
Control protective unit A0 receives ground connection control signal, if tri-station isolating switch is in isolated location at this time for judgement, rapidly
Control contactor coil Q5 is powered, and Q5 is closed contactless contactor K5, and the reverse circuit conducting of motor drives disconnecting switch to close a floodgate,
Disconnecting switch is in earthing position (" 2 " position) at this time, and the grounded line of contact net is connected with return current rail, i.e., ground path is connected.
When coil Q5 is powered, auxiliary contact K5-3 closure keeps circuit conducting.
When coil Q5 is powered, auxiliary contact K5-1 is opened, and is guaranteed that Q3 is in off state, is avoided maloperation (accidentally by power supply
Button or control protective unit mistaking signal) conducting of triggering contact net power supply line, to give disconnecting switch combined floodgate counterpoise grounding
To influence.
When coil Q5 is powered, auxiliary contact K5-2 is opened, and is guaranteed that Q6 is in off state, is avoided maloperation (accidentally by isolation
Button or control protective unit mistaking signal) triggering contact net is isolated with power supply line, ground path, to be kept apart
Lock ground connection is closed to affect.
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS2-1a to disconnect, and contactor coil Q5 control loop is disconnected
Electricity, at this time contactor coil Q5 power loss, corresponding contactless contactor K5 and auxiliary contact K5-1, K5-2 and K5-3 involution.
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS2-1b closure, and contactor coil Q6 control loop connects
It is logical, disconnecting switch can be controlled by E3 at this time return " 0 " position.
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS2-2 closure, and ground connection instruction line conduction transmission connects
Ground indication signal, control protective unit A0 are in contact of earth position and lead to by receiving ground connection indication signal detection and isolation switch
It crosses display and shows current ground state (or passing through indicator light).
Tri-station isolating switch QS, which closes a floodgate, drives linkage auxiliary contact QS0-1 to disconnect, and isolation instruction route is in power loss shape
State.
Isolation:
When needing tri-station isolating switch power-off isolation, by lower button E3, isolation control signal line conduction, control is protected
Protection unit A0 receives isolation control signal, if tri-station isolating switch is in earthing position at this time for judgement, control is connect rapidly
Tentaculum coil Q6 is powered, and (coil Q6 is in parallel with coil Q4, is controlled by the same output point of A0, but Q4 controls route in open circuit at this time
State, Q4 will not be powered), Q6 is closed contactless contactor K6, and the conducting of motor forward loop drives disconnecting switch separating brake, at this time
Disconnecting switch is in isolated location (" 0 " position), and contact net is isolated with power supply line, ground path.
When coil Q6 is powered, auxiliary contact K6-3 closure keeps circuit conducting.
When coil Q6 is powered, auxiliary contact K6-1 is opened, and is guaranteed that Q4 is in off state, is avoided the direction of motion between K4 and K6
It is inconsistent, occur maloperation (control protective unit mistaking signal), to be affected to the isolation of disconnecting switch separating brake.
When coil Q6 is powered, auxiliary contact K6-2 is opened, and is guaranteed that Q5 is in off state, is avoided maloperation (accidentally by ground connection
Button or control protective unit mistaking signal) triggering contact net ground path conducting, to come to disconnecting switch separating brake isolation strip
It influences.
Tri-station isolating switch QS separating brake drives linkage auxiliary contact QS2-1b to disconnect, and contactor coil Q6 control loop is disconnected
Electricity, at this time contactor coil Q6 power loss, corresponding contactless contactor K6 and auxiliary contact K6-1, K6-2 and K6-3 involution.
Tri-station isolating switch QS separating brake drives linkage auxiliary contact QS2-1a closure, and contactor coil Q5 control loop connects
It is logical, disconnecting switch can be controlled by E2 at this time return " 2 " position.
Tri-station isolating switch QS separating brake drive linkage auxiliary contact QS0-1 closure, isolation instruction line conduction send every
From indication signal, control protective unit A0 is in isolated location and by aobvious by receiving isolation indication signal detection and isolation switch
Show that device shows current isolation (or passing through indicator light).
Tri-station isolating switch QS separating brake drives linkage auxiliary contact QS2-2 to disconnect, and ground connection instruction route is in power loss shape
State.
Embodiment 2:
Another embodiment of the invention, for a kind of DC traction power-supply system for eliminating residual voltage.As shown in figure 3, with reality
Applying 1 something in common of example is, contact net residual voltage absorption circuit (including straining element and contact are arranged between contact net and rail out of shape
Device), contact net voltage sample circuit, pass through control protective unit, control contact net residual voltage absorption circuit realize contact net residual voltage
Absorption；Difference from Example 1 is, using two station disconnecting switchs, rather than tri-station isolating switch.
It needs to carry out the judgement of contact net residual voltage before line test, and carries out the absorption of contact net residual voltage when necessary, at this time
Two station disconnecting switchs are in isolation, and the judgement of contact net residual voltage and absorption process are similar with embodiment 1.
As shown in Figure 3 eliminates two station disconnecting switchs work in the DC traction power-supply system of residual voltage function with intelligence
Mode is as follows.
1) original state
Two station disconnecting switch QS are in isolated bit, and auxiliary contact QS0-1 is in closed state, and isolation instruction route is in
On state send isolation indication signal, control protective unit A0 by receive isolation indication signal detection and isolation switch be in every
It offs normal and sets and current isolation (or passing through indicator light) is shown by display.
2) it powers and is isolated
Power supply:
When needing two station disconnecting switch QS combined floodgate power supply, by lower button E1, power supplying control signal line conduction, control
Protective device A0 receives power supplying control signal, if disconnecting switch is in isolated location, rapid control contactor at this time for judgement
Coil Q3 is powered, and Q3 is closed contactless contactor K3, and the conducting of motor forward loop drives disconnecting switch to close a floodgate, keeps apart at this time
Pass is in for electric position (" 1 " position), the power supply of power supply line's normally.
When coil Q3 is powered, auxiliary contact K3-2 closure keeps circuit conducting.
When coil Q3 is powered, auxiliary contact K3-1 is opened, and is guaranteed that Q4 is in off state, is avoided maloperation (accidentally by isolation
Button or control protective unit mistaking signal) triggering contact net is isolated with power supply line, to be supplied to closing a floodgate to disconnecting switch
Electricity affects.
Two station disconnecting switch QS, which close a floodgate, drives linkage auxiliary contact QS1-1a to disconnect, and contactor coil Q3 control loop is disconnected
Electricity, at this time contactor coil Q3 power loss, corresponding contactless contactor K3 and auxiliary contact K3-1, K3-2 involution.
Two station disconnecting switch QS, which close a floodgate, drives linkage auxiliary contact QS1-1b closure, and contactor coil Q4 control loop connects
It is logical, disconnecting switch can be controlled by E2 at this time return " 0 " position.
Two station disconnecting switch QS, which close a floodgate, drives linkage auxiliary contact QS1-2 closure, and power supply instruction line conduction, which is sent, to be supplied
Electric indication signal, control protective unit A0 are in power supply closing position by reception power indicator signal detection and isolation switch and lead to
It crosses display and shows current power supply state (or passing through indicator light).
Two station disconnecting switch QS, which close a floodgate, drives linkage auxiliary contact QS0-1 to disconnect, and isolation instruction route is in power loss shape
State.
Isolation:
When needing the power-off isolation of two station disconnecting switchs, by lower button E2, isolation control signal line conduction, this time control
Protective device A0 processed receives isolation control signal, then rapid control contactor coil Q4 is powered, and Q4 closes contactless contactor K4
Close, the conducting of motor reverse circuit drives disconnecting switch separating brake, and disconnecting switch is in isolated location (" 0 " position) at this time, contact net with
Power supply line's isolation.
When coil Q4 is powered, auxiliary contact K4-2 closure keeps circuit conducting.
When coil Q4 is powered, auxiliary contact K4-1 is opened, and is guaranteed that Q3 is in off state, is avoided maloperation (accidentally by power supply
Button or control protective unit mistaking signal) conducting of triggering contact net power supply line, to come to disconnecting switch separating brake isolation strip
It influences.
Two station disconnecting switch QS separating brakes drive linkage auxiliary contact QS1-1b to disconnect, and contactor coil Q4 control loop is disconnected
Electricity, at this time contactor coil Q4 power loss, corresponding contactless contactor K4 and auxiliary contact K4-1, K4-2 involution.
Two station disconnecting switch QS separating brakes drive linkage auxiliary contact QS1-1a closure, and contactor coil Q3 control loop connects
It is logical, disconnecting switch can be controlled by E1 at this time return " 1 " position.
Two station disconnecting switch QS separating brakes drive linkage auxiliary contact QS0-1 closure, isolation instruction line conduction send every
From indication signal, control protective unit A0 is in isolated location and by aobvious by receiving isolation indication signal detection and isolation switch
Show that device shows current isolation (or passing through indicator light).
Two station disconnecting switch QS separating brakes drive linkage auxiliary contact QS1-2 to disconnect, and power supply instruction route is in power loss shape
State.
Although the present invention has been described by way of example and in terms of the preferred embodiments, embodiment is not for the purpose of limiting the invention.Not
It is detached from the spirit and scope of the present invention, any equivalent change or retouch done also belongs to the protection scope of the present invention.Cause
This protection scope of the present invention should be based on the content defined in the claims of this application.
Claims (8)
1. a kind of DC traction power-supply system for eliminating residual voltage, is set between power supply buses and rail, which is characterized in that packet
It includes:
Voltage detection circuit, the voltage detection circuit include the contact net voltage detecting mould between contact net and rail
Block, the module detect the voltage between contact net and rail and are sent to control protective unit；
Contact net residual voltage absorption circuit, connect with contact net and rail out of shape respectively, when work, absorbs contact net remaining voltage；
Disconnecting switch is connect with bus and contact net respectively, in response to the instruction of the control protective unit, is powered for contact net
Or contact net is isolated with bus；
Control protective unit obtains voltage between contact net and rail by the voltage detection circuit, when the voltage is more than
When specified threshold, the contact net residual voltage absorption circuit work is controlled, until reaching normal value.
2. the DC traction power-supply system according to claim 1 for eliminating residual voltage, which is characterized in that the contact net residual voltage
Absorption circuit, including the straining element being series between contact net and rail and first contactor；In response to control protection dress
The residual voltage set absorbs instruction, and first contactor is closed a floodgate, and contact net residual voltage absorption circuit conducting, straining element absorbs contact net and walks
Residual voltage between row rail.
3. the DC traction power-supply system according to claim 1 for eliminating residual voltage, which is characterized in that further include feeder line side line
Drive test tries trigger device, contact net power supply fast breaker used is parallel to, in response to the feeder line of the control protective unit
Side line test instruction, triggers the line test of feeder line side；
The voltage detection circuit further include busbar voltage detection module between bus and rail and be located at feeder line with
Feeder line side voltage detection module between rail, respectively detects the voltage of bus bar side and feeder line side and is sent to control
Protective device；
The control protective unit obtains bus bar side voltage and feeder line side voltage by the voltage detection circuit, judges bus
Whether voltage normal and feeder line side line road no-voltage；If so, control protective unit is sent out to feeder line side line test trigger device
The line test of feeder line side instructs out.
4. the DC traction power-supply system according to claim 3 for eliminating residual voltage, which is characterized in that feeder line side line road
Test trigger device includes concatenated second contactor, high-tension fuse and line test resistance, when needing to carry out feeder line side line
When drive test tries, protective device controls second contactor coil and is powered, second contactor switch contacts closure.
5. the DC traction power-supply system according to any one of claims 1 to 4 for eliminating residual voltage, which is characterized in that further include
Power indicating circuit and isolation indicating circuit, the disconnecting switch be two position switch, one end connect with contact net, the other end and
The connection of feeder line side,
Two position switch are driven to close a floodgate by third contactor, two station disconnecting switchs are in for electric position, power supply instruction electricity at this time
Road sends power indicator signal to control protective unit；
Drive two position switch by for electric position separating brake, indicating circuit transmission isolation is isolated after the completion and refers to for separating brake by the 4th contactor
Show signal to control protective unit.
6. the DC traction power-supply system according to claim 5 for eliminating residual voltage, which is characterized in that further include:
Two button switches, respectively control disconnecting switch power supply and isolated operation, generate corresponding power supplying control signal and every
From control signal, and it is sent to control protective unit；
When the control protective unit receives power supplying control signal, control third contactor drives two position switch to close a floodgate；It connects
When receiving isolation control signal, the 4th contactor of control drives two position switch by for electric position separating brake.
7. the DC traction power-supply system according to any one of claims 1 to 4 for eliminating residual voltage, which is characterized in that further include
Power supply indicating circuit, ground connection indicating circuit and isolation indicating circuit, the disconnecting switch is three-station, in response to the control
The instruction of protective device processed is isolated or is grounded with bus for contact net power supply, by contact net, and first terminal is connect with contact net,
Second terminal is connect with feeder line side, third terminal ground connection；
Three-station is driven to close a floodgate by third contactor, tri-station isolating switch is in for electric position, power supply instruction electricity at this time
Road sends power indicator signal to control protective unit；
Three-station is driven to close a floodgate by the 5th contactor, tri-station isolating switch is in earthing position, ground connection instruction electricity at this time
Road sends ground connection indication signal to control protective unit；
Drive three-station by for electric position separating brake, indicating circuit transmission isolation is isolated after the completion and refers to for separating brake by the 4th contactor
Show signal to control protective unit；
Drive three-station by earthing position separating brake by the 6th contactor, indicating circuit transmission isolation is isolated after the completion and refers to for separating brake
Show signal to control protective unit.
8. the DC traction power-supply system according to claim 7 for eliminating residual voltage, which is characterized in that further include:
Three button switches control power supply, ground connection and the isolated operation of disconnecting switch respectively, generate corresponding power supply control letter
Number, isolation control signal and ground connection control signal, and be sent to control protective unit；
When the control protective unit receives power supplying control signal, control third contactor drives three-station to close a floodgate；It connects
When receiving isolation control signal, the 4th contactor is controlled in conjunction with received power indicator signal and drives three-station by for current potential
Setting separating brake or received ground connection indication signal is combined to control the 6th contactor drives three-station by earthing position separating brake；It receives
When controlling signal to ground connection, the 5th contactor of control drives three-station to close a floodgate.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910710150.4A CN110380399B (en) | 2019-08-02 | 2019-08-02 | DC traction power supply system for eliminating residual voltage |
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|---|---|---|---|
| CN201910710150.4A CN110380399B (en) | 2019-08-02 | 2019-08-02 | DC traction power supply system for eliminating residual voltage |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117155145A (en) * | 2023-08-30 | 2023-12-01 | 广州泰达创盈电气有限公司 | Discharge device and discharge system |
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| CN110380399B (en) | 2024-05-07 |
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