CN209029909U - Transformer neutral point DC isolation device based on jet plasma trigger switch - Google Patents
Transformer neutral point DC isolation device based on jet plasma trigger switch Download PDFInfo
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- CN209029909U CN209029909U CN201822079546.7U CN201822079546U CN209029909U CN 209029909 U CN209029909 U CN 209029909U CN 201822079546 U CN201822079546 U CN 201822079546U CN 209029909 U CN209029909 U CN 209029909U
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Abstract
The utility model discloses a kind of transformer neutral point DC isolation device based on jet plasma trigger switch, including controlling and triggering system, first earthing knife-switch, second earthing knife-switch, fast protecting switch based on jet plasma trigger switch, metallic contact protective switch, capacitance, current detector for detecting the voltage detector of capacitance two sides voltage and for detecting capacitance electric current, control and triggering system include control system and triggering system, the device meets the requirement of centre-point earth impedance, the problem of there is no thyristor damages simultaneously, package unit has taken into account guard time, conducting electric current ability, switch that operating voltage is low and the low-impedance requirement of transformer neutral point.
Description
Technical field
The utility model relates to a kind of power transformer neutral point direct current isolating devices, and in particular to one kind is based on injection etc.
The transformer neutral point DC isolation device of gas ions trigger switch.
Background technique
With the development of China's power industry and urban construction, the engineerings such as direct current transportation, high-speed railway and subterranean railway rule
Mould increasingly increases.DC transmission engineering is there are the monopole the earth method of operation, and larger DC current is using the earth as access.Subterranean railway
System is using rail as return flow path, and due to rail insulation against ground aging etc., DC current can be released into the earth.If in direct current
There are power transformers on current reflux path, then power transformer is possible to will receive the influence of DC current.Reason is
The access Equivalent DC impedance of the compositions such as power transformer, overhead line and cable is much smaller than the earth impedance.Due to power transformer
The closer core sataration point in operating point, if superposition DC current, can generate the offset of operating point, cause transformer abnormal vibration
Etc. failures.It is therefore desirable to carry out DC current isolation to the transformer for D.C. magnetic biasing occur.
There are three types of existing power transformer neutral point direct current isolating device basic principles, first is that utilizing capacitor " separated by direct communication "
Characteristic, in transformer neutral point series capacitance, such method can thoroughly completely cut off direct current；Second is that it is small to connect in transformer neutral point
Resistance, such method can only reduce DC current amplitude, and related with the factors such as system operational parameters, the earth impedance；Third is that
Transformer neutral point injects reverse current and offsets earth current, and such method control is complicated, and there are hysteresis effects.Therefore in transformation
Device neutral point series capacitance is a kind of preferably method.
Electric system is in addition to normal operating condition, it is also possible to the failures such as single-phase earthing occur, be for 220kV or more
System, it is desirable that transformer neutral point needs reliable metal to be grounded when single-phase fault occurs.By taking singlephase earth fault as an example, break down
Afterwards, it is uprushed, is quickly increased to from normal out-of-balance current (about 10A magnitude) thousands of by the zero-sequence current of transformer neutral point
Pacify electric current.According to neutral point series capacitance method, then greater impact electric current is likely to cause capacitor explosion damage, therefore needs
Will be in capacitor both ends parallel connection rapid protecting device, protective condenser that can be quick, stable when detecting the system failure, and
And the transient current handling capacity of claimed device is stronger.Routine techniques route is metallic contact protective switch and quickly protects
Protect the mode of switch in parallel protection.Since metallic contact protective switch conducting electric current is big, but actuation time is usually longer, usually
Up to several ms, fast protecting switch conducting electric current ability is weak, but actuation time is fast.Therefore failure occur when, usually first by
Fast protecting switch undertakes short circuit current early period, and after metallic contact protective switch is closed completely, short circuit current is transferred to gold
Attribute contact protection switch.
Patent " a kind of transformer neutral point condenser type blocking device earthed system " (application number: 104465050 A of CN) is situated between
Continued the protected mode of a kind of mechanical bypass switch and rectifier bridge series thyristor.Patent " a kind of transformer neutral point direct current every
Straight device " (grant number: 104810793 B of CN) using a kind of similar structures, difference is to buffer reactor position difference.
Patent " a kind of novel transformer neutral point capacitor blocking DC magnetic biasing suppression device " (grant number: 205051335 U of CN) uses
For the structure of double graphite gaps in parallel to replace thyristor branch, parallel connection gaps use the point being directly electrically connected with major loop
Firewire circle is lighted a fire.
In the prior art, more mature to metallic contact protective switch technology, usually vacuum circuit breaker, contactor etc.
Mature device, however for Primary Component-fast protecting switch in blocking device, the equal existing defects of current technology route.
It is needed using the scheme of thyristor so that the higher short circuit current of thyristor receiving, be easy to cause the damage of thyristor.Using double stones
The structure of black gap and the ignition coil being directly electrically connected with major loop introduces inductance, transformer in capacitance branch
The equivalent impedance ground of neutral point can increase, and be unsatisfactory for the requirement of the low impedance ground of neutral point.
Utility model content
The shortcomings that the purpose of the utility model is to overcome the above-mentioned prior arts provides a kind of based on jet plasma
The transformer neutral point DC isolation device of trigger switch, the device meet the requirement of centre-point earth impedance, are not present simultaneously
The problem of thyristor damages.
In order to achieve the above objectives, the transformer neutral point described in the utility model based on jet plasma trigger switch
DC isolation device include control and triggering system, the first earthing knife-switch, the second earthing knife-switch, based on the fast of jet plasma trigger switch
Fast protective switch, metallic contact protective switch, capacitance, for detect the voltage detector of capacitance two sides voltage with
And the current detector for detecting capacitance electric current, control and triggering system include control system and triggering system；
Power transformer is connected with one end of one end of the first earthing knife-switch and the second earthing knife-switch, another termination of the first earthing knife-switch
One end of ground, the other end of the second earthing knife-switch and the fast protecting switch based on jet plasma trigger switch, metallic contact
One end of protective switch and one end of capacitance are connected, the fast protecting switch based on jet plasma trigger switch
The other end of the other end, the other end of metallic contact protective switch and capacitance is grounded；
The output end and the output end of current detector and the input terminal of control system of voltage detector are connected, control system
The triggered system of the output end of system is connected with the control terminal of the fast protecting switch based on jet plasma trigger switch, control
The output end of system processed is connected with the control terminal of metallic contact protective switch.
Fast protecting switch based on jet plasma trigger switch include seal cavity, trigger electrode and be located at sealing
Intracorporal first main electrode of chamber, the second main electrode and high molecular polymer ablator block, the first main electrode are located at seal cavity
Side, the second main electrode is located at the other side of seal cavity, high molecular polymer ablator block be located at the second main electrode with
Between seal cavity inner wall, it is arranged fluted on high molecular polymer ablator block, is provided with through-hole in the second main electrode, it should
Through-hole is connected to form discharge cavity, first main electrode of discharge cavity face, one end of trigger electrode and triggering system with groove
It is connected, the other end of trigger electrode passes through high molecular polymer ablator block after being inserted in seal cavity and is inserted in discharge cavity
Interior, the first main electrode is connected with the second earthing knife-switch, the second main electrode ground connection.
The triggering system includes trigger controller, pulse voltage circuit and pulse current loop, wherein pulse voltage is returned
Road includes first diode, transformer, first capacitor and the first thyristor；Pulse current loop is opened including the second diode, magnetic
Pass, the second capacitor and the second thyristor；
One end of first capacitor is connected with the cathode of the anode of the first thyristor and first diode, the first thyristor
Cathode is connected with one end of transformer primary winding, the other end of transformer primary winding and the other end of first capacitor and
The anode of one diode is connected；
One end of second capacitor is connected with the cathode of the anode of the second thyristor and the second diode, the second thyristor
The anode of cathode and the second diode is connected with one end of magnetic switch, one end of transformer secondary winding and magnetic switch it is another
End and trigger electrode are connected, and the other end of transformer secondary winding, the other end of the second capacitor and the second main electrode are connected.
The trigger signal that trigger controller is sent to the first thyristor shifts to an earlier date in the trigger signal for being sent to the second thyristor,
Puncture the first thyristor with the high pressure trigger pulse for preventing pulse voltage circuit from exporting.
The utility model has the following beneficial effects:
Transformer neutral point DC isolation device described in the utility model based on jet plasma trigger switch exists
When specific operation, using the fast protecting switch based on jet plasma trigger switch, conducting electric current ability is strong, guard time
It is short, generally in Microsecond grade, avoid using caused by the power semiconductor devices such as thyristor the shortcomings that conducting electric current scarce capacity, and
Without the elements such as other inductance and resistance in entire circuit, guarantees the low impedance ground of transformer neutral point, so that it is met central point and connect
The requirement of ground impedance, and the problem of thyristor damages is not present, so that package unit has taken into account guard time, conducting electric current
Operating voltage is low and the low-impedance requirement of transformer neutral point for ability, switch.
Further, the first main electrode of discharge cavity face, so that the plasma that the first main electrode sprays directly sprays
Onto the first main electrode, directly run through gas gap, realizes that switch Microsecond grade is exceedingly fast conducting.
Further, in practical operation, the spacing between the first main electrode and the second main electrode can be increased, due to spray
The plasma of injection can directly run through gap, and service factor can be zero, and it is general that self discharge can be effectively reduced in biggish spacing
Rate, and can effectively reduce influence of internal field's distortion to switch self-breakdown voltage behind arc erosion surface.
Further, the second main electrode and trigger electrode are directly connected to realize under armed state for equipotential in the utility model
For trigger electrode without biasing Current Voltage, misleading of overcoming that trigger electrode in traditional structure needs that pre-applied DC voltage may cause is hidden
Suffer from.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the utility model；
Fig. 2 is the structural schematic diagram of the fast protecting switch 3 based on jet plasma trigger switch in the utility model；
Fig. 3 is the structural schematic diagram that system is triggered in the utility model.
Wherein, 1 be control and triggering system, 2 be metallic contact protective switch, 3 for based on jet plasma trigger
The fast protecting switch of switch, 4 for the first earthing knife-switch, 5 be the second earthing knife-switch, 6 be power transformer, 7 be voltage detector, 8 be electricity
Current sensor, 9 be seal cavity, 10 be the first main electrode, 11 be the second main electrode, 12 be high molecular polymer ablator
Block, 13 be trigger electrode, 14 be pulse voltage circuit, 15 be pulse current loop, 16 be magnetic switch, 17 be trigger controller.
Specific embodiment
The utility model is described in further detail with reference to the accompanying drawing:
With reference to Fig. 1, it is described in the utility model based on the transformer neutral point direct current of jet plasma trigger switch every
From device include control and triggering system 1, the first earthing knife-switch 4, the second earthing knife-switch 5, based on the quick of jet plasma trigger switch
Protective switch 3, metallic contact protective switch 2, capacitance C, the voltage detector for detecting the two sides capacitance C voltage
7 and the current detector 8 for detecting capacitance C electric current, control and triggering system 1 include control system and triggering system
System；Power transformer 6 is connected with one end of one end of the first earthing knife-switch 4 and the second earthing knife-switch 5, the other end ground connection of the first earthing knife-switch 4,
One end of the other end of second earthing knife-switch 5 and the fast protecting switch 3 based on jet plasma trigger switch, metallic contact are protected
One end of one end and capacitance C for protecting switch 2 is connected, the fast protecting switch 3 based on jet plasma trigger switch
The other end, the other end of metallic contact protective switch 2 and the other end of capacitance C be grounded；Voltage detector 7 it is defeated
The output end of outlet and current detector 8 is connected with the input terminal of control system, the triggered system of the output end of control system
It is connected with the control terminal of the fast protecting switch 3 based on jet plasma trigger switch, the output end and gold of control system
The control terminal of attribute contact protection switch 2 is connected.
With reference to Fig. 2, the fast protecting switch 3 based on jet plasma trigger switch includes seal cavity 9, trigger electrode 13
And the first main electrode 10, the second main electrode 11 and high molecular polymer ablator block 12 in seal cavity 9, first
Main electrode 10 is located at the side of seal cavity 9, and the second main electrode 11 is located at the other side of seal cavity 9, and high molecular polymer is burnt
Corrosion material block 12 is arranged on high molecular polymer ablator block 12 between 9 inner wall of the second main electrode 11 and seal cavity
It is fluted, it is provided with through-hole in the second main electrode 11, which is connected to form discharge cavity, the discharge cavity face with groove
One end of first main electrode 10, trigger electrode 13 is connected with triggering system, and the other end of trigger electrode 13 is inserted in seal cavity 9
High molecular polymer ablator block 12 is passed through afterwards to be inserted in discharge cavity, the first main electrode 10 is connected with the second earthing knife-switch 5, the
Two main electrodes 11 ground connection.
With reference to Fig. 3, the triggering system includes trigger controller 17, pulse voltage circuit 14 and pulse current loop 15,
Wherein, pulse voltage circuit 14 includes first diode D1, transformer T, first capacitor C1 and the first thyristor C3；Pulse current
Circuit 15 includes the second diode D2, magnetic switch 16, the second capacitor C2 and the second thyristor C4；One end of first capacitor C1 and the
The anode of one thyristor C3 and the cathode of first diode D1 are connected, the cathode of the first thyristor C3 and transformer T primary side around
One end of group is connected, and the other end of transformer T primary side winding and the other end of first capacitor C1 and first diode D1 are just
Pole is connected；One end of second capacitor C2 is connected with the cathode of the anode of the second thyristor C4 and the second diode D2, and second
The anode of the cathode of thyristor C4 and the second diode D2 are connected with one end of magnetic switch 16, and the one of transformer T vice-side winding
End be connected with the other end of magnetic switch 16 and trigger electrode 13, the other end of transformer T vice-side winding, the second capacitor C2 it is another
End and the second main electrode 11 are connected.
The utility model concrete principle are as follows:
Switching capacitance C when normal operation, it is directly complete by metallic contact protective switch 2 according to predetermined control strategy
Capacitance C, such as singlephase earth fault, zero-sequence current rapid increase, first system detection are promptly cut off when at, the system failure
To capacitance C voltage be more than predetermined upper threshold value or capacitance C electric current is more than upper limit threshold, and control system triggers metallicity
Contact protection switch 2 is begun to turn on, it is general it is fully on need to about several ms, while based on jet plasma trigger switch
The fast conducting within the Microsecond grade time of fast protecting switch 3 realizes the quick protection of capacitance C, thus by failure zero sequence electricity
Flow the branch road where being transferred to the fast protecting switch 3 based on jet plasma trigger switch from capacitance C；Work as metal
Property contact protection switch 2 be closed completely after, failure zero-sequence current is opened from the quick protection based on jet plasma trigger switch
3 are closed to be transferred on metallic contact protective switch 2；After fault current disappears, based on the fast of jet plasma trigger switch
Fast protective switch 3 can cease arc automatically, can put into capacitance C again after Awaiting Overhaul personnel inspection.
The concrete operating principle of fast protecting switch 3 based on jet plasma trigger switch are as follows:
Seal cavity 9 can be made of insulating materials such as organic glass or polycarbonate, after receiving triggering and conducting order,
Pulse voltage circuit 14 generates tens of kilovolts of high-voltage pulses first, forms 13-high molecular polymer of trigger electrode ablator block
Edge flashing between 12-the second main electrode, 11 three, but since 14 energy storage of pulse voltage circuit is less, it is only capable of forming light current
From channel, a large amount of plasmas can not be formed；It is delayed when by default, pulse current loop 15 forms weak to edge flashing
Ionic plasma channel and injected pulse high current form a large amount of plasmas, and plasma channel rapidly develops expansion, to height
12 surface of Molecularly Imprinted Polymer ablator block carries out ablation, generates a large amount of plasmas, and in air pressure rising, temperature increases and electromagnetism
Plasma is sprayed from discharge cavity under the comprehensive functions such as stress, is injected directly in the first main electrode 10, perforation the rapidly of discharging
Two main electrodes 11 and the first main electrode 10, complete the turn on process of gas switch.
The course of work of triggering system are as follows: trigger controller 17 issues trigger signal after receiving external command, wherein send
Trigger signal to pulse current loop 15 in the trigger signal for being sent to pulse voltage circuit 14, such as time interval is in advance
2us, in advance the second thyristor C4 conducting in trigger pulse current loop 15, the high pressure touching for preventing pulse voltage circuit 14 from exporting
Send out the first thyristor of pulse breakdown C3；The high-voltage nanosecond pulse that pulse voltage circuit 14 generates acts on trigger electrode 13, causes
Edge flashing, while the magnetic switch 16 in pulse current loop 15 can effectively undertake most pulse voltages；When by presetting
Between, the magnetic switch 16 in pulse current loop 15 is saturated, and pulse current loop 15 exports high current, high molecular polymer ablation material
Expect that 12 surface of block forms plasma, and spray discharge cavity, completes the trigger process of gas switch.In pulse voltage circuit 14
The capacitance of one capacitor C1 is less than the second capacitor C2 in pulse current loop 15, and first capacitor C1 and the second capacitor C2 can be adopted
With external power supply, or by the way of block capacitor commutation supply voltage, wherein the charging of first capacitor C1 and the second capacitor C2
Module is preferentially supplied power with double circuit and is combined using station electricity consumption and battery.
Claims (4)
1. a kind of transformer neutral point DC isolation device based on jet plasma trigger switch, which is characterized in that including
Control and triggering system (1), the first earthing knife-switch (4), the second earthing knife-switch (5), the quick protection based on jet plasma trigger switch
Switch (3), metallic contact protective switch (2), capacitance (C), the voltage for detecting the two sides capacitance (C) voltage are examined
Device (7) and the current detector (8) for detecting capacitance (C) electric current are surveyed, control and triggering system (1) include control system
System and triggering system；
Power transformer (6) is connected with one end of one end of the first earthing knife-switch (4) and the second earthing knife-switch (5), the first earthing knife-switch (4) it is another
One end ground connection, the one of the other end of the second earthing knife-switch (5) and the fast protecting switch (3) based on jet plasma trigger switch
The one end at end, one end of metallic contact protective switch (2) and capacitance (C) is connected, and is triggered based on jet plasma
The other end of the fast protecting switch (3) of switch, the other end of metallic contact protective switch (2) and capacitance (C) it is another
One end is grounded；
The output end of voltage detector (7) and the output end of current detector (8) are connected with the input terminal of control system, control
The triggered system of the output end of system is connected with the control terminal of the fast protecting switch (3) based on jet plasma trigger switch
It connects, the output end of control system is connected with the control terminal of metallic contact protective switch (2).
2. the transformer neutral point DC isolation device according to claim 1 based on jet plasma trigger switch,
It is characterized in that, the fast protecting switch (3) based on jet plasma trigger switch includes seal cavity (9), trigger electrode
(13) and be located at seal cavity (9) in the first main electrode (10), the second main electrode (11) and high molecular polymer ablation material
Expect block (12), the first main electrode (10) is located at the side of seal cavity (9), and the second main electrode (11) is located at seal cavity (9)
The other side, high molecular polymer ablator block (12) are located between the second main electrode (11) and seal cavity (9) inner wall, high score
It is arranged fluted on sub- polymer ablator block (12), the second main electrode is provided with through-hole on (11), the through-hole and groove phase
To form discharge cavity, one end of first main electrode of discharge cavity face (10), trigger electrode (13) is connected with triggering system for connection
It connects, the other end of trigger electrode (13) passes through high molecular polymer ablator block (12) after being inserted in seal cavity (9) and is inserted into
In in discharge cavity, the first main electrode (10) is connected with the second earthing knife-switch (5), the second main electrode (11) ground connection.
3. the transformer neutral point DC isolation device according to claim 1 based on jet plasma trigger switch,
It is characterized in that, the triggering system includes trigger controller (17), pulse voltage circuit (14) and pulse current loop (15),
Wherein, pulse voltage circuit (14) include first diode (D1), transformer (T), first capacitor (C1) and the first thyristor
(C3)；Pulse current loop (15) includes the second diode (D2), magnetic switch (16), the second capacitor (C2) and the second thyristor
(C4)；
One end of first capacitor (C1) is connected with the cathode of the anode of the first thyristor (C3) and first diode (D1), and first
The cathode of thyristor (C3) is connected with one end of transformer (T) primary side winding, the other end of transformer (T) primary side winding and
The other end of one capacitor (C1) and the anode of first diode (D1) are connected；
One end of second capacitor (C2) is connected with the cathode of the anode of the second thyristor (C4) and the second diode (D2), and second
The cathode of thyristor (C4) and the anode of the second diode (D2) are connected with one end of magnetic switch (16), transformer (T) pair side
One end of winding is connected with the other end of magnetic switch (16) and trigger electrode (13), the other end of transformer (T) vice-side winding,
The other end and the second main electrode (11) of two capacitors (C2) are connected.
4. the transformer neutral point DC isolation device according to claim 3 based on jet plasma trigger switch,
It is characterized in that, trigger controller (17) is sent to the trigger signal of the first thyristor (C3) in advance in being sent to the second thyristor
(C4) trigger signal, with the high pressure trigger pulse breakdown the first thyristor (C3) for preventing pulse voltage circuit from exporting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822079546.7U CN209029909U (en) | 2018-12-11 | 2018-12-11 | Transformer neutral point DC isolation device based on jet plasma trigger switch |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822079546.7U CN209029909U (en) | 2018-12-11 | 2018-12-11 | Transformer neutral point DC isolation device based on jet plasma trigger switch |
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| Publication Number | Publication Date |
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| CN209029909U true CN209029909U (en) | 2019-06-25 |
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ID=66911047
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109378798A (en) * | 2018-12-11 | 2019-02-22 | 西安交通大学 | Transformer neutral point DC isolation device based on jet plasma trigger switch |
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2018
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109378798A (en) * | 2018-12-11 | 2019-02-22 | 西安交通大学 | Transformer neutral point DC isolation device based on jet plasma trigger switch |
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