CN116613961A - Mixed MMC simulation model and method for simulating locking state of bridge arm - Google Patents
Mixed MMC simulation model and method for simulating locking state of bridge arm Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
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- H02M1/0012—Control circuits using digital or numerical techniques
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- G06F30/367—Design verification, e.g. using simulation, simulation program with integrated circuit emphasis [SPICE], direct methods or relaxation methods
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
- H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
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Abstract
The invention discloses a mixed MMC simulation model and a method for simulating a bridge arm locking state, wherein the simulation model comprises a current path and a capacitor branch, and the current path comprises a controlled voltage source u for simulating the bridge arm voltage hb And u fb The method comprises the steps of carrying out a first treatment on the surface of the The capacitive branch comprises a half-bridge branch and a full-bridge branch, and the half-bridge branch comprises a controlled current source i for simulating bridge arm current hb Equivalent capacitance C of bridge arm capacitance hb The method comprises the steps of carrying out a first treatment on the surface of the The full bridge branch comprises a controlled current source i for simulating the bridge arm current fb Equivalent capacitance C of bridge arm capacitance fb The method comprises the steps of carrying out a first treatment on the surface of the Controlled voltage source u hb And a bridge arm average value model of a half-bridge branch equivalent to a half-bridge MMC, and a controlled voltage source u fb And the half-bridge branch is equivalent to a bridge arm average model of a full-bridge MMC; bridge arm of half-bridge MMC and full-bridge MMC is flatThe mean model forms a bridge arm equivalent model of the mixed MMC together; the invention can accurately simulate the characteristics of the mixed MMC detailed model in a locking state, greatly improve the simulation efficiency and greatly reduce the simulation burden of the model.
Description
Technical Field
The invention relates to a hybrid MMC simulation model and method for simulating a bridge arm locking state, and belongs to the technical field of power systems.
Background
With the development of flexible direct current transmission technology, the topology structure of the modular multilevel converter (modular multilevel converter, MMC) is also derived into a plurality of forms, mainly including half-bridge MMC, full-bridge MMC, hybrid MMC and the like. Compared with the half-bridge type MMC and the full-bridge type MMC, the hybrid type MMC has the direct current fault ride through capacity and is lower in economical aspect than the full-bridge type MMC. On one hand, the cost of the flexible direct current transmission system in the aspect of expensive cables is reduced, on the other hand, the system failure rate is reduced considerably, and the development prospect and the development space of the flexible direct current transmission technology are widened. However, according to the number ratio of the half-bridge sub-modules to the Quan Qiaozi modules in the bridge arm, the number of the power semiconductor devices adopted by the hybrid MMC is one to two times that adopted by the half-bridge MMC, which results in high loss of the hybrid MMC, and a large number of power semiconductor devices bring a larger burden to electromagnetic transient simulation. In this respect, researchers have proposed many fast simulation methods, such as a general equivalent model, an average model, and a bridge arm average model, which are more commonly used. The general equivalent model simplification method is characterized in that the admittance matrix of the reduced order model is used for cutting off the connection between all sub-modules in the bridge arm and independently simulating the capacitive charging and discharging action process of all the sub-modules, and the method can realize quick simulation to a certain extent but still can not reach the required ideal simulation speed; the average value model adopts six controllable voltage sources to replace six bridge arms, the simulation speed is obviously improved, and the charging and discharging processes of the capacitors of the submodules can be well simulated, but the dynamic characteristics of the voltages of the capacitors in the bridge arms are difficult to embody, the application range is narrow, and the simulation speed is accurate only when the capacitance value of the submodules is larger; the bridge arm average model inherits the advantages of the first two simulation models, can embody the dynamic characteristics of the charge and discharge process and the capacitor voltage of the internal capacitor of the bridge arm, ensures high accuracy, has extremely fast simulation efficiency, and is a mainstream fast simulation method at present. However, when the bridge arm locking condition occurs, the bridge arm average value model cannot simulate the action of the anti-parallel diode to be the bridge arm capacitance follow current, and only the bridge arm is disconnected, in this case, the current in the bridge arm is suddenly changed and falls to zero, so that the voltage and current parameters of other elements of the system are affected, the waveform and the actual waveform of the system are different, and the dynamic characteristic of the MMC in the locking state cannot be simulated correctly.
Disclosure of Invention
The invention aims to overcome the defects in the prior art, and provides a hybrid MMC simulation model and a method for simulating a locking state of a bridge arm, which can accurately simulate transient processes and dynamic responses of the hybrid MMC in the locking state and can realize quick simulation indexes of the hybrid MMC.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
in a first aspect, the present invention provides a hybrid MMC simulation model for simulating a latching state of a bridge arm, the simulation model comprising a current path and a capacitive branch, the current path comprising a receptor for simulating a voltage of the bridge armVoltage control source u hb And u fb For controlling a controlled voltage source u hb And u fb A first control component in a conducting state; the capacitive branch comprises a half-bridge branch and a full-bridge branch, wherein the half-bridge branch comprises a controlled current source i for simulating bridge arm current hb Equivalent capacitance C of bridge arm capacitance hb For controlling a controlled current source i hb A second control component in an on state; the full-bridge branch comprises a controlled current source i for simulating bridge arm current fb Equivalent capacitance C of bridge arm capacitance fb For controlling a controlled current source i fb A third control component in an on state; the controlled voltage source u hb And a bridge arm average model of the half-bridge branch equivalent to the half-bridge MMC, wherein the controlled voltage source u fb And the half-bridge branch is equivalent to a bridge arm average model of a full-bridge MMC; and the bridge arm average value models of the half-bridge MMC and the full-bridge MMC jointly form a bridge arm equivalent model of the mixed MMC.
Optionally, the controlled voltage source u hb And u fb Connected in series, the controlled voltage source u hb Is connected to the positive pole of the bridge arm, the controlled voltage source u fb Is connected to the negative pole of the bridge arm; the first control component comprises a diode VT 1 、VT 2 、VT 3 、VT 4 、VT 5 And circuit breaker BRK 1 、BRK 2 、BRK 3 、BRK 4 、BRK 5 The method comprises the steps of carrying out a first treatment on the surface of the The diode VT 1 Is connected to the negative terminal of the controlled voltage source u hb Is connected with the anode of the diode VT 1 Is passed through the circuit breaker BRK 1 And a controlled voltage source u hb Is connected with the negative electrode of the battery; the diode VT 2 Is connected to the negative terminal of the controlled voltage source u hb Is a cathode of (1) and diode VT 3 Is connected with the positive terminal of the diode VT 2 Is passed through the circuit breaker BRK 2 And a controlled voltage source u fb Is a cathode of (1) and diode VT 4 Is connected with the positive end of the connecting rod; the diode VT 3 Is connected to the negative terminal of the controlled voltage source u fb Is a positive electrode and diode VT 5 Is connected with the negative end of the battery; the diode VT 4 Is passed through the negative terminal of the breaker BRK 5 And diode VT 5 Is connected with the positive end of the connecting rod; the circuit breaker BRK 3 And diode VT 3 Parallel connection, the circuit breaker BRK 4 And diode VT 4 Connected in parallel.
Optionally, the controlled current source i hb And equivalent capacitance C hb Connected in parallel, the controlled current source i hb The positive pole and the negative pole of the bridge arm are connected with the positive pole and the negative pole of the bridge arm; the second control component comprises a diode VT 11 And circuit breaker BRK 11 Said diode VT 11 Is connected to the negative terminal of the controlled current source i hb Is connected with the anode of the diode VT 11 Is passed through the circuit breaker BRK 11 With a controlled current source i hb Is connected to the negative electrode of the battery.
Optionally, the controlled current source i fb The positive pole and the negative pole of the bridge arm are connected with the positive pole and the negative pole of the bridge arm; the third control component comprises a diode VT 12 、VT 13 、VT 14 、VT 15 And circuit breaker BRK 12 、BRK 13 、BRK 14 、BRK 15 The method comprises the steps of carrying out a first treatment on the surface of the The diode VT 12 Is connected to the negative terminal of the controlled current source i fb Is a positive electrode and diode VT 13 Is connected with the positive terminal of the diode VT 12 Is connected with the positive terminal of the diode VT 15 Is connected with the positive end of the connecting rod; the diode VT 13 Negative terminal of (2) and diode VT 14 Is connected to the negative terminal of the diode VT 14 Is passed through the circuit breaker BRK 14 And diode VT 15 Is connected to the negative terminal of the controlled current source i fb Is connected with the negative electrode of the battery; the equivalent capacitance C fb Is connected to the diode VT at both ends 14 Negative terminal and diode VT 15 Is connected with the positive end of the circuit breaker BRK 13 And diode VT 13 Parallel connection, the circuit breaker BRK 15 And diode VT 15 And are connected in parallel.
Optionally, the controlled voltage source u hb And u fb The method meets the following conditions:
u hb ＝N on *u C.tot /N
u fb ＝N o ′ n *u ′ C.tot /N ′
wherein N is on 、N o ′ n For the number of all conducting half-bridge sub-modules and Quan Qiaozi modules in one bridge arm, u C.tot 、u ′ C.tot Is the total voltage of the bridge arm when all the half-bridge submodules and the full-bridge submodules in the bridge arm are conducted, N, N ′ The number of all half-bridge submodules and Quan Qiaozi modules in one bridge arm;
the equivalent capacitance C hb And C fb The method meets the following conditions:
C hb ＝C 0 /N
C fb ＝C 0 ′ /N ′
wherein C is 0 、C 0 ′ Capacitance values for one half-bridge sub-module and Quan Qiaozi module;
the controlled current source i hb And i fb The method meets the following conditions:
i hb ＝N*i arm /N on
i fb ＝N ′ *i ′ arm /N o ′ n
wherein i is arm 、i ′ arm The bridge arm current is the bridge arm current when all the half-bridge submodules and the full-bridge submodules in the bridge arm are conducted.
In a second aspect, the present invention provides a hybrid MMC simulation method for simulating a bridge arm locking state, where the simulation is performed by using the hybrid MMC simulation model for simulating a bridge arm locking state as set forth in claim 5, where the simulation conditions include:
the first simulation working condition is as follows:
circuit breaker BRK for driving current path 1 、BRK 2 、BRK 5 Breaking, circuit breaker BRK 3 、BRK 4 Circuit breaker BRK for closing and driving capacitive branch 11 、BRK 13 、BRK 15 Breaking, circuit breaker BRK 12 、BRK 14 Closing, and simulating the normal working state of the mixed MMC;
the second simulation working condition is as follows:
circuit breaker BRK for driving current path 1 、BRK 2 、BRK 5 Closing, breaker BRK 3 、BRK 4 Circuit breaker BRK for breaking and driving capacitive branch 11 、BRK 13 、BRK 15 Closing, breaker BRK 12 、BRK 14 The open, simulated hybrid MMC latch-up condition.
Compared with the prior art, the invention has the beneficial effects that:
according to the mixed MMC simulation model and method for simulating the locking state of the bridge arm, provided by the invention, through improving the structure of the bridge arm average model and adding the circuit breaker, the diode and the additional control strategy, the purpose of accurately simulating the normal working state of the mixed MMC and the bridge arm working characteristic under the locking state is realized, and the defect of the existing rapid simulation method on researching the locking state of the bridge arm of the mixed MMC under the condition of simulating the short circuit fault of the alternating current side is overcome. The invention can accurately simulate the characteristics of the mixed MMC detailed model in a locking state, greatly improve the simulation efficiency and greatly reduce the simulation burden of the model.
Drawings
FIG. 1 is a diagram illustrating a current path structure of a hybrid MMC simulation model according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a capacitor branch circuit of a hybrid MMC simulation model according to an embodiment of the present invention;
fig. 3 is a schematic topology diagram of a bridge arm average model according to a first embodiment of the present invention;
fig. 4 is a schematic structural diagram of a single-ended hybrid MMC-HVDC testing system in accordance with an embodiment of the present invention;
fig. 5 is a simulation waveform diagram of a half-bridge submodule to full-bridge submodule input ratio in a model bridge arm according to an embodiment of the present invention;
fig. 6 is a waveform diagram of simulation of output voltages of a half-bridge portion and a full-bridge portion in a model bridge arm according to a first embodiment of the present invention;
fig. 7 is a waveform diagram of capacitor voltage simulation in a model bridge arm according to an embodiment of the present invention.
Detailed Description
The invention is further described below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present invention, and are not intended to limit the scope of the present invention.
Embodiment one:
1-2, the invention provides a hybrid MMC simulation model for simulating the locking state of a bridge arm, wherein the simulation model comprises a current path and a capacitor branch, and the current path comprises a controlled voltage source u for simulating the voltage of the bridge arm hb And u fb For controlling a controlled voltage source u hb And u fb A first control component in a conducting state; the capacitive branch comprises a half-bridge branch and a full-bridge branch, and the half-bridge branch comprises a controlled current source i for simulating bridge arm current hb Equivalent capacitance C of bridge arm capacitance hb For controlling a controlled current source i hb A second control component in an on state; the full bridge branch comprises a controlled current source i for simulating the bridge arm current fb Equivalent capacitance C of bridge arm capacitance fb For controlling a controlled current source i fb A third control component in an on state; controlled voltage source u hb And a bridge arm average value model of a half-bridge branch equivalent to a half-bridge MMC, and a controlled voltage source u fb And the half-bridge branch is equivalent to a bridge arm average model of a full-bridge MMC; the bridge arm average value models of the half-bridge MMC and the full-bridge MMC jointly form a bridge arm equivalent model of the mixed MMC.
In particular, a controlled voltage source u hb And u fb Connected in series, a controlled voltage source u hb Is connected to the positive pole of the bridge arm, and is controlled by a voltage source u fb Is connected to the negative pole of the bridge arm; the first control component comprises a diode VT 1 、VT 2 、VT 3 、VT 4 、VT 5 And circuit breaker BRK 1 、BRK 2 、BRK 3 、BRK 4 、BRK 5 The method comprises the steps of carrying out a first treatment on the surface of the Diode VT 1 Is connected to the negative terminal of the controlled voltage source u hb Is connected with the positive electrode of the diode VT 1 Is passed through the circuit breaker BRK 1 And a controlled voltage source u hb Is connected with the negative electrode of the battery; diode VT 2 Is connected to the negative terminal of the controlled voltage source u hb Is a cathode of (1) and diode VT 3 Is connected with the positive terminal of the diode VT 2 Is passed through the circuit breaker BRK 2 And a controlled voltage source u fb Is a cathode of (1) and diode VT 4 Is connected with the positive end of the connecting rod; diode VT 3 Is connected to the negative terminal of the controlled voltage source u fb Is a positive electrode and diode VT 5 Is connected with the negative end of the battery; diode VT 4 Is passed through the negative terminal of the circuit breaker BRK 5 And diode VT 5 Is connected with the positive end of the connecting rod; circuit breaker BRK 3 And diode VT 3 Parallel connection, circuit breaker BRK 4 And diode VT 4 Connected in parallel.
In particular, a controlled current source i hb And equivalent capacitance C hb Parallel connection, controlled current source i hb The positive pole and the negative pole of the bridge arm are connected with the positive pole and the negative pole of the bridge arm; the second control component comprises a diode VT 11 And circuit breaker BRK 11 Diode VT 11 Is connected to the negative terminal of the controlled current source i hb Is connected with the positive electrode of the diode VT 11 Is passed through the circuit breaker BRK 11 With a controlled current source i hb Is connected to the negative electrode of the battery.
In particular, a controlled current source i fb The positive pole and the negative pole of the bridge arm are connected with the positive pole and the negative pole of the bridge arm; the third control component comprises a diode VT 12 、VT 13 、VT 14 、VT 15 And circuit breaker BRK 12 、BRK 13 、BRK 14 、BRK 15 The method comprises the steps of carrying out a first treatment on the surface of the Diode VT 12 Is connected to the negative terminal of the controlled current source i fb Is a positive electrode and diode VT 13 Is connected with the positive terminal of the diode VT 12 Is connected with the positive terminal of the diode VT 15 Is connected with the positive end of the connecting rod; diode VT 13 Negative terminal of (2) and diode VT 14 Is connected with the negative terminal of the diode VT 14 Is passed through the circuit breaker BRK 14 And diode VT 15 Is connected to the negative terminal of the controlled current source i fb Is connected with the negative electrode of the battery; equivalent capacitance C fb Is connected to the diode VT at both ends 14 Negative terminal and diode VT 15 Is the positive terminal of the circuit breaker BRK 13 And diode VT 13 Parallel circuit breaker BRK 15 And diode VT 15 And are connected in parallel.
As shown in fig. 3, the bridge arm average model can embody the dynamic characteristics of the charge and discharge process of the internal capacitance of the bridge arm and the capacitance voltage, and has extremely fast simulation efficiency while ensuring high accuracy. The bridge arm average model consists of two parts, namely a main path and a capacitor branch, wherein the main path is formed by a controlled voltage source u armeq The capacitor branch is formed by a controlled current source i Ceq And a bridge arm equivalent capacitance C eq Constructing; applied to the present embodiment:
the controlled voltage source u hb And u fb The method meets the following conditions:
u hb ＝N on *u C.tot /N
u fb ＝N o ′ n *u ′ C.tot /N ′
wherein N is on 、N o ′ n For the number of all conducting half-bridge sub-modules and Quan Qiaozi modules in one bridge arm, u C.tot 、u ′ C.tot Is the total voltage of the bridge arm when all the half-bridge submodules and the full-bridge submodules in the bridge arm are conducted, N, N ′ The number of all half-bridge submodules and Quan Qiaozi modules in one bridge arm;
the equivalent capacitance C hb And C fb The method meets the following conditions:
C hb ＝C 0 /N
C fb ＝C 0 ′ /N ′
wherein C is 0 、C 0 ′ Capacitance values for one half-bridge sub-module and Quan Qiaozi module;
the controlled current source i hb And i fb The method meets the following conditions:
i hb ＝N*i arm /N on
i fb ＝N ′ *i ′ arm /N o ′ n
wherein i is arm 、i ′ arm The bridge arm current is the bridge arm current when all the half-bridge submodules and the full-bridge submodules in the bridge arm are conducted.
Embodiment two:
based on the first embodiment, the embodiment of the invention provides a hybrid MMC simulation method for simulating a locking state of a bridge arm, wherein simulation working conditions comprise:
the first simulation working condition is as follows:
circuit breaker BRK for driving current path 1 、BRK 2 、BRK 5 Breaking, circuit breaker BRK 3 、BRK 4 Circuit breaker BRK for closing and driving capacitive branch 11 、BRK 13 、BRK 15 Breaking, circuit breaker BRK 12 、BRK 14 Closing, and simulating the normal working state of the mixed MMC;
the second simulation working condition is as follows:
circuit breaker BRK for driving current path 1 、BRK 2 、BRK 5 Closing, breaker BRK 3 、BRK 4 Circuit breaker BRK for breaking and driving capacitive branch 11 、BRK 13 、BRK 15 Closing, breaker BRK 12 、BRK 14 The open, simulated hybrid MMC latch-up condition.
By applying additional control strategies to the circuit breakers in the equivalent model, the simulation of the characteristics of the detailed switch model in the lockout state can be achieved. The equivalent resistance value in the circuit is half of the equivalent resistance value when the anti-parallel diode is conducted, and the hybrid MMC operates in a locking state at the starting time or during the fault.
As shown in fig. 4, in order to verify the simulation method, the embodiment of the invention provides a single-ended hybrid MMC-HVDC test system, wherein a single bridge arm comprises N full-bridge sub-modules and N-N half-bridge sub-modules. When the flexible direct current transmission system fails, the converter station is switched to a locking state, and the condition of a certain end system corresponding to the failure point is generally only needed to be analyzed, and the simulation result under the test can be obtained in different test systems; the simulation parameters of the test system used in fig. 4 are shown in table 1, and the test simulation model starts to run from 0s to 4 s. The simulation step length of the model is set to 20 mu s, the system fault is set to be a direct current side short circuit fault, the occurrence time is 1s, and the duration is 0.3s. The time for the system to switch from the normal state to the lockout state is set to 1.01s, and the lockout end time is set to 1.35s. Under the condition of different numbers of bridge arm submodules, the simulation actual time length of the model is compared with the simulation actual time length of the detailed model, and the result is shown in a table 2, wherein the simulation time length of the model is basically unchanged in the process that the number of the submodules is changed from 8 to 40, the simulation time length of the detailed model is obviously increased, and when the number of the submodules is 40, the simulation load of the actual model is greatly increased, and the applicability is reduced. This demonstrates that the method of the present invention can significantly improve the simulation speed.
Table 1 simulation system parameters
| Parameters (parameters) | Variable name | Numerical value |
| Rated voltage of AC side voltage source | U ac | 60kV |
| Rated voltage of DC side voltage source | U dc | 120kV |
| DC side resistor | R dc | 0.05Ω |
| DC side inductor | L dc | 0.01H |
| Number of half-bridge submodules in a single bridge arm | N h | 4 pieces of |
| Number of full bridge submodules in a single bridge arm | N f | 8 pieces of |
| Bridge arm resistor | R a | 1.0Ω |
| Bridge arm inductance | L a | 0.024H |
| Capacitance value of sub-module | C 0 | 9000μF |
| Sub-module voltage | U SM | 10kV |
Table 2 comparison of actual simulation time of two models
And when the number of the bridge arm half-bridge submodules is set to be 4 and the number of the full-bridge submodules is set to be 8, observing simulation results in the bridge arm of the model, wherein the selected waveform observation period is 0.9s-2s, and waveform comparison diagrams of all parameters are shown in fig. 5-7.
Fig. 5 is a simulation waveform diagram of the input ratio of the half-bridge submodule to the full-bridge submodule in the model bridge arm of the present invention. Under normal working conditions, according to the action of a modulation wave, the full-bridge submodule investment and the half-bridge submodule investment are both in normal working conditions, the full-bridge investment ratio is between-1 and 1, the half-bridge investment ratio is between 0 and 1, the direct-current side short-circuit fault investment is carried out when the half-bridge is operated for 1s, the corresponding breaker action in an equivalent circuit is controlled, the half-bridge submodule part investment is observed to be 0 under the action of locking, the full-bridge submodule part investment is 1, the mixed MMC detailed switch model bridge arm submodule investment condition is met when the direct-current side short-circuit fault is met, and after the locking is released for 1.35s, the system returns to the normal working condition after 0.65s, so that the invention can accurately simulate the submodule investment and bypass action of an actual model under the additional control action.
Fig. 6 is a waveform diagram of simulation of output voltages of a half-bridge part and a full-bridge part in a model bridge arm of the invention. Under normal working condition, the output voltage of the controlled voltage source of the half-bridge part and the full-bridge part in the current path is obtained according to the product of the modulation ratio and the equivalent capacitance voltage. When the system runs to 1s, the direct current side short circuit fault is input, the corresponding breaker action in the equivalent circuit is controlled, the short circuit action of the diode in the half-bridge part can be observed, the output voltage is 0, at the moment, the full-bridge part in the bridge arm is 120kV according to the conduction action of the H bridge, after 1.35s locking is released, the system is restored to the normal running state after 0.65s, and the system can accurately simulate the dynamic characteristics of the output voltage of the bridge arm of the detailed switch model under the additional control action.
Fig. 7 is a waveform diagram of a simulation of capacitance and voltage in a model bridge arm of the present invention. And the equivalent capacitance simulates the sum of all capacitance equivalents of N sub-modules in a single bridge arm of the detailed switch model. In a normal working state, the bridge arm capacitor voltage is the product of the single capacitor voltage and the number of the submodules. When the operation is carried out for 1s, the input of the direct current side short circuit fault is carried out, the action of the corresponding circuit breaker in the equivalent circuit is controlled, the short circuit effect of the diode in the half-bridge part can be observed, the voltage of the half-bridge equivalent capacitor is 0, the output voltage of the full-bridge part is 120kV according to the conduction effect of the H bridge, and the full-bridge output voltage in figure 6 is kept at one to one. After 1.35s of locking is released, the system is restored to a normal running state after 0.65s, and the invention can correctly simulate the bridge arm voltage dynamic characteristics of the bridge arm of the detailed switch model under the additional control action.
According to the scheme, the single-ended hybrid MMC-HVDC simulation model is constructed to verify the accuracy and effectiveness of the method, and the simulation result verification is in the error allowable range through observing the dynamic characteristics of the equivalent circuit output parameters in the bridge arm under the locking state, so that the method can prove that the normal working state and the locking state of the actual model are correctly simulated.
It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention 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 invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations 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.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and variations could be made by those skilled in the art without departing from the technical principles of the present invention, and such modifications and variations should also be regarded as being within the scope of the invention.
Claims (6)
1. A hybrid MMC simulation model for simulating a locking state of a bridge arm is characterized in that the simulation model comprises a current path and a capacitor branch, and the current path comprises a controlled voltage source u for simulating the voltage of the bridge arm hb And u fb For controlling a controlled voltage source u hb And u fb A first control component in a conducting state; the capacitive branch comprises a half-bridge branch and a full-bridge branch, wherein the half-bridge branch comprises a controlled current source i for simulating bridge arm current hb Equivalent capacitance C of bridge arm capacitance hb For controlling a controlled current source i hb A second control component in an on state; the full-bridge branch comprises a controlled current source i for simulating bridge arm current fb Equivalent capacitance C of bridge arm capacitance fb For controlling a controlled current source i fb A third control component in an on state; the controlled voltage source u hb And half-bridge branches are equivalent to halfThe controlled voltage source u is a bridge arm average value model of a bridge type MMC fb And the half-bridge branch is equivalent to a bridge arm average model of a full-bridge MMC; and the bridge arm average value models of the half-bridge MMC and the full-bridge MMC jointly form a bridge arm equivalent model of the mixed MMC.
2. The hybrid MMC simulation model of modeling arm latch-up condition of claim 1, wherein the controlled voltage source u hb And u fb Connected in series, the controlled voltage source u hb Is connected to the positive pole of the bridge arm, the controlled voltage source u fb Is connected to the negative pole of the bridge arm; the first control component comprises a diode VT 1 、VT 2 、VT 3 、VT 4 、VT 5 And circuit breaker BRK 1 、BRK 2 、BRK 3 、BRK 4 、BRK 5 The method comprises the steps of carrying out a first treatment on the surface of the The diode VT 1 Is connected to the negative terminal of the controlled voltage source u hb Is connected with the anode of the diode VT 1 Is passed through the circuit breaker BRK 1 And a controlled voltage source u hb Is connected with the negative electrode of the battery; the diode VT 2 Is connected to the negative terminal of the controlled voltage source u hb Is a cathode of (1) and diode VT 3 Is connected with the positive terminal of the diode VT 2 Is passed through the circuit breaker BRK 2 And a controlled voltage source u fb Is a cathode of (1) and diode VT 4 Is connected with the positive end of the connecting rod; the diode VT 3 Is connected to the negative terminal of the controlled voltage source u fb Is a positive electrode and diode VT 5 Is connected with the negative end of the battery; the diode VT 4 Is passed through the negative terminal of the circuit breaker BRK 5 And diode VT 5 Is connected with the positive end of the connecting rod; the circuit breaker BRK 3 And diode VT 3 Parallel connection, the circuit breaker BRK 4 And diode VT 4 Connected in parallel.
3. The hybrid MMC simulation model of modeling arm latch-up condition of claim 2, wherein the controlled current source i hb And equivalent capacitance C hb Connected in parallel, the controlled current source i hb Is connected to the bridgePositive and negative poles of the arms; the second control component comprises a diode VT 11 And circuit breaker BRK 11 Said diode VT 11 Is connected to the negative terminal of the controlled current source i hb Is connected with the anode of the diode VT 11 Is passed through the circuit breaker BRK 11 With a controlled current source i hb Is connected to the negative electrode of the battery.
4. The hybrid MMC simulation model of modeling arm latch-up condition of claim 3, wherein the controlled current source i fb The positive pole and the negative pole of the bridge arm are connected with the positive pole and the negative pole of the bridge arm; the third control component comprises a diode VT 12 、VT 13 、VT 14 、VT 15 And circuit breaker BRK 12 、BRK 13 、BRK 14 、BRK 15 The method comprises the steps of carrying out a first treatment on the surface of the The diode VT 12 Is connected to the negative terminal of the controlled current source i fb Is a positive electrode and diode VT 13 Is connected with the positive terminal of the diode VT 12 Is connected with the positive terminal of the diode VT 15 Is connected with the positive end of the connecting rod; the diode VT 13 Negative terminal of (2) and diode VT 14 Is connected to the negative terminal of the diode VT 14 Is passed through the circuit breaker BRK 14 And diode VT 15 Is connected to the negative terminal of the controlled current source i fb Is connected with the negative electrode of the battery; the equivalent capacitance C fb Is connected to the diode VT at both ends 14 Negative terminal and diode VT 15 Is connected with the positive end of the circuit breaker BRK 13 And diode VT 13 Parallel connection, the circuit breaker BRK 15 And diode VT 15 And are connected in parallel.
5. The hybrid MMC simulation model of modeling arm latch-up condition of claim 4, wherein the controlled voltage source u hb And u fb The method meets the following conditions:
u hb ＝N on *u C.tot /N
u fb ＝N o ′ n *u ′ C.tot /N ′
wherein N is on 、N o ′ n For the number of all conducting half-bridge sub-modules and Quan Qiaozi modules in one bridge arm, u C.tot 、u ′ C.tot Is the total voltage of the bridge arm when all the half-bridge submodules and the full-bridge submodules in the bridge arm are conducted, N, N ′ The number of all half-bridge submodules and Quan Qiaozi modules in one bridge arm;
the equivalent capacitance C hb And C fb The method meets the following conditions:
C hb ＝C 0 /N
C fb ＝C 0 ′ /N ′
wherein C is 0 、C 0 ′ Capacitance values for one half-bridge sub-module and Quan Qiaozi module;
the controlled current source i hb And i fb The method meets the following conditions:
i hb ＝N*i arm /N on
i fb ＝N ′ *i ′ arm /N o ′ n
wherein i is arm 、i ′ arm The bridge arm current is the bridge arm current when all the half-bridge submodules and the full-bridge submodules in the bridge arm are conducted.
6. The mixed MMC simulation method for simulating the locking state of the bridge arm is characterized in that the mixed MMC simulation model for simulating the locking state of the bridge arm is adopted for simulation, and the simulation working conditions comprise:
the first simulation working condition is as follows:
circuit breaker BRK for driving current path 1 、BRK 2 、BRK 5 Breaking, circuit breaker BRK 3 、BRK 4 Circuit breaker BRK for closing and driving capacitive branch 11 、BRK 13 、BRK 15 Breaking, circuit breaker BRK 12 、BRK 14 Closing, and simulating the normal working state of the mixed MMC;
the second simulation working condition is as follows:
breaking of drive current pathCircuit breaker BRK 1 、BRK 2 、BRK 5 Closing, breaker BRK 3 、BRK 4 Circuit breaker BRK for breaking and driving capacitive branch 11 、BRK 13 、BRK 15 Closing, breaker BRK 12 、BRK 14 The open, simulated hybrid MMC latch-up condition.
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| CN117040082A (en) * | 2023-10-08 | 2023-11-10 | 国网江苏省电力有限公司电力科学研究院 | M3C converter bridge arm non-invasive precharge method, device, equipment and medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108376992A (en) * | 2018-03-16 | 2018-08-07 | 云南电网有限责任公司 | A kind of mixing submodule MMC equivalent simulation methods |
| CN113191106A (en) * | 2021-05-10 | 2021-07-30 | 中国电力科学研究院有限公司 | Hybrid MMC full-state efficient electromagnetic transient simulation method and system |
| CN114564812A (en) * | 2022-01-11 | 2022-05-31 | 华北电力大学 | Locking equivalent simulation method of double-active-bridge converter |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108376992A (en) * | 2018-03-16 | 2018-08-07 | 云南电网有限责任公司 | A kind of mixing submodule MMC equivalent simulation methods |
| CN113191106A (en) * | 2021-05-10 | 2021-07-30 | 中国电力科学研究院有限公司 | Hybrid MMC full-state efficient electromagnetic transient simulation method and system |
| CN114564812A (en) * | 2022-01-11 | 2022-05-31 | 华北电力大学 | Locking equivalent simulation method of double-active-bridge converter |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117040082A (en) * | 2023-10-08 | 2023-11-10 | 国网江苏省电力有限公司电力科学研究院 | M3C converter bridge arm non-invasive precharge method, device, equipment and medium |
| CN117040082B (en) * | 2023-10-08 | 2024-01-05 | 国网江苏省电力有限公司电力科学研究院 | M3C converter bridge arm non-invasive precharge method, device, equipment and medium |
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