CN205489519U

CN205489519U - High -power direct current breaker of high voltage

Info

Publication number: CN205489519U
Application number: CN201620083561.7U
Authority: CN
Inventors: 张健
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-01-27
Filing date: 2016-01-27
Publication date: 2016-08-17
Anticipated expiration: 2026-01-27

Abstract

The utility model relates to a high -power direct current breaker of high voltage. The utility model discloses a quick, the safe powerful direct current of high voltage that cut -offs in the short time, furthest's simplification equipment structure reduces manufacturing cost simultaneously. The utility model provides a: the high -power direct current breaker of voltage, its characterized in that the circuit breaker includes major loop and first transfer return circuit and first the discharge return circuit parallelly connected with the major loop respectively, and the major loop is established ties by an alternating current circuit ware, quick section breaker subassembly, impedor and the 2nd alternating current circuit ware and is formed, it constitutes first transfer return circuit to connect in parallel with the major loop after being established ties with a change over switch by a capacitor bank spare, it constitutes the first return circuit of discharging to connect in parallel with a capacitor bank spare after being established ties with first discharge switch by a discharge resistance. The utility model is suitable for a high -tension transmission engineering technical field.

Description

High-tension high-power dc circuit breaker

Technical field

The present utility model relates to a kind of high-tension high-power dc circuit breaker.Belong to high voltage power transmission engineering skill Art field.

Background technology

At present, D.C. high voltage transmission or Multi-end flexible direct current transmission are more and more subject to owing to having bigger advantage The attention of people.D.C. high voltage transmission, owing to not having the reactive loss of circuit, efficiency of transmission high, works as power transmission line Road length only has HVDC Transmission Technology could be competent at long-distance transmissions requirement when exceeding certain distance.

Dc circuit breaker is one of visual plant of extra-high voltage direct-current transmission engineering current conversion station, and its Main Function is Change the method for operation of straight-flow system, remove the short trouble that DC side occurs.

Along with new forms of energy strategy development, large quantities of new energy power station are set up in succession, but the one of new forms of energy is big Feature is poor stability, and flexible DC power transmission can just solve the problem of poor stability in new-energy grid-connected, and And can be networked by the development soft straight transmission system of multiterminal.The development jumbo DC transmission system of multiterminal, just Must there is high voltage DC breaker, to ensure the security and stability of system.But owing to DC loop does not has electricity Flow through zero point, it is impossible to directly arc extinguishing, so existing dc circuit breaker going out mainly by AC circuit breaker Arc actuator, or produce zero crossing artificially by increasing resonance device, then carried out by bypass circuit Shunt the arc extinguishing condition produced with offer zero current.

With exchange arc quenching system compared with, DC current owing to not having " natural zero-crossing point " to be difficult to cut-off, Particularly under high voltage, big current condition, this problem is more acute.Additionally, direct-current short circuit electric current rises Speed is fast, it is desirable to cut-off in the time of several milliseconds after short circuit occurs.Therefore, high voltage, big electric current Under the conditions of the quick-speed turning on-off technology of DC current and corresponding high voltage DC breaker become restriction direct current network The Main Bottleneck problem of development, is also the most current study hotspot.

The composition structure & working mechanism of the dc circuit breaker of prior art is as it is shown in figure 1, with active type direct current As a example by circuit breaker trip DC current.

Active type dc circuit breaker typically by SF6 chopper (fracture) B, a capacitor C, one Spark gap R, and a reactor L and disconnecting switch S1 and a DC charging device Udc composition.First By charging device Udc, capacitor C is pre-charged to certain DC voltage.It is separated at chopper B contact After the suitable moment, disconnecting switch S1 of closing, preliminary filling excessively electricity capacitor jump to, on chopper, excite Oscillating current, it is achieved breaker fracture current over-zero, the principle process of arc extinction between fracture.But it is this Dc circuit breaker is except structure is excessively complicated, in addition to cost height, often it also occur that the phenomenon of not starting of oscillation, sternly Heavily constrain stability and the economic benefit thereof of HVDC transmission system.

Summary of the invention

The technical problems to be solved in the utility model is: provide a kind of high-tension high-power dc circuit breaker, main Syllabus is the quickest, the safe DC current cut-offfing high-tension high-power, maximum limit simultaneously The simplification device structure of degree, reduces manufacturing cost.

This utility model the technical scheme is that high-tension high-power dc circuit breaker, it is characterised in that Described chopper includes that major loop and the first commutating circuit and first in parallel with major loop respectively discharge back Road, major loop is by the first AC circuit breaker, quick section breaker assembly, impedor and the second AC circuit breaker It is in series；First turn is constituted by parallel with major loop after the first capacitor assembly and the first switching switch series connection Retract road；In parallel with the first capacitor assembly after being connected by the first discharge resistance and the first discharge switch constitute the One discharge loop.

Described major loop is also parallel with the second commutating circuit and the second discharge loop, described second commutating circuit by Being formed in parallel with major loop after second capacitor assembly and the second switching switch series connection, described second discharges back again It is formed in parallel with the second capacitor assembly again after routeing the second discharge resistance and the series connection of the second discharge switch.

The end electric capacity two of described first capacitor assembly is terminated with sampling the first voltage sampling electricity of DC voltage Road；The end electric capacity two of the second capacitor assembly is terminated with sampling the second voltage sample circuit of DC voltage.

Described quick section breaker assembly is formed by a quick AC circuit breaker and capacitor in parallel.

Described impedor is made up of winding and the iron core with magnetic closed-loop path.

Described first voltage sample circuit is made up of the first voltage transformer and the first voltage relay, and this is first years old Voltage transformer includes iron core I and iron core II, and two corresponding primary windings are identical and connect, two Individual secondary coil is identical and anti-phase series connection, and the sampling voltage at sampling capacitor two ends is followed by through bridge rectifier On the first voltage relay；This first voltage relay has the first normally opened contact of the first voltage relay The second normally opened contact with the first voltage relay.

The structure of described second voltage sample circuit and the first voltage sample circuit is identical, and the second voltage takes Sample circuit is made up of the second voltage transformer and the second voltage relay, and this second voltage transformer includes iron core I and iron core II, two corresponding primary windings are identical and connect, and two secondary coils are identical And anti-phase series connection, the sampling voltage at sampling capacitor two ends is followed by the second voltage relay through bridge rectifier； This second voltage relay has the first normally opened contact of the second voltage relay and the of the second voltage relay Two normally opened contacts.

The beneficial effects of the utility model are: this utility model make use of the principle that energy shifts, and solves A difficult problem for quick-speed turning on-off DC current under high voltage, big current condition, the most also When being short trouble generation, it can be cut-off safely within the time of several milliseconds by this utility model.Additionally, This utility model simplifies the excessively complicated equipment of employing at present, directly reduces manufacturing cost, at new energy Source strategy fast development instantly, has positive economic benefit and social meaning.

Accompanying drawing explanation

Fig. 1 is the circuit diagram of this utility model background technology.

Fig. 2 is the circuit diagram of primary equipment in this utility model embodiment one.

Fig. 3 is the circuit diagram of primary equipment in this utility model embodiment two.

Fig. 4-1, Fig. 4-2 are the circuit diagram of secondary device in embodiment one respectively and go out line chart.

Fig. 5 is the electrical secondary system sequence control principle figure of embodiment one.

Fig. 6 is the separating brake process schematic of the AC circuit breaker of band opening and closing resistor.

Detailed description of the invention

Embodiment one,

As in figure 2 it is shown, the present embodiment high-tension high-power dc circuit breaker, including major loop and respectively with The first commutating circuit that major loop is in parallel and the first discharge loop, major loop by the first AC circuit breaker 1DL, Quickly section breaker assembly K, impedor L and the second AC circuit breaker 2DL are in series；By the first electric capacity Device assembly C₁With the first switching switch QK₁In parallel with major loop again after series connection constitute the first commutating circuit；By One discharge resistance R₁With the first discharge switch FK₁With the first capacitor assembly C after series connection₁Composition first in parallel is put Electricity loop.

Described first AC circuit breaker 1DL and the second AC circuit breaker 2DL is that two AC type routines are lithium Sulfur (SF6) chopper, electric pressure and DC voltage match (such as 500KV).Can also be by double-fracture AC circuit breaker two fractures are controlled switch off time by operating mechanism respectively, and carry out series wiring.Also The turned off high-power electronic switch that corresponding voltage is mated can be selected, as GTO, IGBT etc. can realize big electricity Stream, high voltage cut-off the equipment of function.

Described quick section breaker assembly K is formed in parallel by a quick AC circuit breaker KK and resistor R, Quickly AC circuit breaker KK is SF6 AC circuit breaker or vacuum circuit breaker, when running at ordinary times, electric current from KK flows through, and power consumption is almost nil, when load current or short circuit current are cut-off by needs, by controlling electricity Road first disconnects KK, and switch off time, typically within 5ms, forces electric current to flow through from resistor R, produces Voltage drop Δ U_R.Resistor R is the carborundum resistor of resistance R=5～25 Ω, and resistance value is unsuitable excessive, no Then can affect the normal arc extinguishing of high-speed switch, but can not be too small, otherwise cannot realize electric current to capacitor assembly The purpose of transfer.

If when selecting the first AC circuit breaker 1DL, select the double-fracture of a kind of referred to as band switching-on resistance During chopper, its function is the same with the quick section breaker assembly K of installation, at this moment can omit and quickly divide Disconnected switch module K.Double-fracture chopper (500KV) model of common band switching-on resistance has: Xi'an high pressure Switchgear plant raw LW-13-500, or LW6-500 type.

Described impedor L is made up of winding and the iron core with magnetic closed-loop path, and winding can use iron wire, copper Silk or aluminum steel body, iron core is that silicon (silicon) steel disc builds up or the soft magnetic materials of non-crystaline amorphous metal.This example hinders Anti-device L plays and passes through in the short-circuit statePrinciple obtain a voltage drop.

Described first switching switch QK₁There is the first auxiliary contact QK of the first switching switch₁-Wb₁With first Second auxiliary contact QK of switching switch₁-Wb₂。

Described first discharge switch FK₁For with the first capacitor assembly C₁The vacuum hexafluoro that electric pressure matches Change sulfur chopper.First discharge resistance R₁For carborundum resistor.

As shown in Fig. 4-1, Fig. 4-2, described first capacitor assembly C₁End electric capacity two be terminated with sampling First voltage sample circuit of DC voltage.This first voltage sample circuit by the first voltage transformer 1YB and First voltage relay 1YJ composition.Described first voltage transformer 1YB includes iron core I and iron core II, right Two primary windings answered are identical and connect, and two secondary coils are identical and anti-phase series connection, take Sample electric capacity C₁₀₁The sampling voltage at two ends is followed by the first voltage relay 1YJ through bridge rectifier；This is first years old Voltage relay 1YJ has the first normally opened contact 1YJK of the first voltage relay₁With the first voltage relay The second normally opened contact 1YJK₂。

The operation principle of the present embodiment one and work process are following (seeing Fig. 2):

Time properly functioning, the first AC circuit breaker 1DL and the second AC circuit breaker 2DL all closes operation, the One switching switch QK₁Closing position.Owing to impedor L is under DC current, its impedance presents substantially zeroed, The series connection of i.e. impedor L accesses, almost on DC line transmission of electricity not impact.Impedor L resistance value is by defeated 5/10000ths losses sending power design resistance.

When being short-circuited on circuit, such as D₂Point short circuit, by bus to short dot D₂Conveying short circuit current I_D, I_DRespectively flow through the first AC circuit breaker 1DL, quick section breaker assembly K, impedor L and the second exchange Chopper 2DL, when short circuit current flows through impedor L, owing to increasing suddenly when electric current compares load condition About 20～30 times, the voltage drop on impedor L is made also to be greatly improved at transcient short circuit time, according to electromagnetic induction Principle and impedor L internal resistance R_LImpact, impedor L can induce about 20～30 times straight Stream component of voltage Δ U_L, due to Δ U_LRaise reason, force short circuit current by major loop to the first capacitor Assembly C₁First commutating circuit transfer, i.e. can be to the first capacitor assembly C₁Charging, if C₁Capacity Design sufficiently large, short circuit current I_DTo C₁Charging take around time of 15-25ms.Charged at this Journey flows through the electric current on major loop the least, first will be fast by the self-con-tained unit of relay protection in power system Speed AC circuit breaker KK disconnects, and forces short circuit current to flow to resistor R, i.e. produces voltage drop Δ U_R, now Magnitude of voltage U₁=Δ U_L+ΔU_RWill be bigger, more electric current again shifts and flows to the first capacitor assembly C₁, The most just can cut-off the first AC circuit breaker 1DL by self-con-tained unit, owing to having flow through the electric current of 1DL The least, electric arc will quickly extinguish.Work as C₁When being full of, the electric current on major loop still keeps low discharge, the most again The second AC circuit breaker 2DL the most no longer difficulty is cut-off by self-con-tained unit.

When needs cut off load current, first quick AC circuit breaker KK is cut-off, design resistor R's Resistance is 10～30 Ω, if now load current is that after 3000A, KK disconnect, R is upper will present 3000A The magnitude of voltage of × 10 Ω=30KV, this voltage will make load current Ie to the first capacitor assembly C1 charging Flow in first commutating circuit of the first capacitor assembly C1, the most just can pass through order controller, by One AC circuit breaker 1DL disconnects.Owing to now electric current transfer flows to the first capacitor assembly C1, on major loop Electric current is the least, and therefore the first AC circuit breaker 1DL is easy to cut-off.

In design of the present utility model, trip switch off time T by the first AC circuit breaker 1DL₁Less than first Capacitor assembly C₁C when charging interval Tc, that is 1DL tripping₁Charging voltage be still not up to full of complete The state of volume voltage, and work as C₁After being full of voltage, by the first voltage transformer 1YB of the first voltage sample circuit To the first voltage relay 1YJ output voltage signal, to start the second AC circuit breaker 2DL continuation separating brake. Now, due to the first capacitor assembly C₁Both end voltage it has been established that when to C₁Charge to close to specified During voltage so that the electric current flowing through the second AC circuit breaker 2DL is almost nil, i.e. extinguishes this direct-current arc also It is easy.

This programme takes full advantage of the moment at the big electric current of direct-current short circuit, impedor L coil the anti-magnetic produced Gesture changes,And the DC component produced on resistor RElectric current is forced to occur Principle to capacitor assembly transfer, it is achieved that chopper cut-offs under small area analysis state, makes at present may be used The chopper bought can operate a switch in the case of high voltage, big (direct current) electric current without consider arcing and The problem of arc extinguishing difficulty.

Embodiment two,

As shown in Fig. 3, Fig. 4, Fig. 5, this example is also parallel with the second commutating circuit and the second electric discharge at major loop Loop, described second commutating circuit is by the second capacitor assembly C₂With the second switching switch QK₂After series connection again with Major loop is formed in parallel, and described second discharge loop is by the second discharge resistance R₂With the second discharge switch FK₂String After connection again with the second capacitor assembly C₂It is formed in parallel.

Described first capacitor assembly C₁End electric capacity two be terminated with sample DC voltage the first voltage sampling Circuit；Second capacitor assembly C₂End electric capacity two be terminated with sample DC voltage second voltage sampling electricity Road.

The structure of described second voltage sample circuit and the first voltage sample circuit is identical, this second voltage Sample circuit is made up of the second voltage transformer 2YB and the second voltage relay 2YJ, this second mutual induction of voltage Device 2YB includes iron core I and iron core II, and two corresponding primary windings are identical and connect, two two Secondary coil is identical and anti-phase series connection, sampling capacitor C₁₀₁The sampling voltage at two ends is followed by through bridge rectifier On second voltage relay 2YJ；It is first normal that this second voltage relay 2YJ has the second voltage relay Open contact 2YJK₁The second normally opened contact 2YJK with the second voltage relay₂。

In Practical Project, transmission line of electricity has reclosing requirement, i.e. for the first AC circuit breaker 1DL Have with the second AC circuit breaker 2DL again close a floodgate, the requirement of separating brake, i.e. when circuit for the first time fault, 1DL, 2DL all disconnect, and now, short circuit current is to the first capacitor assembly C₁After charging, still have a large amount of Electric energy is stored in C₁On, for completing the task of circuit re-switching, it is necessary to first by C₁Excise with mains side, the most disconnected Open the first switching switch QK₁, close the first discharge switch FK simultaneously₁, force C₁Discharge.Same with this Time, under the cooperation of control circuit, close the second switching switch QK₂, make the second commutating circuit and second put Electricity loop is proceeded to duty by resting state.

The work process of the present embodiment two is described as follows:

After the first AC circuit breaker 1DL trips, grid short circuit electric current I_DTo the first capacitor assembly C₁Fill Electricity, at elapsed time T_CAfter Chong Maning, it is positioned at the first capacitor assembly C₁First voltage transformer 1YB of end The coil band making the first voltage relay 1YJ electrically activates and makes the first normally opened contact 1YJK therein₁Guan Bi, makes Second AC circuit breaker 2DL trips, and makes again the second normally opened contact 1YJK of the first voltage relay₂Close Close, make the first switching switch QK₁Tripping operation；Meanwhile, by the first switching switch QK₁In operating mechanism The first auxiliary contact QK₁-Wb₁At QK₁After separating brake, it is also turned on the first discharge switch FK₁Closing line Circle, makes the first capacitor assembly C₁Start electric discharge.First switching switch QK₁The second auxiliary contact QK₁-Wb₂ Connect the second switching switch QK again₂Closing coil QK₂-HQ, passes through QK₂By the second capacitor assembly C₂ Duty is proceeded to by resting state.

After above action completes, reclosing device (carrying in electric control system) makes 1DL, 2DL respectively Again close a floodgate, now the first capacitor assembly C₁Have dropped out, by the second capacitor assembly C₂Take over operation, if Run into permanent fault on circuit, then repeat the sequential process of trip operation for the first time.

When after 1DL, 2DL again disjunction, can be by the pre-designed sequence circuit of computer system Disconnect the second switching switch QK again₂, close the second discharge switch FK₂, make the second capacitor assembly C₂Enter Discharge condition.

In automatic control circuit designs, above-mentioned C₁、C₂、QK₁、QK₂Carry out samsara switching, to ensure When 1DL action separating brake, a group capacitor is always had to be in no-voltage state to be filled, to realize short circuit current I_DThe purpose of orientation transfer.

The work process of the double-fracture chopper (AC circuit breaker) of band switching-on resistance it is shown that such as Fig. 6, During separating brake, main contact first disconnects, and switching-on resistance R₁₁Still in connection status, i.e. after main contact disconnection arc extinguishing, Again by switching-on resistance device R₁₁Seal in major loop.

Claims

1. a high-tension high-power dc circuit breaker, it is characterised in that: described chopper include major loop with And first commutating circuit in parallel with major loop and the first discharge loop respectively, major loop is by the first alternating current interruption Device (1DL), quick section breaker assembly (K), impedor (L) and the second AC circuit breaker (2DL) It is in series；By the first capacitor assembly (C₁) switch (QK with the first switching₁) after series connection with major loop Composition in parallel first commutating circuit；By the first discharge resistance (R₁) and the first discharge switch (FK₁) after series connection With the first capacitor assembly (C₁) composition in parallel first discharge loop.

High-tension high-power dc circuit breaker the most according to claim 1, it is characterised in that: described master Loop is also parallel with the second commutating circuit and the second discharge loop, and described second commutating circuit is by the second capacitor Assembly (C₂) switch (QK with the second switching₂) be formed in parallel with major loop again after series connection, described second puts Electricity loop is by the second discharge resistance (R₂) and the second discharge switch (FK₂) after series connection again with the second Capacitor banks Part (C₂) be formed in parallel.

High-tension high-power dc circuit breaker the most according to claim 1, it is characterised in that: described One capacitor assembly (C₁) end electric capacity two be terminated with sample DC voltage the first voltage sample circuit.

High-tension high-power dc circuit breaker the most according to claim 2, it is characterised in that: described One capacitor assembly (C₁) end electric capacity two be terminated with sample DC voltage the first voltage sample circuit； Second capacitor assembly (C₂) end electric capacity two be terminated with sample DC voltage the second voltage sample circuit.

5. according to the high-tension high-power dc circuit breaker described in claim 3 or 4, it is characterised in that: institute State quick section breaker assembly (K) in parallel by a quick AC circuit breaker (KK) and resistor (R) Form.

6. according to the high-tension high-power dc circuit breaker described in claim 3 or 4, it is characterised in that: institute State impedor (L) to be made up of winding and the iron core with magnetic closed-loop path.

High-tension high-power dc circuit breaker the most according to claim 3, it is characterised in that: described One voltage sample circuit is made up of the first voltage transformer (1YB) and the first voltage relay (1YJ), should First voltage transformer (1YB) includes iron core I and iron core II, and two corresponding primary windings are identical And connecting, two secondary coils are identical and anti-phase series connection, sampling capacitor (C₁₀₁) two ends sampling electricity Pressure is followed by the first voltage relay (1YJ) through bridge rectifier；This first voltage relay (1YJ) There is the first normally opened contact (1YJK of the first voltage relay₁) and the first voltage relay second normally opened touch Point (1YJK₂)。

High-tension high-power dc circuit breaker the most according to claim 4, it is characterised in that: described The structure of one voltage sample circuit and the second voltage sample circuit is identical, wherein,

First voltage sample circuit is by the first voltage transformer (1YB) and the first voltage relay (1YJ) group Becoming, this first voltage transformer (1YB) includes iron core I and iron core II, and two corresponding primary windings are complete Exactly the same and connect, two secondary coils are identical and anti-phase series connection, sampling capacitor (C₁₀₁) two ends Sampling voltage is followed by the first voltage relay (1YJ) through bridge rectifier；This first voltage relay (1YJ) there is the first normally opened contact (1YJK of the first voltage relay₁) and the of the first voltage relay Two normally opened contact (1YJK₂)；

Second voltage sample circuit is by the second voltage transformer (2YB) and the second voltage relay (2YJ) group Becoming, this second voltage transformer (2YB) includes iron core I and iron core II, and two corresponding primary windings are complete Exactly the same and connect, two secondary coils are identical and anti-phase series connection, sampling capacitor (C₁₀₁) two ends Sampling voltage is followed by the second voltage relay (2YJ) through bridge rectifier；This second voltage relay (2YJ) there is the first normally opened contact (2YJK of the second voltage relay₁) and the of the second voltage relay Two normally opened contact (2YJK₂)。