A method for controlling transient overload test of a soft straight valve section and related device

Abstract

The present application belongs to the field of flexible straight valve section test, and discloses a kind of transient overload test control method and related device of flexible straight valve section, to fix the reference wave of test side and the reference wave of test side in preset period calculation, combined with reference voltage calculation real-time input half-bridge flexible straight module number, and send input or cut-off command to half-bridge flexible straight module to maintain normal operation of valve section;During the rated operation of valve section, automatically adjust the AC phase of test side and reference voltage, execute test in four stages: the first stage reduces phase to the first target phase and lifts voltage to the first target voltage to realize voltage lifting, the second stage keeps voltage unchanged and lifts phase to the second target phase to realize current lifting and maintains test target, the third stage restores phase to the first target phase while reducing voltage to rated value to restore voltage level, and the fourth stage restores phase to rated phase to return to rated state.Using this method, the safety and stability of the test process are significantly improved.

Description

Technical Field

[0001] This invention belongs to the technical field of flexible-straight valve sections, specifically relating to the field of transient overload testing of flexible-straight valve sections, and particularly to a transient overload testing control method and related device for flexible-straight valve sections. Background Technology

[0002] With the global trend towards a clean and low-carbon energy structure, wind energy, as a renewable energy source, is experiencing continuous expansion in its development and utilization. As near-shore wind energy resources are gradually depleted, the construction of offshore wind farms is increasingly becoming an important direction for wind energy utilization. Offshore wind farms possess richer and more stable wind resources, but due to their remote geographical location, they rely on efficient and reliable transmission systems to deliver electricity to inland load centers. Flexible DC transmission (VSC-HVDC) systems, with their flexible control and excellent power regulation performance, have become a core technological means to solve the problems of grid connection and long-distance transmission of power from offshore wind farms, effectively alleviating the contradiction between uneven energy distribution and load demand. As a core component of the flexible DC transmission system, the performance of the converter valve directly determines the safe and stable operation of the entire transmission system. Therefore, during the design and mass production stages of converter valve products, it is necessary to verify their performance through valve section-level operational type tests or routine tests. Transient overload tests are one of the key test items, used to assess the short-term operating capability of the flexible DC half-bridge module under conditions exceeding the rated voltage and current.

[0003] In existing transient overload testing techniques for flexible DC converter valves, the test system typically uses a fixed AC phase and reference voltage parameters throughout the entire test. This approach has significant limitations in practical applications: during the voltage rise transition after the test begins and the voltage drop transition before the test ends, the converter valve section is highly susceptible to sudden load changes exceeding its safe operating range. Due to the mismatch between circuit parameters and fixed control parameters during voltage changes, abnormal voltage and current stresses are generated within the valve section, leading to overvoltage, overcurrent, and other faults. This not only affects the smooth conduct of the test but may also cause irreversible damage to the valve section equipment, increasing test costs and the risk of equipment loss.

[0004] It is evident that the existing transient overload test technology for flexible DC converter valves, due to its use of fixed AC phase and reference voltage control, makes the valve section prone to failure during voltage transition. Summary of the Invention

[0005] This invention provides a transient overload test control method and related device for flexible DC converter valve sections, in order to solve the problem that the existing transient overload test technology for flexible DC converter valves, which uses a fixed AC phase and reference voltage control method, is prone to valve section failure during voltage transition.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A transient overload test control method, applied to a test circuit of a flexible direct current valve section, characterized in that it includes:

[0008] The reference waves of the test subject and the testee in the transient overload test are calculated with a fixed preset period.

[0009] By combining the reference wave and reference voltage of the test side and the test side, the number of real-time connected half-bridge flexible DC modules in the valve section on the test side and the test side is calculated.

[0010] Based on the real-time number of half-bridge flexible DC modules engaged on the test side and the test side, commands to engage or disengage the corresponding half-bridge flexible DC modules are sent to achieve normal operation of the valve section.

[0011] When the valve section is in rated operating condition, a transient overload test execution command is issued to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side; wherein, the transient overload test is executed sequentially in four preset stages:

[0012] The first stage involves reducing the AC phase to the first target phase and raising the reference voltage to the first target voltage to achieve voltage boosting.

[0013] Second stage: Maintain the reference voltage as the first target voltage, raise the AC phase to the second target phase to achieve current increase, maintain the operation of this stage to achieve the transient overload test target; wherein, the second target phase is greater than the first target phase;

[0014] The third stage: restore the AC phase to the first target phase, and at the same time reduce the reference voltage to the rated reference voltage to restore the rated operating voltage;

[0015] Fourth stage: Restore the AC phase to the rated phase so that the valve section operating state returns to the rated operating state.

[0016] Furthermore, the specific calculation formula for the reference wave of the test subject and the assistant test subject in the transient overload test, calculated at a fixed preset period, is as follows:

[0017] Module=DC+AC×sin(count×PI / 100+PH×PI / 1800);

[0018] In the formula, Module represents the reference wave; DC is the DC component; AC is the AC amplitude; count is the timer; PI is pi; and PH is the AC phase.

[0019] Furthermore, by combining the reference waveforms and reference voltages of the test side and the test side, the number of real-time engaged half-bridge flexible DC modules in the valve section on both the test side and the test side is calculated. The specific calculation formula is as follows:

[0020] NUM = Module / VOL;

[0021] In the formula, NUM represents the number of half-bridge flexible DC modules that are put into operation in real time; Module represents the reference waveform; and VOL is the reference voltage.

[0022] Furthermore, when the valve section is in rated operating condition, a transient overload test execution command is issued to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side. In rated operating condition, the AC phase on the tested side is 25 degrees and the reference voltage is 2200V.

[0023] Furthermore, in the first stage, the AC phase is reduced to 15 degrees and the reference voltage is raised to 3000V to achieve voltage boosting;

[0024] In the second stage, the reference voltage is maintained at 3000V, and the AC phase is raised to 30 degrees to achieve current increase. This stage is maintained to achieve the transient overload test objective.

[0025] In the third stage, the AC phase is restored to 15 degrees, and the reference voltage is reduced to 2200V to restore the rated operating voltage.

[0026] In the fourth stage, the AC phase is restored to 25 degrees so that the valve section operating state returns to the rated operating state.

[0027] Furthermore, the first target phase, the first target voltage, and the second target phase are all calculated and determined based on the parameters of the flexible DC valve section; the duration of each stage is set based on the actual valve section conditions.

[0028] Furthermore, the flexible DC valve section test circuit includes an adjustable DC power supply, a test valve section, a test valve section, and a load inductor connected in series; wherein: both the test valve section and the test valve section include multiple series-connected half-bridge flexible DC modules; each half-bridge flexible DC module is connected in series and then connected to the DC power supply as a whole; in the transient overload test, the DC power supply replenishes the electrical energy lost by the system.

[0029] A transient overload test control system for a flexible-straight valve section, applied to the test circuit of the flexible-straight valve section, includes:

[0030] The first calculation module is used to calculate the reference wave of the test subject and the testee in the transient overload test at a fixed preset period.

[0031] The second calculation module is used to calculate the number of real-time input half-bridge flexible DC modules in the valve section by combining the reference wave and reference voltage of the test side and the test side.

[0032] The deployment / disconnection command module is used to send deployment or disconnection commands to the corresponding half-bridge flexible DC modules based on the real-time deployment number of half-bridge flexible DC modules on the test side and the test side, so as to achieve normal operation of the valve section.

[0033] The test execution module is used to issue a transient overload test execution command when the valve section is in rated operating condition, so as to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side; wherein, the transient overload test is executed sequentially in four preset stages:

[0034] The first stage involves reducing the AC phase to the first target phase and raising the reference voltage to the first target voltage to achieve voltage boosting.

[0035] Second stage: Maintain the reference voltage as the first target voltage, raise the AC phase to the second target phase to achieve current increase, maintain the operation of this stage to achieve the transient overload test target; wherein, the second target phase is greater than the first target phase;

[0036] The third stage: restore the AC phase to the first target phase, and at the same time reduce the reference voltage to the rated reference voltage to restore the rated operating voltage;

[0037] Fourth stage: Restore the AC phase to the rated phase so that the valve section operating state returns to the rated operating state.

[0038] A transient overload test control device for a flexible direct current valve section includes:

[0039] Memory, used to store computer programs;

[0040] A processor is used to execute the computer program to implement the steps of the transient overload test control method for the flexible direct current valve section described above.

[0041] A computer-readable storage medium storing a computer program, which, when executed by a processor, is used to implement the steps of the transient overload test control method for the above-described flexible direct current valve section.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] This invention provides a transient overload test control method for a flexible DC valve section. It calculates the reference waves of the test side and the side under test at a fixed preset period, calculates the number of flexible DC half-bridge modules to be engaged in real time based on the reference voltage, and sends engagement or disengagement commands to the modules to maintain normal valve section operation. During the rated operation of the valve section, the AC phase and reference voltage of the test side are automatically adjusted, and the test is performed in four stages: The first stage lowers the phase to a first target phase and raises the voltage to the first target voltage to achieve voltage rise; the second stage maintains the voltage and raises the phase to a second target phase to achieve current rise and maintain the test target; the third stage restores the phase to the first target phase while lowering the voltage to the rated value to restore the voltage level; the fourth stage restores the phase to the rated phase to return to the rated state. This method achieves a smooth transition during voltage rise and fall by dynamically adjusting the phase and voltage parameters in stages, avoiding circuit parameter mismatch caused by fixed parameters, thereby preventing sudden load changes from exceeding the safe carrying capacity, ensuring that voltage and current changes are synchronized with system requirements, and reducing the generation of abnormal stress. This method effectively eliminates the risk of overpressure and overcurrent failures caused by parameter imbalance during the test transition of the valve section, significantly improves the safety and stability of the test process, reduces the possibility of equipment damage and test costs, and ensures the smooth implementation of the transient overload test of the flexible DC converter valve and the reliability of the equipment. Attached Figure Description

[0044] Figure 1 A schematic diagram of the topology of the half-bridge flexible DC module provided in an embodiment of the present invention;

[0045] Figure 2 A schematic diagram of the topology of the test circuit for the flexible straight valve section provided in an embodiment of the present invention;

[0046] Figure 3 A flowchart of a transient overload test control method for a flexible straight valve section provided in an embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of a transient overload test control system for a flexible straight valve section provided in an embodiment of the present invention. Detailed Implementation

[0048] To further understand the content of this invention, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments are merely illustrative and not limiting of the invention.

[0049] As described in the background section, the prior art continuously uses a fixed AC phase and reference voltage during transient overload tests; during the voltage rise process after the start of the test and the voltage reduction process after the end of the test, the load on the valve section is too large, which can easily lead to overvoltage and overcurrent faults in the valve section.

[0050] To address the aforementioned issues, this embodiment provides a transient overload test control method for a flexible DC valve section. This method dynamically adjusts the AC phase and reference voltage on the tested side: during the transient overload test, the AC phase and reference voltage on the tested side are dynamically adjusted according to the actual operating stage to avoid overvoltage and overcurrent faults in the valve section. This method effectively prevents excessive load on the valve section during the voltage rise process at the start of the test and the voltage reduction process after the test, thus avoiding overvoltage and overcurrent faults.

[0051] like Figure 3 As shown, this embodiment provides a transient overload test control method for a flexible direct current valve section, including:

[0052] The reference waves of the test subject and the testee in the transient overload test are calculated with a fixed preset period.

[0053] By combining the reference wave and reference voltage of the test side and the test side, the number of real-time connected half-bridge flexible DC modules in the valve section on the test side and the test side is calculated.

[0054] Based on the real-time number of half-bridge flexible DC modules engaged on the test side and the test side, commands to engage or disengage the corresponding half-bridge flexible DC modules are sent to achieve normal operation of the valve section.

[0055] When the valve section is in rated operating condition, a transient overload test execution command is issued to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side; wherein, the transient overload test is executed sequentially in four preset stages:

[0056] The first stage involves reducing the AC phase to the first target phase and raising the reference voltage to the first target voltage to achieve voltage boosting.

[0057] Second stage: Maintain the reference voltage as the first target voltage, raise the AC phase to the second target phase to achieve current increase, maintain the operation of this stage to achieve the transient overload test target; wherein, the second target phase is greater than the first target phase;

[0058] The third stage: restore the AC phase to the first target phase, and at the same time reduce the reference voltage to the rated reference voltage to restore the rated operating voltage;

[0059] Fourth stage: Restore the AC phase to the rated phase so that the valve section operating state returns to the rated operating state.

[0060] The comprehensive evaluation method provided in this embodiment will be further explained below:

[0061] like Figure 2As shown, the transient overload test control method for the flexible DC valve section provided in this embodiment is applied to the transient overload test circuit of the flexible DC valve section. The valve section test is a test that uses standard test conditions to test the key components of the converter valve under actual operating conditions. The transient overload test circuit mainly consists of an adjustable DC power supply, a test valve section (valve section 1), a test valve section (valve section 2), and a load inductor. The test valve section (both the test valve section and the test valve section) is composed of n sub-modules (the number of n can be determined according to the test requirements and the maximum voltage of the adjustable DC power supply, generally not exceeding 6) connected in series. After the sub-modules of the test valve section are connected in series, the entire system is connected to the DC power supply, and the DC power supply replenishes the electrical energy lost by the system during the test.

[0062] During the test preparation phase, the output voltage of the DC power supply is gradually increased to charge each submodule in the valve section to its energy extraction voltage. After a preset delay time and confirmation that all modules are functioning normally, the control system unlocks the valve section. Subsequently, the DC power supply voltage is further increased to the specified operating voltage, and the control system simultaneously increases the phase difference of the reference waves on both sides of the valve section, raising the loop current to the specified operating current. After sufficient warm-up time, a transient overload test can be performed.

[0063] Each submodule in the valve section test adopts a half-bridge flexible DC module, the specific structure of which is as follows: Figure 1 As shown, it consists of capacitors, resistors, IGBTs, and diodes. A half-bridge flexible DC module generally has three operating states: First, latched state: neither VT1 nor VT2 is conducting. Second, engaged state: VT1 is conducting, and VT2 is not conducting. Third, disengaged state: VT1 is not conducting, and VT2 is conducting.

[0064] To address the issue of excessive load on the valve section during the voltage rise process at the start of the test and the voltage reduction process after the test, which can easily lead to overvoltage and overcurrent faults, this embodiment provides a transient overload test control method for a flexible direct current valve section. The specific steps are as follows:

[0065] Step 1: The control system calculates the reference waves for the test partner and the test subject at a fixed period (0.1ms for example);

[0066] Step 2: Divide the reference wave by the reference voltage to calculate the number of real-time input modules on the test side and the tested side in the valve section;

[0067] Step 3: Select the power module through the algorithm and send it an activation or deactivation command to complete the normal operation of the valve section.

[0068] The formula for calculating the reference wave is as follows:

[0069] Module=DC+AC*sin(count*PI / 100+PH*PI / 1800)

[0070] The formula for calculating the number of modules to be deployed is as follows (the result is rounded):

[0071] NUM = Module / VOL

[0072] In the formula, DC is the DC component, AC is the AC amplitude, count is the timer (automatically increments by 1 in each control cycle), PI is pi (value 3.1415926 in the program), PH is the AC phase, and VOL is the reference voltage.

[0073] Step 4: Assuming that under rated operating conditions, the AC phase PH of the test side is 25 degrees and the reference voltage VOL is 2200V, a command is issued to start the transient overload test. The AC phase and reference voltage in the reference wave calculation formula of the test side are automatically modified according to the preset parameters. It can be seen that the AC phase and reference voltage of the test side are dynamically adjusted according to the test stage during operation.

[0074] The specific experiment is divided into four stages: In the first stage, the pH is reduced to 15 degrees and the VOL is increased to 3000V to achieve the goal of raising the voltage; during the initial voltage raising process of the test side, the AC phase is automatically reduced to reduce the system load in the early stage.

[0075] In the second stage, the VOL is kept elevated while the pH is kept at 30 degrees to achieve the target of raising the current. At this time, the operation is maintained to achieve the target of transient overload test. After the voltage rises to the target value, the phase is automatically raised so that the valve section current also reaches the target value.

[0076] The third stage involves reducing the pH to 15 degrees and the VOL to 2200V, restoring the rated operating voltage.

[0077] The fourth stage restores the pH to 25 degrees Celsius, at which point the system returns to its rated operating state.

[0078] Finally, after the transient process ends, the AC phase is reduced by lowering the voltage on the tested side to reduce the system load. Once the voltage returns to normal, the normal operating phase is automatically restored.

[0079] It should be noted that the above actual values ​​are hypothetical and should be calculated based on different flexible straight valve section parameters. The duration of each stage should also be set according to the actual valve section conditions.

[0080] like Figure 4As shown, this embodiment also provides a transient overload test control system for a flexible DC valve section, including: a first calculation module, used to calculate the reference waves of the test side and the tested side during the transient overload test at a fixed preset period; a second calculation module, used to calculate the number of real-time engaged half-bridge flexible DC modules on the test side and the tested side of the valve section by combining the reference waves and reference voltage on the test side and the tested side; a switching command module, used to send engagement or disengagement commands to the corresponding half-bridge flexible DC modules based on the number of real-time engaged half-bridge flexible DC modules on the test side and the tested side, so as to realize the normal operation of the valve section; and a test execution module, used to issue a transient overload test execution command when the valve section is in the rated operating state, so as to automatically adjust the reference wave corresponding to the tested side. The AC phase and reference voltage are specified. The transient overload test is performed sequentially in four preset stages: Stage 1: The AC phase is reduced to the first target phase, and the reference voltage is increased to the first target voltage to achieve voltage increase; Stage 2: The reference voltage is maintained at the first target voltage, and the AC phase is increased to the second target phase to achieve current increase. This stage is maintained to achieve the transient overload test objective; wherein the second target phase is greater than the first target phase; Stage 3: The AC phase is restored to the first target phase, and the reference voltage is reduced to the rated reference voltage to restore the rated operating voltage; Stage 4: The AC phase is restored to the rated phase so that the valve section operating state returns to the rated operating state.

[0081] The present invention also provides a transient overload test control device for a flexible-straight valve section, comprising: a memory for storing a computer program; and a processor for executing the computer program to implement the steps of the transient overload test control method for the flexible-straight valve section.

[0082] This invention also provides a computer program product, including a computer program / instructions, which, when executed by a processor, implements the steps of the transient overload test control method for the flexible DC valve section. When the processor executes the computer program, it implements the aforementioned transient overload test control steps for the flexible DC valve section, for example: calculating the reference waves of the test side and the tested side during the transient overload test at a fixed preset period; calculating the real-time number of half-bridge flexible DC modules engaged on the test side and the tested side of the valve section by combining the reference waves and reference voltages of the test side and the tested side; sending engagement or disengagement commands to the corresponding half-bridge flexible DC modules based on the real-time number of engaged half-bridge flexible DC modules on the test side and the tested side to achieve normal operation of the valve section; and issuing a transient overload test execution command when the valve section is in rated operating condition to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side; wherein, the... The transient overload test is performed sequentially in four preset stages: Stage 1: The AC phase is reduced to the first target phase, and the reference voltage is increased to the first target voltage to achieve voltage increase; Stage 2: The reference voltage is maintained at the first target voltage, and the AC phase is increased to the second target phase to achieve current increase. This stage is maintained to achieve the transient overload test objective; wherein, the second target phase is greater than the first target phase; Stage 3: The AC phase is restored to the first target phase, and the reference voltage is reduced to the rated reference voltage to restore the rated operating voltage; Stage 4: The AC phase is restored to the rated phase so that the valve section operating state returns to the rated operating state.

[0083] For example, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of performing preset functions, wherein the instruction segments describe the execution process of the computer program in the transient overload test control device of the flexible-straight valve section. For example, the computer program can be divided into a first calculation module, a second calculation module, a switching command module, and a test execution module; the specific functions of each module are as follows: the first calculation module is used to calculate the reference waves of the test side and the tested side in the transient overload test at a fixed preset period; the second calculation module is used to calculate the number of real-time engaged half-bridge flexible DC modules in the valve section by combining the reference waves and reference voltages of the test side and the tested side; the switching command module is used to send engagement or disengagement commands to the corresponding half-bridge flexible DC modules based on the number of real-time engaged half-bridge flexible DC modules in the test side and the tested side, so as to realize the normal operation of the valve section; the test execution module is used to issue a transient overload test execution command when the valve section is in the rated operating state, so as to automatically The AC phase and reference voltage corresponding to the reference wave on the tested side are adjusted; wherein, the transient overload test is performed sequentially in four preset stages: First stage: the AC phase is reduced to the first target phase, and the reference voltage is increased to the first target voltage to achieve voltage increase; Second stage: the reference voltage is maintained at the first target voltage, and the AC phase is increased to the second target phase to achieve current increase, maintaining the operation of this stage to achieve the transient overload test target; wherein, the second target phase is greater than the first target phase; Third stage: the AC phase is restored to the first target phase, and the reference voltage is reduced to the rated reference voltage to restore the rated operating voltage; Fourth stage: the AC phase is restored to the rated phase so that the valve section operating state returns to the rated operating state.

[0084] The transient overload test control device for the flexible-vertical valve section can be a computing device such as a desktop computer, laptop, handheld computer, or cloud server. The transient overload test control device for the flexible-vertical valve section may include, but is not limited to, a processor and memory. Those skilled in the art will understand that the above are examples of transient overload test control devices for flexible-vertical valve sections and do not constitute a limitation on such devices. The device may include more components than described above, or combine certain components, or use different components. For example, the transient overload test control device for the flexible-vertical valve section may also include input / output devices, network access devices, buses, etc.

[0085] The processor referred to can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor, or any conventional processor, etc. The processor is the control center for the transient overload test control of the flexible DC valve section, connecting various parts of the transient overload test control equipment of the entire flexible DC valve section via various interfaces and lines.

[0086] The memory can be used to store the computer program and / or modules. The processor implements various functions of the transient overload test control device of the flexible direct current valve section by running or executing the computer program and / or modules stored in the memory and calling the data stored in the memory.

[0087] The memory may primarily include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a function (such as sound playback, image playback, etc.). The data storage area may store data created based on the use of the mobile phone (such as audio data, phonebook, etc.). Furthermore, the memory may include high-speed random access memory and non-volatile memory, such as hard disks, RAM, plug-in hard disks, smart media cards (SMC), secure digital cards (SD cards), flash cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.

[0088] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the transient overload test control method for a flexible direct current valve section.

[0089] If the module / unit integrated into the transient overload test control system of the flexible straight valve section is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium.

[0090] Based on this understanding, the present invention can implement all or part of the process in the transient overload test control method for the flexible-vertical valve section, or it can be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of the transient overload test control method for the flexible-vertical valve section. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or preset intermediate form, etc.

[0091] The computer-readable storage medium may include: any entity or device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc.

[0092] The above embodiments are merely one of the implementation methods for achieving the technical solution of the present invention. The scope of protection claimed by the present invention is not limited to this embodiment, but also includes any variations, substitutions and other implementation methods that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A transient overload test control method, applied to a test circuit of a flexible direct current valve section, characterized in that, include: The reference waves of the test subject and the testee in the transient overload test are calculated with a fixed preset period. By combining the reference wave and reference voltage of the test side and the test side, the number of real-time connected half-bridge flexible DC modules in the valve section on the test side and the test side is calculated. Based on the real-time number of half-bridge flexible DC modules engaged on the test side and the test side, commands to engage or disengage the corresponding half-bridge flexible DC modules are sent to achieve normal operation of the valve section. When the valve section is in rated operating condition, a transient overload test execution command is issued to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side; wherein, the transient overload test is executed sequentially in four preset stages: The first stage involves reducing the AC phase to the first target phase and raising the reference voltage to the first target voltage to achieve voltage boosting. Second stage: Maintain the reference voltage as the first target voltage, raise the AC phase to the second target phase to achieve current increase, maintain the operation of this stage to achieve the transient overload test target; wherein, the second target phase is greater than the first target phase; The third stage: restore the AC phase to the first target phase, and at the same time reduce the reference voltage to the rated reference voltage to restore the rated operating voltage; Fourth stage: Restore the AC phase to the rated phase so that the valve section operating state returns to the rated operating state; The reference waves for both the test subject and the assistant test subject in the transient overload test are calculated using a fixed preset period. The specific calculation formula is as follows: Module=DC+AC×sin(count×PI / 100+PH×PI / 1800); In the formula, Module represents the reference wave; DC is the DC component; AC is the AC amplitude; count is the timer; PI is pi; and PH is the AC phase. By combining the reference waveforms and reference voltages of the test side and the test side, the number of real-time activated half-bridge flexible DC modules in the valve section on both the test side and the test side is calculated. The specific calculation formula is as follows: NUM = Module / VOL; In the formula, NUM represents the number of half-bridge flexible DC modules that are activated in real time; Module represents the reference waveform; VOL is the reference voltage; The flexible DC valve section test circuit includes an adjustable DC power supply, a test valve section, a test valve section, and a load inductor connected in series; wherein: both the test valve section and the test valve section include multiple series-connected half-bridge flexible DC modules; each half-bridge flexible DC module is connected in series and then connected to the DC power supply as a whole; in the transient overload test, the DC power supply replenishes the electrical energy lost by the system.

2. The transient overload test control method according to claim 1, characterized in that, When the valve section is in rated operating condition, a transient overload test execution command is issued to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side. In rated operating condition, the AC phase on the tested side is 25 degrees and the reference voltage is 2200V.

3. The transient overload test control method according to claim 1, characterized in that, In the first stage, the AC phase is reduced to 15 degrees and the reference voltage is raised to 3000V to achieve voltage boosting; In the second stage, the reference voltage is maintained at 3000V, and the AC phase is raised to 30 degrees to achieve current increase. This stage is maintained to achieve the transient overload test objective. In the third stage, the AC phase is restored to 15 degrees, and the reference voltage is reduced to 2200V to restore the rated operating voltage. In the fourth stage, the AC phase is restored to 25 degrees so that the valve section operating state returns to the rated operating state.

4. The transient overload test control method according to claim 1, characterized in that, The first target phase, the first target voltage, and the second target phase are all calculated and determined based on the parameters of the flexible direct current valve section; the duration of each stage is set based on the actual valve section conditions.

5. A transient overload test control system for a flexible-straight valve section, applied to the test circuit of the flexible-straight valve section, used to implement the transient overload test control method according to any one of claims 1-4, characterized in that, include: The first calculation module is used to calculate the reference wave of the test subject and the testee in the transient overload test at a fixed preset period. The second calculation module is used to calculate the number of real-time input half-bridge flexible DC modules in the valve section by combining the reference wave and reference voltage of the test side and the test side. The deployment / disconnection command module is used to send deployment or disconnection commands to the corresponding half-bridge flexible DC modules based on the real-time deployment number of half-bridge flexible DC modules on the test side and the test side, so as to achieve normal operation of the valve section. The test execution module is used to issue a transient overload test execution command when the valve section is in rated operating condition, so as to automatically adjust the AC phase and reference voltage corresponding to the reference wave on the tested side; wherein, the transient overload test is executed sequentially in four preset stages: The first stage involves reducing the AC phase to the first target phase and raising the reference voltage to the first target voltage to achieve voltage boosting. Second stage: Maintain the reference voltage as the first target voltage, raise the AC phase to the second target phase to achieve current increase, maintain the operation of this stage to achieve the transient overload test target; wherein, the second target phase is greater than the first target phase; The third stage: restore the AC phase to the first target phase, and at the same time reduce the reference voltage to the rated reference voltage to restore the rated operating voltage; Fourth stage: Restore the AC phase to the rated phase so that the valve section operating state returns to the rated operating state.

6. A transient overload test control device for a flexible direct current valve section, characterized in that, include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the steps of the transient overload test control method according to any one of claims 1-4.

7. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it is used to implement the steps of the transient overload test control method according to any one of claims 1-4.

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