Control method and device for towing test, storage medium and electronic device

Abstract

The application discloses a control method and device for a drag test, a storage medium and an electronic device, and relates to the technical field of drag test control. The method comprises the following steps: closing a loop and a control cabinet; the loop comprises: a direct-current test power supply, a first power low-voltage module and a second power low-voltage module connected with the direct-current test power supply respectively, a first high-frequency transformer connected between the first power low-voltage module and a first power high-voltage module, and a second high-frequency transformer connected between the second power low-voltage module and a second power high-voltage module; the first power high-voltage module and the second power high-voltage module are connected through a load reactance, and an energy storage auxiliary test module is connected between the second power high-voltage module and the second high-frequency transformer; the control cabinet is connected to the first power high-voltage module and the second power high-voltage module through optical fibers respectively, and is used for generating a first switching pulse and a second switching pulse acting on the first power high-voltage module and the second power high-voltage module respectively, so as to control a drag test on the loop.

Description

Technical Field

[0001] This application relates to the field of power electronic transformer testing technology, and more specifically, to a control method and apparatus, storage medium and electronic device for drag testing. Background Technology

[0002] Power electronic transformers are composed of power submodules arranged in different ways according to various needs and scenarios. The power module is the core component of a power electronic transformer, and its design performance directly affects the entire unit. Typical power electronic transformers use a series input and parallel output configuration to reduce voltage levels while meeting power output requirements; its input stage can employ a cascaded H-bridge structure, enabling direct connection to medium-voltage AC systems. Power electronic transformers generally use isolated DC / DC converters to achieve voltage level transformation and electrical isolation. Currently, widely used isolated transformers mainly include dual active bridge rectifier converters and LLC resonant converters. For power modules with the above topologies, parallel connection of the input and output sides can be used to control the phase shift between the H-bridges on the primary and secondary sides of the transformer. Some solutions propose a DC transformer module parallel connection test scheme suitable for voltage equalization circuits + LLC resonant converters; however, current module testing methods are generally only applicable to power module topologies where both the primary and secondary sides of the transformer are H-bridges.

[0003] The above-mentioned solutions cannot be used for power module testing of power electronic transformers with single-phase power transmission in specific scenarios, such as photovoltaic power plants. For example, in the case of a high-voltage direct-connected power electronic transformer power module, its low-voltage side is connected in parallel to the photovoltaic combiner box output. After isolation DC / DC conversion, it is then cascaded through a high-voltage H-bridge and connected to the AC grid, achieving only unidirectional power output. Therefore, the power submodule topology does not need to use fully controlled devices, unlike the other solutions mentioned above. Furthermore, current parallel-drive technologies lack a safe, reliable, simple, and efficient control method for the power control stage. In summary, a technical solution is urgently needed for parallel-drive testing of power submodules with single-phase power output.

[0004] There is a lack of effective control schemes for the drag test of power modules in power electronic transformers for single-phase power transmission in related technologies. Summary of the Invention

[0005] This application provides a control method and apparatus for drag testing, a storage medium, and an electronic device to at least solve the problem in the prior art of lacking a drag testing control scheme for the power module of a power electronic transformer with single-phase power transmission.

[0006] According to one embodiment of this application, a control system for a drag test is provided, comprising: a closed loop and a control chassis; wherein the closed loop includes: a DC test power supply, a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module, and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein the first high-voltage power module and the second high-voltage power module are connected via a load reactor, and an energy storage test module is further connected between the second high-voltage power module and the second high-frequency transformer; wherein the control chassis is connected to the first high-voltage power module and the second high-voltage power module respectively via optical fibers, and is used to generate a first switching pulse and a second switching pulse respectively acting on the first high-voltage power module and the second high-voltage power module, and is also used to control the drag test of the closed loop through the first switching pulse and the second switching pulse.

[0007] In an exemplary embodiment, the control chassis is further configured to generate a first modulation wave of the first high-voltage power module and to generate a first switching pulse through the first modulation wave; the control chassis is further configured to receive a sampled current of the load reactance collected by a current sampling Hall sensor through a sampling interface, wherein the sampling Hall sensor is connected in series with the load reactance; the control chassis is further configured to detect the phase angle of the first modulation wave through a single-phase lock-in loop; and to generate a second switching pulse through the sampled current and the phase angle.

[0008] In one exemplary embodiment, the control chassis is further configured to determine the AC current reference corresponding to the load reactance by means of the phase angle; the control chassis is further configured to generate the second switching pulse by means of the sampled current and the AC current reference.

[0009] In an exemplary embodiment, the control chassis is further connected to the first low-voltage power module, the second low-voltage power module, and the energy storage test module via optical fibers; the control chassis is also used to control the unlocking of the target module, wherein the target module includes: the first low-voltage power module, the first high-voltage power module, the second high-voltage power module, and the energy storage test module.

[0010] In an exemplary embodiment, the control chassis is provided with a touch screen, which is used by the target object to set target information to the control chassis, wherein the target information includes: the modulation index for generating the first switching pulse and the overcurrent protection setting of the load reactance.

[0011] In one exemplary embodiment, the DC test power supply is connected to a three-phase AC power grid via a three-phase bridge converter, wherein the three-phase bridge converter is used to rectify the output of the three-phase AC power grid.

[0012] According to another embodiment of this application, a method for controlling a drag test is also provided, comprising: generating a first switching pulse and a second switching pulse respectively acting on a first high-voltage power module and a second high-voltage power module through a control chassis; controlling a drag test on a closed loop through the first switching pulse and the second switching pulse; wherein the closed loop includes: a DC test power supply, a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module, and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein the first high-voltage power module and the second high-voltage power module are connected through a load reactor, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer; the control chassis is connected to the first high-voltage power module and the second high-voltage power module respectively through optical fibers.

[0013] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer program, and the computer program is configured to execute the above-described method at runtime.

[0014] According to another aspect of the embodiments of this application, an electronic device is also provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the above-described method through the computer program.

[0015] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps in any of the above method embodiments.

[0016] In this embodiment, a closed loop and a control chassis are provided. The closed loop includes: a DC test power supply; a first low-voltage power module and a second low-voltage power module connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module; and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module. The first high-voltage power module and the second high-voltage power module are connected via a load reactance, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer. The control chassis is connected to the first high-voltage power module and the second high-voltage power module via optical fibers, and is used to generate a first switching pulse and a second switching pulse acting on the first high-voltage power module and the second high-voltage power module, respectively. It is also used to control the drag test of the closed loop using the first switching pulse and the second switching pulse. This embodiment solves the problem in the prior art of lacking a drag test control scheme for the power modules of power electronic transformers with single-phase power transmission, and achieves the technical effect of providing a safe, reliable, simple, and efficient drag test scheme for the power modules of power electronic transformers with single-phase power transmission. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0018] Figure 1 This is a hardware structure block diagram of a computer terminal for a method of controlling a drag test according to an embodiment of this application;

[0019] Figure 2 This is a flowchart of a control method for a drag test according to an embodiment of this application;

[0020] Figure 3 This is a schematic diagram of the architecture of the control system for the drag test according to an embodiment of this application;

[0021] Figure 4 This is another schematic diagram of the control system for the drag test according to an embodiment of this application;

[0022] Figure 5 This is a schematic diagram of a power control strategy according to an embodiment of this application;

[0023] Figure 6 This is an architecture diagram of the control system for a drag test according to an embodiment of this application. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0025] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus; "a plurality" means two or more.

[0026] The methods and embodiments provided in this application can be executed on a computer terminal or similar computing device, cloud platform, independent physical server, or software platform, wherein the aforementioned software platform runs through one or more servers. Taking running on a computer terminal as an example, Figure 1 This is a hardware structure block diagram of a computer terminal for a drag test control method according to an embodiment of this application. Figure 1 As shown, a computer terminal may include one or more ( Figure 1 (Only one is shown in the image) A processor 102 and a memory 104 for storing data. In one exemplary embodiment, the computer terminal may further include a transmission device 106 for communication functions and an input / output device 108. The processor 102 may include, but is not limited to, a processing device such as a microprocessor (MCU) or a programmable logic device (FPGA). Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the computer terminal described above. For example, the computer terminal may also include components that are more complex than those described above. Figure 1 The more or fewer components shown, or having the same Figure 1 Equivalent functions or ratios shown Figure 1 The functions shown have more different configurations.

[0027] The memory 104 can be used to store computer programs, such as application software programs and modules, like the computer program corresponding to the method in this embodiment. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, thus implementing the above-described method. The memory 104 may include high-speed random access memory and non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor 102, and these remote memories can be connected to a computer terminal via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0028] The transmission device 106 is used to receive or send data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider for the computer terminal. In one example, the transmission device 106 includes a Network Interface Controller (NIC), which can connect to other network devices via a base station to communicate with the Internet. In another example, the transmission device 106 may be a Radio Frequency (RF) module used for wireless communication with the Internet.

[0029] This embodiment provides a method for controlling dragging tests, which is applied to the aforementioned computer terminal. Figure 2 This is a flowchart of a control method for a drag test according to an embodiment of this application, the process including the following steps:

[0030] Step S202: The control chassis generates a first switching pulse and a second switching pulse that act on the first power high voltage module and the second power high voltage module, respectively.

[0031] Step S204: Control the pull-out test of the closed loop through the first switch pulse and the second switch pulse; wherein, the closed loop includes: a DC test power supply, a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module, and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein, the first high-voltage power module and the second high-voltage power module are connected through a load reactor, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer; the control chassis is connected to the first high-voltage power module and the second high-voltage power module respectively through optical fibers.

[0032] In one exemplary embodiment, the DC test power supply is connected to a three-phase AC power grid via a three-phase bridge converter, wherein the three-phase bridge converter is used to rectify the output of the three-phase AC power grid.

[0033] Generating first and second switching pulses that act on the first and second power high-voltage modules respectively, and controlling the pull-out test of the closed loop through these pulses, is a key step in realizing the performance test of the power module of the power electronic transformer.

[0034] In an exemplary embodiment, the control chassis is further configured to generate a first modulation wave of the first high-voltage power module and to generate a first switching pulse through the first modulation wave; the control chassis is further configured to receive a sampled current of the load reactance collected by a current sampling Hall sensor through a sampling interface, wherein the sampling Hall sensor is connected in series with the load reactance; the control chassis is further configured to detect the phase angle of the first modulation wave through a single-phase lock-in loop; and to generate a second switching pulse through the sampled current and the phase angle.

[0035] In one exemplary embodiment, the control chassis is further configured to determine the AC current reference corresponding to the load reactance by means of the phase angle; the control chassis is further configured to generate the second switching pulse by means of the sampled current and the AC current reference.

[0036] The process is described in detail below:

[0037] Specifically, generating a first switching pulse for the first power high-voltage module includes:

[0038] 1) On the touchscreen of the control chassis, set the modulation index of the first high-voltage power module. The modulation index determines the modulation depth of the H-bridge of the first high-voltage power module, i.e., the efficiency and capability of power conversion. 2) According to the set modulation index, the control chassis generates a corresponding modulation wave signal to control the power output of the H-bridge of the first high-voltage power module. 3) Generate the first switching pulse from the modulation wave using a single-stage frequency multiplication modulation method. This process ensures that the H-bridge switching elements (such as IGBTs) switch according to the predetermined frequency and duty cycle, thereby achieving efficient power conversion.

[0039] Furthermore, the generation of a second switching pulse for the second high-voltage power module includes: 1) Real-time monitoring of the load reactance current using a current sampling Hall sensor, and transmitting the data back to the control chassis. This step provides the necessary real-time feedback signal for the generation of the second switching pulse. 2) The control chassis uses a closed-loop control strategy to generate a modulation wave for the second high-voltage power module based on the real-time current sampling value of the load reactance, the current reference value, and the modulation wave of the first high-voltage power module. This modulation wave is generated by calculating the difference between the actual value and the reference value of the load reactance current, then processing the output of the PI controller for amplitude limiting, and superimposing it with the feedforward amount of the modulation wave of the first high-voltage power module. 3) Similar to the generation method of the first switching pulse, the second switching pulse is also generated through a single-stage frequency doubling modulation method, controlling the switching state of its H-bridge switching elements according to the modulation wave signal of the second high-voltage power module.

[0040] In an exemplary embodiment, the control chassis is further connected to the first low-voltage power module, the second low-voltage power module, and the energy storage test module via optical fibers; the control chassis is also used to control the unlocking of the target module, wherein the target module includes: the first low-voltage power module, the first high-voltage power module, the second high-voltage power module, and the energy storage test module.

[0041] In an exemplary embodiment, the control chassis is provided with a touch screen, which is used by the target object to set target information to the control chassis, wherein the target information includes: the modulation index for generating the first switching pulse and the overcurrent protection setting of the load reactance.

[0042] In other words, the drag test for controlling the closed loop includes:

[0043] 1) Unlock the first low-voltage power module: When the DC power supply is turned on, the first low-voltage power module is unlocked first, so that it can start to receive energy from the DC power supply and convert the energy to the high-voltage side through the first high-frequency transformer.

[0044] 2) Unlock the first high-voltage power module: After the voltage on both sides of the first high-frequency transformer stabilizes, unlock the first high-voltage power module and start outputting power to the load reactor.

[0045] 3) Unlock the second high-voltage power module: When the first high-voltage power module outputs stable power and the capacitor of the second high-voltage power module is charged to a stable voltage, unlock the second high-voltage power module so that it can receive the power transmitted by the first high-voltage power module through the load reactor and convert it to the low-voltage side through the second high-frequency transformer.

[0046] 4) Energy Storage Test Module Intervention: Finally, unlock the energy storage test module to participate in the power cycle. The energy storage test module can not only absorb power from the second high-voltage power module, but also release energy when needed to help maintain the power balance of the test circuit.

[0047] 5) Power Regulation and Monitoring: Power parameters, such as current reference values ​​and PI controller parameters, can be manually set or automatically adjusted via the control chassis's touchscreen to control the load reactance current, thereby regulating the power of the entire circuit. Simultaneously, the control chassis continuously monitors and displays the status and key parameters of each module, ensuring the test is conducted under safe and controllable conditions.

[0048] After the two power modules are unlocked and operating stably, the first and second switching pulses work in coordination, allowing energy to circulate between the first and second high-voltage power modules, forming a closed loop. This ensures the continuity and stability of power during the test, while reducing the need for external high-capacity loads or power supplies.

[0049] Through the above process, a drag test can be performed on the first power high-voltage module and the second power high-voltage module to verify their performance under different operating conditions, without the need for an actual power grid or load, thus forming a closed and self-sufficient test environment.

[0050] Through the above steps, a first switching pulse and a second switching pulse are generated, respectively acting on the first high-voltage power module and the second high-voltage power module. The first and second switching pulses control the pull-out test of the closed loop. The closed loop includes: a DC test power supply; a first low-voltage power module and a second low-voltage power module connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module; and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module. The first high-voltage power module and the second high-voltage power module are connected via a load reactance, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer. The control chassis is connected to the first high-voltage power module and the second high-voltage power module via optical fibers. This embodiment solves the problem in the prior art of lacking a pull-out test control scheme for power modules of power electronic transformers with single-phase power transmission, achieving the technical effect of providing a safe, reliable, simple, and efficient pull-out test scheme for power modules of power electronic transformers with single-phase power transmission.

[0051] To better understand the process of the above-described control method for dragging tests, the following description, in conjunction with optional embodiments, further illustrates the control method for dragging tests, but is not intended to limit the technical solutions of the embodiments of this application.

[0052] To address the problem that existing technical solutions are not applicable to current power module testing, the purpose of this application is to provide a power module testing method and system for power electronic transformers with single-phase power output.

[0053] like Figure 3 The power electronic transformer power module drag test system shown (equivalent to the control system of the drag test described above) includes: a DC test power supply, a first group of high-voltage power modules (equivalent to the first high-voltage power module in the above embodiment), a first group of high-frequency transformers (equivalent to the first high-frequency transformer in the above embodiment), a first group of low-voltage power modules (equivalent to the first low-voltage power module in the above embodiment), a second group of high-voltage power modules (equivalent to the second high-voltage power module in the above embodiment), a second group of high-frequency transformers (equivalent to the second high-frequency transformer in the above embodiment), a second group of low-voltage power modules (equivalent to the second low-voltage power module in the above embodiment), an energy storage auxiliary test power module, a load reactance, a current sampling Hall sensor, and a control chassis.

[0054] The specific connection method of the drag test system is as follows: The DC side of the first group of low-voltage power modules is connected to the DC test power supply, and the AC side is connected to the low-voltage side of the first group of high-frequency transformers; the rectifier bridge port of the first group of high-voltage power modules is connected to the high-voltage side of the first group of high-frequency transformers, and the H-bridge port is connected to the load reactor; the H-bridge port of the second group of high-voltage power modules is connected to the H-bridge port of the first group of high-voltage power modules through the load reactor, and the DC capacitor side is connected to the DC side of the energy storage test power module; the AC bridge port of the energy storage test power module is connected to the high-voltage side of the second group of high-frequency transformers; the AC side of the second group of low-voltage power modules is connected to the low-voltage side of the second group of high-frequency transformers, and the DC side is connected in parallel with the DC side of the first group of low-voltage power modules; the current sampling Hall effect monitors the real-time current data of the load reactor, and the sampling information is uploaded to the control box; the control box is connected to the control boards of the first group of low-voltage power modules, the first group of high-voltage power modules, the second group of high-voltage power modules, and the energy storage test power module through optical fiber, and controls the unlocking of each group of modules and the adjustment of the load reactor power.

[0055] To provide power to the test module group, the DC test power is obtained by rectifying a three-phase AC power grid connected to a three-phase bridge converter; the three-phase bridge converter uses fully controlled power electronic devices.

[0056] The first group of low-voltage power modules performs DC / AC conversion, transferring energy to the high-voltage side of the first high-frequency transformer via the resonant cavity. The first group of high-voltage power modules performs AC / DC conversion via the rectifier bridge, then DC / AC conversion via the H-bridge, transferring energy to the second group of high-voltage power modules via the load reactance. The second group of high-voltage power modules performs AC / DC conversion via the H-bridge, and uses the energy storage test module to perform DC / AC conversion to connect to the second high-frequency transformer, transferring energy to the second group of low-voltage power modules. The second group of low-voltage power modules performs AC / DC conversion, sending the energy back to the DC test power supply, realizing the circulation of reactive power between the two groups of power modules, forming a closed loop.

[0057] To protect the two power modules and the energy storage test module, over- and under-voltage protection, over-current protection, over-temperature protection, IGBT drive fault protection, control board power-off protection, and contactor fault-related protection logic are added to the control board program.

[0058] To achieve full-power test verification of the power modules, the power is controlled by controlling the load reactance current. For the first group of high-voltage power module H-bridges, switching pulses are generated through a tuning system. For the second group of high-voltage power module H-bridges, the modulation wave is obtained by closed-loop control of the load reactance sampling current, current reference value, and the modulation wave of the previous H-bridge, thereby generating the switching pulses of the second group of high-voltage power module H-bridges.

[0059] The control chassis is powered by AC 220V and is connected to the control boards of the first group of power modules, the second group of power modules, and the energy storage test power module via optical fiber. The control chassis is equipped with an external touch screen, which is easy to operate and can monitor the module unlock status, voltage, IGBT temperature, IGBT drive fault signal, load reactance current sampling value, and can also manually set the control mode, current reference value, current loop PI parameter, overcurrent protection value, etc.

[0060] The topology schematic of the drag test system is as follows: Figure 4 As shown, the control method (equivalent to the control method for the drag test in the above embodiments) is as follows:

[0061] Sequentially switch on the power supply to the control box, switch on the DC test power supply to the test circuit, set the modulation mode of the first group of high-voltage power modules and the overcurrent protection setting of the load reactance on the touch screen, adjust the DC power supply voltage, and control the unlocking of the first group of low-voltage power modules.

[0062] After the voltage on the high and low voltage sides of the resonant cavity of the first high-frequency transformer stabilizes and the voltage of the DC capacitor of the first power high voltage module stabilizes, the H-bridge of the first power high voltage module is unlocked.

[0063] After the voltage at the bridge port of the first group of high-voltage power modules H-bridge stabilizes, the second group of high-voltage power modules H-bridge is unlocked.

[0064] After the DC capacitor voltage of the second group of high-voltage power modules stabilizes, the control energy storage test power module is unlocked, and the second group of low-voltage power modules is in an uncontrolled rectification state.

[0065] Change the load reactance current setting on the control touch screen, monitor the real-time effective value data of the load reactance current through the oscilloscope, and adjust the power according to the needs.

[0066] Power control strategies such as Figure 5 The logical steps are as follows:

[0067] First, based on the set value of the modulation index, the modulation wave of the first group of high-voltage power modules is generated, and the H-bridge switching pulse is generated through single-stage frequency doubling modulation.

[0068] The phase angle of the modulation wave of the first group of power high voltage modules is detected by a single-phase phase-locked loop, and the corresponding load reactance AC current reference is generated by using this phase angle and the effective value of the load reactance AC current reference.

[0069] The difference between the actual sampled value of the load reactance current and the reference value is calculated, and after being limited by the output of the PI controller, the first group of power high voltage module modulation wave feedforward is superimposed to generate the second group of power high voltage module modulation wave. The H-bridge switching pulse is generated by single-stage frequency doubling modulation.

[0070] Through the above-described scheme in the embodiments of this application, the power module can achieve the rated voltage and rated current operating conditions without a large-capacity load and power supply during power testing, which facilitates the evaluation of the power module and makes the test conditions easy to meet; the test process realizes power cycling, and the energy mainly exists in the form of reactive power, with less loss; each round of drag test can verify the performance of two sets of power modules, improving the testing efficiency.

[0071] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods of the various embodiments of this application.

[0072] This application also provides an architecture diagram of a control system for a drag test. Figure 6 This is an architecture diagram of the control system for a drag test according to an embodiment of this application; as shown below. Figure 6 As shown, it includes:

[0073] Closed loop 62 and control box 64;

[0074] The closed loop includes: a DC test power supply; a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module; and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein the first high-voltage power module and the second high-voltage power module are connected through a load reactance, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer;

[0075] The control box is connected to the first high-voltage power module and the second high-voltage power module via optical fibers. It is used to generate a first switching pulse and a second switching pulse that act on the first high-voltage power module and the second high-voltage power module, respectively. It is also used to control the drag test of the closed loop through the first switching pulse and the second switching pulse.

[0076] The system described above comprises a closed loop and a control chassis. The closed loop includes: a DC test power supply; a first low-voltage power module and a second low-voltage power module connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module; and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module. The first high-voltage power module and the second high-voltage power module are connected via a load reactor, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer. The control chassis is connected to the first high-voltage power module and the second high-voltage power module via optical fibers, and is used to generate a first switching pulse and a second switching pulse acting on the first high-voltage power module and the second high-voltage power module, respectively. It is also used to control the drag test of the closed loop using the first and second switching pulses. This embodiment solves the problem in the prior art of lacking a drag test control scheme for the power modules of power electronic transformers with single-phase power transmission, and achieves the technical effect of providing a safe, reliable, simple, and efficient drag test scheme for the power modules of power electronic transformers with single-phase power transmission.

[0077] In an exemplary embodiment, the control chassis is further configured to generate a first modulation wave of the first high-voltage power module and to generate a first switching pulse through the first modulation wave; the control chassis is further configured to receive a sampled current of the load reactance collected by a current sampling Hall sensor through a sampling interface, wherein the sampling Hall sensor is connected in series with the load reactance; the control chassis is further configured to detect the phase angle of the first modulation wave through a single-phase lock-in loop; and to generate a second switching pulse through the sampled current and the phase angle.

[0078] In one exemplary embodiment, the control chassis is further configured to determine the AC current reference corresponding to the load reactance by means of the phase angle; the control chassis is further configured to generate the second switching pulse by means of the sampled current and the AC current reference.

[0079] In an exemplary embodiment, the control chassis is further connected to the first low-voltage power module, the second low-voltage power module, and the energy storage test module via optical fibers; the control chassis is also used to control the unlocking of the target module, wherein the target module includes: the first low-voltage power module, the first high-voltage power module, the second high-voltage power module, and the energy storage test module.

[0080] In an exemplary embodiment, the control chassis is provided with a touch screen, which is used by the target object to set target information to the control chassis, wherein the target information includes: the modulation index for generating the first switching pulse and the overcurrent protection setting of the load reactance.

[0081] In one exemplary embodiment, the DC test power supply is connected to a three-phase AC power grid via a three-phase bridge converter, wherein the three-phase bridge converter is used to rectify the output of the three-phase AC power grid.

[0082] Embodiments of this application also provide a storage medium including a stored program, wherein the program executes any of the methods described above when it is run.

[0083] Optionally, in this embodiment, the storage medium may be configured to store program code for performing the following steps:

[0084] S1 generates a first switching pulse and a second switching pulse that act on the first power high voltage module and the second power high voltage module, respectively, by controlling the chassis;

[0085] S2, the closed-loop drag test is controlled by the first switching pulse and the second switching pulse; wherein, the closed-loop includes: a DC test power supply, a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module, and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein, the first high-voltage power module and the second high-voltage power module are connected by a load reactor, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer; the control chassis is connected to the first high-voltage power module and the second high-voltage power module respectively via optical fiber.

[0086] Embodiments of this application also provide an electronic device including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the steps in any of the above method embodiments.

[0087] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor and the input / output device is connected to the processor.

[0088] Optionally, in this embodiment, the processor can be configured to perform the following steps via a computer program:

[0089] S1 generates a first switching pulse and a second switching pulse that act on the first power high voltage module and the second power high voltage module, respectively, by controlling the chassis;

[0090] S2, the closed-loop drag test is controlled by the first switching pulse and the second switching pulse; wherein, the closed-loop includes: a DC test power supply, a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module, and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein, the first high-voltage power module and the second high-voltage power module are connected by a load reactor, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer; the control chassis is connected to the first high-voltage power module and the second high-voltage power module respectively via optical fiber.

[0091] Optionally, in this embodiment, the storage medium may include, but is not limited to, various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0092] Embodiments of this application also provide a computer program product, which includes a computer program that, when executed by a processor, implements the steps in any of the above method embodiments.

[0093] Embodiments of this application also provide another computer program product, including a non-volatile computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps in any of the above method embodiments.

[0094] Embodiments of this application also provide a computer program that includes computer instructions stored in a computer-readable storage medium; a processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the steps in any of the above method embodiments.

[0095] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0096] Obviously, those skilled in the art should understand that the modules or steps of this application described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented here, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, this application is not limited to any particular combination of hardware and software.

[0097] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. A control system for a drag test, characterized in that, include: Closed loop and control chassis; The closed loop includes: a DC test power supply; a first low-voltage power module and a second low-voltage power module respectively connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module; and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module; wherein the first high-voltage power module and the second high-voltage power module are connected through a load reactance, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer; The energy storage test module is used to absorb the power of the second high-voltage power module and to maintain the power balance of the test circuit when energy needs to be released. The H-bridge of the second high-voltage power module realizes AC / DC conversion. After DC / AC conversion using the energy storage test module, it is connected to the second high-frequency transformer to transmit energy to the second low-voltage power module. The control box is connected to the first high-voltage power module and the second high-voltage power module via optical fibers. It is used to generate a first switching pulse and a second switching pulse that act on the first high-voltage power module and the second high-voltage power module, respectively. It is also used to control the drag test of the closed loop through the first switching pulse and the second switching pulse.

2. The control system for the drag test according to claim 1, characterized in that, The control chassis is also used to generate a first modulation wave of the first power high voltage module, and to generate the first switching pulse through the first modulation wave; The control chassis is also used to receive the sampled current of the load reactance collected by the current sampling Hall sensor through a sampling interface, wherein the sampling Hall sensor is connected in series with the load reactance; The control chassis is also used to detect the phase angle of the first modulation wave through a single-phase phase-locked loop; and to generate the second switching pulse through the sampling current and the phase angle.

3. The control system for the drag test according to claim 2, characterized in that, The control chassis is also used to determine the AC current reference corresponding to the load reactance through the phase angle; The control chassis is also used to generate the second switching pulse using the sampled current and the AC current reference.

4. The control system for the drag test according to claim 1, characterized in that, The control box is also connected to the first low-voltage power module, the second low-voltage power module and the energy storage test module via optical fibers; The control chassis is also used to control the unlocking of the target module, wherein the target module includes: the first low-voltage power module, the first high-voltage power module, the second high-voltage power module, and the energy storage test module.

5. The control system for the drag test according to claim 1, characterized in that, The control chassis is equipped with a touch screen, which is used by the target object to set target information to the control chassis. The target information includes: the modulation index for generating the first switching pulse and the overcurrent protection setting of the load reactance.

6. The control system for the drag test according to claim 1, characterized in that, The DC test power supply is connected to the three-phase AC power grid through a three-phase bridge converter, wherein the three-phase bridge converter is used to rectify the output of the three-phase AC power grid.

7. A method for controlling a drag test, characterized in that, include: The control chassis generates a first switching pulse and a second switching pulse that act on the first power high voltage module and the second power high voltage module, respectively. The pull test of the closed loop is controlled by the first switch pulse and the second switch pulse; The closed loop includes: a DC test power supply; a first low-voltage power module and a second low-voltage power module connected to the DC test power supply; a first high-frequency transformer connected between the first low-voltage power module and the first high-voltage power module; and a second high-frequency transformer connected between the second low-voltage power module and the second high-voltage power module. The first high-voltage power module and the second high-voltage power module are connected via a load reactance, and an energy storage test module is also connected between the second high-voltage power module and the second high-frequency transformer. The control chassis is connected to the first high-voltage power module and the second high-voltage power module via optical fibers. The energy storage test module absorbs power from the second high-voltage power module and maintains the power balance of the test loop when energy needs to be released. The H-bridge of the second high-voltage power module performs AC / DC conversion, and the energy storage test module performs DC / AC conversion before connecting to the second high-frequency transformer to transmit energy to the second low-voltage power module.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein the program, when executed, performs the method described in claim 7.

9. An electronic device comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to execute the method of claim 7 through the computer program.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method of claim 7.

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