Voltage regulation method and device of DC-DC buck module and electronic equipment

Abstract

The application discloses a voltage regulation method and device of a DC-DC step-down module and electronic equipment. The method comprises the following steps: acquiring output currents respectively corresponding to a plurality of DC-DC step-down modules at a current time and input voltages respectively corresponding to the plurality of DC-DC step-down modules; determining a predicted load power of an LED screen in a future time period; determining a target bus voltage of a direct-current bus based on the predicted load power; determining voltage reference values respectively corresponding to the plurality of DC-DC step-down modules based on the output currents respectively corresponding to the plurality of DC-DC step-down modules, the input voltages respectively corresponding to the plurality of DC-DC step-down modules and the target bus voltage; and adjusting output voltages of the plurality of DC-DC step-down modules respectively by using the voltage reference values respectively corresponding to the plurality of DC-DC step-down modules. The application solves the technical problem of an unsatisfactory voltage regulation effect of a DC-DC step-down module in the related art.

Description

Technical Field

[0001] This application relates to the field of power systems, and more specifically, to a voltage regulation method, apparatus, and electronic device for a DC-DC step-down module. Background Technology

[0002] With the widespread application of LED (Light Emitting Diode) screens in outdoor advertising, stage performances, and sporting events, higher demands are placed on the energy efficiency, stability, and reliability of power supply systems. Related technologies employ a centralized DC power supply architecture, where AC power is converted to a unified DC bus voltage (e.g., 48V or 400V) through one or more central rectifier units. This bus voltage is then stepped down by multiple distributed DC-DC (Direct Current to Direct Current Converter) buck modules before being supplied to the LED enclosures. Therefore, improving the voltage regulation quality of the DC-DC buck modules is crucial for maintaining the power supply stability of the LED screen.

[0003] Related technologies employ fixed reference voltage control strategies based on local feedback or analog droop control methods to determine the voltage reference values ​​for each DC-DC buck module. However, these methods lack the ability to predict dynamic changes in the LED screen and cannot adaptively compensate for input voltage differences, resulting in insufficient accuracy and reasonableness of the determined voltage reference values. Therefore, these technologies suffer from the technical problem of unsatisfactory voltage regulation performance of the DC-DC buck modules due to the poor accuracy of the determined voltage reference values.

[0004] There is currently no effective solution to the above problems. Summary of the Invention

[0005] This application provides a voltage regulation method, apparatus, and electronic device for a DC-DC buck module, to at least solve the technical problem of unsatisfactory voltage regulation effect of DC-DC buck modules in related technologies.

[0006] According to one aspect of the embodiments of this application, a voltage regulation method for a DC-DC buck module is provided, comprising: acquiring the output current and input voltage of a plurality of DC-DC buck modules at a current moment, wherein the plurality of DC-DC buck modules are used to regulate the DC power transmitted from the DC bus and then supply it to an LED screen; determining the predicted load power of the LED screen in a future time period; determining the target bus voltage of the DC bus based on the predicted load power; determining the voltage reference value of the plurality of DC-DC buck modules based on the output current, input voltage, and target bus voltage of the plurality of DC-DC buck modules; and adjusting the output voltage of the plurality of DC-DC buck modules respectively using the voltage reference values ​​of the plurality of DC-DC buck modules.

[0007] According to another aspect of the embodiments of this application, a voltage regulation device for a DC-DC buck module is provided, comprising: a data acquisition module, configured to acquire the output current and input voltage of a plurality of DC-DC buck modules at the current moment, wherein the plurality of DC-DC buck modules are used to regulate the DC power transmitted from the DC bus and then provide it to an LED screen; a first determination module, configured to determine the predicted load power of the LED screen in a future time period; a second determination module, configured to determine the target bus voltage of the DC bus based on the predicted load power; a third determination module, configured to determine the voltage reference value of the plurality of DC-DC buck modules based on the output current, input voltage, and target bus voltage of the plurality of DC-DC buck modules; and an adjustment module, configured to adjust the output voltage of the plurality of DC-DC buck modules respectively using the voltage reference values ​​of the plurality of DC-DC buck modules.

[0008] According to another aspect of the embodiments of this application, a non-volatile storage medium is provided, which stores a plurality of instructions adapted for a voltage regulation method of a DC-DC buck module, any one of which is loaded by a processor.

[0009] According to another aspect of the embodiments of this application, an electronic device is provided, including: one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement any one of the voltage regulation methods of a DC-DC buck module.

[0010] According to another aspect of the embodiments of this application, a computer program product is provided, which, when executed on a data processing device, is adapted to perform the voltage regulation method steps of a DC-DC buck module.

[0011] In this embodiment, the output current and input voltage of multiple DC-DC step-down modules at the current moment are obtained. These multiple DC-DC step-down modules are used to regulate the DC power transmitted from the DC bus and supply it to the LED screen. The predicted load power of the LED screen for a future time period is determined. Based on the predicted load power, the target bus voltage of the DC bus is determined. Based on the output current, input voltage, and target bus voltage of the multiple DC-DC step-down modules, voltage reference values ​​are determined for each module. The output voltage of each DC-DC step-down module is adjusted using these voltage reference values. The goal is to obtain the output current and input voltage of the DC-DC buck module, combine them with the predicted load power of the LED screen, determine the voltage reference value of the DC-DC buck module, and use this reference value to adjust the output voltage of the DC-DC buck module. This achieves the technical effect of improving the voltage regulation quality of the DC-DC buck module by accurately determining the voltage reference value, thereby solving the technical problem of unsatisfactory voltage regulation effect of DC-DC buck modules in related technologies. Attached Figure Description

[0012] 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:

[0013] Figure 1 This is a flowchart of a voltage regulation method for a DC-DC buck module according to an embodiment of this application;

[0014] Figure 2 This is a structural block diagram of an optional low-harmonic DC centralized power supply system provided according to an embodiment of this application;

[0015] Figure 3 This is a flowchart of an optional DC bus voltage regulation method provided according to an embodiment of this application;

[0016] Figure 4 This is a schematic diagram of an optional DC-DC buck module voltage regulation device according to an embodiment of this application;

[0017] Figure 5 This is a structural diagram of an electronic device provided according to an embodiment of this application. Detailed Implementation

[0018] 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.

[0019] 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.

[0020] It should be noted that the information and data collected in this application (including but not limited to the output current and input voltage of multiple DC-DC step-down modules, and the brightness data of the LED screen, etc.) are information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, storage, use, processing, transmission, provision, disclosure, and application of this data all comply with relevant laws, regulations, and standards, and necessary confidentiality measures have been taken. This does not violate public order and good morals, and corresponding operation entry points are provided for users to choose to authorize or refuse. For example, interfaces are set up between this system and relevant users or organizations, providing users with corresponding operation entry points for them to choose to agree to or refuse the automated decision-making results; if the user chooses to refuse, the process proceeds to the expert decision-making stage.

[0021] According to an embodiment of this application, a method embodiment for voltage regulation of a DC-DC buck module is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0022] Figure 1 This is a flowchart illustrating a voltage regulation method for a DC-DC buck module according to an embodiment of this application, as shown below. Figure 1 As shown, the method includes the following steps:

[0023] Step S102: Obtain the output current and input voltage of the multiple DC-DC step-down modules at the current time. The multiple DC-DC step-down modules are used to adjust the DC power transmitted from the DC bus and then supply it to the LED screen.

[0024] It is understandable that by collecting the output current and input voltage of multiple DC-DC step-down modules in real time, a precise, dynamic, and global data foundation is provided for the intelligent calculation of voltage reference values, thus ensuring the stability, energy efficiency, and reliability of the LED screen power supply system.

[0025] In an optional embodiment, the method further includes: determining the total output current of the multiple DC-DC buck modules based on their respective output currents; determining a current adjustment command for the rectifier unit based on the total output current and the actual input current of the rectifier unit at the current moment; and adjusting the input current of the rectifier unit using the current adjustment command.

[0026] It can be understood that the total output current of multiple DC-DC buck modules is obtained by summing the output currents of each module. Based on the total output current and the actual input current of the rectifier unit at the current moment, a current regulation command for the rectifier unit is determined, and this command is used to adjust the input current of the rectifier unit. By using the total output current of multiple DC-DC buck modules as a feedforward signal, combined with the actual input current of the rectifier unit to form a closed-loop regulation, millisecond-level tracking of the rectifier unit's input current to dynamic load changes is achieved. This ensures that the input current waveform is in phase with the grid voltage, effectively suppressing the total harmonic distortion rate of the input current and eliminating the risk of neutral line overcurrent.

[0027] Optionally, the current regulation command of the rectifier unit can The following method is used to determine:

[0028]

[0029] in, For input current, This is the feedforward gain coefficient. This represents the instantaneous value of the total load current.

[0030] Optionally, the DC-DC buck module supports hot-swapping and has insertion detection and electronic fuse functions. Furthermore, the distributed DC-DC buck module array contains N+M DC-DC buck modules, of which M are redundant. The intelligent control unit monitors the health of each DC-DC buck module in real time, and automatically isolates and activates a redundant module to replace the faulty module when a DC-DC buck module fails.

[0031] Optionally, parameters such as input and output voltage, output current, temperature, on-state voltage drop of the switching transistor, and operating time of the DC-DC buck module can be collected in real time, and a health index H (0~1) of the DC-DC buck module can be calculated using fuzzy logic. When the health index H of a DC-DC buck module is lower than the threshold (e.g., 0.8), it is automatically marked as "sub-healthy". The intelligent control unit reallocates the voltage, reduces the load on the DC-DC buck module, and notifies maintenance personnel to prepare for replacement. If the health index continues to drop to 0.6, the system automatically isolates the DC-DC buck module and activates the backup DC-DC buck module.

[0032] Step S104: Determine the predicted load power of the LED screen for the future time period;

[0033] It is understandable that by using a future load power prediction mechanism based on the brightness data of the LED screen, the forward-looking, adaptive, and high-precision determination of the voltage reference value of the DC-DC step-down module is achieved, overcoming the shortcomings of traditional feedback control such as lag in response, inaccurate power distribution, and low energy efficiency, and ensuring the continuity of image display and color consistency of the LED screen.

[0034] Alternatively, a nonlinear mapping model of "brightness → power" for the LED screen can be established. Determine the predicted load power of the LED screen. Divide the brightness range into several intervals (e.g., 0~20%, 20~50%, 50~80%, 80~100%), determine the linear fitting function for each interval, and then obtain the nonlinear mapping model of "brightness → power" of the LED screen.

[0035] Alternatively, a neural network model can be used to determine the predicted load power of the LED screen. A lightweight convolutional neural network (CNN) or a long short-term memory (LSTM) network is used to train the mapping relationship between the input image features and the measured power output. The model parameters are adaptively adjusted according to the type of LED screen, the characteristics of the driver chip, the brightness-current response curve, and historical operating data to achieve high prediction accuracy of the predicted load power, which is especially suitable for complex dynamic scenes (such as rapid flashing and multi-color block switching).

[0036] In one optional embodiment, determining the predicted load power of the LED screen for a future time period includes: acquiring screen brightness data of the LED screen for a future time period; determining the average brightness of the LED screen for the future time period based on the screen brightness data; and determining the predicted load power based on the average brightness.

[0037] This can be understood as acquiring the screen brightness data for a future time period and determining the average brightness of the LED screen for that period based on this data. Then, a pre-established nonlinear mapping model between brightness and power is used based on the average brightness. The predicted load power of the LED screen over a future time period is determined by acquiring the screen's brightness data for that period and applying a high-precision "brightness → power" nonlinear mapping model. By predicting load power, the power supply system can respond proactively and accurately to load changes, improving the accuracy of voltage reference value determination results for DC-DC buck modules.

[0038] Optionally, a time-decrease weighted algorithm can be used to determine the average brightness of the LED screen over a future time period. The average brightness is determined as follows:

[0039]

[0040]

[0041] in, The average brightness over a future time period T. Let be the weight of the t-th time in the future time period T. This refers to the image brightness data at time t within a future time period T. This is the attenuation coefficient. Weight. The brightness decays exponentially over time, meaning that the brightness data of the image closer to the current moment is given higher weight, ensuring that the predicted load power has real-time responsiveness and noise resistance.

[0042] In one alternative embodiment, determining the predicted load power based on average brightness includes:

[0043] ,

[0044] in, The predicted load power under average brightness B, This serves as the reference power for the low-brightness region. This serves as the reference power for the medium brightness region. This serves as the reference power for the high-brightness region. , and These are the slope coefficients for the low-brightness, medium-brightness, and high-brightness regions, respectively. and This is the brightness segmentation threshold, used to divide the area into low brightness, medium brightness, and high brightness zones.

[0045] It is understandable that by constructing a three-segment linear piecewise nonlinear mapping model of "brightness → power" based on average brightness, This improves the prediction accuracy of load power, thereby providing a highly reliable and dynamically adaptable input basis for the voltage reference value of the DC-DC buck module, and overcoming problems such as voltage over-adjustment, power imbalance, and image flicker caused by prediction deviation.

[0046] Optionally, in the "brightness → power" nonlinear mapping model of the LED screen, the three slope coefficients , and The slope coefficients, corresponding to the low, medium, and high brightness operating ranges respectively, strictly adhere to the physical characteristics and energy efficiency laws of the LED driving system. < < In the low-brightness region, due to the startup delay of the driver IC (Integrated Circuit) and the LED threshold current effect, the power increases slowly with brightness, resulting in a slow slope coefficient. The minimum brightness; the medium brightness region is the high-efficiency linear operating range for LEDs, where the power increase per unit brightness increment is most significant, and the slope coefficient is [missing information]. Maximum; in the high-brightness region, due to the saturation of the drive circuit, increased conduction losses of the MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), and decreased heat dissipation efficiency, the system efficiency decays, and the power growth tends to level off, with a slope coefficient... It is smaller than the medium brightness area but still larger than the low brightness area.

[0047] Step S106: Determine the target bus voltage of the DC bus based on the predicted load power;

[0048] It is understandable that the target bus voltage of the DC bus is determined based on the predicted load power. The DC bus is used to distribute the DC power output from the rectifier unit to each DC-DC step-down module. The target bus voltage refers to the bus voltage that maximizes the overall system efficiency. By dynamically determining the DC bus voltage that maximizes the synergistic efficiency of the rectifier unit and the DC-DC modules, it is ensured that the DC-DC modules operate stably within their high-efficiency range across the entire load range, achieving high reliability, low heat generation, and flicker-free operation for the LED screen power supply.

[0049] In one optional embodiment, determining the target bus voltage of the DC bus based on the predicted load power includes: determining the total input current of the multiple DC-DC buck modules based on the input current corresponding to each of the multiple DC-DC buck modules; determining a first conversion efficiency of the multiple DC-DC buck modules based on the total input current and the predicted load power; and determining the target bus voltage based on the first conversion efficiency and a second conversion efficiency of the rectifier unit, wherein the rectifier unit is used to convert the AC power from the grid into DC power and supply it to the multiple DC-DC buck modules via the DC bus.

[0050] The target bus voltage of the DC bus is determined as follows: First, the total input current of the multiple DC-DC step-down modules is obtained by summing the input currents of each module. Second, based on the total input current and the predicted load power of the LED screen over a future time period, the first conversion efficiency of the multiple DC-DC step-down modules is determined. This first conversion efficiency characterizes the energy efficiency level of the DC-DC modules in converting the bus voltage to the output voltage required by the LED. Finally, the target bus voltage of the DC bus is determined based on the first conversion efficiency and the second conversion efficiency of the rectifier unit. This second conversion efficiency characterizes the conversion performance of the rectifier unit in converting AC grid power to DC power under the bus voltage. The rectifier unit converts AC power from the grid to DC power and supplies it to the multiple DC-DC step-down modules via the DC bus. By jointly optimizing the first conversion efficiency of the DC-DC modules and the second conversion efficiency of the rectifier unit, the target bus voltage of the DC bus is dynamically determined, maximizing overall energy efficiency, reducing switching losses under light loads, decreasing line voltage drop under heavy loads, and improving the response accuracy and operational economy of the power supply system under dynamic loads.

[0051] Optionally, the optimal bus voltage of the DC bus The following method is used to determine:

[0052]

[0053]

[0054]

[0055]

[0056] in, Represents the independent variable that makes the function reach its maximum value. For the highest conversion efficiency, For the second conversion efficiency, The bus voltage of the DC bus to be optimized. For overall efficiency, , and The constant coefficients, This represents the total input current of multiple DC-DC buck modules. The optimal bus voltage for the DC bus is determined using the method described above, based on which the overall system efficiency is maximized.

[0057] Optionally, the optimal bus voltage also needs to meet the constraint that "the lower limit of the bus voltage ensures the normal operation of multiple DC-DC step-down modules, and the upper limit meets the safety standard (such as 400 volts)".

[0058] Step S108: Based on the output current of each DC-DC step-down module, the input voltage of each DC-DC step-down module, and the target bus voltage, determine the voltage reference values ​​for each DC-DC step-down module.

[0059] It is understandable that by determining the voltage reference value of each DC-DC step-down module based on the output current, input voltage, and target bus voltage of multiple DC-DC step-down modules, the voltage regulation accuracy and system stability can be significantly improved, ensuring that the LED screen has consistent brightness, no dark areas, and no flicker under long-distance distributed power supply.

[0060] In one optional embodiment, based on the output current of each of the multiple DC-DC buck modules, the input voltage of each of the multiple DC-DC buck modules, and the target bus voltage, the voltage reference value corresponding to each of the multiple DC-DC buck modules is determined, including: determining the average output current of each DC-DC buck module based on the output current of each of the multiple DC-DC buck modules and the number of multiple DC-DC buck modules; and determining the voltage reference value corresponding to each of the multiple DC-DC buck modules based on the target bus voltage, the average output current, the output current of each of the multiple DC-DC buck modules, and the input voltage of each of the multiple DC-DC buck modules.

[0061] It can be understood that the total output current of multiple DC-DC buck modules is obtained by summing the output currents of each module. The average output current of each module is then calculated by dividing the total output current by the number of modules. Based on the target bus voltage, the average output current, and the output current and input voltage of each module, a voltage reference value is calculated for each module. By calculating the average output current based on the total output current and integrating multi-dimensional feedback information from the target bus voltage, the output current of each module, and the input voltage, a personalized voltage reference value is accurately generated, improving the voltage stability and brightness consistency of LED screens under distributed power supply.

[0062] In one optional embodiment, based on the target bus voltage, average output current, output current corresponding to each of the multiple DC-DC buck modules, and input voltage corresponding to each of the multiple DC-DC buck modules, a voltage reference value corresponding to each of the multiple DC-DC buck modules is determined, including: for any DC-DC buck module among the multiple DC-DC buck modules, a voltage reference value for any DC-DC buck module is determined based on the output current of any DC-DC buck module, the input voltage of any DC-DC buck module, the target bus voltage, and the average output current;

[0063] ,

[0064] in, For any DC-DC step-down module i Voltage reference value, For the target bus voltage, For the current sharing proportional gain, The average output current, For any DC-DC step-down module i The output current, To compensate for voltage drop gain, For any DC-DC step-down module i The input voltage;

[0065] By determining the voltage reference value of any DC-DC buck module, the voltage reference values ​​corresponding to multiple DC-DC buck modules are determined respectively.

[0066] It is understandable that, in the method of determining the voltage reference value of any of the above DC-DC buck modules, The current sharing proportional gain, measured in V / I (volts per ampere), is used to compensate for current deviations, enabling low-output DC-DC buck modules to increase the voltage reference value and thus increase the output. The voltage drop compensation gain is a dimensionless constant used to offset input voltage drops caused by line impedance, preventing the remote DC-DC buck module from current limiting or becoming unstable due to undervoltage. This is achieved by introducing a current sharing proportional gain. With voltage drop compensation gain The dual closed-loop collaborative compensation mechanism accurately and dynamically generates voltage reference values ​​for each DC-DC step-down module, improves the voltage regulation capability of the DC-DC step-down module, eliminates the risk of uneven LED screen brightness and DC-DC step-down module overload, and achieves high stability and high consistency voltage regulation under long-distance distributed power supply.

[0067] Step S110: Using the voltage reference values ​​corresponding to the multiple DC-DC step-down modules respectively, the output voltage of the multiple DC-DC step-down modules is adjusted respectively.

[0068] It is understandable that by applying precisely calculated voltage reference values ​​to each DC-DC step-down module, the output voltage of the DC-DC step-down module can be accurately controlled, ensuring uniform brightness, no dark areas, and no flicker across the entire LED screen, thereby improving the display quality and operational stability of the LED screen.

[0069] Through the above steps S102 to S110, the goal is to obtain the output current and input voltage of the DC-DC buck module, combine them with the predicted load power of the LED screen, determine the voltage reference value of the DC-DC buck module, and use this reference value to adjust the output voltage of the DC-DC buck module. This achieves the technical effect of improving the voltage regulation quality of the DC-DC buck module by accurately determining the voltage reference value, thereby solving the technical problem of unsatisfactory voltage regulation effect of the DC-DC buck module in related technologies.

[0070] Based on the above embodiments and optional embodiments, this application proposes an implementation method for an optional DC-DC step-down module voltage regulation method, which can be understood as a low-harmonic DC centralized power supply system for LED screens.

[0071] LED screens typically employ a distributed power supply scheme, where each LED cabinet is equipped with an independent AC-DC switching power supply. This power supply scheme has the following problems: (1) Severe harmonic pollution. LED loads are typical nonlinear loads, and the simultaneous operation of a large number of distributed switching power supplies can lead to a total harmonic distortion (THD) of over 30% in the input current. In particular, the third harmonic is superimposed on the neutral line, causing the neutral line current to far exceed the phase line current, posing a fire hazard. (2) Low energy efficiency. Traditional DC power supply systems use a fixed DC bus voltage (such as 48 volts), which cannot be dynamically adjusted according to load changes, resulting in a significant decrease in conversion efficiency under light load. (3) Inability to cope with sudden load changes. When the brightness of the LED screen changes drastically, the load power jumps instantaneously, and the traditional power supply responds with lag, which may cause the DC bus voltage to drop or even shut down for protection.

[0072] To address the above issues, a low-harmonic DC centralized power supply system for LED large screens is proposed. Figure 2 This is a structural block diagram of an optional low-harmonic DC centralized power supply system provided according to an embodiment of this application, such as... Figure 2As shown, the low-harmonic DC centralized power supply system for LED screens includes a low-harmonic rectifier unit, a distributed DC-DC step-down module array, an intelligent control unit, and a digital communication network. The low-harmonic rectifier unit converts mains power (from the city's public power grid) into a DC bus voltage, using an improved modulation strategy to ensure the input current THD is ≤5%. The adjustable DC bus receives commands from the intelligent control unit and dynamically adjusts the DC bus voltage (typically 200V~400V) to optimize energy efficiency. The distributed DC-DC step-down module array, deployed near the LED screen, steps down the DC bus voltage to the voltage required by the LEDs; each DC-DC step-down module regulates its voltage via digital communication. The intelligent control unit is responsible for LED screen brightness resolution, load power prediction, DC bus voltage regulation, DC-DC step-down module voltage regulation, DC-DC step-down module health assessment, and fault handling. The digital communication network connects each DC-DC step-down module to the intelligent control unit, transmitting voltage regulation commands, status feedback, and health data.

[0073] The low harmonic rectifier unit adopts a three-phase active front end rectifier (AFE) and designs an improved SVPWM (Space Vector Pulse Width Modulation) modulation strategy for the load characteristics of LED screens to achieve adjustment of the input current of the rectifier unit, adaptive dead-time compensation, and adaptive filtering of grid distortion.

[0074] LED screen load current feedforward compensation. The instantaneous value of the total load current (i.e., the total output current of multiple DC-DC buck modules) fed back by each DC-DC buck module in real time is acquired via a high-speed communication interface and fed forward to the AFE's inner current loop controller. Based on the instantaneous value of the total load current and the actual input current of the AFE, the current adjustment command for the rectifier unit is determined. . The following method is used to determine:

[0075]

[0076] in, For input current, This is the feedforward gain coefficient. This represents the instantaneous value of the total load current.

[0077] When the brightness of the LED screen changes abruptly, the AFE can adjust the PWM (Pulse Width Modulation) duty cycle in advance to suppress DC bus voltage fluctuations.

[0078] Adaptive dead-time compensation. By real-time detection of the switching transistor's on-state voltage drop and output current direction, the dead-time is dynamically adjusted to reduce low-order harmonics introduced by the dead time.

[0079] Adaptive filtering for grid distortion. A digital phase-locked loop (PLL) is used to detect the degree of grid voltage distortion in real time and automatically adjust the cutoff frequency of the filter loop to maintain a sinusoidal input current.

[0080] The adjustable DC bus voltage is adjusted in the following manner. Figure 3 This is a flowchart of an optional DC bus voltage regulation method provided according to an embodiment of this application, such as... Figure 3 As shown, the steps of the DC bus voltage regulation method include:

[0081] First, the brightness-load relationship is modeled.

[0082] By pre-calibrating, a mapping relationship between LED screen brightness and load current / power is established, which is used to determine the predicted load power of the LED screen. The above mapping relationship can be characterized by establishing a nonlinear mapping model of "brightness → power" for LED screens, or it can be constructed using a neural network model.

[0083] Secondly, the predicted load power of the LED screen.

[0084] The intelligent control unit analyzes video signals (DMX (Digital Multiplex) / Art-Net (Art-Net Protocol) or HDMI (High-Definition Multimedia Interface) / DP (Display Port) video streams) to obtain brightness data for several future frames (i.e., a future time period, such as 50-200 milliseconds). Based on this brightness data, and using the aforementioned mapping relationship, it determines the predicted load power of the LED screen. .

[0085] Then, the optimal bus voltage (i.e., the target bus voltage) of the DC bus is determined.

[0086] Optimal bus voltage of DC bus The following method is used to determine:

[0087]

[0088]

[0089]

[0090]

[0091] in, Represents the independent variable that makes the function reach its maximum value. For the highest conversion efficiency, For the second conversion efficiency, The bus voltage of the DC bus to be optimized. For overall efficiency, , and The constant coefficients, This represents the total input current of multiple DC-DC buck modules. The optimal bus voltage for the DC bus is determined using the method described above, based on which the overall system efficiency is maximized.

[0092] At the same time, the optimal bus voltage also needs to meet the constraint that "the lower limit of the bus voltage ensures the normal operation of multiple DC-DC step-down modules, and the upper limit meets the safety standard (such as 400 volts)".

[0093] Finally, voltage regulation is executed.

[0094] The intelligent control unit sends DC bus voltage adjustment commands to the rectifier unit via digital communication. The adjustment process employs a slow-start strategy to avoid voltage surges impacting the LED screen. Through this process, the DC bus voltage is reduced (e.g., to 200 volts) when the LED screen is lightly loaded, reducing switching losses; and the DC bus voltage is increased (e.g., to 380 volts) when the LED screen is heavily loaded, reducing transmission line losses.

[0095] To address the distributed voltage drop issue in long-distance power supply, a distributed voltage regulation protocol based on digital communication is proposed. This protocol eliminates the need for direct communication between modules, instead relying on centralized coordination by an intelligent control unit, thereby improving regulation accuracy.

[0096] Multiple DC-DC step-down modules are connected in parallel and deployed near the LED screen (e.g., one DC-DC step-down module for every 10-20 LED enclosures). The DC-DC step-down modules communicate with the intelligent control unit via CAN (Controller Area Network) / RS485 bus, forming a distributed power supply network. The intelligent control unit periodically samples the output current of each DC-DC step-down module. and input voltage .

[0097] Calculate the average output current of the DC-DC buck module , where N is the number of multiple DC-DC buck modules.

[0098] Calculate the voltage reference value for each DC-DC buck module. This enables active voltage regulation.

[0099] This mechanism ensures that even when DC-DC step-down modules at different distances are connected in parallel, each DC-DC step-down module can still bear the load evenly, avoiding overload or undervoltage of the remote DC-DC step-down module.

[0100] Meanwhile, the DC-DC buck module supports hot-swapping and has insertion detection and electronic fuse functions. Furthermore, the distributed DC-DC buck module array contains N+M DC-DC buck modules, of which M are redundant. The intelligent control unit monitors the health of each DC-DC buck module in real time, and automatically isolates and activates a redundant module to replace the faulty module when a DC-DC buck module fails.

[0101] Health assessment of DC-DC buck modules.

[0102] The system collects real-time parameters such as input and output voltage, output current, temperature, on-state voltage drop of the switching transistor, and operating time of the DC-DC buck module. Fuzzy logic is used to calculate the health index H (0~1) of the DC-DC buck module. When the health index H of a DC-DC buck module falls below a threshold (e.g., 0.8), it is automatically marked as "sub-healthy." The intelligent control unit reallocates the voltage, reducing the load on the DC-DC buck module, and simultaneously notifies maintenance personnel to prepare for replacement. If the health index continues to drop to 0.6, the system automatically isolates the DC-DC buck module and activates a backup DC-DC buck module.

[0103] In low-harmonic DC centralized power supply systems for LED screens, the intelligent control unit is the "brain" of the system, responsible for the following core functions: LED screen image analysis and predicted load power. It analyzes video signals and predicts the predicted load power for future time periods. DC bus voltage regulation. Based on the predicted load power, it calculates and distributes the optimal bus voltage. DC-DC buck module voltage regulation. It collects the output current and input voltage of each DC-DC buck module and executes the voltage regulation process. Health monitoring. It evaluates the health index of each DC-DC buck module and performs active redundancy switching. Fault handling. When a DC-DC buck module fault is detected, it immediately isolates and calls upon redundant modules. Remote monitoring. It supports log recording, firmware upgrades, and cloud data uploads.

[0104] Here is Implementation Example 1: Small-scale activity (30kW, dynamic DC bus voltage regulation verification).

[0105] An outdoor music festival needs to set up a 30m... 2(Square meter) LED secondary screen, power approximately 30kW. System configuration: single 30kW AFE rectifier unit, six 5kW DC-DC step-down modules (N+1 redundancy), employing dynamic DC bus voltage regulation. On-site measurements showed: during light load periods (dim screen), the DC bus voltage automatically drops to 220V, improving efficiency by 12%; during heavy load periods (bright screen), the DC bus voltage rises to 380V, and the total harmonic distortion (THD) of the input current drawn by the AFE rectifier unit from the grid side is 4.1%. During brightness fluctuations, the DC bus voltage fluctuation is <3%.

[0106] Here is implementation example 2: large-scale opening ceremony (200kW, distributed voltage drop compensation verification).

[0107] A large-scale event requires the installation of an ultra-wide LED screen with a power of 200kW, located 300m away. System configuration: a 200kW WAFE rectifier unit at the front end, dynamic DC bus voltage regulation (200~380V), and eight 25kW DC-DC step-down modules distributed on both sides of the LED screen, employing a distributed voltage regulation protocol. Actual measurements showed that the voltage deviation between the far-end and near-end DC-DC step-down modules was <5%, and the input voltage deviation of each DC-DC step-down module was <8V, indicating effective voltage regulation. Compared to other voltage regulation schemes, the overload risk of the far-end DC-DC step-down modules was reduced by 80%.

[0108] The above optional implementation methods achieve at least the following effects: By employing an AFE-improved SVPWM modulation strategy, the input current THD is ensured to be ≤5%, eliminating the fire hazard caused by neutral wire overcurrent. The optimal DC bus voltage is dynamically determined based on the predicted load power of the LED screen. Under light load, the system reduces the DC bus voltage to decrease switching losses; under heavy load, it increases the DC bus voltage to decrease line losses, resulting in an overall energy efficiency improvement of 8%~15% compared to a fixed DC bus voltage solution. A distributed voltage regulation protocol enables voltage regulation of DC-DC step-down modules at different distances, preventing undervoltage in remote DC-DC step-down modules. An N+M redundancy architecture, combined with health index prediction, enables early fault prevention and seamless switching, ensuring the continuity of the LED screen display.

[0109] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0110] This embodiment also provides a voltage regulation device for a DC-DC step-down module, which is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the terms "module" and "device" can refer to a combination of software and / or hardware that performs a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0111] According to an embodiment of this application, an apparatus embodiment for implementing a voltage regulation method for a DC-DC buck module is also provided. Figure 4 This is a schematic diagram of an optional DC-DC buck module voltage regulation device according to an embodiment of this application, as shown below. Figure 4 As shown, the voltage regulation device of the above-mentioned DC-DC step-down module includes a data acquisition module 402, a first determination module 404, a second determination module 406, a third determination module 408, and an adjustment module 410. The device will be described below.

[0112] The data acquisition module 402 is used to acquire the output current of the multiple DC-DC step-down modules and the input voltage of the multiple DC-DC step-down modules at the current moment. The multiple DC-DC step-down modules are used to adjust the DC power transmitted from the DC bus and then supply it to the LED screen.

[0113] The first determining module 404 is connected to the data acquisition module 402 and is used to determine the predicted load power of the LED screen in the future time period.

[0114] The second determining module 406, connected to the first determining module 404, is used to determine the target bus voltage of the DC bus based on the predicted load power.

[0115] The third determining module 408, connected to the second determining module 406, is used to determine the voltage reference values ​​corresponding to the multiple DC-DC step-down modules based on the output current corresponding to the multiple DC-DC step-down modules, the input voltage corresponding to the multiple DC-DC step-down modules, and the target bus voltage.

[0116] The adjustment module 410, connected to the third determining module 408, is used to adjust the output voltage of the multiple DC-DC step-down modules by using the voltage reference values ​​corresponding to the multiple DC-DC step-down modules respectively.

[0117] The voltage regulation device for a DC-DC buck module provided in this application embodiment achieves the purpose of obtaining the output current and input voltage of the DC-DC buck module, and determining the voltage reference value of the DC-DC buck module by combining the predicted load power of the LED screen, and using the reference value to regulate the output voltage of the DC-DC buck module. This achieves the technical effect of improving the voltage regulation quality of the DC-DC buck module by accurately determining the voltage reference value of the DC-DC buck module, thereby solving the technical problem of unsatisfactory voltage regulation effect of DC-DC buck modules in related technologies.

[0118] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0119] It should be noted that the data acquisition module 402, the first determining module 404, the second determining module 406, the third determining module 408, and the adjustment module 410 correspond to steps S102 to S110 in the embodiments. The instances and application scenarios implemented by the above modules and corresponding steps are the same, but are not limited to the content disclosed in the above embodiments. It should be noted that the above modules, as part of the device, can run in a computer terminal.

[0120] It should be noted that the optional or preferred implementation methods of this embodiment can be found in the relevant descriptions in the embodiments, and will not be repeated here.

[0121] The voltage regulation device of the aforementioned DC-DC step-down module may further include a processor and a memory. The data acquisition module 402, the first determination module 404, the second determination module 406, the third determination module 408, the regulation module 410, etc., are all stored in the memory as program units, and the processor executes the aforementioned program units stored in the memory to realize the corresponding functions.

[0122] The processor contains a core that retrieves the corresponding program unit from memory. One or more cores may be configured. Memory may include non-persistent memory in computer-readable media, random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory includes at least one memory chip.

[0123] This application provides a non-volatile storage medium storing a program that, when executed by a processor, implements a voltage regulation method for a DC-DC buck module.

[0124] This application provides an electronic device. Figure 5 This is a structural diagram of an electronic device provided according to an embodiment of this application. For example... Figure 5 As shown, the electronic device may include: one or more ( Figure 5 (Only one is shown in the document) Processor 502, memory 504, memory controller, and peripheral interface, wherein the peripheral interface is connected to the radio frequency module, audio module, and display. The electronic device includes a processor, memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs the following steps: obtaining the output current and input voltage of each of the multiple DC-DC buck modules at the current moment, wherein the multiple DC-DC buck modules are used to regulate the DC power transmitted from the DC bus and provide it to the LED screen; determining the predicted load power of the LED screen for a future time period; determining the target bus voltage of the DC bus based on the predicted load power; determining the voltage reference values ​​of each of the multiple DC-DC buck modules based on the output current, input voltage, and target bus voltage; and adjusting the output voltage of each of the multiple DC-DC buck modules using the voltage reference values. The device in this document could be a server, PC, etc.

[0125] This application also provides a computer program product, which, when executed on a data processing device, is suitable for executing an initialization program with the following method steps: obtaining the output current and input voltage of a plurality of DC-DC buck modules at the current moment, wherein the plurality of DC-DC buck modules are used to regulate the DC power transmitted from the DC bus and provide it to the LED screen; determining the predicted load power of the LED screen in a future time period; determining the target bus voltage of the DC bus based on the predicted load power; determining the voltage reference value of the plurality of DC-DC buck modules based on the output current, input voltage, and target bus voltage of the plurality of DC-DC buck modules; and adjusting the output voltage of the plurality of DC-DC buck modules using the voltage reference values ​​of the plurality of DC-DC buck modules.

[0126] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0127] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0128] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0129] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0130] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0131] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0132] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0133] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0134] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0135] The above are merely embodiments of this application and are not intended to limit the scope of 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 spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A voltage regulation method for a DC-DC buck module, characterized in that, include: The output current of each of the multiple DC-DC step-down modules and the input voltage of each of the multiple DC-DC step-down modules are obtained at the current moment. The multiple DC-DC step-down modules are used to adjust the DC power transmitted from the DC bus and then supply it to the LED screen. Determine the predicted load power of the LED screen for a future time period; Based on the predicted load power, the target bus voltage of the DC bus is determined; Based on the output current of the plurality of DC-DC step-down modules, the input voltage of the plurality of DC-DC step-down modules, and the target bus voltage, the voltage reference values ​​corresponding to the plurality of DC-DC step-down modules are determined. The output voltage of each of the multiple DC-DC step-down modules is adjusted using the voltage reference values ​​corresponding to those modules.

2. The method according to claim 1, characterized in that, Determining the predicted load power of the LED screen for a future time period includes: Obtain the screen brightness data of the LED screen in the future time period; Based on the image brightness data, the average brightness of the LED screen in the future time period is determined; The predicted load power is determined based on the average brightness.

3. The method according to claim 2, characterized in that, Determining the predicted load power based on the average brightness includes: ， in, The predicted load power is given by the average brightness B. This serves as the reference power for the low-brightness region. This serves as the reference power for the medium brightness region. This serves as the reference power for the high-brightness region. , and These are the slope coefficients for the low-brightness, medium-brightness, and high-brightness regions, respectively. and This is the brightness segmentation threshold, used to divide the area into low brightness, medium brightness, and high brightness zones.

4. The method according to claim 1, characterized in that, Determining the target bus voltage of the DC bus based on the predicted load power includes: The total input current of the multiple DC-DC buck modules is determined based on their respective input currents. Based on the total input current and the predicted load power, the first conversion efficiency of the plurality of DC-DC buck modules is determined; Based on the first conversion efficiency and the second conversion efficiency of the rectifier unit, the target bus voltage is determined, wherein the rectifier unit is used to convert the AC power of the power grid into DC power and provide it to the plurality of DC-DC step-down modules through the DC bus.

5. The method according to claim 1, characterized in that, The step of determining the voltage reference values ​​for each of the plurality of DC-DC buck modules based on their respective output currents, input voltages, and target bus voltages includes: Based on the output current corresponding to each of the plurality of DC-DC buck modules and the number of the plurality of DC-DC buck modules, the average output current of the DC-DC buck module is determined; Based on the target bus voltage, the average output current, the output current corresponding to each of the plurality of DC-DC buck modules, and the input voltage corresponding to each of the plurality of DC-DC buck modules, the voltage reference values ​​corresponding to each of the plurality of DC-DC buck modules are determined.

6. The method according to claim 5, characterized in that, The step of determining the voltage reference values ​​for each of the multiple DC-DC buck modules based on the target bus voltage, the average output current, the output current corresponding to each of the multiple DC-DC buck modules, and the input voltage corresponding to each of the multiple DC-DC buck modules includes: For any one of the plurality of DC-DC buck modules, a voltage reference value for the DC-DC buck module is determined based on the output current of the DC-DC buck module, the input voltage of the DC-DC buck module, the target bus voltage, and the average output current. ， in, For any DC-DC step-down module i Voltage reference value, The target bus voltage, For the current sharing proportional gain, The average output current is... For any DC-DC step-down module i The output current, To compensate for voltage drop gain, For any DC-DC step-down module i The input voltage; The voltage reference values ​​for each of the multiple DC-DC step-down modules are determined by using the method of determining the voltage reference value of any one of the DC-DC step-down modules.

7. The method according to claim 1, characterized in that, The method further includes: Based on the output current of each of the multiple DC-DC buck modules, the total output current of the multiple DC-DC buck modules is determined. Based on the total output current and the actual input current of the rectifier unit at the current moment, the current adjustment command of the rectifier unit is determined; The input current of the rectifier unit is adjusted using the current adjustment command.

8. A voltage regulation device for a DC-DC step-down module, characterized in that, include: The data acquisition module is used to acquire the output current of the multiple DC-DC step-down modules at the current moment, and the input voltage of the multiple DC-DC step-down modules, wherein the multiple DC-DC step-down modules are used to adjust the DC power transmitted from the DC bus and then provide it to the LED screen. The first determining module is used to determine the predicted load power of the LED screen in a future time period; The second determining module is used to determine the target bus voltage of the DC bus based on the predicted load power; The third determining module is used to determine the voltage reference values ​​corresponding to the plurality of DC-DC step-down modules based on the output current corresponding to the plurality of DC-DC step-down modules, the input voltage corresponding to the plurality of DC-DC step-down modules, and the target bus voltage. The adjustment module is used to adjust the output voltage of the plurality of DC-DC step-down modules respectively using the voltage reference values ​​corresponding to the plurality of DC-DC step-down modules.

9. A non-volatile storage medium, characterized in that, The non-volatile storage medium stores multiple instructions, which are adapted to be loaded by a processor and executed by the processor to perform the voltage regulation method of the DC-DC buck module according to any one of claims 1 to 7.

10. An electronic device, characterized in that, include: One or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to implement the voltage regulation method of the DC-DC buck module according to any one of claims 1 to 7.

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