CN107769240A - The control method and device of direct current change-over switch - Google Patents

The control method and device of direct current change-over switch Download PDF

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Publication number
CN107769240A
CN107769240A CN201711025837.1A CN201711025837A CN107769240A CN 107769240 A CN107769240 A CN 107769240A CN 201711025837 A CN201711025837 A CN 201711025837A CN 107769240 A CN107769240 A CN 107769240A
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China
Prior art keywords
over switch
loop line
inverter side
change
line change
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CN201711025837.1A
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CN107769240B (en
Inventor
黄莹
郭龙
赵晓斌
卢毓欣
侯婷
李凌飞
辛清明
张祖安
徐迪臻
邱伟
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CSG Electric Power Research Institute
Research Institute of Southern Power Grid Co Ltd
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Research Institute of Southern Power Grid Co Ltd
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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
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Remote Monitoring And Control Of Power-Distribution Networks (AREA)

Abstract

The present invention relates to the control method and device of direct current change-over switch.Methods described includes：Three end straight-flow systems are controlled to enter the state from state shift the second loop line path of the first loop line path；The first loop line change-over switch of the first inverter side is controlled to close；Send first to other instruction change-over switches of inverter side simultaneously to forbid instructing, to prevent these direct current change-over switch malfunctions；The feedback signal that switch closure is completed is received, the second loop line change-over switch of the first inverter side of control disconnects；Receive the feedback signal for switching off completion, the first loop line change-over switch closure of the second inverter side of control；The feedback signal that switch closure is completed is received, the second loop line change-over switch of the second inverter side of control disconnects.Described device is device corresponding with the above method.The present invention can avoid three end straight-flow systems from occurring the electric current of inverter side one end in conversion operation mode filling to the situation of the other end, and then ensure that three end straight-flow systems can be run with security and stability in conversion operation mode.

Description

The control method and device of direct current change-over switch
Technical field
The present invention relates to technical field of direct current power transmission, more particularly to a kind of control method and dress of direct current change-over switch Put.
Background technology
Traditional both ends straight-flow system, one end are rectification side, and the other end is inverter side, and (the earth returns its direct current change-over switch Line change-over switch, Earth Return Transfer Breaker, ERTB and metallic return change-over switch, Metallic Return Transfer Breaker, MRTB) certain one end installed therein, when being operated to direct current change-over switch, operation Order is simple.But the operation for the direct current change-over switch of three end straight-flow systems is more complicated.The inverter side of three end straight-flow systems Two DC terminals have been accessed, to complete the conversion of system operation mode, need to install direct current change-over switch at the both ends of inverter side, Relative to two-terminal direct current transmission system, the increase of its direct current change-over switch quantity, the operation of direct current change-over switch also becomes more sophisticated, But existing direct current change-over switch control method, existing causes current conversion station to have high current to flow into grounded screen in station through ground return circuit Risk, to current conversion station run produce harmful effect, or even influence personal safety.
The content of the invention
Based on this, the invention provides the control method and device of direct current change-over switch, can guarantee that and are changing three end direct currents Three end straight-flow systems are run with security and stability during the method for operation of system.
The embodiment of the present invention includes：
A kind of control method of direct current change-over switch, including：
The signal of three end straight-flow systems of conversion is received, control enable signal, control described three are sent to three end straight-flow systems Straight-flow system is held to enter the state from state shift the second loop line path of the first loop line path；Wherein, the three ends direct current system System includes the first inverter side and the second inverter side, and the first inverter side, the second inverter side include the first loop line and the second loop line；
In the state of state shift the second loop line path that three end straight-flow systems enter from the first loop line path, to first First loop line change-over switch of inverter side sends the first close command, to control the conversion of the first loop line of first inverter side to open Close and close；Simultaneously to the second loop line change-over switch of the first inverter side, the first loop line change-over switch of the second inverter side, second time Line change-over switch, which sends first, to be forbidden instructing, to prevent the second loop line change-over switch of first inverter side, the second inverter side The first loop line change-over switch and the second loop line change-over switch malfunction；
The feedback signal that the first loop line change-over switch closure of the first inverter side is completed is received, to first inverter side Second loop line change-over switch sends the first open command, to control the second loop line change-over switch of first inverter side to disconnect；
The the second loop line change-over switch for receiving the first inverter side disconnects the feedback signal completed, to second inverter side First loop line change-over switch sends the second close command, to control the first loop line change-over switch of second inverter side to close；
The feedback signal that the first loop line change-over switch closure of the second inverter side is completed is received, to second inverter side Second loop line change-over switch sends the second open command, to control the second loop line change-over switch of second inverter side to disconnect.
A kind of control device of direct current change-over switch, including：
Control signal receiving module, for receiving the signal of three end straight-flow systems of conversion, control is sent to three end straight-flow systems Enable signal processed, control three end straight-flow system enter the shape from state shift the second loop line path of the first loop line path State；Wherein, three end straight-flow system includes the first inverter side and the second inverter side, and the first inverter side, the second inverter side are wrapped Containing the first loop line and the second loop line；
First switch control module, returned for entering in three end straight-flow systems from the state shift second of the first loop line path In the state of line path, the first close command is sent to the first loop line change-over switch of the first inverter side, to control described first The first loop line change-over switch closure of inverter side；Simultaneously to the second loop line change-over switch of the first inverter side, the second inverter side First loop line change-over switch, the second loop line change-over switch, which send first, to be forbidden instructing, to prevent the second of first inverter side Loop line change-over switch, the first loop line change-over switch of the second inverter side and the second loop line change-over switch malfunction；
Second switch control module, the feedback letter that the first loop line change-over switch closure for receiving the first inverter side is completed Number, the first open command is sent to the second loop line change-over switch of first inverter side, to control first inverter side Second loop line change-over switch disconnects；
3rd switch control module, the second loop line change-over switch for receiving the first inverter side disconnect the feedback letter completed Number, the second close command is sent to the first loop line change-over switch of second inverter side, to control second inverter side First loop line change-over switch closes；
And the 4th switch control module, what the first loop line change-over switch closure for receiving the second inverter side was completed Feedback signal, the second open command is sent to the second loop line change-over switch of second inverter side, it is described second inverse to control The the second loop line change-over switch for becoming side disconnects.
A kind of computer-readable recording medium, is stored thereon with computer program, and the program is realized when being executed by processor The step of method described above.
A kind of computer equipment, including memory, processor and storage can be run on a memory and on a processor Computer program, the step of realizing method described above during the computing device described program.
Above-mentioned technical proposal, when three end straight-flow systems need to turn to metallic return pattern from Ground return pattern, control System receives the signal of three end straight-flow systems of conversion, sends control enable signal to three end straight-flow systems, controls three end straight Streaming system enters the state from the state shift metallic return path of Ground return path；The ERTB of the first inverter side is closed, together When send forbid instructing, to prevent the ERTB of the first inverter side, ERTB, MRTB malfunction of the second inverter side；It is determined that the first inversion The MRTB for disconnecting the first inverter side is controlled again after the ERTB closures of side；It is determined that the MRTB of the first inverter side disconnects and controlled again afterwards The ERTB of system the second inverter side of closure；It is determined that last control disconnects the second inverter side after the ERTB closures of the second inverter side MRTB.This operating method, which effectively prevent the situation that d sides electric current pours in down a chimney x sides, to be occurred.When three end straight-flow systems are needed from metal When loop mode turns to Ground return pattern, its method of controlling switch is corresponding with the above method.According to turning for above-mentioned technical proposal Change switching operation three end straight-flow systems are opened or closed, the electric current that can avoid the occurrence of inverter side one end is filled to another The situation of one end, and then ensure that three end straight-flow systems can be transported with security and stability when changing the method for operation of three end straight-flow systems OK.
Brief description of the drawings
Fig. 1 is the indicative flowchart of the control method of direct current change-over switch in an embodiment；
Fig. 2 is the schematic diagram of three end straight-flow systems in an embodiment；
Fig. 3 is the equivalent circuit diagram of the direct current change-over switch of both ends straight-flow system in an embodiment；
Fig. 4 is the equivalent circuit diagram of the direct current change-over switch of three end straight-flow systems in an embodiment；
Fig. 5 is that three the second inverter sides of end straight-flow system are in metallic return path, the first inverter side is in an embodiment Equivalent circuit diagram under Ground return and metallic return path in parallel operating condition；
Fig. 6 (a) is equivalent before three the first inverter sides of end straight-flow system closure Ground return change-over switch in an embodiment Circuit diagram；
Fig. 6 (b) is equivalent after three the first inverter sides of end straight-flow system closure Ground return change-over switch in an embodiment Circuit diagram；
Fig. 6 (c) is equivalent after three the first inverter sides of end straight-flow system disconnection metallic return change-over switch in an embodiment Circuit diagram；
Fig. 6 (d) is equivalent after three the second inverter sides of end straight-flow system closure Ground return change-over switch in an embodiment Circuit diagram；
Fig. 6 (e) is equivalent after three the second inverter sides of end straight-flow system disconnection metallic return change-over switch in an embodiment Circuit diagram；
Fig. 7 is the structural representation of the control device of direct current change-over switch in an embodiment.
Embodiment
In order to make the purpose , technical scheme and advantage of the present invention be clearer, it is right below in conjunction with drawings and Examples The present invention is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, and It is not used in the restriction present invention.
Although the step in the present invention is arranged with label, it is not used to limit the precedence of step, unless It specify that the order of step or based on the execution of certain step needs other steps, otherwise the relative rank of step is It is adjustable.
The embodiment of the present invention provides a kind of control method of direct current change-over switch, and methods described includes step：Receive conversion The signal of three end straight-flow systems, control enable signals are sent to three end straight-flow systems, control three end straight-flow system enter from The state of state shift the second loop line path of first loop line path；Wherein, three end straight-flow system includes the first inverter side With the second inverter side, the first inverter side, the second inverter side include the first loop line and the second loop line；Enter in three end straight-flow systems In the state of state shift the second loop line path of the first loop line path, sent out to the first loop line change-over switch of the first inverter side The first close command is sent, to control the first loop line change-over switch of first inverter side to close；Simultaneously to the first inverter side Second loop line change-over switch, the first loop line change-over switch of the second inverter side, the second loop line change-over switch, which send first, to be forbidden referring to Order, to prevent the second loop line change-over switch of first inverter side, the first loop line change-over switch of the second inverter side and the Two loop line change-over switch malfunctions；The feedback signal that the first loop line change-over switch closure of the first inverter side is completed is received, to described Second loop line change-over switch of the first inverter side sends the first open command, to control the second loop line of first inverter side to turn Change and switch off；The the second loop line change-over switch for receiving the first inverter side disconnects the feedback signal completed, to second inversion First loop line change-over switch of side sends the second close command, to control the first loop line change-over switch of second inverter side to close Close；The feedback signal that the first loop line change-over switch closure of the second inverter side is completed is received, to the second of second inverter side Loop line change-over switch sends the second open command, to control the second loop line change-over switch of second inverter side to disconnect.This hair Bright embodiment also provides the control device of corresponding direct current change-over switch.It is described in detail individually below.
As shown in figure 1, the indicative flowchart of the control method for the direct current change-over switch of an embodiment.The embodiment The control method of the direct current change-over switch of offer mainly includes step S110 to step S150, describes in detail as follows：
S110, the signal for receiving three end straight-flow systems of conversion, control enable signal is sent to three end straight-flow systems, controls institute Three end straight-flow systems are stated into the state of state shift the second loop line path from the first loop line path；Wherein, three end is straight Streaming system includes the first inverter side and the second inverter side, and the first inverter side, the second inverter side include the first loop line and second time Line.
Generally for DC transmission system, include positive and negative polarities per one end (each rectification side and inverter side), it is each Pole is all connected by being grounded polar curve with the earth, and is connected between polar curve and polar curve by switch.Monopolar ground return refers to, direct current The often end of transmission system all only has a pole to put into operation, and forms loop by the earth.Monopolar metallic return refers to that direct current is defeated The often end of electric system all only has a pole to put into operation, and (such a by the switching circuitry formation loop between polar curve and polar curve State lower switch is in closure state).The often end ground electrode circuit of DC transmission system is generally being stood outside outer certain distance, is passed through Special circuit extends and buried to big ground depths, this mode ground electrode circuit ground connection；In addition, often end is also needed to every In current conversion station where holding, in provided underground grounded screen, as the standby of ground electrode circuit ground connection, so as to ground electrode circuit failure Or as temporary grounding when needing to overhaul.
Broken down in DC transmission system, it is necessary to, it is necessary to which the Ground return of DC transmission system is turned during trouble hunting For metallic return, metallic return is switched into Ground return again after overhauling well.Alternatively, the state from the first loop line path Turn to the second loop line path state refer to the monopole the earth method of operation be converted to the monopole metal method of operation or monopole metal operation Mode is converted to the monopole the earth method of operation, in other words, and from Ground return patten transformation be metallic return pattern or from gold Category loop mode is converted to Ground return pattern.
In the present invention, the first inverter side and two inverter sides that the second inverter side is three end straight-flow systems, from greatly When loop line turns metallic return, the first inverter side is designated as x ends, and the second inverter side is designated as d ends；Corresponding, turn from metallic return During Ground return, the first inverter side is designated as d ends, and the second inverter side is designated as x ends.
The schematic diagram of three end straight-flow systems (three end DC transmission systems) is as shown in Figure 2.(both ends are straight for both ends straight-flow system Stream transmission system) include rectification side and inverter side (as shown in Figure 3), and three end straight-flow systems are different from both ends straight-flow system, such as Shown in Fig. 2, it has accessed two DC terminals, respectively the first inverter side 220 and the second inverter side 230 in inverter side, and first is inverse Become the inverter side 230 of side 220 and second and include metallic return and Ground return.In polar curve in the current conversion station of first inverter side 220 It is connected with drawing a circuit on neutral bus respectively with the second inverter side 230.Wherein, NBS refers to neutral bus switch (Neutral Bus Switch), NBGS refer to neutral bus earthed switch (Neutral Bus Grounding Switch).
In this step, after control system receives the signal of three end straight-flow systems of conversion, sent to three end straight-flow systems Enable signal is controlled, control three end straight-flow system enters the shape from state shift the second loop line path of the first loop line path State.
S120, in the state of three end straight-flow systems enter state shift the second loop line path from the first loop line path, The first close command is sent to the first loop line change-over switch of the first inverter side, to control the first loop line of first inverter side Change-over switch closes；Simultaneously to the second loop line change-over switch of the first inverter side, the second inverter side the first loop line change-over switch, Second loop line change-over switch, which sends first, to be forbidden instructing, to prevent the second loop line change-over switch of first inverter side, second First loop line change-over switch of inverter side and the second loop line change-over switch malfunction.
In the case that three end straight-flow systems enter transition status, start to control the opening and closing of direct current change-over switch, realize direct current The conversion of the method for operation of transmission system.This step control system controls the first loop line change-over switch closure of the first inverter side； Sending simultaneously forbids instruction to control other direct current change-over switches of inverter side, prevents their malfunctions.
S130, the feedback signal that the first loop line change-over switch closure of the first inverter side is completed is received, it is inverse to described first The the second loop line change-over switch for becoming side sends the first open command, to control the second loop line change-over switch of first inverter side Disconnect.
In this step, after the completion of the first loop line change-over switch closure of the first inverter side, feedback letter is sent to control system Number, after control system receives the feedback signal, signal is sent to control the second loop line change-over switch of the first inverter side to disconnect.
S140, the feedback signal that the second loop line change-over switch disconnection of the first inverter side is completed is received, it is inverse to described second The the first loop line change-over switch for becoming side sends the second close command, to control the first loop line change-over switch of second inverter side Closure.
In this step, after the completion of the second loop line change-over switch disconnection of the first inverter side, feedback letter is sent to control system Number, after control system receives the feedback signal, signal is sent to control the first loop line change-over switch of the second inverter side to close.
S150, the feedback signal that the first loop line change-over switch closure of the second inverter side is completed is received, it is inverse to described second The the second loop line change-over switch for becoming side sends the second open command, to control the second loop line change-over switch of second inverter side Disconnect.
In this step, after the completion of the first loop line change-over switch closure of the second inverter side, feedback letter is sent to control system Number, after control system receives the feedback signal, signal is sent to control the second loop line change-over switch of the second inverter side to disconnect.
The embodiment of the present invention, the order being opened or closed of the direct current change-over switch by controlling three end straight-flow systems, can Filled to the phenomenon of the other end, entered because direct current change-over switch disconnects and closes the electric current for inverter side one end occur with avoiding the occurrence of system And ensure that, when changing the method for operation of three end straight-flow systems, three end straight-flow systems can be run with security and stability, ensure person peace Entirely.
In one embodiment, the control method of the direct current change-over switch also includes：Receive second time of the second inverter side Line change-over switch disconnects the feedback signal completed, and is changed to the first loop line change-over switch of first inverter side and the second loop line Switch, the first loop line change-over switch of the second inverter side and the second loop line change-over switch send second and forbid instructing respectively, to prevent Only the first loop line change-over switch of first inverter side and the second loop line change-over switch, the first loop line conversion of the second inverter side Switch and the second loop line change-over switch malfunction.
The present embodiment second inverter side the second loop line change-over switch disconnect after the completion of, second inverter side Second loop line change-over switch sends and feeds back signal to control system, after control system receives the feedback signal, to the first inversion All direct current change-over switches of side and the second inverter side, which are sent, forbids control signal, to prevent these change-over switch malfunctions.Pass through Prevent all switch malfunctions from can effectively prevent the maloperation of switch and cause that electric current pours in down a chimney the occurrence of.
In one embodiment, three end straight-flow system also includes rectification side；First inverter side or the second inverter side It is connected by DC line with the rectification side, in the change of current for the first inverter side or the second inverter side being connected with the rectification side In standing, first inverter side is connected with the second inverter side by DC line.
As shown in figure 4, Fig. 4 is the equivalent circuit diagram of the direct current change-over switch of three end straight-flow systems in an embodiment.Wherein, Each DC terminal actually represents a DC converter station.It is inverse for first when the first inverter side is connected with rectification side Become side (x ends are expressed as in Fig. 4), except connecting the DC line being connected with rectification side, also to connect and be connected with the second inverter side DC line, the first inverter side and the second inverter side are actually parallel relationship, therefore the first inverter side and the second inverter side DC line be intersected in the current conversion station of the first inverter side.The present embodiment reconnects an inversion from the straight-flow system of both ends Side, formed with a rectification side, three end straight-flow systems of two inverter sides, can guarantee that more multicomponent is linked into DC power transmission system In system.
In one embodiment, first loop line is Ground return, and second loop line is metallic return；Described first time Line change-over switch is Ground return change-over switch, for controlling the DC current of three end straight-flow system from metallic return path Be converted to Ground return path；The second loop line change-over switch is metallic return change-over switch, for controlling three end straight The DC current of streaming system is converted to metallic return path from Ground return path.
In the present embodiment, the first loop line is Ground return, and the second loop line is metallic return, therefore, the first loop line path The state that state turns the second loop line path turns to metallic return path for DC current from Ground return path.
In one embodiment, first loop line is metallic return, and second loop line is Ground return；Described first time Line change-over switch is metallic return change-over switch, for controlling the DC current of three end straight-flow system from Ground return path Be converted to metallic return path；The second loop line change-over switch is Ground return change-over switch, for controlling three end straight The DC current of streaming system is converted to Ground return path from metallic return path.
In the present embodiment, the first loop line is metallic return, and the second loop line is Ground return, therefore, the first loop line path The state that state turns the second loop line path turns to Ground return path for DC current from metallic return path.
Alternatively, the transfer process of electric current is fairly simple in traditional both ends direct current change-over switch operating method.And for Three end direct current change-over switch operations, it is necessary to performed in strict accordance with certain conversion order.The embodiment of the present invention is that direct current is changed The improvement that cooperation between switch and control system is carried out.Therefore, for the operating method of change-over switch, except according to the present invention The signified order of embodiment will also give switching manipulation a definite limitation and cooperation outside being operated.
In order to more fully understand the above method, the control method of a direct current change-over switch of the present invention detailed below Application example.
Fig. 2 is three end straight-flow system schematic diagrames.It is different from both ends straight-flow system, except rectification side 210, three end straight-flow systems Two DC terminals, respectively the first inverter side 220 and the second inverter side 230 are also accessed in inverter side.First inverter side 220 and Two inverter sides 230 have been respectively coupled direct current change-over switch MRTB and ERTB, in polar curve in the current conversion station of the first inverter side 220 It is connected with drawing a circuit on neutral bus respectively with the second inverter side 230.
The equivalent circuit diagram that Fig. 3 switchs for both ends straight-flow system MRTB/ERTB, wherein RMRepresent metallic(return) circuit resistance (pole Line), LM- metallic return inductance (polar curve), RELRepresent earthing pole line resistance, REERepresent ground connection electrode resistance, LELRepresent ground connection polar curve Inductance, LGRepresent Ground return inductance, RGRepresent Ground return resistance, CSRepresent surge electric capacity, IdcFor DC current.For two Straight-flow system is held, the operation of direct current change-over switch is divided into following two：
First, Ground return pattern turns metallic return pattern (DC circuit Ground return path turns metallic return path)：It is first First, closure ERTB forms metallic(return) circuit, because MRTB is in "on" position, now metallic(return) circuit and ground return circuit parallel running； Then, MRTB is disconnected, DC current all flows through metallic(return) circuit, completes DC current and turns from ground return circuit to metallic(return) circuit Change.
Second, metallic return pattern turns Ground return pattern：First, close MRTB and form ground return circuit, because ERTB is in "on" position, now metallic(return) circuit and ground return circuit parallel running；Then, ERTB is disconnected, DC current all flows through the earth and returned Road, complete conversion of the DC current from metallic(return) circuit to ground return circuit.
It can also analyze and learn from Fig. 3, because the change-over switch of both ends straight-flow system only has 2, the operation each switched State can have 2 kinds of disconnection and closure, therefore the method for operation of opposite ends straight-flow system shares 22=4 kinds.
Fig. 4 show the equivalent circuit diagram of three end straight-flow system MRTB/ERTB switches, and comparison diagram 2 and Fig. 3 can be seen that Due to increasing a DC terminal newly, when three end straight-flow systems will be from Ground return/metallic return patten transformation to metallic return/the earth During pattern, the change-over switch operating method of response will become sufficiently complex, and due to three end direct currents, both ends all have 2 directly wherein Change-over switch is flowed, therefore the method for operation of three end direct currents will up to 42=16 kinds.
Fig. 5 show the three end straight-flow system d sides in the state of metallic return is turned from Ground return and is in metallic return mould The equivalent circuit diagram that formula, x sides are under the earth and metallic return modes parallel operating condition, under such a operating mode, d ends the earth returns Line current will pass through interconnection and flow into x stations so that the earth current in x stations greatly increases, bad by being produced to the operation of system Influence.
When Fig. 6 (a)~(e) is that Ground return turns metallic return operation, the front and rear system equivalent circuit of change-over switch action Figure.
Fig. 6 (a) be from Ground return turn metallic return in the state of three end straight-flow system x ends close ERTBxPreceding is equivalent Circuit diagram, now, MRTBxAnd MRTBdClosure.
The signal of three end straight-flow systems of conversion is received, control enable signal, control described three are sent to three end straight-flow systems Straight-flow system is held to enter the state from the state shift metallic return path of Ground return path.To ERTBxSend the first closure Instruction, control ERTBxClosure, obtains the circuit diagram such as Fig. 6 (b), and Fig. 6 (b) is in the state of Ground return turns metallic return Equivalent circuit diagram after three the first inverter sides of end straight-flow system closure Ground return change-over switch.Meanwhile control system sends the One forbids instructing, to prevent ERTBd、 MRTBxAnd MRTBdMalfunction.
ERTBxClosed procedure is carried out according to the first close command, control system receives ERTBxAfter the feedback signal of closure, To MRTBxThe first open command is sent, control disconnects MRTBx, the circuit diagram such as Fig. 6 (c) is obtained, Fig. 6 (c) is from Ground return Three the first inverter sides of end straight-flow system disconnect the equivalent circuit diagram after metallic return change-over switch in the state of turning metallic return.
MRTBxOperation is turned off according to the first open command, control system receives MRTBxAfter the feedback signal of disconnection, To ERTBdSend the second close command, control closure ERTBd, the circuit diagram such as Fig. 6 (d) is obtained, Fig. 6 (d) is from Ground return Three the second inverter sides of end straight-flow system close the equivalent circuit diagram after Ground return change-over switch in the state of turning metallic return；
ERTBdClosed procedure is carried out according to the second close command, control system receives ERTBdAfter the feedback signal of closure, To MRTBdThe first open command is sent, control disconnects MRTBd, the circuit diagram such as Fig. 6 (d) is obtained, Fig. 6 (e) is from Ground return Three the second inverter sides of end straight-flow system disconnect the equivalent circuit diagram after metallic return change-over switch in the state of turning metallic return；Together When to ERTBx、ERTBd、MRTBxAnd MRTBdSend second to forbid instructing, to prevent ERTBx、ERTBd、MRTBxAnd MRTBdMalfunction.
MRTBdOperation is turned off according to the second open command, Ground return is completed and turns the straight of the metallic return method of operation Flow the operating process of change-over switch.
In summary, turn the metallic return method of operation for Ground return, close the ERTB of x sides firstx, it is then turned off x The MRTB of sidex, it is closed again the ERTB of d sidesd, finally disconnect the MRTB of d sidesd.This operating method effectively prevent d sides electric current and fall The situation for filling x sides occurs, it is ensured that system safety operation.
The change-over switch action that metallic return turns Ground return turns that metallic return is corresponding with Ground return, in metallic return Under state, ERTBx、ERTBdClosure.The specific control process of direct current change-over switch is：Receive the letter of three end straight-flow systems of conversion Number, control enable signal is sent to three end straight-flow systems, control three end straight-flow system enters the shape from metallic return path State turns to the state of Ground return path, to MRTBdThe first close command is sent, controls MRTBdClosure, meanwhile, control system hair First is sent to forbid instructing, to prevent ERTBx、 ERTBdAnd MRTBxMalfunction.
MRTBdClosed procedure is carried out according to the first close command, control system receives MRTBdAfter the feedback signal of closure, To ERTBdThe first open command is sent, control disconnects ERTBd。
ERTBdOperation is turned off according to the first open command, control system receives ERTBdAfter the feedback signal of disconnection, To MRTBxSend the second close command, control closure MRTBx。
MRTBxClosed procedure is carried out according to the second close command, control system receives closure MRTBxAfter feedback signal, to ERTBxThe second open command is sent, control disconnects ERTBx, while to ERTBx、ERTBd、 MRTBxAnd MRTBdSecond is sent to forbid Instruction, to prevent ERTBx、ERTBd、MRTBxAnd MRTBdMalfunction.
ERTBxOperation is turned off according to the second open command, metallic return is completed and turns the straight of the Ground return method of operation Flow the operating process of change-over switch.
In summary, turn the Ground return method of operation for metallic return, close the MRTB of d sides firstd, it is then turned off d The ERTB of sided, it is closed again the MRTB of x sidesx, finally disconnect the ERTB of x sidesx.This operating method effectively prevent what electric current poured in down a chimney Situation occurs, it is ensured that system safety operation.
It should be noted that for foregoing each method embodiment, in order to which simplicity describes, it is all expressed as a series of Combination of actions, but those skilled in the art should know, the present invention is not limited by described sequence of movement, because according to According to the present invention, some steps can use other orders or carry out simultaneously.
Based on the control method identical thought with the direct current change-over switch in above-described embodiment, the present invention also provides direct current The control device of change-over switch, the device can be used for the control method for performing above-mentioned direct current change-over switch.For convenience of description, directly In the structural representation for flowing the control device embodiment of change-over switch, the part related to the embodiment of the present invention is illustrate only, It will be understood by those skilled in the art that the restriction of schematic structure not structure twin installation, can include more more or less than illustrating Part, either combine some parts or different parts arrangement.
As described in Figure 7, the control device of direct current change-over switch includes control signal receiving module 510, first switch controls Module 520, second switch control module 530, the 3rd switch control module 540 and the 4th switch control module 550, describe in detail It is as follows：
Control signal receiving module 510, for receiving the signal of three end straight-flow systems of conversion, sent to three end straight-flow systems Enable signal is controlled, control three end straight-flow system enters the shape from state shift the second loop line path of the first loop line path State；Wherein, three end straight-flow system includes the first inverter side and the second inverter side, and the first inverter side, the second inverter side are wrapped Containing the first loop line and the second loop line.
First switch control module 520, for entering in three end straight-flow systems from the state shift of the first loop line path the In the state of two loop line paths, the first close command is sent to the first loop line change-over switch of the first inverter side, with described in control The first loop line change-over switch closure of first inverter side；The second loop line change-over switch to the first inverter side, the second inversion simultaneously The first loop line change-over switch, the second loop line change-over switch of side, which send first, to be forbidden instructing, to prevent first inverter side Second loop line change-over switch, the first loop line change-over switch of the second inverter side and the second loop line change-over switch malfunction.
Second switch control module 530, the first loop line change-over switch closure for receiving the first inverter side are completed anti- Feedback signal, the first open command is sent to the second loop line change-over switch of first inverter side, to control first inversion Second loop line change-over switch of side disconnects.
3rd switch control module 540, the second loop line change-over switch for receiving the first inverter side disconnect the anti-of completion Feedback signal, the second close command is sent to the first loop line change-over switch of second inverter side, to control second inversion The first loop line change-over switch closure of side.
4th switch control module 550, the first loop line change-over switch closure for receiving the second inverter side are completed anti- Feedback signal, the second open command is sent to the second loop line change-over switch of second inverter side, to control second inversion Second loop line change-over switch of side disconnects.
In one embodiment, the control device of the direct current change-over switch also includes：Malfunction control module, for receiving the Second loop line change-over switch of two inverter sides disconnects the feedback signal completed, and the first loop line conversion to first inverter side is opened Close and the second loop line change-over switch, the first loop line change-over switch of the second inverter side and the second loop line change-over switch send the respectively Two forbid instructing, to prevent the first loop line change-over switch of first inverter side and the second loop line change-over switch, the second inversion First loop line change-over switch of side and the second loop line change-over switch malfunction.
In an alternative embodiment, three end straight-flow system also includes rectification side；First inverter side is second inverse Become side by DC line with the rectification side to be connected, in the first inverter side or the second inverter side being connected with the rectification side In current conversion station, first inverter side is connected with the second inverter side by DC line.
In an alternative embodiment, first loop line is Ground return, and second loop line is metallic return；Described One loop line change-over switch is Ground return change-over switch, for controlling the DC current of three end straight-flow system from metallic return Path is converted to Ground return path；The second loop line change-over switch is metallic return change-over switch, for controlling described three The DC current of end straight-flow system is converted to metallic return path from Ground return path.
In an alternative embodiment, first loop line is metallic return, and second loop line is Ground return；Described One loop line change-over switch is metallic return change-over switch, for controlling the DC current of three end straight-flow system from Ground return Path is converted to metallic return path；The second loop line change-over switch is Ground return change-over switch, for controlling described three The DC current of end straight-flow system is converted to Ground return path from metallic return path.
It should be noted that the control of the control device of the direct current change-over switch of the present invention and the direct current change-over switch of the present invention Method processed corresponds, the technical characteristic and its advantage illustrated in the embodiment of the control method of above-mentioned direct current change-over switch Suitable for the embodiment of the control device of direct current change-over switch, particular content can be found in chatting in the inventive method embodiment State, here is omitted, hereby give notice that.
In addition, in the embodiment of the control device of the direct current change-over switch of above-mentioned example, the logic of each program module is drawn Divide and be merely illustrative of, can be as needed in practical application, such as configuration requirement or the reality of software for corresponding hardware Existing convenient consideration, above-mentioned function distribution is completed by different program modules, will the direct current change-over switch control dress The internal structure put is divided into different program modules, to complete all or part of function described above.
In the above-described embodiments, the description to each embodiment all emphasizes particularly on different fields, and does not have the portion being described in detail in some embodiment Point, it may refer to the associated description of other embodiments.It is appreciated that wherein used term " first ", " second " etc. are at this It is used to distinguish object in text, but these objects should not be limited by these terms.
It will appreciated by the skilled person that realizing all or part of flow in above-described embodiment method, being can To instruct the hardware of correlation to complete by computer program, described program can be stored in a computer-readable storage and be situated between In matter, as independent production marketing or use.The more specifically example (non-exhaustive list) of computer-readable medium includes Below：Electrical connection section (electronic installation) with one or more wiring, portable computer diskette box (magnetic device), arbitrary access Memory (RAM), read-only storage (ROM), erasable edit read-only storage (EPROM or flash memory), optical fiber dress Put, and portable optic disk read-only storage (CDROM).It can be printed in addition, computer-readable medium can even is that thereon The paper of described program or other suitable media, because can be for example by carrying out optical scanner to paper or other media, then Enter edlin, interpretation or handled if necessary with other suitable methods electronically to obtain described program, then by it It is stored in computer storage.
It should be appreciated that each several part of the present invention can be realized with hardware, software, firmware or combinations thereof.Above-mentioned In embodiment, software that multiple steps or method can be performed in memory and by suitable instruction execution system with storage Or firmware is realized.If, and in another embodiment, can be with well known in the art for example, realized with hardware Any one of row technology or their combination are realized：With the logic gates for realizing logic function to data-signal Discrete logic, have suitable combinational logic gate circuit application specific integrated circuit, programmable gate array (PGA), scene Programmable gate array (FPGA) etc..
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show The description of example " or " some examples " etc. means specific features, structure, material or the spy for combining the embodiment or example description Point is contained at least one embodiment or example of the present invention.In this manual, to the schematic representation of above-mentioned term not Necessarily refer to identical embodiment or example.Moreover, specific features, structure, material or the feature of description can be any One or more embodiments or example in combine in an appropriate manner.
Each technical characteristic of embodiment described above can be combined arbitrarily, to make description succinct, not to above-mentioned reality Apply all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited In contradiction, the scope that this specification is recorded all is considered to be.
Embodiment described above only expresses the several embodiments of the present invention, it is impossible to is interpreted as to the scope of the claims of the present invention Limitation.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, Various modifications and improvements can be made, these belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention It should be determined by the appended claims.

Claims (10)

  1. A kind of 1. control method of direct current change-over switch, it is characterised in that including：
    The signal of three end straight-flow systems of conversion is received, control enable signal is sent to three end straight-flow systems, controls three end straight Streaming system enters the state from state shift the second loop line path of the first loop line path；Wherein, the three ends straight-flow system bag The first inverter side and the second inverter side are included, the first inverter side, the second inverter side include the first loop line and the second loop line；
    In the state of state shift the second loop line path that three end straight-flow systems enter from the first loop line path, to the first inversion First loop line change-over switch of side sends the first close command, to control the first loop line change-over switch of first inverter side to close Close；Turn simultaneously to the second loop line change-over switch of the first inverter side, the first loop line change-over switch of the second inverter side, the second loop line Change switch and send and first forbid instructing, with prevent the second loop line change-over switch of first inverter side, the second inverter side the One loop line change-over switch and the second loop line change-over switch malfunction；
    The feedback signal that the first loop line change-over switch closure of the first inverter side is completed is received, to the second of first inverter side Loop line change-over switch sends the first open command, to control the second loop line change-over switch of first inverter side to disconnect；
    The the second loop line change-over switch for receiving the first inverter side disconnects the feedback signal completed, to the first of second inverter side Loop line change-over switch sends the second close command, to control the first loop line change-over switch of second inverter side to close；
    The feedback signal that the first loop line change-over switch closure of the second inverter side is completed is received, to the second of second inverter side Loop line change-over switch sends the second open command, to control the second loop line change-over switch of second inverter side to disconnect.
  2. 2. the control method of direct current change-over switch according to claim 1, it is characterised in that the second inverter side of the reception The feedback signal completed of the first loop line change-over switch closure, send the to the second loop line change-over switch of second inverter side Two open commands, after controlling the second loop line change-over switch of second inverter side to disconnect, in addition to：
    The the second loop line change-over switch for receiving the second inverter side disconnects the feedback signal completed, to the first of first inverter side Loop line change-over switch and the second loop line change-over switch, the first loop line change-over switch and the second loop line change-over switch of the second inverter side Send second respectively to forbid instructing, to prevent the first loop line change-over switch of first inverter side and the second loop line from changing and opening Pass, the first loop line change-over switch of the second inverter side and the second loop line change-over switch malfunction.
  3. 3. the control method of direct current change-over switch according to claim 1 or 2, it is characterised in that the three ends direct current system System also includes rectification side；
    First inverter side or the second inverter side are connected by DC line with the rectification side, are connected with the rectification side The first inverter side or the second inverter side current conversion station in, first inverter side and the second inverter side pass through DC line phase Even.
  4. 4. the control method of direct current change-over switch according to claim 1 or 2, it is characterised in that
    First loop line is Ground return, and second loop line is metallic return；
    The first loop line change-over switch is Ground return change-over switch, for controlling the DC current of three end straight-flow system Ground return path is converted to from metallic return path；
    The second loop line change-over switch is metallic return change-over switch, for controlling the DC current of three end straight-flow system Metallic return path is converted to from Ground return path；
    Or,
    First loop line is metallic return, and second loop line is Ground return；
    The first loop line change-over switch is metallic return change-over switch, for controlling the DC current of three end straight-flow system Metallic return path is converted to from Ground return path；
    The second loop line change-over switch is Ground return change-over switch, for controlling the DC current of three end straight-flow system Ground return path is converted to from metallic return path.
  5. A kind of 5. control device of direct current change-over switch, it is characterised in that including：
    Control signal receiving module, for receiving the signal of three end straight-flow systems of conversion, sending control to three end straight-flow systems makes Energy signal, control three end straight-flow system enter the state from state shift the second loop line path of the first loop line path；Its In, three end straight-flow system includes the first inverter side and the second inverter side, and the first inverter side, the second inverter side include first Loop line and the second loop line；
    First switch control module, lead to for entering in three end straight-flow systems from the loop line of state shift second of the first loop line path In the state of road, the first close command is sent to the first loop line change-over switch of the first inverter side, to control first inversion The first loop line change-over switch closure of side；The second loop line change-over switch to the first inverter side, the first of the second inverter side simultaneously Loop line change-over switch, the second loop line change-over switch, which send first, to be forbidden instructing, to prevent the second loop line of first inverter side Change-over switch, the first loop line change-over switch of the second inverter side and the second loop line change-over switch malfunction；
    Second switch control module, the feedback signal that the first loop line change-over switch closure for receiving the first inverter side is completed, The first open command is sent to the second loop line change-over switch of first inverter side, to control the second of first inverter side Loop line change-over switch disconnects；
    3rd switch control module, the second loop line change-over switch for receiving the first inverter side disconnect the feedback signal completed, The second close command is sent to the first loop line change-over switch of second inverter side, to control the first of second inverter side Loop line change-over switch closes；
    And the 4th switch control module, the feedback that the first loop line change-over switch closure for receiving the second inverter side is completed Signal, the second open command is sent to the second loop line change-over switch of second inverter side, to control second inverter side The second loop line change-over switch disconnect.
  6. 6. the control device of direct current change-over switch according to claim 5, it is characterised in that also include：
    Malfunction control module, the second loop line change-over switch for receiving the second inverter side disconnects the feedback signal completed, to institute State the first loop line change-over switch and the second loop line change-over switch, the first loop line change-over switch of the second inverter side of the first inverter side Second is sent respectively with the second loop line change-over switch to forbid instructing, to prevent the first loop line change-over switch of first inverter side With the second loop line change-over switch, the first loop line change-over switch of the second inverter side and the second loop line change-over switch malfunction.
  7. 7. the control device of the direct current change-over switch according to claim 5 or 6, it is characterised in that
    Three end straight-flow system also includes rectification side；
    First inverter side or the second inverter side are connected by DC line with the rectification side, are connected with the rectification side The first inverter side or the second inverter side current conversion station in, first inverter side and the second inverter side pass through DC line phase Even.
  8. 8. the control device of the direct current change-over switch according to claim 5 or 6, it is characterised in that
    First loop line is Ground return, and second loop line is metallic return；
    The first loop line change-over switch is Ground return change-over switch, for controlling the DC current of three end straight-flow system Ground return path is converted to from metallic return path；
    The second loop line change-over switch is metallic return change-over switch, for controlling the DC current of three end straight-flow system Metallic return path is converted to from Ground return path；
    Or,
    First loop line is metallic return, and second loop line is Ground return；
    The first loop line change-over switch is metallic return change-over switch, for controlling the DC current of three end straight-flow system Metallic return path is converted to from Ground return path；
    The second loop line change-over switch is Ground return change-over switch, for controlling the DC current of three end straight-flow system Ground return path is converted to from metallic return path.
  9. 9. a kind of computer-readable recording medium, is stored thereon with computer program, it is characterised in that the program is held by processor The step of Claims 1-4 any methods described is realized during row.
  10. 10. a kind of computer equipment, including memory, processor and storage are on a memory and the meter that can run on a processor Calculation machine program, it is characterised in that the step of any methods described of Claims 1-4 is realized during the computing device described program Suddenly.
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CN112260303A (en) * 2020-06-04 2021-01-22 许继集团有限公司 LCC parallel three-terminal metal ground transfer switch sequence coordination control method and system
CN113555858A (en) * 2021-07-28 2021-10-26 中国南方电网有限责任公司超高压输电公司昆明局 Control method, device and protection system for direct current power transmission system under metal return wire

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CN106532659A (en) * 2016-12-15 2017-03-22 国家电网公司 Control protective method for ultra-high-voltage direct-current engineering direct-current change-over switch with parallel structure
CN106936153A (en) * 2017-04-28 2017-07-07 南方电网科学研究院有限责任公司 A kind of new extra-high voltage DC transmission system and method for operation changing method

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US20160036341A1 (en) * 2014-07-31 2016-02-04 Korea University Research And Business Foundation Power grid frequency flexible operation system and method using the same
CN106532659A (en) * 2016-12-15 2017-03-22 国家电网公司 Control protective method for ultra-high-voltage direct-current engineering direct-current change-over switch with parallel structure
CN106936153A (en) * 2017-04-28 2017-07-07 南方电网科学研究院有限责任公司 A kind of new extra-high voltage DC transmission system and method for operation changing method

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CN111244998A (en) * 2020-01-14 2020-06-05 南方电网科学研究院有限责任公司 Control method and device for converting single-pole ground return wire into metal return wire and storage medium
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