Off-grid Inverter's Load-carrying Current Limiting Control Method, Electronic Device and Storage Medium

Abstract

The present invention discloses a load-carrying current limiting control method, an electronic device and a storage medium for an off-grid inverter. Among them, the load-carrying current limiting control method includes: when the off-grid inverter is in a load-carrying operation state, continuously obtaining the real-time inverter current of the off-grid inverter and monitoring the real-time load-carrying operation status of the off-grid inverter; according to the magnitude relationship between the real-time inverter current and the first preset current limiting threshold and the second preset current limiting threshold, and combining the real-time load-carrying operation status of the off-grid inverter, performing current limiting control on the off-grid inverter. In the present invention, not only can the special working condition requirements of the off-grid inverter for suddenly adding inductive loads, suddenly adding capacitive loads and not limiting current under rated double load be met, especially when protecting in extreme working conditions, current limiting control of the off-grid inverter can be realized, effectively limiting the magnitude of the peak current of the inverter circuit, thereby greatly reducing the device protection selection requirements and achieving the purpose of reducing the device protection cost of the off-grid inverter.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronic control, and in particular to a load-carrying current limiting control method, an electronic device, and a computer-readable storage medium for an off-grid inverter. Background Art

[0002] At present, the current limiting point of the off-grid inverters on the market is set singly. In order to meet the requirement of not limiting the current under the rated double load, the value of this current limiting point is usually set relatively large, which results in an excessive instantaneous impact current when the inverter system faces a sudden capacitive load or a sudden inductive load. Therefore, when designing the whole system, devices with a higher peak current resistance need to be selected, leading to an increase in protection cost. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to some extent. For this purpose, the present invention provides a load-carrying current limiting control method, an electronic device, and a storage medium for an off-grid inverter, which can reduce the device protection cost of the off-grid inverter.

[0004] In a first aspect, an embodiment of the present invention provides a load-carrying current limiting control method for an off-grid inverter, including the following steps:

[0005] Step S1: When the off-grid inverter is in a load-carrying operation state, continuously obtain the real-time inverter current of the off-grid inverter, and monitor the real-time load-carrying operation status of the off-grid inverter;

[0006] Step S2: According to the magnitude relationship between the real-time inverter current and a first preset current limiting threshold and a second preset current limiting threshold, and in combination with the real-time load-carrying operation status of the off-grid inverter, perform current limiting control on the off-grid inverter, where the first preset current limiting threshold is less than the second preset current limiting threshold.

[0007] Optionally, in an embodiment of the present invention, the step S2 includes the following steps:

[0008] Step S21: When the real-time inverter current is greater than or equal to the first preset current limiting threshold and less than the second preset current limiting threshold, determine the current load-carrying power frequency period of the off-grid inverter according to the real-time load-carrying operation status of the off-grid inverter;

[0009] Step S22: Perform current limiting control on the off-grid inverter according to the current load-carrying power frequency period of the off-grid inverter.

[0010] Optionally, in an embodiment of the present invention, the step S22 includes the following steps:

[0011] Step S221: When the current on - load power frequency period of the off - grid inverter is less than or equal to the maximum short - time current - limiting power frequency period, use the first preset current - limiting threshold as the first current - limiting point to perform per - cycle protection on the off - grid inverter;

[0012] Or,

[0013] Step S222: When the current on - load power frequency period of the off - grid inverter is greater than the maximum short - time current - limiting power frequency period, maintain the current operating state of the off - grid inverter.

[0014] Optionally, in an embodiment of the present invention, step S2 includes the following steps:

[0015] Step S23: When the real - time inverter current is greater than or equal to the second preset current - limiting threshold, use the second preset current - limiting threshold as the second current - limiting point to perform single - trigger protection on the off - grid inverter until the next on - load power frequency period of the off - grid inverter is reached, where the next on - load power frequency period of the off - grid inverter is determined according to the on - load real - time operating conditions of the off - grid inverter;

[0016] Step S24: In the next on - load power frequency period of the off - grid inverter, soft - start the off - grid inverter, continuously obtain the real - time inverter current of the off - grid inverter, and return to execute step S23;

[0017] Step S25: Real - time monitor the number of cycles of executing step S23 and step S24, and perform current - limiting control on the off - grid inverter according to the magnitude relationship between the number of cycles and the preset cycle protection number threshold.

[0018] Optionally, in an embodiment of the present invention, the step in step S25 of performing current - limiting control on the off - grid inverter according to the magnitude relationship between the number of cycles and the preset cycle protection number threshold includes the following steps:

[0019] Step S251: When the number of cycles is less than or equal to the preset cycle protection number threshold, maintain the execution of step S23 and step S24;

[0020] Or,

[0021] Step S252: When the number of cycles is greater than the preset cycle protection number threshold, turn off the off - grid inverter.

[0022] Optionally, in an embodiment of the present invention, step S2 includes the following steps:

[0023] Step S26: When the real - time inverter current is less than the first preset current - limiting threshold, maintain the current operating state of the off - grid inverter.

[0024] Optionally, in an embodiment of the present invention, the first preset current limiting threshold is the peak inverter current of the off-grid inverter under rated load, and the second preset current limiting threshold is twice the first preset current limiting threshold.

[0025] Second, an embodiment of the present invention provides an electronic device, including:

[0026] At least one processor;

[0027] At least one memory for storing at least one program;

[0028] When at least one of the at least one program is executed by at least one of the at least one processor, the on-load current limiting control method of the off-grid inverter as described in the first aspect is implemented.

[0029] Third, an embodiment of the present invention provides a computer-readable storage medium, in which a program executable by a processor is stored, and when the program executable by the processor is executed by the processor, it is used to implement the on-load current limiting control method of the off-grid inverter as described in the first aspect.

[0030] The on-load current limiting control method, electronic device, and computer-readable storage medium of the off-grid inverter proposed by the present invention, in the case where the off-grid inverter is in an on-load operation state, obtain the real-time inverter current of the off-grid inverter, compare the real-time inverter current with two preset current limiting points of the inverter circuit, so as to judge the magnitude relationship between the real-time inverter current and the first preset current limiting threshold and the second preset current limiting threshold, and also monitor the real-time on-load operation status of the off-grid inverter. Compared with the related prior art, it can not only meet the special working condition requirements of the off-grid inverter for suddenly adding inductive loads, suddenly adding capacitive loads, and not limiting current under rated double load, especially when protecting in extreme working conditions, combining the above relationship parameters and the real-time on-load operation status of the off-grid inverter, realizing the current limiting control of the off-grid inverter, effectively limiting the magnitude of the peak current of the inverter circuit, thereby greatly reducing the device protection selection requirements and achieving the purpose of reducing the device protection cost of the off-grid inverter. Description of the Drawings

[0031] Figure 1 is a flowchart of the on-load current limiting control method of the off-grid inverter provided by an embodiment of the present invention;

[0032] Figure 2 is a schematic diagram of the control structure for executing the on-load current limiting control method of the off-grid inverter provided by an embodiment of the present invention;

[0033] Figure 3 is Figure 1 a flowchart of step S2 in

[0034] Figure 4Yes Figure 1 Another flowchart of step S2 in

[0035] Figure 5 Yes Figure 1 Another flowchart of step S2 in

[0036] Figure 6 Schematic diagram of the execution process of the load current limiting control method for an off-grid inverter provided by an embodiment of the present invention;

[0037] Figure 7 Schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. Detailed implementation manners

[0038] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

[0039] It should be noted that although functional module division is performed in the device schematic diagram and the logical sequence is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from the module division in the device or the sequence in the flowchart.

[0040] Figure 1 Flowchart of the load current limiting control method for an off-grid inverter provided by an embodiment of the present invention, as Figure 1 shown, the load current limiting control method for the off-grid inverter may but is not limited to include steps S1 to S2.

[0041] Step S1: When the off-grid inverter is in a load operation state, continuously obtain the real-time inverter current of the off-grid inverter and monitor the real-time load operation status of the off-grid inverter;

[0042] Step S2: According to the magnitude relationship between the real-time inverter current and the first preset current limiting threshold and the second preset current limiting threshold, and in combination with the real-time load operation status of the off-grid inverter, perform current limiting control on the off-grid inverter, where the first preset current limiting threshold is less than the second preset current limiting threshold.

[0043] In this step, when the off-grid inverter is in the load operation state, the real-time inverter current of the off-grid inverter is obtained to compare the real-time inverter current with two preset current limiting points of the inverter circuit, so as to judge the magnitude relationship between the real-time inverter current and the first preset current limiting threshold and the second preset current limiting threshold. In addition, the real-time load operation condition of the off-grid inverter is monitored. Compared with the related prior art, it can not only meet the special working condition requirements of the off-grid inverter for suddenly adding inductive loads, suddenly adding capacitive loads and not limiting current under rated double load. Especially when protecting under extreme working conditions, combining the above relationship parameters and the real-time load operation condition of the off-grid inverter, the current limiting control of the off-grid inverter is realized, effectively limiting the magnitude of the peak current of the inverter circuit, thus greatly reducing the device protection selection requirements and achieving the purpose of reducing the device protection cost of the off-grid inverter. Among them, the above-mentioned "extreme working conditions" can include, but are not limited to, suddenly adding inductive loads, suddenly adding capacitive loads, suddenly adding impact loads, and short circuit on the inverter output side, etc. Moreover, considering that in the related prior art, under extreme working conditions, when the actual current value drops to the only current limiting point, the inverter continues to generate waves in the next switching cycle, and the large impact current persists, resulting in a rapid increase in the device junction temperature, thus reducing the reliability of the device at high temperatures. In contrast, since the present application effectively limits the magnitude of the peak current of the inverter circuit, the above situation can be avoided, and the reliability of the device at high temperatures is improved.

[0044] It should be noted that the types and specifications of the off-grid inverter can be various and are not limited here. To better illustrate the working principle of the embodiments of the present invention, the following gives a control structure related to the off-grid inverter as an example but not a limitation. This control structure can be used, but is not limited to, implementing the load current limiting control method of the embodiments of the present invention.

[0045] As Figure 2 shown, this control structure can include, but is not limited to, an inverter power inductor L_inv, a current sensor I_sam, an inverter filter capacitor C1, a sampling circuit, a driving circuit, and a control chip (which can be, but is not limited to, an MCU, etc.). The specific connection relationship can be referred to Figure 2 and will not be elaborated here. Among them, the driving circuit is used to provide startup power for the inverter circuit of the off-grid inverter. The output side V_out of the inverter circuit is loaded. The current sensor I_sam is connected to one side of the inverter circuit to collect the real-time inverter current of the off-grid inverter and report the collected real-time inverter current to the sampling circuit. Then the sampling circuit reports the real-time inverter current to the control chip, so as to realize the current limiting control of the off-grid inverter through the control chip, the driving circuit, etc.; according to the experimental results, based on this control structure to execute the load current limiting control method of the embodiments of the present invention, the peak current of the inverter circuit can be reduced to 0.6 - 0.8 times of the original, that is, effectively limiting the magnitude of the peak current of the inverter circuit.

[0046] In one embodiment, the specific values of the first preset current limiting threshold and the second preset current limiting threshold can be set accordingly according to the actual application scenario, which is not limited here. For example, but not limited to, the first preset current limiting threshold is the inverter peak current of the off-grid inverter under the rated load, and the second preset current limiting threshold is twice the first preset current limiting threshold, that is

[0047] ;

[0048] ;

[0049] wherein is the first preset current limiting threshold, is the second preset current limiting threshold, is the rated output power of the inverter circuit, is the effective value of the AC output voltage of the inverter circuit, is an error coefficient that can be adjusted according to the actual application scenario, with a value of about 1, for example, a value of 1.1.

[0050] Such as Figure 3 shown, in one embodiment of the present invention, step S2 may include, but not limited to, steps S21 to S22.

[0051] Step S21, when the real-time inverter current is greater than or equal to the first preset current limiting threshold and less than the second preset current limiting threshold, determine the current load power frequency period of the off-grid inverter according to the on-load real-time operating condition of the off-grid inverter;

[0052] Step S22, perform current limiting control on the off-grid inverter according to the current load power frequency period of the off-grid inverter.

[0053] In this step, when the off-grid inverter is turned on and connected to the load, if it is determined that the real-time inverter current is greater than or equal to the first preset current limiting threshold and less than the second preset current limiting threshold, then further combine the on-load real-time operating condition of the off-grid inverter to determine the current load power frequency period of the off-grid inverter, so as to realize effective current limiting control for the off-grid inverter according to the current load power frequency period of the off-grid inverter, so as to limit the magnitude of the peak current of the off-grid inverter and reduce the device protection cost of the off-grid inverter.

[0054] In one embodiment of the present invention, step S22 may include, but not limited to, steps S221 or S222.

[0055] Step S221: When the current on - grid inverter's loaded power frequency period is less than or equal to the maximum short - time current - limiting power frequency period, use the first preset current - limiting threshold as the first current - limiting point to perform cycle - by - cycle protection on the on - grid inverter. Among them, cycle - by - cycle protection is CBC protection, which is characterized in that once triggered, it will set the PWM output level to a preset level (such as high level, low level, high - impedance state or unchanged). However, whenever the CNT of PWM is 0, it will re - detect whether the input of the TZ pin is still triggered. If it is no longer triggered, the protection state will be cleared and the PWM output will be restored. If it is triggered again, the protection state will continue to be maintained;

[0056] Or,

[0057] Step S222: When the current on - grid inverter's loaded power frequency period is greater than the maximum short - time current - limiting power frequency period, maintain the current operating state of the on - grid inverter.

[0058] In this step, the purpose of using the maximum short - time current - limiting power frequency period as the cycle threshold is to solve the problem of excessive transient current caused by suddenly adding a special load. Refer to Figure 2 , when the current on - grid inverter's loaded power frequency period is less than or equal to the maximum short - time current - limiting power frequency period, it means that at the peak of the inverter voltage, due to the characteristics of the BUCK circuit, the wave - generating time of the drive circuit calculated by the control chip will reach the maximum value. At this time, this wave - generating time is greater than the sampling delay Tdelay of the sampling circuit, that is, the wave - closing delay of the inverter circuit is limited by the sampling delay Tdelay. However, at this time, since the first current - limiting point (corresponding to the first preset current - limiting threshold) is small, the peak current can be effectively limited. On the contrary, if the current on - grid inverter's loaded power frequency period is greater than the maximum short - time current - limiting power frequency period, it exceeds the preset time limit for continuous current - limiting. In order to prevent the situation where the load cannot obtain the starting power and cannot start up, in this case, no current - limiting control is performed and normal loading is executed.

[0059] It should be noted that the specific value of the maximum short - time current - limiting power frequency period can be set accordingly according to the actual application scenario, and there is no limitation here. For example, it can be set to any value greater than 1 loaded power frequency period and less than 3 loaded power frequency periods, preferably set to 3 loaded power frequency periods. This is considered by the applicant based on actual experience. That is, when it exceeds 3 loaded power frequency periods, the double - load situation may be unstable because the time for the on - grid inverter to resist double - load is limited, generally 200ms, and the power during current - limiting is small, so it cannot be current - limited for a long time. Taking the air - conditioner load as an example, 3 loaded power frequency periods are the measured values. With short - time current - limiting within 3 loaded power frequency periods and then no current - limiting, the air - conditioner load can start successfully. If current - limiting continues for a long time, the air - conditioner load will not be able to obtain the starting power and cannot start up.

[0060] Such as Figure 4As shown, in one embodiment of the present invention, step S2 may but is not limited to include steps S23 to S25.

[0061] Step S23: When the real-time inverter current is greater than or equal to the second preset current limiting threshold, use the second preset current limiting threshold as the second current limiting point to perform a single-shot trigger protection on the off-grid inverter until the next load-carrying power frequency period of the off-grid inverter is reached. Here, the next load-carrying power frequency period of the off-grid inverter is determined according to the real-time operating conditions of the off-grid inverter under load. The single-shot trigger protection is the one-shot protection, which is characterized in that once triggered, it cannot automatically recover and will always be in the protection state until the OST bit in TZFLG is manually cleared;

[0062] Step S24: During the next load-carrying power frequency period of the off-grid inverter, soft-start the off-grid inverter and continuously obtain the real-time inverter current of the off-grid inverter, then return to execute step S23;

[0063] Step S25: Real-time monitor the number of cycles of executing step S23 and step S24, and perform current limiting control on the off-grid inverter according to the magnitude relationship between the number of cycles and the preset cycle protection number threshold.

[0064] In this step, by repeatedly executing step S23 and step S24, the peak current magnitude of the inverter circuit can be effectively limited. That is to say, referring to Figure 2 , during the repeated process of single-shot trigger protection, when it is first detected that the real-time inverter current is greater than or equal to the second preset current limiting threshold, at this time, the inverter voltage phase has not reached the peak. Due to the characteristics of the BUCK circuit, the wave generation time of the drive circuit calculated by the control chip has not reached the maximum value, that is, this wave generation time is less than the sampling delay Tdelay of the sampling circuit. At this time, the wave blocking delay of the inverter circuit is not limited by the sampling delay Tdelay, effectively limiting the peak current magnitude of the inverter circuit. At the same time, considering that the single-shot trigger protection shuts down the off-grid inverter once and for all, there may be false triggering situations. Therefore, a certain degree of loop execution steps are set to ensure that the off-grid inverter finally reaches a stable and good working state.

[0065] In one embodiment of the present invention, the step in step S25 of performing current limiting control on the off-grid inverter according to the magnitude relationship between the number of cycles and the preset cycle protection number threshold may but is not limited to include step S251 or S252.

[0066] Step S251: When the number of cycles is less than or equal to the preset cycle protection number threshold, continue to execute step S23 and step S24;

[0067] Or,

[0068] Step S252: When the number of cycles is greater than the preset cycle protection number threshold, the off-grid inverter is turned off.

[0069] In this step, considering that the single-trigger protection shuts down the off-grid inverter at one time, if the number of protection cycles is too small, the false triggering will affect the operating function of the off-grid inverter. However, if the number of cycles is too large, first of all, a large impact current will continue to exist, resulting in a certain amount of heat accumulation, causing the off-grid inverter temperature to rise. Therefore, a preset cycle protection number threshold is set for judgment. When the number of cycles is less than or equal to the preset cycle protection number threshold, the cycle step continues to be executed. Otherwise, it means that the protection of the off-grid inverter has reached the relative expectation, and there is no need to re-soft-start the off-grid inverter. Instead, the off-grid inverter is turned off and shut down for protection.

[0070] It should be noted that the specific value of the preset loop protection number threshold can be set accordingly according to the actual application scenario, and there is no restriction here. For example, it can be but not limited to being set to 3 times. According to actual experience, 3 cycles or so can basically eliminate false positives. Setting it to more may cause a waste of circuit resources and is unnecessary.

[0071] like Figure 5 As shown, in one embodiment of the present invention, step S2 may include but is not limited to step S26.

[0072] Step S26: When the real-time inverter current is less than the first preset current limiting threshold, the current operating state of the off-grid inverter is maintained.

[0073] In this step, if the real-time inverter current is less than the first preset current limiting threshold, it means that the real-time inverter current of the off-grid inverter meets the normal working requirements and does not need to be current limited. Therefore, the current operating state of the off-grid inverter is maintained, and normal load is executed at this time.

[0074] It should be noted that the steps of the above embodiments are not executed in a single manner. In different implementation scenarios, they can be combined and analyzed according to specific circumstances, so as to effectively and reliably control the off-grid inverter with load current limiting. For example, it can be but not limited to continuously monitoring the off-grid inverter for a preset period of time, and performing load current limiting control according to the actual situation during the monitoring process, such as Figure 6 As shown in FIG. 1 , a specific execution flow diagram of the load current limiting control method of an embodiment of the present invention is given. It can be seen that by continuously monitoring the off-grid inverter within the preset period, the load current limiting control can be effectively performed on it. Figure 6 The contents shown have been described in detail through the aforementioned embodiments, so they will not be repeated here.

[0075] Figure 7This is a schematic structural diagram of an electronic device 1000 provided by an embodiment of the present invention. As Figure 7 shown, the electronic device 1000 includes a memory 1100 and a processor 1200. The number of the memory 1100 and the processor 1200 may be one or more. Figure 7 Here, one memory 1100 and one processor 1200 are taken as an example; the memory 1100 and the processor 1200 in the device may be connected through a bus or other means. Figure 7 Here, the connection through a bus is taken as an example.

[0076] The memory 1100, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as program instructions / modules corresponding to the load current limiting control method of the off-grid inverter provided by any embodiment of the present invention. The processor 1200 realizes the above load current limiting control method of the off-grid inverter by running the software programs, instructions, and modules stored in the memory 1100.

[0077] The memory 1100 may mainly include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function. In addition, the memory 1100 may include high-speed random access memory and may also include non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other non-volatile solid-state storage devices. In some instances, the memory 1100 may further include a memory remotely set relative to the processor 1200, and these remote memories can be connected to the device through a network. Examples of the above network include but are not limited to the Internet, an enterprise intranet, a local area network, a mobile communication network, and combinations thereof.

[0078] An embodiment of the present invention also provides a computer-readable storage medium storing computer-executable instructions for executing the load current limiting control method of the off-grid inverter provided by any embodiment of the present invention.

[0079] An embodiment of the present invention also provides a computer program product including a computer program or computer instructions. The computer program or computer instructions are stored in a computer-readable storage medium. The processor of the computer device reads the computer program or computer instructions from the computer-readable storage medium, and the processor executes the computer program or computer instructions, so that the computer device executes the load current limiting control method of the off-grid inverter provided by any embodiment of the present invention.

[0080] The electronic devices and application scenarios described in the embodiments of the present invention are for more clearly illustrating the technical solutions of the embodiments of the present invention, and do not constitute a limitation on the technical solutions provided by the embodiments of the present invention. As can be known to those skilled in the art, with the evolution of electronic devices and the emergence of new application scenarios, the technical solutions provided by the embodiments of the present invention are equally applicable to similar technical problems.

[0081] Those of ordinary skill in the art can understand that all or some of the steps in the methods disclosed above, and the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, and appropriate combinations thereof.

[0082] In a hardware implementation, the division between the functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, one physical component can have multiple functions, or one function or step can be executed by several physical components in cooperation. Some or all physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or can be implemented as hardware, or can be implemented as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include a computer storage medium (or non-transitory medium) and a communication medium (or transitory medium). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory, or other memory technologies, CD-ROM, digital versatile disk (DVD), or other optical disk storage, magnetic cassette, tape, magnetic disk storage, or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, as is well known to those of ordinary skill in the art, a communication medium typically contains computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and can include any information delivery medium.

[0083] As used in this specification, the terms "component", "module", "system", etc. are used to denote a computer-related entity, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component can be, but is not limited to, a process running on a processor, a processor, an object, an executable, an execution thread, a program, or a computer. By way of illustration, both an application running on a computing device and the computing device can be components. One or more components can reside within a process or execution thread, and a component can be located on one computer or distributed between two or more computers. Moreover, these components can execute from various computer-readable media having various data structures stored thereon. A component can, for example, communicate by way of signals with other components through a local or remote process according to one or more data packets (e.g., data from two components interacting with another component from a local system, a distributed system, or a network, such as the Internet interacting with other systems by way of signals).

Claims

1. A load current limiting control method for an off-grid inverter, characterized in that, including the following steps: Step S1: When the off-grid inverter is in the on-load operation state, continuously obtain the real-time inverter current of the off-grid inverter and monitor the on-load real-time operation status of the off-grid inverter; Step S2: According to the magnitude relationship between the real-time inverter current and the first preset current-limiting threshold and the second preset current-limiting threshold, and combining the on-load real-time operation status of the off-grid inverter, perform current-limiting control on the off-grid inverter, where the first preset current-limiting threshold is less than the second preset current-limiting threshold; Among them, step S2 includes the following steps: Step S21: When the real-time inverter current is greater than or equal to the first preset current-limiting threshold and less than the second preset current-limiting threshold, determine the current on-load power frequency period of the off-grid inverter according to the on-load real-time operation status of the off-grid inverter; Step S22: According to the current on-load power frequency period of the off-grid inverter, perform current-limiting control on the off-grid inverter; Step S22 includes the following steps: Step S221: When the off-grid inverter is within the first three on-load power frequency periods, use the first preset current-limiting threshold as the first current-limiting point to perform cycle-by-cycle protection on the off-grid inverter; Or, Step S222: When the off-grid inverter is not within the first three on-load power frequency periods, maintain the current operation state of the off-grid inverter.

2. The on-load current limiting control method of the off-grid inverter according to claim 1, wherein Step S2 also includes the following steps: Step S23: When the real-time inverter current is greater than or equal to the second preset current-limiting threshold, use the second preset current-limiting threshold as the second current-limiting point to perform single-trigger protection on the off-grid inverter until the next on-load power frequency period of the off-grid inverter, where the next on-load power frequency period of the off-grid inverter is determined according to the on-load real-time operation status of the off-grid inverter; Step S24: In the next on-load power frequency period of the off-grid inverter, soft-start the off-grid inverter and continuously obtain the real-time inverter current of the off-grid inverter, and return to execute step S23; Step S25: Real-time monitor the number of cycles of executing step S23 and step S24, and perform current-limiting control on the off-grid inverter according to the magnitude relationship between the number of cycles and the preset cycle protection number threshold; 3. The load-carrying current limiting control method of the off-grid inverter according to claim 2, characterized in that, The steps in step S25, performing current-limiting control on the off-grid inverter according to the magnitude relationship between the number of cycles and the preset cycle protection number threshold, include the following steps: Step S251: When the number of cycles is less than or equal to the preset cycle protection number threshold, maintain the execution of step S23 and step S24; Or, Step S252: When the number of cycles is greater than the preset cycle protection number threshold, turn off the off-grid inverter.

4. The on-load current limiting control method of the off-grid inverter according to claim 1, wherein Step S2 also includes the following steps: Step S26: When the real-time inverter current is less than the first preset current-limiting threshold, maintain the current operation state of the off-grid inverter.

5. The load current limiting control method of the off-grid inverter according to any one of claims 1 to 4, characterized in that, The first preset current-limiting threshold is the inverter peak current of the off-grid inverter under the rated load, and the second preset current-limiting threshold is twice the first preset current-limiting threshold.

6. An electronic device, characterized in that, including: at least one processor; At least one memory for storing at least one program; When at least one of the at least one program is executed by at least one of the at least one processor, the on-load current limiting control method of the off-grid inverter according to any one of claims 1 to 5 is implemented.

7. A computer-readable storage medium, characterized in that, There is a program executable by a processor stored therein, and when the program executable by the processor is executed by the processor, it is used to implement the on-load current limiting control method of the off-grid inverter according to any one of claims 1 to 5.

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