Photovoltaic bus voltage stabilization method and device, electronic equipment and storage medium

Abstract

This application provides a photovoltaic bus voltage stabilization method, device, electronic device, and storage medium. The method includes: acquiring the current bus voltage and the current photovoltaic voltage; calculating the deviation of the current bus voltage from a preset bus voltage using a multi-channel voltage control loop to obtain an upper limit and a lower limit for the current command to adapt to the deviation; determining an appropriate initial current command based on the current photovoltaic voltage; constraining the initial current command according to the upper and lower limits to obtain a target current command; and controlling the boost converter to operate according to the target current command to control the bus voltage. In the event of energy storage unit failure, this solution uses a multi-channel voltage control loop to match the initial current command to the real-time operating conditions of the bus voltage and dynamically constrains the initial current command based on the real-time deviation of the bus voltage, thereby controlling the bus voltage within a safe range and improving power supply stability.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a photovoltaic bus voltage stabilization method, apparatus, electronic device and storage medium. Background Technology

[0002] In areas without grid access or with unstable grids (such as mountainous areas, islands, and deserts), photovoltaic systems, as the main energy source, need to independently maintain the DC bus voltage stability to ensure stable load operation when there is no energy storage or when energy storage fails.

[0003] In related technologies, energy storage units are used to stabilize and control the voltage of photovoltaic systems.

[0004] However, this method can lead to low power supply stability of the photovoltaic system when the energy storage unit fails. Summary of the Invention

[0005] The photovoltaic bus voltage stabilization method, apparatus, electronic equipment, and storage medium provided in this application are used to improve power supply stability.

[0006] In a first aspect, embodiments of this application provide a photovoltaic bus voltage stabilization method, comprising: acquiring the current bus voltage and the current photovoltaic voltage; calculating the deviation of the current bus voltage from a preset bus voltage through a multi-channel voltage control loop to obtain an upper limit value and a lower limit value of the current command to adapt to the deviation; determining an adapted initial current command based on the current photovoltaic voltage; constraining the initial current command based on the upper limit value and the lower limit value of the current command to obtain a target current command; and controlling the operation of a boost converter according to the target current command to control the bus voltage.

[0007] In one possible implementation, the multi-channel voltage control loop includes: a fast upper limit control loop, a main voltage control loop, and a slow lower limit control loop; the deviation of the current bus voltage from a preset bus voltage is calculated by the multi-channel voltage control loop to obtain an upper limit and a lower limit of current command adapted to the deviation, including: determining the voltage range of each voltage control loop; allocating voltage deviations to the multi-channel voltage control loop according to the voltage range of each voltage control loop and the preset bus voltage to obtain multiple voltage deviation thresholds; and calculating the deviation of the current bus voltage from the preset bus voltage by the multi-channel voltage control loop according to the multiple voltage deviation thresholds to obtain an upper limit and a lower limit of current command adapted to the deviation.

[0008] In one possible implementation, based on the plurality of voltage deviation thresholds, the deviation of the current bus voltage from a preset bus voltage is calculated by a multi-channel voltage control loop to obtain an upper limit and a lower limit of the current command adapted to the deviation. This includes: calculating a first current control quantity and a second current control quantity based on the deviation of the current bus voltage from the corresponding voltage deviation thresholds using the fast upper limit control loop and the main voltage control loop, respectively; determining the minimum value between the first current control quantity and the second current control quantity as the upper limit of the current command; and calculating the lower limit of the current command based on the deviation of the current bus voltage from the corresponding voltage deviation thresholds using the slow lower limit control loop.

[0009] In one possible implementation, the multi-channel voltage control loop includes a maximum power point tracking (MPPT) voltage loop; determining an appropriate initial current command based on the current photovoltaic voltage includes: searching for the maximum photovoltaic power corresponding to the current photovoltaic voltage through the MPPT voltage loop; and determining the initial current command based on a current that matches the maximum photovoltaic power.

[0010] In one possible implementation, constraining the initial current command according to the upper limit and lower limit of the current command to obtain a target current command includes: determining the lower limit of the current command as the target current command in response to the lower limit being greater than or equal to the upper limit of the current command; and restricting the initial current command to a value between the upper limit and the lower limit of the current command in response to the lower limit being less than the upper limit of the current command, thereby obtaining the target current command.

[0011] In one possible implementation, controlling the operation of the boost converter according to the target current command includes: acquiring the current inductor current of the boost converter; determining the current difference between the target current command and the current inductor current; performing proportional-integral adjustment calculation on the current difference through the current inner loop to obtain a drive control signal; and controlling the on / off state of the boost converter through the drive control signal, thereby controlling the operation of the boost converter.

[0012] In one possible implementation, a drive control signal is obtained by performing proportional-integral adjustment on the current difference through an inner current loop. This includes: performing proportional calculation on the current difference through the inner current loop to compensate for dynamic deviations, and performing integral calculation to eliminate steady-state current errors, thereby obtaining a current adjustment reference value; generating a carrier signal with a fixed frequency and linearly varying amplitude according to the internal timing circuit of the boost converter; comparing the amplitude of the current adjustment reference value with that of the carrier signal, outputting a high level when the current adjustment reference value is greater than or equal to the amplitude of the carrier signal, and outputting a low level when the current adjustment reference value is less than the amplitude of the carrier signal, thereby obtaining a pulse width modulation signal with an adjustable duty cycle; and determining the pulse width modulation signal as the drive control signal.

[0013] Secondly, embodiments of this application provide a photovoltaic bus voltage stabilization device, comprising: a data acquisition module for acquiring the current bus voltage and the current photovoltaic voltage; a calculation module for calculating the deviation of the current bus voltage from a preset bus voltage through a multi-channel voltage control loop, thereby obtaining an upper limit value and a lower limit value of the current command to adapt to the deviation; a determination module for determining an adapted initial current command based on the current photovoltaic voltage; an execution module for constraining the initial current command based on the upper limit value and the lower limit value of the current command to obtain a target current command; and a control module for controlling the operation of a boost converter according to the target current command to control the bus voltage.

[0014] In one possible implementation, the multi-channel voltage control loop includes: a fast upper limit control loop, a main voltage control loop, and a slow lower limit control loop; the calculation module is specifically used to determine the voltage range of each of the voltage control loops; the calculation module is further used to perform voltage deviation allocation on the multi-channel voltage control loops according to the voltage range of each of the voltage control loops and the preset bus voltage, to obtain multiple voltage deviation thresholds; the calculation module is further used to calculate the degree of deviation of the current bus voltage from the preset bus voltage through the multi-channel voltage control loops according to the multiple voltage deviation thresholds, to obtain an upper limit value and a lower limit value of the current command adapted to the degree of deviation.

[0015] In one possible implementation, the calculation module is further configured to calculate, through the fast upper limit control loop and the main voltage control loop, respectively, the degree of deviation between the corresponding voltage deviation threshold and the current bus voltage to obtain a first current control quantity and a second current control quantity; the calculation module is further configured to determine the minimum value of the first current control quantity and the second current control quantity as the upper limit value of the current command; the calculation module is further configured to calculate, through the slow lower limit control loop, the degree of deviation between the corresponding voltage deviation threshold and the current bus voltage to obtain the lower limit value of the current command.

[0016] In one possible implementation, the multi-channel voltage control loop includes a maximum power point tracking (MPPT) voltage loop; the determining module is specifically configured to search for the maximum photovoltaic power corresponding to the current photovoltaic voltage through the MPPT voltage loop; the determining module is further configured to determine the initial current command based on the current matching the maximum photovoltaic power.

[0017] In one possible implementation, the execution module is specifically configured to determine the lower limit of the current command as the target current command in response to the lower limit of the current command being greater than or equal to the upper limit of the current command; the execution module is further configured to restrict the initial current command to a value between the upper limit of the current command and the lower limit of the current command in response to the lower limit of the current command being less than the upper limit of the current command, thereby obtaining the target current command.

[0018] In one possible implementation, the device further includes: the processing module, configured to acquire the current inductor current of the boost converter; the processing module is further configured to determine the current difference between the target current command and the current inductor current; the processing module is further configured to perform proportional-integral adjustment calculation on the current difference through the current inner loop to obtain a drive control signal; the processing module is further configured to control the on / off state of the boost converter through the drive control signal, thereby controlling the operation of the boost converter.

[0019] In one possible implementation, the processing module is further configured to perform proportional calculations on the current difference through the inner current loop to compensate for dynamic deviations, and to perform integral calculations to eliminate steady-state current errors, thereby obtaining a current adjustment reference value; the processing module is further configured to generate a carrier signal with a fixed frequency and a periodically linearly varying amplitude according to the internal timing circuit of the boost converter; the processing module is further configured to compare the amplitude of the current adjustment reference value with that of the carrier signal, outputting a high level when the current adjustment reference value is greater than or equal to the amplitude of the carrier signal, and outputting a low level when the current adjustment reference value is less than the amplitude of the carrier signal, thereby obtaining a pulse width modulation signal with an adjustable duty cycle; the processing module is further configured to determine the pulse width modulation signal as the drive control signal.

[0020] Thirdly, embodiments of this application provide an electronic device, including: a memory and a processor;

[0021] The memory stores computer-executed instructions;

[0022] The processor executes computer execution instructions stored in the memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0023] Fourthly, embodiments of this application provide a non-volatile computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible implementations of the first aspect.

[0024] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0025] The photovoltaic bus voltage stabilization method, apparatus, electronic device, and storage medium provided in this application include: acquiring the current bus voltage and the current photovoltaic voltage; calculating the deviation of the current bus voltage from a preset bus voltage using a multi-channel voltage control loop to obtain an upper limit and a lower limit of the current command to match the deviation; determining an appropriate initial current command based on the current photovoltaic voltage; constraining the initial current command according to the upper and lower limits to obtain a target current command; and controlling the boost converter to operate according to the target current command to control the bus voltage. In the event of energy storage unit failure, this solution uses a multi-channel voltage control loop to match the initial current command to the real-time operating conditions of the bus voltage and dynamically constrains the initial current command based on the real-time deviation of the bus voltage, thereby controlling the bus voltage within a safe range and improving power supply stability. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0027] Figure 1 This is a schematic diagram illustrating an application scenario of a photovoltaic bus voltage stabilization method provided in an embodiment of this application.

[0028] Figure 2 A schematic diagram of bus voltage instability provided in an embodiment of this application;

[0029] Figure 3 A schematic flowchart illustrating a photovoltaic bus voltage stabilization method provided in an embodiment of this application;

[0030] Figure 4 A schematic flowchart illustrating another photovoltaic bus voltage stabilization method provided in this application embodiment;

[0031] Figure 5 A schematic diagram of a multi-channel voltage control loop provided in an embodiment of this application;

[0032] Figure 6 This is a schematic diagram illustrating the coordinated operation of the voltage loop and current loop as provided in an embodiment of this application.

[0033] Figure 7 A schematic diagram of the voltage stabilization process provided in an embodiment of this application;

[0034] Figure 8 A schematic diagram illustrating the state changes during the voltage stabilization process provided in an embodiment of this application;

[0035] Figure 9 This is a schematic diagram of the structure of a photovoltaic bus voltage stabilizing device provided in an embodiment of this application;

[0036] Figure 10 This is a schematic diagram of another photovoltaic bus voltage stabilizing device provided in an embodiment of this application;

[0037] Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0038] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0039] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0040] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0041] It should be noted that the phrase "at...time" in the embodiments of this application can refer to the instant at which a certain situation occurs, or to a period of time after the occurrence of a certain situation; the embodiments of this application do not specifically limit this. Furthermore, the display interface provided in the embodiments of this application is merely an example, and the display interface may include more or less content.

[0042] It should be noted that the photovoltaic bus voltage stabilization method, device, electronic equipment and storage medium of this application can be used in the field of photovoltaic technology, or in any field other than photovoltaic. The application field of the photovoltaic bus voltage stabilization method, device, electronic equipment and storage medium of this application is not limited.

[0043] Figure 1This diagram illustrates an application scenario of a photovoltaic bus voltage stabilization method provided in this application. The scenario depicted is as follows: A photovoltaic array serves as the source of electrical energy, converting solar energy into direct current (DC) output. A boost converter boosts and stabilizes the DC output from the photovoltaic array, and the controlled DC power is collected by the DC bus. An inverter converts the DC power from the DC bus into AC power usable by the load for output.

[0044] In practical applications, energy storage units (such as batteries, supercapacitors, etc.) are set up in photovoltaic systems, and the energy storage units are connected to the DC bus.

[0045] In related technologies, energy storage units are used to stabilize the DC bus voltage. These energy storage units are used to directly replenish power to the DC bus when there is a sudden increase in load power or a sharp drop in sunlight, thereby responding to voltage fluctuations and stabilizing the bus voltage.

[0046] However, energy storage units may fail to regulate for various reasons: the battery's state of charge reaches its charge / discharge limits, the battery management system triggers protection actions, the converter malfunctions, or current limiting becomes saturated. Under such failure conditions, dynamic overshoot cannot be effectively suppressed, resulting in poor power supply stability.

[0047] Below, in conjunction with Figure 2 The process of bus voltage instability when only photovoltaic off-grid load is applied is explained.

[0048] Figure 2 This is a schematic diagram of bus voltage instability provided in an embodiment of this application. Figure 2 As shown, in stage 1: initial no-load, the photovoltaic system operates near the open-circuit point on the right half of the power-voltage (PV) curve. The bus voltage stabilizes at the voltage reference value, the voltage outer loop error is zero, the current command is minimal, and the system is in a no-load steady state. The voltage outer loop is the control structure of the boost converter, used to calculate the current command based on the bus voltage reference value and the actual bus voltage.

[0049] Phase 2: Load surge, voltage outer loop response. The sudden load causes the bus voltage to drop instantaneously. After detecting the deviation, the voltage outer loop quickly increases the current command, and the operating point moves to the left along the right half-plane in an attempt to increase the output power to support the bus voltage.

[0050] Stage 3: Current command overshoot, exceeding the maximum power point (MPP). The current command exceeds the maximum power point current under the current illumination, and the operating point crosses the MPP and enters the left half-plane. At this time, the power derivative with respect to voltage is greater than 0, and the photovoltaic output power begins to decrease as the voltage decreases.

[0051] Stage 4: Entering the left half-plane, the characteristic of power decreasing as voltage decreases in the left half-plane triggers positive feedback: voltage decreases, power decreases, bus voltage drops further, current command continues to increase, and the operating point slides to the left at an accelerated pace.

[0052] Stage 5: Positive feedback intensifies, the voltage drop rate accelerates, and the operating point rapidly slides towards the short-circuit point. The outer voltage loop remains saturated, and the system is unable to establish a new equilibrium point.

[0053] Stage 6: The operating point eventually drops to near the short-circuit point, and the photovoltaic output power is almost zero. The boost converter cannot operate normally due to the low input voltage, triggering the undervoltage protection, and the system shuts down.

[0054] The photovoltaic bus voltage stabilization method provided in this application aims to solve the above-mentioned technical problems in related technologies.

[0055] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0056] Figure 3 This is a flowchart illustrating a photovoltaic bus voltage stabilization method provided in an embodiment of this application. The method includes the following steps:

[0057] S301. Collect the current bus voltage and the current photovoltaic voltage.

[0058] In this application, the embodiment is applied to a photovoltaic system, which includes a photovoltaic array, a boost converter, a DC bus, and an inverter.

[0059] In this application, the execution entity is a control circuit, which is used to calculate the target current command in real time and instruct the boost converter to operate based on the target current command. The control circuit can be located inside or outside the boost converter.

[0060] For example, the current bus voltage of the DC bus in the photovoltaic system architecture and the current photovoltaic voltage at the output of the photovoltaic array are collected in real time.

[0061] S302. The deviation of the current bus voltage from the preset bus voltage is calculated by the multi-channel voltage control loop to obtain the upper limit value of the current command and the lower limit value of the current command that are adapted to the deviation.

[0062] For example, each of the multiple voltage control loops corresponds to a different bus voltage deviation operating range. Each loop has independent voltage deviation calculation logic and independent parameter tuning mechanism, and they do not interfere with each other and work in parallel.

[0063] For example, each loop independently calculates the different degrees of deviation of the current bus voltage, such as being too high or too low, and each loop independently calculates and outputs the corresponding current command limit value for its own adapted voltage deviation level. Then, by fusing and matching the calculation results of multiple loops, an upper limit value and a lower limit value of the current command value matching the current bus voltage fluctuation level are dynamically generated.

[0064] For example, the configured multi-channel voltage control loop uses a preset bus voltage as a reference value. It compares the real-time acquired current bus voltage with this reference value to quantify the magnitude deviation of the current bus voltage relative to the preset bus voltage. Then, each voltage control loop synchronously processes the data according to its own control logic and outputs an upper limit and a lower limit of the current command that match the real-time voltage deviation condition. These two limits dynamically and adaptively change with the bus voltage fluctuation state, forming a real-time variable current control constraint boundary.

[0065] Based on the above implementation methods, multi-path voltage control loops are used to achieve multi-condition hierarchical control from an architectural perspective, solving the problem that a single voltage loop cannot accurately control both small and severe fluctuations.

[0066] S303. Determine the appropriate initial current command based on the current photovoltaic voltage.

[0067] For example, based on the current photovoltaic voltage that has been collected, the photovoltaic array's own output voltage-current characteristics are combined with the power generation capacity corresponding to the current lighting environment to calculate an initial current command that is suitable for the current photovoltaic operating state.

[0068] The initial current command conforms to the current output capability of the photovoltaic array and is the original current reference value generated based on the photovoltaic array's own operating conditions.

[0069] S304. Constrain the initial current command according to the upper limit and lower limit of the current command to obtain the target current command.

[0070] For example, the calculated upper and lower limits of the current command are used as constraint thresholds to limit the amplitude and regulate the logic of the initial current command. Limit adaptation is performed according to the current constraint range corresponding to the voltage deviation. Current components that exceed the safe control range are eliminated, and the target current command that meets the bus voltage regulation safety requirements is output.

[0071] S305 controls the boost converter to operate according to the target current command in order to control the bus voltage.

[0072] For example, the target current command is used as the current control value of the boost converter. The operating state of the boost converter is adjusted according to the current control value. By changing the magnitude of the output current injected by the boost converter to the DC bus side, the power supply and demand balance on the DC bus is adjusted.

[0073] By dynamically regulating the current to correct deviations and fluctuations in the bus voltage, the bus voltage is ultimately stabilized within the normal operating range, achieving autonomous voltage regulation control of the photovoltaic bus in the absence of energy storage units or under conditions where energy storage units fail.

[0074] The photovoltaic bus voltage stabilization method provided in this application collects the current bus voltage and the current photovoltaic voltage; calculates the deviation of the current bus voltage from the preset bus voltage through a multi-channel voltage control loop to obtain an upper limit and a lower limit of the current command to adapt to the deviation; determines an appropriate initial current command based on the current photovoltaic voltage; constrains the initial current command according to the upper and lower limits of the current command to obtain a target current command; and controls the boost converter to operate according to the target current command to control the bus voltage. In the event of energy storage unit failure, this scheme, through a multi-channel voltage control loop, matches the initial current command to the real-time operating condition of the bus voltage and dynamically constrains the initial current command based on the real-time deviation of the bus voltage, keeping the bus voltage within a safe range and thus improving power supply stability.

[0075] Based on any of the above embodiments, the following, in conjunction with Figure 4 The detailed process of voltage stabilization for photovoltaic busbars is explained.

[0076] Figure 4 This is a schematic flowchart illustrating another photovoltaic bus voltage stabilization method provided in an embodiment of this application. Figure 4 As shown, the method includes:

[0077] S401. Collect the current bus voltage and the current photovoltaic voltage.

[0078] It should be noted that the execution process of S301 is the same as that of S201, and will not be repeated here.

[0079] S402. Determine the voltage range for each voltage control loop.

[0080] The multi-channel voltage control loop includes: a fast upper limit control loop, a main voltage control loop, and a slow lower limit control loop.

[0081] For example, a dedicated voltage operating range is defined for each voltage control loop, and each voltage control loop corresponds to a different operating range of the bus voltage deviation, with a clear division of the control range.

[0082] S403. Based on the voltage range of each voltage control loop and the preset bus voltage, voltage deviation is allocated to the multiple voltage control loops to obtain multiple voltage deviation thresholds.

[0083] For example, using the preset bus voltage as a reference value, and combining the exclusive voltage range corresponding to each loop, a differentiated voltage deviation allocation is made for each loop, and a voltage deviation threshold is configured for each loop, so that each loop has a judgment benchmark that fits its own control positioning.

[0084] S404. Based on multiple voltage deviation thresholds, the deviation of the current bus voltage from the preset bus voltage is calculated through a multi-channel voltage control loop to obtain the upper limit and lower limit of the current command that are adapted to the deviation.

[0085] For example, each of the multiple loops calculates the deviation of the current bus voltage from the preset bus voltage in real time based on its corresponding voltage range and voltage deviation threshold. After independent calculation according to their respective control logic, they are integrated and output to adapt the upper limit and lower limit of the current command to the current actual operating conditions, so that the current constraint boundary adapts dynamically to the magnitude and degree of bus voltage fluctuation.

[0086] One feasible implementation method is to determine the upper limit and lower limit of the current command using the following methods:

[0087] For example, the fast upper limit control loop has the characteristic of fast response speed and is specifically designed for dynamic operating conditions such as instantaneous fluctuations, sudden drops, or instantaneous rises in bus voltage. Based on its corresponding voltage deviation threshold, it calculates the first current control quantity in real time. This quickly controls the current to prevent it from exceeding the limit and prevents violent oscillations in bus voltage caused by current surges under instantaneous operating conditions.

[0088] For example, the main voltage control loop, as the core main loop of voltage regulation, operates in the normal range of bus voltage deviation and steady-state fluctuation. It performs steady-state closed-loop regulation with the preset bus voltage as the central reference, and undertakes the main task of long-term bus voltage regulation. It works in conjunction with the fast upper limit control loop to jointly determine the second current control quantity and is responsible for voltage balance and power matching under steady-state conditions.

[0089] For example, by determining the minimum value between the first and second current control values, a more conservative and stringent constraint is obtained, namely the upper limit of the current command. This improves the reliability of the voltage regulation.

[0090] For example, the slow lower limit control loop has a smooth response rate. For extreme steady-state conditions such as deep voltage drops on the bus and light load with low current, it performs slow closed-loop calculations based on its own independent voltage deviation threshold, focusing on calculating the lower limit of the current command, which plays a role in current protection and avoids insufficient power support on the bus and continuous voltage drop.

[0091] Based on the above implementation methods, a hierarchical control architecture covering all operating conditions—small fluctuations, moderate deviations, and deep drops in bus voltage—is constructed by differentiating voltage deviation thresholds. This avoids the regulation lag or control failure problems that occur in traditional single voltage loops due to the inability of parameters to simultaneously consider dynamic response, steady-state accuracy, and extreme condition fallback, thereby improving power supply stability.

[0092] S405: Search for the maximum photovoltaic power corresponding to the current photovoltaic voltage through the maximum power tracking voltage loop.

[0093] The multi-channel voltage control loop also includes a maximum power point tracking (MPPT) voltage loop.

[0094] Below, in conjunction with Figure 5 The multi-channel voltage control loop is explained.

[0095] Figure 5 This is a schematic diagram of a multi-channel voltage control loop provided in an embodiment of this application. Figure 5 As shown, PI(s) represents the proportional-integral controller.

[0096] Fast upper limit control loop:

[0097] Input error is

[0098] in, Indicates bus voltage. Indicates the preset bus voltage. This indicates the voltage deviation threshold of the fast upper limit control loop.

[0099] Output: First current control quantity UA.

[0100] Functions: Large proportional gain, fast response, bus voltage drop to When the current exceeds the limit, UA drops rapidly, forcibly suppressing the current limit and preventing current overshoot from exceeding MPP.

[0101] Main voltage control loop:

[0102] Input error:

[0103] in, This indicates the voltage deviation threshold of the main voltage control loop.

[0104] Output: Second current control quantity UB.

[0105] Functions: Maintains bus voltage establishment and recovery, outputs minimum value under no-load conditions, rapidly rises to saturation when load surges, and provides a current upper limit reference.

[0106] Maximum power point tracking voltage loop:

[0107] Input error:

[0108] in, This indicates the photovoltaic voltage reference value, which corresponds to the maximum photovoltaic power. This indicates the current photovoltaic voltage.

[0109] Output: Initial current command .

[0110] Function: Provides current command in steady state, and is limited by other loops in transient state, without interfering with voltage regulation.

[0111] Slow lower limit control loop:

[0112] Input error:

[0113] in, This represents the voltage deviation threshold of the slow lower limit control loop.

[0114] Output: Current command lower limit value LD.

[0115] Functions: Small integral coefficient, slow response; slow rise during deep voltage drops, providing minimum support current and guiding voltage recovery; meets... .

[0116] For example, based on the real-time collected current photovoltaic voltage, the maximum photovoltaic power that the photovoltaic array can output under the current illumination and operating conditions is continuously searched according to the maximum power tracking voltage loop.

[0117] S406. Determine the initial current command based on the current that matches the maximum power of the photovoltaic system.

[0118] For example, after locking in the maximum photovoltaic power, the corresponding operating current under the maximum power condition is matched, and the initial current command is directly determined based on this current.

[0119] With the example of the scenario, the initial current command is completely in line with the power generation limit and output characteristics of the photovoltaic array itself. It is determined only by the maximum power characteristics of the photovoltaic side. The safety constraints of the bus voltage are not taken into account at first. It only provides the original current setting basis for the clamping constraints of the upper and lower limits of the subsequent current command.

[0120] Based on the above implementation method, the maximum power point tracking voltage loop is used in the loop architecture to search for and locate the maximum power point of the photovoltaic array. This can accurately match the actual power generation capacity of the photovoltaic array under different light and temperature conditions, so that the initial current command fits the natural output limit of the photovoltaic array, thereby improving the power supply stability.

[0121] S407. Constrain the initial current command according to the upper limit and lower limit of the current command to obtain the target current command.

[0122] One feasible implementation method is to determine the target current command by: in response to the lower limit of the current command being greater than or equal to the upper limit of the current command, determining the lower limit of the current command as the target current command; in response to the lower limit of the current command being less than the upper limit of the current command, restricting the initial current command to a value between the upper limit of the current command and the lower limit of the current command, thereby obtaining the target current command.

[0123] For example, due to transient operating conditions such as sudden changes in illumination or load surges, the lower limit of the current command may be greater than or equal to the upper limit of the current command, which is an abnormal operating condition of range inversion in multi-loop voltage control. In this case, the lower limit of the current command is determined as the target current command.

[0124] With a scenario example, the core function of the slow lower limit control loop is to provide minimum support current when the voltage drops sharply. Therefore, the current command lower limit is the minimum current threshold to ensure the normal operation of the bus. Thus, setting the current command lower limit as the target current command can forcibly maintain the minimum power support of the bus and avoid photovoltaic system shutdown.

[0125] For example, when the lower limit of the current command is less than the upper limit of the current command, it is within a normal and reasonable range. The initial current command output by the maximum power point tracking loop will be forcibly limited to the range formed by the lower and upper limits of the current command. This avoids the initial current command value being too large or too small, and ultimately outputs a target current command that meets the requirements of bus voltage regulation and instability prevention.

[0126] In this feasible implementation, the upper and lower limit interval discrimination mechanism can automatically identify abnormal operating conditions and achieve voltage protection by fixing the lower limit value of the output, thereby avoiding current runaway caused by control interval disorder and improving power supply stability.

[0127] S408 controls the boost converter to operate according to the target current command in order to control the bus voltage.

[0128] One feasible implementation method is to control the operation of the boost converter by: acquiring the current inductor current of the boost converter; determining the current difference between the target current command and the current inductor current; performing proportional-integral adjustment calculation on the current difference through the current inner loop to obtain the drive control signal; and controlling the on / off state of the boost converter through the drive control signal, thereby controlling the operation of the boost converter.

[0129] For example, in a boost converter topology, the inductor is the core energy storage element, and the inductor current is the instantaneous, real-time current flowing through the inductor. The inductor current directly determines the energy transfer rate, output power, and the balance between the switching transistor stress and the power on the bus side of the boost converter; it is a physical quantity reflecting the actual operating conditions of the converter. Using the inductor current as a feedback quantity, instantaneous current suppression and steady-state error-free regulation can be achieved, enabling the boost converter to operate smoothly and controllably.

[0130] Optionally, the current inductor current can be acquired by means of sampling resistors, Hall current sensors, etc.

[0131] For example, the current difference between the target current command and the current inductor current is calculated to characterize the direction and magnitude of the deviation of the actual operating condition from the desired operating condition.

[0132] For example, proportional-integral regulation is performed through the inner current loop to process the current difference numerically: the proportional loop outputs the corresponding adjustment increment according to the instantaneous magnitude of the current difference, and the integral loop performs long-term cumulative compensation on the current difference. The two are superimposed to obtain a continuously variable analog control quantity, i.e., the drive control signal.

[0133] The boost converter is controlled to switch on and off according to the switching sequence of the drive control signal, thereby controlling the boost converter to perform voltage regulation.

[0134] In this feasible implementation, the inductor current directly corresponds to the converter's energy transmission rate and the circuit load condition. Using it as a feedback quantity, circuit abnormalities can be detected in a timely manner, thereby accurately regulating the voltage and improving power supply stability.

[0135] One feasible implementation method involves generating the drive control signal as follows: Compensating for dynamic deviations by performing proportional calculations on the current difference using an inner current loop, and eliminating steady-state current errors through integral calculations to obtain a current regulation reference value; generating a carrier signal with a fixed frequency and linearly varying amplitude according to the period based on the internal timing circuit of the boost converter; comparing the amplitude of the current regulation reference value with that of the carrier signal, outputting a high level when the current regulation reference value is greater than or equal to the amplitude of the carrier signal, and outputting a low level when the current regulation reference value is less than the amplitude of the carrier signal, thus obtaining a pulse width modulation signal with an adjustable duty cycle; and determining the pulse width modulation signal as the drive control signal.

[0136] Below, in conjunction with Figure 6 The working relationship between the voltage loop and the current loop is explained.

[0137] Figure 6 This is a schematic diagram illustrating the coordinated operation of the voltage loop and current loop as provided in an embodiment of this application. Figure 6 As shown, the target current command output by the current loop to the voltage loop is compared with the current inductor current. Calculate the current difference. Perform proportional-integral (PI) regulation and limiting on the current difference to obtain the drive control signal. Limit the current command using a limiter, which includes an upper and lower current limit, to ensure that the limited current command is within a safe range.

[0138] For example, the inner current loop simultaneously performs proportional and integral calculations on the acquired current difference to obtain the current adjustment reference value, which represents the control quantity corresponding to the current amplitude to be adjusted.

[0139] For example, a carrier signal (e.g., a sawtooth wave or a triangular wave) with a fixed frequency and a periodically linearly varying amplitude is generated based on the internal timing circuit of the boost converter.

[0140] The fixed frequency ensures stable operating timing of the boost converter's switching devices, preventing current oscillations caused by frequency fluctuations. The linearly varying amplitude can be precisely compared with the current adjustment reference value, enabling continuous adjustment of the duty cycle.

[0141] For example, the current regulation reference value is compared with the carrier signal in real time. When the current regulation reference value is greater than or equal to the current amplitude of the carrier signal, a high level is output. When the current regulation reference value is less than the current amplitude of the carrier signal, a low level is output. Through continuous amplitude comparison, a pulse width modulation (PWM) signal with a fixed frequency and a duty cycle that dynamically changes with the current regulation reference value is generated.

[0142] In pulse width modulation signals, the change in duty cycle directly corresponds to the change in current adjustment reference value. That is, the greater the deviation, the greater the duty cycle adjustment range, thus realizing the mapping between the adjustment amount and the pulse signal.

[0143] With the help of scenario examples, the pulse width modulation signal has the characteristics of fixed frequency and adjustable duty cycle, which can be directly adapted to the driving requirements of the power switching devices of the boost converter. Therefore, it is directly determined as the driving control signal to control the on and off of the switching devices.

[0144] In this feasible implementation, a pulse width modulation signal is generated by comparing the amplitude of the reference value with that of the carrier signal, so as to achieve continuous adjustment of the duty cycle. The duty cycle is accurately mapped with the current deviation and the adjustment reference value, so that the drive control signal can follow the changes in current deviation in real time, resulting in higher control accuracy and thus improving power supply stability.

[0145] Below, in conjunction with Figure 7 The voltage regulation process of the embodiments of this application will be described.

[0146] Figure 7 This is a schematic diagram of the voltage regulation process provided in an embodiment of this application. Figure 7 As shown, in stage 1: the bus voltage stabilizes at the voltage reference value, loop B (main voltage control loop) outputs a minimum value UB0, and loop A (fast upper limit control loop) saturates at 1. Therefore, the upper limit of the current command = UB0, and the target current command = UB0. Loop C (maximum power point tracking loop) outputs an initial current command at its maximum value (MPP point), but it is truncated due to the upper limit limitation. Loop D (slow lower limit control loop) outputs 0. The photovoltaic operating point is located in the right half of the PV curve, close to the open circuit point, at which point the power is extremely low.

[0147] Phase 2 (Load Surge): Load is applied, the bus voltage drops rapidly, triggering the left-side protection loop (which determines the maximum current). Loop B error increases, UB rises rapidly, the current command upper limit rises accordingly, the target current command increases to a large value, and the photovoltaic operating point shifts to the left, even briefly entering the left half-plane. Without loop A intervention, the operating point would continue to shift to the left, leading to failure. However, at this point, the bus voltage has already dropped to... Loop A will now begin to respond.

[0148] Stage 3 (Loop A Backwards): The output UA of Loop A drops rapidly, causing a sharp decrease in the upper limit of the current command. The target current command then decreases accordingly, pulling the operating point back to the right half-plane. This process is completed in milliseconds, effectively preventing overshoot from entering the deep left half-plane.

[0149] Stage 4 (Loop D Takeover): Bus voltage drops below [a certain value] after a deep dip. The lower limit of the current command LD output by loop D slowly rises. When LD exceeds the upper limit of the current command, according to the lower limit priority rule, the target current command = LD, the operating point slowly shifts to the right with LD, and the bus voltage gradually rises back to its previous value. nearby.

[0150] Stage 5: As the bus voltage stabilizes at Loop A has returned to saturation (UA=1), the upper limit of the current command is UB=1, and the initial current command slowly decreases from its initial maximum value. When the initial current command drops below LD, the target current command is still determined by LD; subsequently, the initial current command increases, and when the current output by loop C, IrefC, is greater than LD, the initial current command equals IrefC, and the operating point continues to shift to the right.

[0151] Stage 6 (Steady-state recovery): Bus voltage recovers to The output of loop B drops back to UB0, the upper limit of the current command equals UB0, the target current command is limited to a minimum value, and the photovoltaic system enters a light-load steady state. This operating point is located in the right half-plane, and the power corresponds to the actual load demand.

[0152] Below, in conjunction with Figure 8 The state changes during the voltage stabilization process in the embodiments of this application will be described.

[0153] Figure 8 This is a schematic diagram illustrating the state changes during the voltage stabilization process provided in an embodiment of this application. For example... Figure 8 As shown, Stage 1: No-load steady state (t=0~2), the bus voltage stabilizes at the preset bus voltage. Under no-load conditions, the bus voltage is in a relatively high safe range.

[0154] Current value:

[0155] Loop A (UA): Constrained by the upper limit of the current command, it is always 1.

[0156] Loop B (UB): Constrained by the upper limit of the current command, it is always 1.

[0157] Loop D (LD, lower current limit): No current demand under no-load conditions, always 0.

[0158] Loop C (Initial Current Command): Slowly decreasing (indicating that the light or photovoltaic voltage is changing slowly, but the current demand is extremely low at this time).

[0159] The target current command is maintained at a very low level, and the system is in an idle standby state.

[0160] Phase 2: Instantaneous load (t=2~3), the bus voltage suddenly drops sharply at time t=2 due to the sudden connection of the load, from 1.05 to approximately 0.87 (below 0.05). (Range), entering a deep undervoltage state.

[0161] Current value:

[0162] Loop A: The voltage drops rapidly from 1, entering the voltage drop protection mode and starting to output the upper limit constraint value of the current.

[0163] Loop B: Remains at 1, and the upper limit constraint has not yet been triggered.

[0164] Loop D: Rapidly rises from 0 to obtain the lower limit of the current constraint, that is, in order to support the bus voltage, the photovoltaic system is required to ensure that the photovoltaic output current is not lower than the lower limit of the current constraint.

[0165] The target current command is pulled to a higher level, following the lower limit requirement of loop D, forcibly increasing the photovoltaic output current to cope with voltage drops.

[0166] Phase 3: Loop A bottoms out and connects to Loop D (t=3~5). After the bus voltage bottoms out, it begins to slowly rise, from the lowest point towards... Within the range, the voltage value approximately 0.97 recovers.

[0167] Current value:

[0168] Loop A: If the current drops to 0 and remains there for a period of time, it indicates that the left-side protection loop (overvoltage / drop protection) is in a deep protection state and the current limit is forcibly lowered.

[0169] Loop D: Continuously rising, becoming the dominant lower current limit constraint.

[0170] Loop C: Still slowly declining.

[0171] The target current command follows the lower limit of the current command in loop D, which is slowly raised, forcing the photovoltaic output current to increase and driving the bus voltage to rise.

[0172] Phase 4: Temporary Stability (t=5~8), the bus voltage recovers to The system remains stable within the specified range and enters a temporary stable phase.

[0173] Current value:

[0174] Loop A: Returning to 1 indicates that the voltage has moved out of the deep voltage drop range, the protection mode has exited, and the current limit has returned to normal.

[0175] Loop B: Maintains 1, upper limit constraint not triggered.

[0176] Loop D: stabilizes at 0.7, becoming the lower limit of the current command at this time.

[0177] Loop C: After decreasing to 0.7, it tends to stabilize.

[0178] The target current command is the lower limit of loop D, which satisfies the bus requirements without exceeding the current capacity of loop C.

[0179] Stage 5: (t=8~10) At time t=8, the power of loop C increases, the photovoltaic output current increases, and the bus voltage begins to rise, initially reaching around 1.07 (brief overvoltage), then falling back and stabilizing at... The nearby steady-state value.

[0180] Current value:

[0181] Loop C: Starting from 0.7, it increases, the photovoltaic output capacity is enhanced, and the current limit is raised.

[0182] Loop B: Brief drop, triggering the right loop (overvoltage protection) current upper limit constraint.

[0183] The target current command increases following the initial current command, but is constrained by the upper limit of loop B to prevent excessive current from causing overvoltage on the bus. It eventually stabilizes at around 0.8, and the photovoltaic system enters a new steady state.

[0184] Figure 9 This is a schematic diagram of a photovoltaic bus voltage stabilization device provided in an embodiment of this application. Figure 9 As shown, the photovoltaic bus voltage stabilization device 90 may include: a data acquisition module 91, a calculation module 92, a determination module 93, an execution module 94, and a control module 95.

[0185] The acquisition module 91 is used to acquire the current bus voltage and the current photovoltaic voltage.

[0186] The calculation module 92 is used to calculate the deviation of the current bus voltage from the preset bus voltage through the multi-channel voltage control loop, and obtain the upper limit value of the current command and the lower limit value of the current command that are adapted to the deviation.

[0187] The determination module 93 is used to determine the appropriate initial current command based on the current photovoltaic voltage.

[0188] The execution module 94 is used to constrain the initial current command according to the upper limit value and the lower limit value of the current command to obtain the target current command.

[0189] The control module 95 is used to control the operation of the boost converter according to the target current command, so as to control the bus voltage.

[0190] Optionally, the acquisition module 91 can execute... Figure 3 S301 in the embodiment.

[0191] Optionally, the calculation module 92 can perform... Figure 3 S302 in the embodiment.

[0192] Optionally, module 93 can be executed. Figure 3 S303 in the embodiment.

[0193] Optionally, execution module 94 can execute Figure 3 S304 in the embodiment.

[0194] Optionally, control module 95 can execute Figure 3 S305 in the embodiment.

[0195] It should be noted that the photovoltaic bus voltage stabilizing device shown in the embodiments of this application can execute the technical solution shown in the above method embodiments, and its implementation principle and beneficial effects are similar, so they will not be described again here.

[0196] In one possible implementation, the computing module 92 is specifically used for:

[0197] Determine the voltage range for each voltage control loop.

[0198] Based on the voltage range of each voltage control loop and the preset bus voltage, voltage deviation is allocated to each of the multiple voltage control loops to obtain multiple voltage deviation thresholds.

[0199] Based on multiple voltage deviation thresholds, the deviation of the current bus voltage from the preset bus voltage is calculated through multiple voltage control loops to obtain the upper limit and lower limit of the current command that are adapted to the deviation.

[0200] In one possible implementation, the computing module 92 is specifically used for:

[0201] The first current control quantity and the second current control quantity are obtained by calculating the deviation between the corresponding voltage deviation threshold and the current bus voltage through the fast upper limit control loop and the main voltage control loop, respectively.

[0202] The minimum value between the first current control value and the second current control value is determined as the upper limit value of the current command.

[0203] The current command lower limit value is obtained by calculating the deviation between the corresponding voltage deviation threshold and the current bus voltage through the slow lower limit control loop.

[0204] In one possible implementation, the determining module 93 is specifically used for:

[0205] The maximum power of the photovoltaic system is searched for at the current photovoltaic voltage using the maximum power tracking voltage loop.

[0206] The initial current command is determined based on the current that matches the maximum power of the photovoltaic system.

[0207] In one possible implementation, execution module 94 is specifically used for:

[0208] If the lower limit of the current command is greater than or equal to the upper limit of the current command, then the lower limit of the current command is determined as the target current command.

[0209] If the lower limit of the current command is less than the upper limit of the current command, the initial current command is restricted to a value between the upper and lower limits of the current command to obtain the target current command.

[0210] Figure 10 This is a schematic diagram of another photovoltaic bus voltage stabilizing device provided in an embodiment of this application. Figure 9 Based on the illustrated embodiments, as Figure 10 As shown, the photovoltaic bus voltage stabilizing device 90 also includes a processing module 96.

[0211] Processing module 96 is used for:

[0212] Collect the current inductor current of the boost converter.

[0213] Determine the current difference between the target current command and the current inductor current.

[0214] The drive control signal is obtained by performing proportional-integral adjustment calculations on the current difference through the inner current loop.

[0215] By driving the control signal, the on / off state of the boost converter is controlled, thereby controlling the operation of the boost converter.

[0216] In one possible implementation, the processing module 96 is specifically used for:

[0217] The dynamic deviation is compensated by proportional calculation of the current difference through the inner current loop, and the steady-state current error is eliminated by integral calculation to obtain the current regulation reference value.

[0218] Based on the internal timing circuit of the boost converter, a carrier signal with a fixed frequency and a linearly varying amplitude according to the period is generated.

[0219] The amplitude of the current adjustment reference value is compared with that of the carrier signal. A high level is output when the current adjustment reference value is greater than or equal to the amplitude of the carrier signal, and a low level is output when the current adjustment reference value is less than the amplitude of the carrier signal, thus obtaining a pulse width modulation signal with adjustable duty cycle.

[0220] The pulse width modulation signal is determined as the drive control signal.

[0221] Figure 11 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application, such as... Figure 11 As shown, the electronic device includes:

[0222] The electronic device includes a processor 291 and a memory 292; it may also include a communication interface 293 and a bus 294. The processor 291, memory 292, and communication interface 293 can communicate with each other via the bus 294. The communication interface 293 can be used for information transmission. The processor 291 can invoke logical instructions stored in the memory 292 to execute the methods of the above embodiments.

[0223] Furthermore, the logic instructions in the aforementioned memory 292 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium.

[0224] The memory 292, as a non-volatile computer-readable storage medium, can be used to store software programs and computer-executable programs, such as program instructions / modules corresponding to the methods in the embodiments of this application. The processor 291 executes functional applications and data processing by running the software programs, instructions, and modules stored in the memory 292, that is, it implements the methods in the above-described method embodiments.

[0225] The memory 292 may include a program storage area and a data storage area. The program storage area may store the operating system and application programs required for at least one function; the data storage area may store data created based on the use of the terminal device. Furthermore, the memory 292 may include high-speed random access memory and may also include non-volatile memory.

[0226] This application provides a non-volatile computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the method as described in the foregoing embodiments.

[0227] This application provides a computer program product, including a computer program that, when executed by a processor, implements the method as described in the foregoing embodiments.

[0228] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0229] It should be further noted that although the steps in the flowchart are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps; they can be executed in other orders. Moreover, at least some steps in the flowchart may include multiple sub-steps or multiple stages, which do not necessarily complete at the same time but can be executed at different times. The execution order of these sub-steps or stages is also not necessarily sequential but can be alternated or carried out in turn with other steps or at least some of the sub-steps or stages of other steps.

[0230] It should be understood that the above-described device embodiments are merely illustrative, and the device of this application can also be implemented in other ways. For example, the division of units / modules in the above embodiments is only a logical functional division, and there may be other division methods in actual implementation. For example, multiple units, modules, or components may be combined, or integrated into another system, or some features may be ignored or not executed.

[0231] Furthermore, unless otherwise specified, the functional units / modules in the various embodiments of this application can be integrated into one unit / module, or each unit / module can exist physically separately, or two or more units / modules can be integrated together. The integrated units / modules described above can be implemented in hardware or as software program modules.

[0232] When integrated units / modules are implemented in hardware, the hardware can be digital circuits, analog circuits, etc. The physical implementation of the hardware structure includes, but is not limited to, transistors, memristors, etc. The processor can be any suitable hardware processor, such as CPU, GPU, FPGA, DSP, and ASIC. The storage unit can be any suitable magnetic or magneto-optical storage medium, such as Resistive Random Access Memory (RRAM), Dynamic Random Access Memory (DRAM), Static Random Access Memory (SRAM), Enhanced Dynamic Random Access Memory (EDRAM), High-Bandwidth Memory (HBM), Hybrid Memory Cube (HMC), etc.

[0233] If the integrated unit / module is implemented as a software program module and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to related technologies, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0234] In the above embodiments, the descriptions of each embodiment have their own emphasis. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0235] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the claims.

[0236] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A photovoltaic bus voltage stabilization method, characterized in that, include: Collect the current bus voltage and the current photovoltaic voltage; The deviation of the current bus voltage from the preset bus voltage is calculated by the multi-channel voltage control loop to obtain the upper limit value of the current command and the lower limit value of the current command that are adapted to the deviation. Based on the current photovoltaic voltage, determine the appropriate initial current command; The initial current command is constrained based on the upper limit and lower limit of the current command to obtain the target current command; The boost converter is controlled to operate according to the target current command in order to control the bus voltage.

2. The method according to claim 1, characterized in that, The multi-channel voltage control loop includes: a fast upper limit control loop, a main voltage control loop, and a slow lower limit control loop; the multi-channel voltage control loop calculates the deviation of the current bus voltage from the preset bus voltage to obtain an upper limit and a lower limit of the current command adapted to the deviation, including: Determine the voltage range for each of the voltage control loops; Based on the voltage range of each voltage control loop and the preset bus voltage, voltage deviation is allocated to each of the multiple voltage control loops to obtain multiple voltage deviation thresholds; Based on the multiple voltage deviation thresholds, the deviation of the current bus voltage from the preset bus voltage is calculated by a multi-channel voltage control loop to obtain the upper limit and lower limit of the current command that are adapted to the deviation.

3. The method according to claim 2, characterized in that, Based on the multiple voltage deviation thresholds, the deviation of the current bus voltage from the preset bus voltage is calculated using a multi-channel voltage control loop to obtain an upper limit and a lower limit for the current command that adapts to the deviation, including: The first current control quantity and the second current control quantity are obtained by calculating the deviation between the corresponding voltage deviation threshold and the current bus voltage through the fast upper limit control loop and the main voltage control loop, respectively. The minimum value between the first current control value and the second current control value is determined as the upper limit value of the current command; The current command lower limit value is obtained by calculating the degree of deviation between the corresponding voltage deviation threshold and the current bus voltage through the slow lower limit control loop.

4. The method according to claim 1, characterized in that, The multi-channel voltage control loop includes a maximum power point tracking (MPPT) voltage loop; based on the current photovoltaic voltage, an appropriate initial current command is determined, including: The maximum photovoltaic power corresponding to the current photovoltaic voltage is searched through the maximum power tracking voltage loop; The initial current command is determined based on the current that matches the maximum power of the photovoltaic system.

5. The method according to claim 1, characterized in that, The initial current command is constrained based on the upper and lower limits of the current command to obtain the target current command, including: In response to the current command lower limit being greater than or equal to the current command upper limit, the current command lower limit is determined as the target current command; In response to the lower limit of the current command being less than the upper limit of the current command, the initial current command is restricted to a value between the upper limit of the current command and the lower limit of the current command to obtain the target current command.

6. The method according to any one of claims 1-5, characterized in that, Controlling the boost converter to operate according to the target current command includes: Collect the current inductor current of the boost converter; Determine the current difference between the target current command and the current inductor current; The drive control signal is obtained by performing proportional-integral adjustment calculation on the current difference through the inner current loop; The boost converter is switched on and off by the drive control signal, thereby controlling the operation of the boost converter.

7. The method according to claim 6, characterized in that, The drive control signal is obtained by performing proportional-integral adjustment calculation on the current difference through the inner current loop, including: The current difference is proportionally calculated to compensate for dynamic deviation by the inner current loop, and integral calculation is performed to eliminate steady-state current error, so as to obtain the current regulation reference value. The internal timing circuit of the boost converter generates a carrier signal with a fixed frequency and a linearly varying amplitude according to the period. The current adjustment reference value is compared with the amplitude of the carrier signal. A high level is output when the current adjustment reference value is greater than or equal to the amplitude of the carrier signal, and a low level is output when the current adjustment reference value is less than the amplitude of the carrier signal, thus obtaining a pulse width modulation signal with adjustable duty cycle. The pulse width modulation signal is determined as the drive control signal.

8. A photovoltaic bus voltage stabilizing device, characterized in that, include: The data acquisition module is used to acquire the current bus voltage and the current photovoltaic voltage. The calculation module is used to calculate the deviation of the current bus voltage from the preset bus voltage through a multi-channel voltage control loop, and obtain the upper limit value of the current command and the lower limit value of the current command that are adapted to the deviation. The determination module is used to determine the appropriate initial current command based on the current photovoltaic voltage; The execution module is used to constrain the initial current command according to the upper limit value and the lower limit value of the current command to obtain the target current command; The control module is used to control the operation of the boost converter according to the target current command, so as to control the bus voltage.

9. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in any one of claims 1-7.

10. A non-volatile computer-readable storage medium, characterized in that, The non-volatile computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-7.

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