CN112688547A - Fault-tolerant control method and device for asymmetric operation fault of MMC-HCDC bridge arm - Google Patents
Fault-tolerant control method and device for asymmetric operation fault of MMC-HCDC bridge arm Download PDFInfo
- Publication number
- CN112688547A CN112688547A CN202011527736.6A CN202011527736A CN112688547A CN 112688547 A CN112688547 A CN 112688547A CN 202011527736 A CN202011527736 A CN 202011527736A CN 112688547 A CN112688547 A CN 112688547A
- Authority
- CN
- China
- Prior art keywords
- converter valve
- fault
- bridge arm
- module
- valve sub
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- 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]
Landscapes
- Inverter Devices (AREA)
Abstract
The invention discloses an MMC-HCDC bridge arm asymmetric operation fault-tolerant control method and a device, wherein the method comprises the following steps: calculating the initial input quantity of each bridge arm converter valve submodule according to the modulation wave of the direct-current pole control module; acquiring running state information uploaded by a converter valve submodule; acquiring the fault number of the converter valve sub-module according to the running state information uploaded by the converter valve sub-module; and correcting the initial input quantity of each bridge arm converter valve submodule according to the fault quantity of the converter valve submodules and the current direction of the bridge arms so as to eliminate the asymmetry of bridge arm current and the fluctuation of direct current caused by the faults of a plurality of converter valve submodules. The method comprises the steps of detecting state information of converter valve submodules in each bridge arm in real time, obtaining the number of converter valve submodules in a fault state, and correcting the number of the converter valve submodules in combination with the current direction of the bridge arm so as to eliminate the asymmetry of bridge arm current and the fluctuation of direct current caused by the faults of the converter valve submodules.
Description
Technical Field
The invention relates to the field of flexible power transmission control of a power system, in particular to an MMC-HCDC bridge arm asymmetric operation fault tolerance control method and device.
Background
With the development of fully-controlled power electronic devices and the application of power electronic technology in power systems, Voltage-source Converter High Voltage Direct Current (VSC-HVDC) technology based on Voltage source converters is increasingly gaining attention. The Modular Multilevel Converter (MMC) is one of voltage source converters in application of a flexible direct current transmission system, and is widely applied to flexible direct current transmission and a new energy access system with remarkable advantages.
Each bridge arm of the MMC-HVDC is formed by connecting a certain number of sub-modules and bridge arm reactors in series, the number of the sub-modules which are put into and cut off by each bridge arm is controlled, so that the output voltage of an alternating current side approaches to alternating current sinusoidal voltage, the output voltage of a direct current side approaches to direct current voltage, and the stable operation of a system is realized. The MMC-HVDC control system can be divided according to function into: the system comprises a telecontrol communication module, an operator control module, a coordination control module (with multiple ends), an alternating current station control module, a direct current pole control module, a valve control module and all sub-modules which are communicated through standard interfaces. The valve control system is a control and monitoring system of the flexible direct current converter valve part and mainly receives modulation waves issued by pole control to generate pulse control signals of the sub-modules. The valve control system has the functions of submodule voltage control, converter valve level protection, converter valve state monitoring and the like.
The MMC comprises a large number of cascaded submodules, and in order to ensure that the system has enough fault tolerance, a certain number of redundant submodules are generally selected to be connected in series for each bridge arm in engineering, so that enough safety margin is reserved for the system. When the MMC-HVDC normally operates, the number of 6 bridge arm sub-modules is equal, which is called a bridge arm symmetric state, and the number of 6 bridge arm sub-modules is not completely equal, which is called a bridge arm asymmetric state. The asymmetric state of the legs is generally due to the fact that some leg(s) have partial sub-modules that are bypassed due to a fault, resulting in a smaller number of sub-modules than other legs. The asymmetry of the bridge arm can cause the asymmetry of the MMC-HVDC bridge arm current and the asymmetry of the circulating current, thereby causing the fundamental frequency fluctuation of the direct current.
Disclosure of Invention
The invention aims to provide an MMC-HCDC bridge arm asymmetric operation fault-tolerant control method and device.
In order to solve the above technical problem, a first aspect of an embodiment of the present invention provides an MMC-HCDC bridge arm asymmetric operation fault tolerance control method, where the MMC-HCDC bridge arm control system includes: the direct current pole control module and the valve control module comprise the following steps:
calculating the initial input quantity N of each bridge arm converter valve submodule according to the modulation wave of the direct current pole control moduleputin；
Acquiring running state information uploaded by the converter valve submodule;
acquiring the fault number of the converter valve sub-module according to the operation state information uploaded by the converter valve sub-moduleNfault；
And correcting the initial input quantity of the converter valve sub-modules of each bridge arm according to the fault quantity of the converter valve sub-modules and the current directions of the bridge arms so as to eliminate the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the faults of a plurality of converter valve sub-modules.
Further, according to the fault number N of the converter valve sub-modulesfaultAnd the initial input quantity N of the current flow directions of the bridge arms to the converter valve sub-modules of each bridge armputinPerforming a correction comprising:
when the current direction of the bridge arm is the charging direction, correcting the input quantity of the converter valve sub-modules to the initial input quantity NputinAnd the number of faults NfaultSumming;
when the current direction of the bridge arm is the discharging direction, keeping the input quantity of the converter valve sub-modules to be the initial input quantity Nputin。
Further, the input quantity of the converter valve sub-modules is corrected to the initial input quantity NputinAnd the number of faults NfaultAnd (c) a sum comprising:
acquiring and sequencing capacitor voltage values;
inputting corresponding N according to the sequence of the capacitor voltage values from small to largeputin+NfaultEach converter valve sub-module.
Further, the input number N of the converter valve sub-modules isputinMaintaining at the initial plunge amount, comprising:
acquiring and sequencing capacitor voltage values;
inputting corresponding N according to the sequence of the capacitor voltage values from large to smallputinEach converter valve sub-module.
Further, the fault number N of the converter valve sub-module is obtained according to the running state information uploaded by the converter valve sub-modulefaultThe method comprises the following steps:
when the bridge arm converter valve sub-module fails, controlling the converter valve sub-module in a failure state to close a bypass through a bypass switch;
uploading the capacitor voltage value of the converter valve submodule in a fault state to the valve control module, and uploading the state information of the converter valve submodule to the valve control module;
obtaining the fault number N of the converter valve sub-modulefault。
Correspondingly, a second aspect of the embodiments of the present invention provides an MMC-HCDC bridge arm asymmetric operation fault-tolerant control apparatus, where the MMC-HCDC bridge arm control system includes: direct current utmost point accuse module and valve control module include:
a first calculation module for calculating the initial input quantity N of each bridge arm converter valve submodule according to the modulation wave of the direct current pole control moduleputin；
The first acquisition module is used for acquiring the running state information uploaded by the converter valve submodule;
a second obtaining module, configured to obtain the number N of faults of the converter valve submodule according to the running state information uploaded by the converter valve submodulefault；
And the control module corrects the initial input quantity of the converter valve sub-modules of each bridge arm according to the fault quantity of the converter valve sub-modules and the current directions of the bridge arms so as to eliminate the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the faults of the converter valve sub-modules.
Further, the control module includes:
a first control unit for correcting the input number of the converter valve sub-modules to the initial input number N when the current direction of the bridge arm is a charging directionputinAnd the number of faults NfaultSumming;
a second control unit for maintaining the input number of the converter valve submodules to the initial input number N when the current direction of the bridge arm is the discharging directionputin。
Further, the first control unit includes:
the first acquiring subunit is used for acquiring and sequencing the capacitor voltage values;
a first control subunit for inputting corresponding N according to the sequence of the capacitor voltage values from small to largeputin+NfaultEach converter valve sub-module.
Further, the first control unit includes:
the second acquisition subunit is used for acquiring and sequencing the capacitor voltage values;
a second control subunit for inputting corresponding N according to the sequence of the capacitor voltage values from large to smallputinEach converter valve sub-module.
Further, the second obtaining module includes:
the third control unit is used for controlling the converter valve sub-module in a fault state to close a bypass through a bypass switch when the bridge arm converter valve sub-module fails;
the data transmission unit is used for uploading the capacitance voltage value of the converter valve sub-module in a fault state to the valve control module and uploading the state information of the converter valve sub-module to the valve control module;
a third obtaining unit for obtaining the fault number N of the converter valve submodulefault。
The technical scheme of the embodiment of the invention has the following beneficial technical effects:
the state information of the converter valve sub-modules in each bridge arm is detected in real time, the fault number of the converter valve sub-modules in the fault state is obtained, the number of the converter valve sub-modules put into each bridge arm is corrected by combining the current direction of the bridge arm, so that the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the asymmetry of the bridge arms due to the faults of the converter valve sub-modules are eliminated, and the stability and the safety of system operation are improved.
Drawings
FIG. 1 is a flowchart of an MMC-HCDC bridge arm asymmetric operation fault-tolerant control method provided by an embodiment of the present invention;
FIG. 2 is a logic diagram of an MMC-HCDC bridge arm asymmetrical operation fault-tolerant control method provided by the embodiment of the invention;
FIG. 3 is a waveform diagram related to a fault-tolerant control system for asymmetric operation of a bridge arm according to an embodiment of the present invention;
FIG. 4 is a waveform diagram related to fault-tolerant control-modulation wave correction provided by an embodiment of the present invention;
FIG. 5 is a schematic diagram of a module of an MMC-HCDC bridge arm asymmetric operation fault-tolerant control device provided by an embodiment of the present invention;
FIG. 6 is a schematic diagram of a second obtaining module according to an embodiment of the present invention;
FIG. 7 is a schematic diagram of a control module provided by an embodiment of the present invention;
fig. 8 is a schematic diagram of a first control unit according to an embodiment of the present invention.
Reference numerals:
1. the system comprises a first calculation module, 2, a first acquisition module, 3, a second acquisition module, 31, a third control unit, 32, a data transmission unit, 33, a third acquisition unit, 4, a control module, 41, a first control unit, 411, a first acquisition subunit, 412, a first control subunit, 413, a second acquisition subunit, 414, a second control subunit, 42 and a second control unit.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It should be understood that the description is intended to be exemplary only, and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
Fig. 1 is a flowchart of an MMC-HCDC bridge arm asymmetric operation fault-tolerant control method provided by an embodiment of the present invention.
FIG. 2 is a logic diagram of an MMC-HCDC bridge arm asymmetrical operation fault-tolerant control method provided by the embodiment of the invention.
Referring to fig. 1 and fig. 2, a first aspect of an embodiment of the present invention provides an MMC-HCDC bridge arm asymmetric operation fault tolerance control method, where the MMC-HCDC bridge arm control system includes: the direct current pole control module and the valve control module comprise the following steps:
s100, calculating the initial input quantity N of each bridge arm converter valve submodule according to the modulation wave of the direct current pole control moduleputin。
And S200, acquiring running state information uploaded by the converter valve submodule.
S300, acquiring the fault number N of the converter valve submodule according to the running state information uploaded by the converter valve submodulefault。
S400, correcting the initial input quantity of each bridge arm converter valve submodule according to the fault quantity of the converter valve submodules and the current direction of the bridge arms so as to eliminate the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the faults of the plurality of converter valve submodules.
According to the technical scheme, the state information of the converter valve sub-modules in each bridge arm is detected in real time, the fault number of the converter valve sub-modules in the fault state is obtained, the number of the converter valve sub-modules put into each bridge arm is corrected by combining the current direction of the bridge arm, so that the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the asymmetry of the bridge arms due to the faults of the converter valve sub-modules are eliminated, and the stability and the safety of system operation are improved.
In particular, according to the fault number N of the converter valve submodulefaultAnd the initial input quantity N of the current flow directions of the bridge arms to each bridge arm converter valve submoduleputinPerforming a correction comprising:
s410, when the current direction of the bridge arm is the charging direction, correcting the input quantity of the converter valve sub-modules to be the initial input quantity NputinAnd the number of faults NfaultAnd (4) summing.
When the direction of the bridge arm current is positive, according to an MMC voltage-sharing strategy, the lower voltage needs to be input, and the higher voltage needs to be cut off. The voltage value after the fault is set to be 0, and the voltage values are arranged during the sequencingAt the minimum position, the converter valve sub-modules in the fault state are put in when the current direction of the bridge arm is positive, the input quantity comprises fault numbers, and the actually executed input quantity is smaller than the initial input quantity Nputin. In order to eliminate the influence caused by the reduction of the input number, the input number of the converter valve sub-modules is corrected, namely the actual input number is equal to the initial input number NputinAnd the number of faults NfaultAnd (4) summing.
S420, when the current direction of the bridge arm is the discharging direction, keeping the input quantity of the converter valve submodules to be the initial input quantity Nputin。
When the current direction of a bridge arm is positive, according to an MMC voltage-sharing strategy, high voltage needs to be input, low voltage is cut off, the voltage value is set to be 0 after the fault, the voltage value is arranged at the minimum position during sequencing, when the current is negative, the voltage-high converter valve submodule is input, and the voltage-low converter valve submodule is cut off. The voltage in the fault state is the lowest, the input is not carried out, and the fault state is in the cut-off state, so the input number is kept to be the initial input number Nputin。
Specifically, the input quantity of the converter valve sub-modules is corrected to be the initial input quantity NputinAnd the number of faults NfaultAnd (c) a sum comprising:
and S411, acquiring and sequencing the capacitor voltage values.
S412, inputting corresponding N according to the sequence of the capacitor voltage values from small to largeputin+NfaultAnd each converter valve submodule.
Specifically, the input number N of converter valve submodulesputinMaintaining at an initial input quantity comprising:
and S421, acquiring and sequencing the capacitor voltage values.
S422, inputting corresponding N according to the sequence of the capacitor voltage values from large to smallputinAnd each converter valve submodule.
Further, the fault number N of the converter valve submodule is obtained according to the running state information uploaded by the converter valve submodulefaultThe method comprises the following steps:
and S310, when the bridge arm converter valve sub-module fails, controlling the converter valve sub-module in the failure state to close the bypass through the bypass switch.
And S320, uploading the capacitor voltage value of the converter valve submodule in the fault state to a valve control module, and uploading the state information of the converter valve submodule to the valve control module.
S330, acquiring the fault number N of the converter valve sub-modulesfault。
Fig. 3 is a waveform diagram related to a fault-tolerant control system for asymmetric operation of a bridge arm according to an embodiment of the present invention.
Fig. 4 is a waveform diagram related to fault-tolerant control-modulation wave correction provided by an embodiment of the invention.
Referring to fig. 3 and fig. 4, firstly, the MMC-HVDC system operates normally, and at a certain time (1.2s), the three-phase upper bridge arm simulates that the sub-module fails at the same time, and the number of the failures is redundant (16). And the fault sub-module locks the bypass, the voltage of the capacitor of the uploading valve control system is 0, and the redundant module is converted into a normal running state from a hot standby state. And the valve control module receives the modulated wave of the direct current pole control module in real time and converts the modulated wave into the input number, and records the number of the converter valve sub-modules with each bridge arm fault.
And when the six bridge arms have no converter valve sub-module fault and the bridge arms run symmetrically, the valve control system judges the current direction of the bridge arms in real time, the capacitor voltages of the sub-modules are completely sequenced, and the input and cut sub-modules are selected according to the sequencing result. And the six bridge arms are independently controlled, and when each bridge arm detects that the converter valve submodule has a fault, the fault-tolerant strategy starts to enable. When the six-bridge-arm converter valve sub-modules have faults and the bridge arms operate symmetrically, the valve control module judges the current directions of the bridge arms in real time, the capacitor voltages of the converter valve sub-modules are completely sorted, and the sorted converter valve sub-modules are arranged at the lowest position due to the fact that the capacitor voltages of the faulty converter valve sub-modules are uploaded to be 0. The valve control system corrects the modulated wave under polar control by combining the current direction of the bridge arm and the number of fault sub-modules; when the bridge arm current is in the charging direction, the number of the input modules is corrected to be NPutin+Nfault, according to the sorting result, selecting N with low voltagePutin+NfauThe lt is put into, and other converter valve sub-modules are cut off; the number of input modules is corrected by 1.201s in the simulation. Bridge arm current is setIn the electric direction, the number of the input converter valve sub-modules maintains the same number of the inputs issued by the direct current pole control module, and the number of the inputs is NPutinSelecting N with high voltage according to the sorting resultPutin is put into the mould and the rest of the mould is cut off.
Finally, the required alternating current side voltage and direct current side voltage are modulated by adopting a nearest level approximation algorithm according to the input number, as shown in fig. 3, the relevant waveforms of the fault tolerance strategy of the asymmetric operation of the bridge arm are shown, 1.2s of time of the fault of the submodule of the three-phase upper bridge arm converter valve is enabled, and 1.6s of the fault tolerance strategy is enabled. The bridge arm runs asymmetrically, the bridge arm current is distorted and asymmetric, and the direct current fluctuates at fundamental frequency; the 1.6s fault tolerance strategy enables, after enabling, the current asymmetry of the bridge arm disappears, the direct current fluctuation disappears, the control performance is good, and the basic value of the capacitor voltage of the converter valve submodule returns to normal and is consistent with that before the fault. Referring to fig. 4, the input modules are adjusted according to the current direction, and the input number is N when the current is in the charging direction (the current is positive)Putin + 16. When the current is in the discharging direction (the current is negative), the input number is NPutin。
Fig. 5 is a schematic diagram of a module of an MMC-HCDC bridge arm asymmetric operation fault-tolerant control device according to an embodiment of the present invention.
Correspondingly, referring to fig. 5, a second aspect of the embodiments of the present invention provides an MMC-HCDC bridge arm asymmetric operation fault-tolerant control apparatus, where the MMC-HCDC bridge arm control system includes: direct current utmost point accuse module and valve control module include: the device comprises a first calculation module 1, a first acquisition module 2, a second acquisition module 3 and a control module 4. The first calculation module 1 is used for calculating the initial input quantity N of each bridge arm converter valve submodule according to the modulation wave of the direct current pole control moduleputin(ii) a The first acquisition module 2 is used for acquiring running state information uploaded by the converter valve sub-module; the second obtaining module 3 is configured to obtain the number N of faults of the converter valve submodule according to the running state information uploaded by the converter valve submodulefault(ii) a The control module 4 inputs the initial input quantity of each bridge arm converter valve submodule according to the fault quantity of the converter valve submodules and the current direction of the bridge armsAnd correcting to eliminate the asymmetry of bridge arm current and the fluctuation of direct current caused by the faults of the plurality of converter valve sub-modules.
Fig. 6 is a schematic diagram of a second obtaining module according to an embodiment of the present invention.
Further, referring to fig. 6, the first control unit 41 includes: a second acquisition subunit 413 and a second control subunit 414. The second obtaining subunit 413 is configured to obtain capacitance voltage values and sort the capacitance voltage values; the second control subunit 414 is configured to apply the corresponding N values in the order of decreasing the capacitor voltage valueputinAnd each converter valve submodule.
Fig. 7 is a schematic diagram of a control module according to an embodiment of the present invention.
Specifically, referring to fig. 7, the control module 4 includes: a first control unit 41 and a second control unit 42. Wherein, the first control unit 41 is configured to modify the input number of the converter valve sub-modules to the initial input number N when the current direction of the bridge arm is the charging directionputinAnd the number of faults NfaultSumming; the second control unit 42 is used for keeping the input number of the converter valve submodules as the initial input number N when the current direction of the bridge arm is the discharging directionputin。
Fig. 8 is a schematic diagram of a first control unit according to an embodiment of the present invention.
Further, referring to fig. 8, the first control unit 41 includes: a first acquisition subunit 411 and a first control subunit 412. The first obtaining subunit 411 is configured to obtain capacitor voltage values and perform sorting; the first control subunit 412 is configured to input the corresponding N values in the order of the capacitor voltage values from small to largeputin+NfaultAnd each converter valve submodule.
According to the technical scheme, the state information of the converter valve sub-modules in each bridge arm is detected in real time, the fault number of the converter valve sub-modules in the fault state is obtained, the number of the converter valve sub-modules put into each bridge arm is corrected by combining the current direction of the bridge arm, so that the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the asymmetry of the bridge arms due to the faults of the converter valve sub-modules are eliminated, and the stability and the safety of system operation are improved.
The embodiment of the invention aims to protect an MMC-HCDC bridge arm asymmetric operation fault-tolerant control method and a device thereof, wherein the MMC-HCDC bridge arm control system comprises: the direct current pole control module and the valve control module, wherein the method comprises the following steps: calculating the initial input quantity N of each bridge arm converter valve submodule according to the modulation wave of the direct current pole control moduleputin(ii) a Acquiring running state information uploaded by a converter valve submodule; acquiring the fault number N of the converter valve submodule according to the running state information uploaded by the converter valve submodulefault(ii) a And correcting the initial input quantity of each bridge arm converter valve submodule according to the fault quantity of the converter valve submodules and the current direction of the bridge arms so as to eliminate the asymmetry of bridge arm current and the fluctuation of direct current caused by the faults of a plurality of converter valve submodules. The technical scheme has the following effects:
the state information of the converter valve sub-modules in each bridge arm is detected in real time, the fault number of the converter valve sub-modules in the fault state is obtained, the number of the converter valve sub-modules put into each bridge arm is corrected by combining the current direction of the bridge arm, so that the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the asymmetry of the bridge arms due to the faults of the converter valve sub-modules are eliminated, and the stability and the safety of system operation are improved.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.
Claims (10)
1. An MMC-HCDC bridge arm asymmetric operation fault-tolerant control method comprises the following steps: direct current utmost point accuse module and valve control module, its characterized in that includes the following step:
according to the length ofCalculating the initial input quantity N of each bridge arm converter valve submodule by the modulating wave of the flow pole control moduleputin；
Acquiring running state information uploaded by the converter valve submodule;
acquiring the fault number N of the converter valve submodule according to the running state information uploaded by the converter valve submodulefault；
And correcting the initial input quantity of the converter valve sub-modules of each bridge arm according to the fault quantity of the converter valve sub-modules and the current directions of the bridge arms so as to eliminate the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the faults of a plurality of converter valve sub-modules.
2. The MMC-HCDC bridge arm asymmetric operation fault-tolerant control method of claim 1, wherein according to the number N of faults of the converter valve sub-module, the fault tolerance is realizedfaultAnd the initial input quantity N of the current flow directions of the bridge arms to the converter valve sub-modules of each bridge armputinPerforming a correction comprising:
when the current direction of the bridge arm is the charging direction, correcting the input quantity of the converter valve sub-modules to the initial input quantity NputinAnd the number of faults NfaultSumming;
when the current direction of the bridge arm is the discharging direction, keeping the input quantity of the converter valve sub-modules to be the initial input quantity Nputin。
3. The MMC-HCDC bridge arm asymmetric operation fault-tolerant control method of claim 2, wherein the input quantity of the converter valve sub-modules is corrected to the initial input quantity NputinAnd the number of faults NfaultAnd (c) a sum comprising:
acquiring and sequencing capacitor voltage values;
inputting corresponding N according to the sequence of the capacitor voltage values from small to largeputin+NfaultEach converter valve sub-module.
4. The MMC-HCDC bridge arm asymmetric operation fault-tolerant control method of claim 2, wherein the input number N of converter valve sub-modules isputinMaintaining at the initial plunge amount, comprising:
acquiring and sequencing capacitor voltage values;
inputting corresponding N according to the sequence of the capacitor voltage values from large to smallputinEach converter valve sub-module.
5. The MMC-HCDC bridge arm asymmetric operation fault-tolerant control method of claim 1, wherein the number N of faults of the converter valve sub-module is obtained according to operation state information uploaded by the converter valve sub-modulefaultThe method comprises the following steps:
when the bridge arm converter valve sub-module fails, controlling the converter valve sub-module in a failure state to close a bypass through a bypass switch;
uploading the capacitor voltage value of the converter valve submodule in a fault state to the valve control module, and uploading the state information of the converter valve submodule to the valve control module;
obtaining the fault number N of the converter valve sub-modulefault。
6. The utility model provides a fault-tolerant control device of MMC-HCDC bridge arm asymmetric operation trouble, MMC-HCDC bridge arm control system includes: direct current utmost point accuse module and valve control module, its characterized in that includes:
a first calculation module for calculating the initial input quantity N of each bridge arm converter valve submodule according to the modulation wave of the direct current pole control moduleputin；
The first acquisition module is used for acquiring the running state information uploaded by the converter valve submodule;
a second obtaining module, configured to obtain the event of the converter valve sub-module according to the operation status information uploaded by the converter valve sub-moduleNumber of barriers Nfault；
And the control module corrects the initial input quantity of the converter valve sub-modules of each bridge arm according to the fault quantity of the converter valve sub-modules and the current directions of the bridge arms so as to eliminate the asymmetry of bridge arm currents and the fluctuation of direct currents caused by the faults of the converter valve sub-modules.
7. The MMC-HCDC bridge arm asymmetric operation fault-tolerant control method of claim 6, wherein the control module comprises:
a first control unit for correcting the input number of the converter valve sub-modules to the initial input number N when the current direction of the bridge arm is a charging directionputinAnd the number of faults NfaultSumming;
a second control unit for maintaining the input number of the converter valve submodules to the initial input number N when the current direction of the bridge arm is the discharging directionputin。
8. The MMC-HCDC bridge arm asymmetric operation fault tolerant control method of claim 7, wherein the first control unit comprises:
the first acquiring subunit is used for acquiring and sequencing the capacitor voltage values;
a first control subunit for inputting corresponding N according to the sequence of the capacitor voltage values from small to largeputin+NfaultEach converter valve sub-module.
9. The MMC-HCDC bridge arm asymmetric operation fault tolerant control method of claim 7, wherein the first control unit comprises:
the second acquisition subunit is used for acquiring and sequencing the capacitor voltage values;
a second control subunit for inputting corresponding N according to the sequence of the capacitor voltage values from large to smallputinA current conversionA valve submodule.
10. The MMC-HCDC bridge arm asymmetric operation fault-tolerant control method of claim 1, wherein the second obtaining module comprises:
the third control unit is used for controlling the converter valve sub-module in a fault state to close a bypass through a bypass switch when the bridge arm converter valve sub-module fails;
the data transmission unit is used for uploading the capacitance voltage value of the converter valve sub-module in a fault state to the valve control module and uploading the state information of the converter valve sub-module to the valve control module;
a third obtaining unit for obtaining the fault number N of the converter valve submodulefault。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011527736.6A CN112688547B (en) | 2020-12-22 | 2020-12-22 | Fault-tolerant control method and device for asymmetric operation fault of MMC-HVDC bridge arm |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011527736.6A CN112688547B (en) | 2020-12-22 | 2020-12-22 | Fault-tolerant control method and device for asymmetric operation fault of MMC-HVDC bridge arm |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112688547A true CN112688547A (en) | 2021-04-20 |
| CN112688547B CN112688547B (en) | 2022-05-20 |
Family
ID=75450488
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011527736.6A Active CN112688547B (en) | 2020-12-22 | 2020-12-22 | Fault-tolerant control method and device for asymmetric operation fault of MMC-HVDC bridge arm |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112688547B (en) |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140002933A1 (en) * | 2011-03-16 | 2014-01-02 | State Grid Corporation Of China | Modular multilevel converter valve protection method |
| CN104917415A (en) * | 2014-03-13 | 2015-09-16 | 国家电网公司 | DC fault ride-through control method for hybrid modular multilevel converter |
| EP2961057A1 (en) * | 2014-06-26 | 2015-12-30 | Alstom Technology Ltd. | Voltage source converter and control thereof |
| US20160261180A1 (en) * | 2015-03-05 | 2016-09-08 | Ge Energy Power Conversion Technology Ltd | GE Energy Power Conversion Technology Ltd |
| CN106787885A (en) * | 2017-02-27 | 2017-05-31 | 中国石油大学(华东) | A kind of MMC System Fault Tolerance control methods of irredundant submodule |
| US20180241321A1 (en) * | 2015-08-18 | 2018-08-23 | General Electric Technology Gmbh | Voltage source converter and control thereof |
| CN109586589A (en) * | 2018-11-19 | 2019-04-05 | 许继集团有限公司 | A kind of MMC, submodule put into a number calculating method, investment method and device |
| CN109830943A (en) * | 2019-01-02 | 2019-05-31 | 华中科技大学 | A kind of flexible direct current electric network fault Current limited Control system, method and application |
| CN111211675A (en) * | 2020-02-24 | 2020-05-29 | 全球能源互联网研究院有限公司 | Submodule redundancy configuration method and system of modular multilevel converter |
| CN112039361A (en) * | 2020-09-04 | 2020-12-04 | 华北电力大学（保定） | MMC sub-module and MMC latch-free low-voltage fault ride-through method applying same |
-
2020
- 2020-12-22 CN CN202011527736.6A patent/CN112688547B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140002933A1 (en) * | 2011-03-16 | 2014-01-02 | State Grid Corporation Of China | Modular multilevel converter valve protection method |
| CN104917415A (en) * | 2014-03-13 | 2015-09-16 | 国家电网公司 | DC fault ride-through control method for hybrid modular multilevel converter |
| EP2961057A1 (en) * | 2014-06-26 | 2015-12-30 | Alstom Technology Ltd. | Voltage source converter and control thereof |
| US20160261180A1 (en) * | 2015-03-05 | 2016-09-08 | Ge Energy Power Conversion Technology Ltd | GE Energy Power Conversion Technology Ltd |
| US20180241321A1 (en) * | 2015-08-18 | 2018-08-23 | General Electric Technology Gmbh | Voltage source converter and control thereof |
| CN106787885A (en) * | 2017-02-27 | 2017-05-31 | 中国石油大学(华东) | A kind of MMC System Fault Tolerance control methods of irredundant submodule |
| CN109586589A (en) * | 2018-11-19 | 2019-04-05 | 许继集团有限公司 | A kind of MMC, submodule put into a number calculating method, investment method and device |
| CN109830943A (en) * | 2019-01-02 | 2019-05-31 | 华中科技大学 | A kind of flexible direct current electric network fault Current limited Control system, method and application |
| CN111211675A (en) * | 2020-02-24 | 2020-05-29 | 全球能源互联网研究院有限公司 | Submodule redundancy configuration method and system of modular multilevel converter |
| CN112039361A (en) * | 2020-09-04 | 2020-12-04 | 华北电力大学（保定） | MMC sub-module and MMC latch-free low-voltage fault ride-through method applying same |
Non-Patent Citations (2)
| Title |
|---|
| SEOK-MIN KIM，ET AL: "Fault-Tolerant Control Scheme for Modular Multilevel", 《2018 IEEE APPLIED POWER ELECTRONICS CONFERANCE AND EXPOSITION》 * |
| 倪斌业，等: "柔性直流电网紧急限流控制策略研究", 《中国电机工程学报》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112688547B (en) | 2022-05-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ren et al. | Interfacing issues in real-time digital simulators | |
| JP6545425B1 (en) | Power converter | |
| CN106533227A (en) | Modularization multi-level converter redundancy fault-tolerant control method | |
| CN106953347A (en) | Hybrid modularization multi-level converter direct-current short circuit fault recovery method and device | |
| CN110995115A (en) | Improved three-dimensional space vector modulation method and system | |
| Bhesaniya et al. | Norton equivalent modeling of current source MMC and its use for dynamic studies of back-to-back converter system | |
| JPWO2021130911A1 (en) | Power converter | |
| WO2020250358A1 (en) | Power conversion device | |
| CN115954866A (en) | Low-voltage ride-through control method and device for two-stage grid-connected photovoltaic inverter | |
| CN109586589B (en) | MMC and submodule investment number calculation method, investment method and device | |
| CN107465360B (en) | Harmonic circulating current eliminating method and device for modular multilevel converter | |
| CN111478352B (en) | Control method and device for flexible direct current transmission system and storage medium | |
| CN112688547B (en) | Fault-tolerant control method and device for asymmetric operation fault of MMC-HVDC bridge arm | |
| CN115313823A (en) | Method and device for controlling dynamic hot standby redundancy switching of direct-current transformer | |
| Martinez-Rodrigo et al. | Calculation of the number of modules and the switching frequency of a modular multilevel converter using near level control | |
| CN114759817B (en) | Seamless open-circuit fault model prediction fault-tolerant control method suitable for cascading full-bridge NPC inverter | |
| CN105119477B (en) | Modular multilevel converter system DC bipolar short-circuit current suppressing method | |
| CN112115660A (en) | Bridge arm equivalent circuit, high-voltage direct-current transmission system and simulation method thereof | |
| CN104811063A (en) | Modular multilevel converter control method based on multicore controller technology | |
| CN115549238A (en) | Chain type energy storage system in-phase SOC (state of charge) equalization method and system based on carrier phase shift modulation | |
| Sun et al. | Open-circuit fault diagnosis and fault-tolerant control with sequential indirect model predictive control for modular multilevel converters | |
| CN112366657A (en) | Control method and device for blocking fault of isolated direct-current converter based on energy storage | |
| Meng et al. | An enhanced average value model of modular multilevel converter for accurate representation of converter blocking operation | |
| Arnold et al. | Modelling rectifier loads for a multi-machine transient-stability programme | |
| Abdelsalam et al. | A fault tolerant control technique for Hybrid modular multi-level converters with fault detection capability |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |