Converter valve capable of finely adjusting turn-off time and dynamic voltage adjusting method thereof

Abstract

The invention provides a converter valve capable of finely adjusting turn-off time and a dynamic voltage regulation method thereof, the converter valve comprises three groups of branches connected in parallel, each group of branches comprises two groups of bridge arms connected in series, and the converter valve is characterized in that the bridge arms comprise a main branch; the main branch comprises a low-voltage large-current controllable unit; the low-voltage large-current controllable unit is used for adjusting the turn-off moment of the low-voltage large-current controllable unit in the current period according to the turn-off voltage peak value in the previous period during steady-state operation in the current period; and adjusting the turn-off moment of the low-voltage large-current controllable unit in the next period according to the turn-off voltage peak value of the current period, so that the turn-off voltage of the low-voltage large-current controllable unit always fluctuates in a preset voltage peak value reference interval range in all periods. Because the turn-off voltage is always kept to fluctuate in the preset voltage peak reference interval range in all periods, the turn-off voltage of the converter valve during steady-state operation is kept at the set interval level.

Description

Technical Field

[0001] The present invention belongs to the technical field of converter valves, and in particular relates to a converter valve with fine-tuning off time and a method for dynamically adjusting voltage thereof. Background Art

[0002] The high-voltage direct current (HVDC) transmission technology based on line commutated converters (LCC-HVDC) has the advantages of large transmission capacity, long distance, high efficiency, low loss and small footprint, and has been widely used. Due to the semi-controlled characteristics of the basic element thyristor, when the AC voltage of the busbar of the LCC-HVDC system receiving-end converter station is distorted or drops due to faults in the AC system, the thyristor cannot be shut down reliably, and the converter fails to commutate, which is also a unique fault form of conventional LCC converters. In order to solve the problem of commutation failure, a new type of controllable line-commutated converter (CLCC) topology with controllable shutdown capability is currently available. It uses thyristors as the main current-carrying elements, and is connected in series with low-voltage, high-current controllable units to form a low-loss current-carrying branch and can realize active current transfer, providing a controllable reverse recovery voltage for the thyristor; the high-voltage, low-current controllable units are connected in parallel, which can take over the current transferred from the thyristor for a short time, provide the thyristor with sufficient reverse voltage time, and can actively shut down the current to realize forced commutation.

[0003] Under different steady-state operating conditions, the arm current and commutation current change rates of the new converter valve are different. The low-voltage, high-current controllable unit needs to be able to meet the operating requirements of the new converter valve with commutation failure immunity and low loss under any operating conditions. Therefore, a terminal voltage dynamic adjustment method is needed.

[0004] In order to improve the ability of the converter valve to resist commutation failure in the first cycle, the voltage at the terminal of the low-voltage, high-current controllable unit must not be too low, otherwise it will not be able to provide sufficient reverse recovery voltage for the main current-passing element thyristor; in order to effectively reduce the steady-state operation loss of the new converter valve, the voltage at the terminal of the low-voltage, high-current controllable unit must not be too high, otherwise it will increase the corresponding resistance and capacitance losses, so it is necessary to ensure that the shutdown voltage during steady-state operation is maintained at the set range level. Summary of the invention

[0005] In order to overcome the deficiencies of the above-mentioned prior art, in the first aspect, the present invention proposes a converter valve with fine-tuning of the shut-off time, wherein the converter valve comprises three groups of parallel branches, each group of branches comprises two groups of bridge arms connected in series, and the bridge arms comprise a main branch; the main branch comprises a low-voltage and high-current controllable unit;

[0006] The low-voltage, high-current controllable unit is used to adjust the shutdown moment of the low-voltage, high-current controllable unit in the current cycle according to the shutdown voltage peak of the previous cycle during steady-state operation of the current cycle; and adjust the shutdown moment of the low-voltage, high-current controllable unit in the next cycle according to the shutdown voltage peak of the current cycle, so that the shutdown voltage of the low-voltage, high-current controllable unit always fluctuates within a preset voltage peak reference interval in all cycles.

[0007] Preferably, the low voltage and high current controllable unit is specifically used for:

[0008] If the turn-off voltage peak value of the previous cycle is higher than the upper limit of the preset voltage peak reference interval, in the current cycle, based on the turn-off time of the previous cycle, the turn-off time of the low-voltage and high-current controllable unit of the current cycle is delayed and adjusted;

[0009] If the shutdown voltage of the current cycle is lower than the lower limit of the preset voltage peak reference interval, the shutdown moment of the low-voltage and high-current controllable unit in the next cycle is adjusted in advance based on the shutdown moment of the current cycle.

[0010] Preferably, the bridge arm further comprises an auxiliary branch connected in parallel with the main branch, wherein the auxiliary branch comprises a high-voltage and low-current controllable unit; the high-voltage and low-current controllable unit is used to actively shut down the current of the auxiliary branch;

[0011] The main branch also includes a main flow unit connected in series with the low-voltage and high-current controllable unit;

[0012] The low-voltage, high-current controllable unit is also used to actively shut down the current of the main branch where the low-voltage, high-current controllable unit is located, so that the current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the branch where the main branch is located is established.

[0013] Preferably, the low-voltage, high-current controllable unit is a first topology structure or a second topology structure;

[0014] The first topological structure includes a lightning arrester, a first capacitor, a first fully-controlled device, a fixed resistor and a first diode, the lightning arrester is connected in parallel with the first capacitor and the first fully-controlled device, the first capacitor is connected in series with the fixed resistor, and the fixed resistor is connected in parallel with the first diode;

[0015] The second topological structure includes a second fully-controlled device, a third fully-controlled device, a second diode, a third diode and a second capacitor. The second fully-controlled device is connected in parallel to the third fully-controlled device, the second fully-controlled device is connected in series to the second diode, the third fully-controlled device is connected in series to the third diode, and the node connected between the cathode of the second diode and the anode of the second fully-controlled device and the node connected between the anode of the third diode and the cathode of the third fully-controlled device are connected to the second capacitor.

[0016] In a second aspect, the present invention also proposes a method for dynamically adjusting the voltage of a converter valve by fine-tuning the closing time, the method comprising:

[0017] When the low-voltage and high-current controllable unit in the converter valve for controlling the fine-tuning of the shut-off time is in steady-state operation in the current cycle, the shut-off moment of the low-voltage and high-current controllable unit in the current cycle is adjusted according to the shut-off voltage peak value of the previous cycle;

[0018] The shutdown moment of the low-voltage and high-current controllable unit in the next cycle is adjusted according to the shutdown voltage peak value of the current cycle, so that the shutdown voltage of the low-voltage and high-current controllable unit always fluctuates within the preset voltage peak reference interval in all cycles.

[0019] Preferably, the method of adjusting the shutdown moment of the low-voltage and high-current controllable unit in the next cycle according to the shutdown voltage peak value of the current cycle so that the shutdown voltage of the low-voltage and high-current controllable unit is always maintained before the preset voltage peak value fluctuates in the reference interval range in all cycles, further includes:

[0020] The low-voltage and high-current controllable unit and the main current-passing unit are turned on at the same time.

[0021] Preferably, after the low-voltage high-current controllable unit and the main current-passing unit are turned on simultaneously, the method further includes:

[0022] When the conduction time of the low-voltage and high-current controllable unit is greater than the preset conduction time threshold of the low-voltage and high-current controllable unit, the low-voltage and high-current control unit is controlled to actively shut down the current of the main branch where the low-voltage and high-current controllable unit is located, so that the current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the branch where the main branch is located is established.

[0023] Preferably, after adjusting the shutdown moment of the low-voltage and high-current controllable unit in the next cycle according to the shutdown voltage peak value of the current cycle so that the shutdown voltage of the low-voltage and high-current controllable unit always fluctuates within the preset voltage peak reference interval in all cycles, it also includes:

[0024] According to the turn-off voltage peak value of the current cycle of the low-voltage, high-current controllable unit, the turn-off voltage peak value of the next cycle is fine-tuned.

[0025] In a third aspect, the present invention application further proposes an electronic device, comprising: at least one processor and a memory; the memory and the processor are connected via a bus;

[0026] The memory is used to store one or more programs;

[0027] When the one or more programs are executed by the at least one processor, the voltage dynamic regulation method of the converter valve with fine-tuning of the closing time is implemented.

[0028] In a fourth aspect, the present invention application further proposes a readable storage medium having an execution program stored thereon, and when the execution program is executed, the voltage dynamic regulation method of a converter valve with fine-tuning of the closing time is implemented.

[0029] Compared with the closest prior art, the beneficial effects of the present invention are as follows: a converter valve with fine-tuning of the shut-off time of the present invention, the converter valve comprises three groups of parallel branches, each group of branches comprises two groups of bridge arms in series, the bridge arms comprise a main branch; the main branch comprises a low-voltage, high-current controllable unit; the low-voltage, high-current controllable unit is used to adjust the shut-off moment of the low-voltage, high-current controllable unit of the current cycle according to the shut-off voltage peak value of the previous cycle during steady-state operation of the current cycle; the shut-off moment of the low-voltage, high-current controllable unit of the next cycle is adjusted according to the shut-off voltage peak value of the current cycle, so that the shut-off voltage of the low-voltage, high-current controllable unit always fluctuates within the preset voltage peak reference interval range in all cycles. The method of the present invention is adopted to ensure that the shut-off voltage always fluctuates within the preset voltage peak reference interval range in all cycles, so that the shut-off voltage of the converter valve in steady-state operation is maintained at the set interval level. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A structural diagram of a converter valve with fine-tuning closing time provided by the present invention;

[0031] Figure 2 A structural diagram of a low-voltage, high-current controllable unit Vn2 of a converter valve with fine-tuning of the shut-off time provided in the present invention;

[0032] Figure 3 A flowchart of a method for dynamically adjusting voltage of a converter valve with fine-tuning of the shut-off time provided by the present invention;

[0033] Figure 4 A schematic diagram of the off time and terminal voltage of a low-voltage, high-current controllable unit Vn2 of a converter valve with fine-tuning off time provided by the present invention;

[0034] Figure 5 A flowchart of a specific use case of a method for dynamically adjusting voltage of a converter valve with fine-tuning of the closing time provided by the present invention;

[0035] Figure 6 A schematic diagram of the operation of an electronic device provided in the present invention application. DETAILED DESCRIPTION

[0036] The specific implementation methods of the present invention are further described in detail below with reference to the accompanying drawings.

[0037] Embodiment 1:

[0038] like Figure 1 As shown, the present invention proposes a converter valve with fine-tuning of the shut-off time, wherein the converter valve comprises three sets of parallel branches, each set of branches comprises two sets of bridge arms connected in series, and the bridge arms comprise a main branch; the main branch comprises a low-voltage and high-current controllable unit Vn2;

[0039] The low-voltage, high-current controllable unit Vn2 is used to adjust the shutdown moment of the low-voltage, high-current controllable unit Vn2 in the current cycle according to the shutdown voltage peak of the previous cycle during steady-state operation of the current cycle; and to adjust the shutdown moment of the low-voltage, high-current controllable unit Vn2 in the next cycle according to the shutdown voltage peak of the current cycle, so that the shutdown voltage of the low-voltage, high-current controllable unit Vn2 always fluctuates within the preset voltage peak reference interval in all cycles.

[0040] In some implementations, the converter valve expands each bridge arm into a parallel structure of a main branch and an auxiliary branch. In Vnm, n is an integer from 1 to 6, representing a bridge arm; m is an integer from 1 to 3, 1 represents the main flow unit in the bridge arm, 2 represents the low-voltage and high-current controllable unit in the bridge arm, and 3 represents the high-voltage and low-current controllable unit. For example, V12 represents the low-voltage and high-current controllable unit of bridge arm 1. The main branch is composed of a main current-carrying unit Vn1 and a low-voltage, high-current controllable unit Vn2 connected in series. The circuit structure of the main current-carrying unit Vn1 is consistent with the series thyristor valve used in conventional LCC converters. The low-voltage, high-current controllable unit Vn2 is used to shut down the main branch and transfer the current to the corresponding auxiliary branch. The auxiliary branch has large current shutoff capability and reverse voltage tolerance. When the AC system fails and the bridge arm current cannot naturally pass zero, the core component of the high-voltage, low-current controllable unit Vn3 in the auxiliary branch is a fully controlled device, not limited to IGBT (Insulate Gate Bipolar Transistor), IGCT (Integrated Gate Commutated Thyristor), GTO (Gate Turn-off Thyristor), etc. The auxiliary branch can force the current to be transferred to other bridge arms by active shutdown to achieve forced commutation and avoid commutation failure. The low-voltage, high-current controllable unit Vn2 is not limited to Figure 2 The topology form in the circuit is a fully controlled device with the core component capable of actively shutting off large currents and establishing terminal voltages.

[0041] The low voltage and high current controllable unit Vn2 is specifically used for:

[0042] If the turn-off voltage peak value of the previous cycle is higher than the upper limit of the preset voltage peak reference interval, in the current cycle, based on the turn-off time of the previous cycle, the turn-off time of the low-voltage and high-current controllable unit Vn2 of the current cycle is delayed and adjusted;

[0043] If the shutdown voltage of the current cycle is lower than the lower limit of the preset voltage peak reference interval, the shutdown time of the low-voltage and high-current controllable unit Vn2 in the next cycle is adjusted in advance based on the shutdown time of the current cycle.

[0044] In the above, the bridge arm further includes an auxiliary branch connected in parallel with the main branch, and the auxiliary branch includes a high-voltage and low-current controllable unit Vn3; the high-voltage and low-current controllable unit Vn3 is used to actively shut down the current of the auxiliary branch;

[0045] The main branch also includes a main current-passing unit Vn1 connected in series with the low-voltage, high-current controllable unit Vn2;

[0046] The low voltage and high current controllable unit Vn2 is also used to actively shut down the current of the main branch where the low voltage and high current controllable unit Vn2 is located, so that the current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the branch where the main branch is located is established.

[0047] The current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the low-voltage, high-current controllable unit Vn2 increases, that is, the voltage of the branch where the main branch is located is established.

[0048] like Figure 2 As shown, the low-voltage and high-current controllable unit Vn2 is a first topology structure or a second topology structure;

[0049] The first topological structure includes a lightning arrester 1, a first capacitor 2, a first fully-controlled device 3, a fixed resistor 4 and a first diode 5, wherein the lightning arrester 1 is connected in parallel with the first capacitor 2 and the first fully-controlled device 3, the first capacitor 2 is connected in series with the fixed resistor 4, and the fixed resistor 4 is connected in parallel with the first diode 5;

[0050] The second topological structure includes a second fully-controlled device 6, a third fully-controlled device 7, a second diode 8, a third diode 9 and a second capacitor 10. The second fully-controlled device 6 is connected in parallel to the third fully-controlled device 7. The second fully-controlled device 6 is connected in series to the second diode 8. The third fully-controlled device 7 is connected in series to the third diode 9. The node connected between the cathode of the second diode 8 and the anode of the second fully-controlled device 6 and the node connected between the anode of the third diode 9 and the cathode of the third fully-controlled device 7 are connected to the second capacitor 10.

[0051] Embodiment 2:

[0052] The present invention proposes a method for dynamically adjusting the voltage of a converter valve by fine-tuning the closing time, the method comprising the following steps:

[0053] Step 1: When the low-voltage and high-current controllable unit Vn2 in the converter valve for fine-tuning the off-time is in steady-state operation in the current cycle, the off-time of the low-voltage and high-current controllable unit Vn2 in the current cycle is adjusted according to the off-voltage peak value of the previous cycle;

[0054] Step 2: Adjust the shutdown moment of the low voltage and high current controllable unit Vn2 in the next cycle according to the shutdown voltage peak value of the current cycle, so that the shutdown voltage of the low voltage and high current controllable unit Vn2 always fluctuates within the preset voltage peak reference interval in all cycles.

[0055] For example, in step 2: before adjusting the turn-off moment of the low-voltage, high-current controllable unit Vn2 in the next cycle according to the turn-off voltage peak value of the current cycle, so that the turn-off voltage of the low-voltage, high-current controllable unit Vn2 is always maintained within the preset voltage peak reference interval range in all cycles, it may also include:

[0056] The low-voltage, high-current controllable unit Vn2 and the main current-passing unit Vn1 are turned on at the same time.

[0057] The shutdown time of the low voltage and high current controllable unit Vn2 can be adjusted to achieve the purpose of dynamically adjusting the shutdown voltage of the low voltage and high current controllable unit Vn2. The shutdown time of the low voltage and high current controllable unit Vn2 can be adjusted as follows:

[0058] If the turn-off voltage peak value of the previous cycle is higher than the upper limit of the preset voltage peak reference interval, the turn-off time of the low-voltage and high-current controllable unit Vn2 of the previous cycle is adjusted to be delayed for a certain time based on the turn-off time of the previous cycle in the current cycle;

[0059] If the shutdown voltage of the current cycle is lower than the lower limit of the preset voltage peak reference interval, the shutdown time of the low-voltage and high-current controllable unit Vn2 of the next cycle is adjusted to be advanced by a certain time based on the shutdown time of the current cycle.

[0060] In the above, after the low-voltage high-current controllable unit Vn2 and the main current-passing unit Vn1 are turned on at the same time, the following may also be included:

[0061] When the on-time of the low-voltage, high-current controllable unit Vn2 is greater than the preset on-time threshold of the low-voltage, high-current controllable unit Vn2, the low-voltage, high-current control unit is controlled to actively shut down the current of the main branch where the low-voltage, high-current controllable unit Vn2 is located, so that the current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the branch where the main branch is located is established.

[0062] The low-voltage and high-current control unit Vn2 is actively shut down, and the current is transferred from the main branch where the low-voltage and high-current controllable unit Vn2 is located to the corresponding auxiliary branch. The voltage of the low-voltage and high-current controllable unit increases, thereby establishing the voltage of the branch of the main branch where the low-voltage and high-current controllable unit is located.

[0063] In the above, after the off-voltage of the low-voltage and high-current controllable unit Vn2 is kept fluctuating within the preset voltage peak reference interval in all cycles, the method may further include:

[0064] According to the turn-off voltage peak value of the current cycle of the low-voltage, high-current controllable unit Vn2, the turn-off voltage peak value of the next cycle is fine-tuned.

[0065] A voltage dynamic regulation method is proposed for the low-voltage and high-current controllable unit Vn2 of the main branch of the controllable phase-changing converter valve. By comparing the shutdown voltage peak of the low-voltage and high-current controllable unit Vn2 with the preset voltage peak reference interval, the shutdown moment of the low-voltage and high-current controllable unit is directly adjusted without the help of other electrical parameter comparisons. This simplifies the execution process of the converter valve, reduces the delay caused by the multi-step action process of the converter valve, and improves the probability of the converter valve resisting phase-changing failure in the first cycle.

[0066] Embodiment 3:

[0067] like Figure 3 As shown, the present invention application proposes a specific use case of a voltage dynamic regulation method of a converter valve with fine-tuning of the shut-off time, including the following steps:

[0068] Step 1: Based on the low-voltage and high-current controllable unit Vn2 in the converter valve with fine-tuning of the shut-off time, when the converter valve is in steady-state operation in the current cycle, the low-voltage and high-current controllable unit Vn2 adjusts the shut-off time of the next cycle according to the shut-off voltage peak value of the low-voltage and high-current controllable unit Vn2 in the current cycle;

[0069] Step 2: When the shutdown voltage peak is higher than the upper limit of the voltage peak reference interval, the low-voltage and high-current controllable unit Vn2 is shut down for a certain period of time in the next cycle; when the shutdown voltage is lower than the lower limit of the voltage peak reference interval, the low-voltage and high-current controllable unit Vn2 is shut down for a certain period of time in the next cycle.

[0070] In step 1: when the low-voltage high-current controllable unit Vn2 and the main current-passing unit Vn1 are turned on at the same time, the turn-off moment of the low-voltage high-current controllable unit Vn2 can be adjusted to achieve the purpose of dynamically adjusting the turn-off voltage of Vn2.

[0071] When the low-voltage, high-current controllable unit Vn2 and the main current-carrying unit Vn1 are turned on at the same time, the conduction time of the low-voltage, high-current controllable unit Vn2 is greater than the preset conduction threshold, the low-voltage, high-current controllable unit Vn2 is actively turned off, and the current is transferred from the main branch where the low-voltage, high-current controllable unit Vn2 is located to the corresponding auxiliary branch, and the voltage of the low-voltage, high-current controllable unit Vn2 increases.

[0072] The method of the present invention further comprises:

[0073] When the turn-off voltage peak value of the low-voltage and high-current controllable single Vn2 in the previous cycle is lower than the voltage peak reference interval, the turn-off moment of the low-voltage and high-current controllable single Vn2 will be reduced in the next cycle;

[0074] When the turn-off voltage peak value of the low-voltage, high-current controllable single Vn2 in the previous cycle is higher than the voltage peak reference interval, the turn-off moment of the low-voltage, high-current controllable single Vn2 will be increased in the next cycle.

[0075] like Figure 4As shown, the low voltage and high current controllable unit Vn2 and the main current-passing unit Vn1 are turned on at the same time. In order to dynamically adjust the turn-off voltage of the low voltage and high current controllable unit Vn2, the turn-off time of the low voltage and high current controllable unit Vn2 can be adjusted. conn2 , set the reference value of the turn-off time of the low-voltage and high-current controllable unit Vn2 to T offn2 , the initial value is T offn2_low , when T conn2 ≥T offn2 When , the low-voltage and high-current controllable unit Vn2 is actively turned off, the current is transferred from the main branch to the corresponding auxiliary branch, and the low-voltage and high-current controllable unit Vn2 establishes a voltage.

[0076] like Figure 5 , low voltage and high current controllable unit Vn2 Figure 5 Insulated Gate Bipolar Transistor (IGBT) is used to represent the low voltage and high current controllable unit Vn2. Vn2 Within a reasonable range, the reference value T for the shutdown time offn2 A certain degree of adjustment is performed, allowing the reference value T of the shutdown time to be adjusted according to the shutdown voltage peak value of the low-voltage and high-current controllable unit Vn2 in the previous cycle offn2 Make fine adjustments as follows:

[0077] (1) Monitor the turn-off voltage U of the low-voltage, high-current controllable unit Vn2 every cycle Vn2 , and the turn-off voltage peak value of the low-voltage and high-current controllable unit Vn2 is compared with the voltage peak reference interval [U Vn2_low , U Vn2_high ], and according to the comparison result, the shut-off time T off12 Make fine adjustments;

[0078] (2)When U Vn2 Lower than the voltage peak reference interval lower limit U Vn2_low , the next cycle will turn off the low voltage and high current controllable unit Vn2 at the time T offn2 Decrease, the adjustment step is ΔT offn2_DEL (in μs), until the voltage U Vn2 Falling into the voltage peak reference interval [U Vn2_low , U Vn2_high ];

[0079] (3)When U Vn2 Higher than the upper limit U of the voltage peak reference range Vn2_high , the next cycle will turn off the low voltage and high current controllable unit Vn2 at the time T offn2 Increase, the increase adjustment step is ΔT offn2_INL(in μs), until the voltage U Vn2 Falling into the voltage peak reference interval [U Vn2_low , U Vn2_high ].

[0080] Therefore, the reference value T of the turn-off time of the low-voltage and high-current controllable unit Vn2 is offn2 In [T offn2_low , T offn2_high ] interval.

[0081] Based on the existing controllable phase-changing converter valve operation sequence that can resist phase-changing failure, the present invention proposes an improved method for dynamically adjusting the shutdown voltage of the low-voltage and high-current controllable unit of the main branch. When the converter valve is in steady-state operation, the converter valve directly adjusts the shutdown time of the next cycle according to the shutdown voltage peak of the low-voltage and high-current controllable unit of the main branch. When the shutdown voltage peak is higher than the upper limit of the voltage peak reference interval, the low-voltage and high-current controllable unit is shut down for a certain time in the next cycle. When the shutdown voltage is lower than the lower limit of the voltage peak reference interval, the low-voltage and high-current controllable unit is shut down for a certain time in advance in the next cycle. After adopting the shutdown voltage dynamic adjustment method, it can be ensured that the shutdown voltage of the low-voltage and high-current controllable unit of the main branch meets the operation requirements in steady state, thereby improving the reliability of the controllable phase-changing converter valve; the valve control only needs to monitor the voltage peak of the low-voltage and high-current controllable unit, and does not need to monitor and collect other electrical parameters, so it can quickly and accurately realize the shutdown of the low-voltage and high-current controllable unit, shortening the delay caused by the converter valve monitoring multiple electrical parameters.

[0082] Embodiment 4:

[0083] like Figure 6 As shown, the present invention also provides an electronic device, which may be a computer device, a single-chip device, an intelligent mobile device, etc. The electronic device in this embodiment may include a processor, a memory, a transceiver component, etc. The memory, the processor, and the transceiver component are connected via a bus; the memory may be used to store an execution program, and an exemplary execution program may include instructions; the processor is used to execute the instructions stored in the memory. The memory may also be used to store data, which may be called and / or modified when the instructions are executed.

[0084] The processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is specifically suitable for loading and executing one or more instructions in a storage medium to implement a corresponding method flow or a corresponding function, so as to implement the steps of a voltage dynamic regulation method for a converter valve with fine-tuning of the closing time in the above-mentioned embodiment.

[0085] Embodiment 5:

[0086] Based on the same inventive concept, the present invention also provides a readable storage medium, specifically an electronic device readable storage medium (Memory), which is a memory device in the electronic device for storing programs and data. It can be understood that the storage medium here can include both the built-in storage medium in the electronic device and the extended storage medium supported by the electronic device. The storage medium provides a storage space, which stores the operating system of the terminal. In addition, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, and these instructions can be one or more execution programs (including program codes). It should be noted that the storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. The processor loads and executes one or more instructions stored in the storage medium, which can implement the steps of a voltage dynamic adjustment method of a converter valve with fine-tuning of the closing time in the above embodiment.

[0087] Those skilled in the art will appreciate that the embodiments of the present invention application can be provided as methods, systems, or computer program products. Therefore, the present invention application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present invention application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0088] The present invention application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present invention application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0089] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0090] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention application rather than to limit its protection scope. Although the present invention application is described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the present invention application, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the application, but these changes, modifications or equivalent substitutions are all within the protection scope of the claims to be approved.

Claims

1. A converter valve with fine-tuning closing time, the converter valve comprising three sets of parallel branches, each set of branches comprising two sets of bridge arms connected in series, characterized in that: The bridge arm includes a main branch; the main branch includes a low-voltage, high-current controllable unit; The low-voltage, high-current controllable unit is used to adjust the shutdown moment of the low-voltage, high-current controllable unit in the current cycle according to the shutdown voltage peak of the previous cycle during steady-state operation of the current cycle; and adjust the shutdown moment of the low-voltage, high-current controllable unit in the next cycle according to the shutdown voltage peak of the current cycle, so that the shutdown voltage of the low-voltage, high-current controllable unit always fluctuates within a preset voltage peak reference interval in all cycles.

2. The flow control valve according to claim 1, characterized in that: The low voltage and high current controllable unit is specifically used for: If the turn-off voltage peak value of the previous cycle is higher than the upper limit of the preset voltage peak reference interval, in the current cycle, based on the turn-off time of the previous cycle, the turn-off time of the low-voltage and high-current controllable unit of the current cycle is delayed and adjusted; If the shutdown voltage of the current cycle is lower than the lower limit of the preset voltage peak reference interval, the shutdown moment of the low-voltage and high-current controllable unit in the next cycle is adjusted in advance based on the shutdown moment of the current cycle.

3. The flow control valve according to claim 1, characterized in that: The bridge arm further includes an auxiliary branch connected in parallel with the main branch, wherein the auxiliary branch includes a high-voltage and low-current controllable unit; the high-voltage and low-current controllable unit is used to actively shut down the current of the auxiliary branch; The main branch also includes a main flow unit connected in series with the low-voltage and high-current controllable unit; The low-voltage, high-current controllable unit is also used to actively shut down the current of the main branch where the low-voltage, high-current controllable unit is located, so that the current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the branch where the main branch is located is established.

4. The flow control valve according to claim 1, characterized in that: The low-voltage, high-current controllable unit is a first topology structure or a second topology structure; The first topological structure includes a lightning arrester, a first capacitor, a first fully-controlled device, a fixed resistor and a first diode, the lightning arrester is connected in parallel with the first capacitor and the first fully-controlled device, the first capacitor is connected in series with the fixed resistor, and the fixed resistor is connected in parallel with the first diode; The second topological structure includes a second fully-controlled device, a third fully-controlled device, a second diode, a third diode and a second capacitor. The second fully-controlled device is connected in parallel to the third fully-controlled device, the second fully-controlled device is connected in series to the second diode, the third fully-controlled device is connected in series to the third diode, and the node connected between the cathode of the second diode and the anode of the second fully-controlled device and the node connected between the anode of the third diode and the cathode of the third fully-controlled device are connected to the second capacitor.

5. A method for dynamically adjusting the voltage of a converter valve with fine-tuning the closing time, characterized in that: The method comprises: When the low-voltage and high-current controllable unit in the converter valve for controlling the fine-tuning of the shut-off time is in steady-state operation in the current cycle, the shut-off moment of the low-voltage and high-current controllable unit in the current cycle is adjusted according to the shut-off voltage peak value of the previous cycle; The shutdown moment of the low-voltage and high-current controllable unit in the next cycle is adjusted according to the shutdown voltage peak value of the current cycle, so that the shutdown voltage of the low-voltage and high-current controllable unit always fluctuates within the preset voltage peak reference interval in all cycles.

6. The method according to claim 5, characterized in that: The step of adjusting the shutdown moment of the low-voltage and high-current controllable unit in the next cycle according to the shutdown voltage peak value of the current cycle so that the shutdown voltage of the low-voltage and high-current controllable unit is always maintained before the fluctuation of the preset voltage peak reference interval in all cycles further includes: The low-voltage and high-current controllable unit and the main current-passing unit are turned on at the same time.

7. The method according to claim 6, characterized in that: After the low-voltage high-current controllable unit and the main current-passing unit are turned on at the same time, the method further includes: When the conduction time of the low-voltage and high-current controllable unit is greater than the preset conduction time threshold of the low-voltage and high-current controllable unit, the low-voltage and high-current control unit is controlled to actively shut down the current of the main branch where the low-voltage and high-current controllable unit is located, so that the current is transferred from the main branch to the corresponding auxiliary branch, and the voltage of the branch where the main branch is located is established.

8. The method according to claim 5, characterized in that: After adjusting the shutdown moment of the low-voltage and high-current controllable unit in the next cycle according to the shutdown voltage peak value of the current cycle, so that the shutdown voltage of the low-voltage and high-current controllable unit always fluctuates within the preset voltage peak reference interval in all cycles, it also includes: According to the turn-off voltage peak value of the current cycle of the low-voltage, high-current controllable unit, the turn-off voltage peak value of the next cycle is fine-tuned.

9. An electronic device, characterized in that: include: at least one processor and memory; The memory and the processor are connected via a bus; The memory is used to store one or more programs; When the one or more programs are executed by the at least one processor, a voltage dynamic regulation method for a converter valve with fine-tuning of the closing time as claimed in any one of claims 5 to 8 is implemented.

10. A readable storage medium, characterized in that: An execution program is stored thereon, and when the execution program is executed, a voltage dynamic regulation method for a converter valve with fine-tuning of the closing time as described in any one of claims 5 to 8 is implemented.

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