A method and system for detecting battery disconnection in a hybrid photovoltaic-storage inverter system.

Abstract

This invention relates to the field of photovoltaic energy storage system technology, specifically to a battery disconnection detection method and system for a hybrid photovoltaic-energy storage inverter system. The method includes: an ADC sampling module acquiring real-time current and voltage sampling values ​​from the battery and sending them to the inverter's microcontroller module; the microcontroller module calculating the current loop output value based on the current setpoint and current sampling values ​​using a current loop PI controller; the microcontroller module calculating and generating a voltage sampling change difference based on real-time voltage sampling values ​​and initial voltage sampling values; and constructing a joint criterion group for disconnection detection. When all criterion conditions in the joint criterion group are simultaneously met and a preset judgment duration is maintained, the microcontroller module determines that a battery disconnection event has occurred and records the event. This method combines the dynamic response characteristics of the inverter control loop for comprehensive disconnection detection, offering advantages such as full operating condition coverage and rapid response.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic energy storage system technology, and more specifically to a battery disconnection detection method and system for a hybrid photovoltaic-energy storage inverter system. Background Technology

[0002] A hybrid photovoltaic-storage inverter system (referred to as "PV-storage integrated system") is an intelligent power device that integrates photovoltaic power generation, energy storage battery management, and bidirectional power conversion functions, serving as the "control center" of a photovoltaic energy storage system.

[0003] In hybrid photovoltaic-storage inverter systems, the inverter and battery exchange information via CAN communication, and the inverter adjusts its control measures based on the information obtained from the BMS (Battery Management System). However, due to factors such as cable aging, BMS active disconnection switches, or loose connectors, an abnormal situation may occur: the actual physical circuit between the inverter and the battery may be disconnected, for example, due to over-temperature protection actively disconnecting the internal contactor, or due to vibration causing the DC terminals to loosen.

[0004] When the physical circuit between the inverter and the battery is disconnected, the BMS detects the disconnection and sends it to the inverter. The inverter contains an MCU that outputs current loop control commands to control battery charging and discharging. It is known that there is a communication delay of several milliseconds in the process of the BMS sending the detected disconnection information to the inverter MCU. For normal communication, this delay is within the normal range. However, when the physical circuit between the inverter and the battery is disconnected, this delay causes the inverter MCU to be unable to adjust the output current loop control commands in time, resulting in distortion of the current loop control commands. This may cause power devices (IGBTs / MOSFETs) to overcurrent and break down due to voltage spikes generated by reverse recovery current or parasitic inductance in the open-circuit state, leading to a cascading failure. Summary of the Invention

[0005] The purpose of this invention is to provide a battery disconnection detection method and system for hybrid photovoltaic-storage inverter systems. This method performs disconnection detection in hybrid photovoltaic-storage inverter systems by fusing inverter control loop feature analysis with multi-modal criteria. It combines the dynamic response characteristics of the inverter control loop to comprehensively detect disconnection, and has the advantages of full operating condition coverage and fast response, thus having high practical value.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] In a first aspect, the present invention provides a battery disconnection detection method for a hybrid photovoltaic-storage inverter system, the method comprising:

[0008] The ADC sampling module collects the current and voltage sampling values ​​of the battery in real time and sends the current and voltage sampling values ​​to the microcontroller module.

[0009] The microcontroller module calculates the current loop output value based on the current setpoint and the current sample value through a current loop PI controller. The current loop output value reflects the controller saturation state caused by the accumulation of integral error.

[0010] The microcontroller module calculates and generates the voltage sampling change difference based on the real-time voltage sampling value and the initial voltage sampling value;

[0011] A joint criterion group for disconnection detection is constructed, which includes a first criterion condition generated based on a preset current threshold, a second criterion condition generated based on the dynamic calculation of the integral cumulative error of the current loop, and a third criterion condition generated based on the dynamic calculation of the PI control parameters of the bus voltage loop and the output value of the current loop.

[0012] When all criteria conditions in the joint criterion group for disconnection detection are met simultaneously, and the preset judgment duration T is continuously maintained... hold When the battery disconnection event occurs, the microcontroller module determines that the battery disconnection event has occurred and records the battery disconnection event.

[0013] As a preferred embodiment of the present invention, the first criterion condition is specifically as follows:

[0014] ≤

[0015] in, This is the current sample value. This is the first threshold.

[0016] As a preferred embodiment of the present invention, the second criterion is specifically as follows:

[0017] ≥

[0018]

[0019] in, This is the current loop output value. The second threshold, The current loop output value before the wire breakage , Set the current loop value. This is the proportionality coefficient of the current loop. The integral coefficient of the current loop is... For the time difference, For the current loop period, This is a margin parameter.

[0020] As a preferred embodiment of the present invention, the third criterion is specifically as follows:

[0021] ≥

[0022]

[0023]

[0024]

[0025] in, The third threshold, This is a sampled value of the battery voltage. It is the difference between the real-time voltage sample value and the initial voltage sample value. This is the boost factor. For adjustment coefficients, This is the bus voltage sample value. This is the proportional coefficient of the bus voltage loop. The integral coefficient of the bus voltage loop. The bus voltage setpoint, This is the bus voltage loop period.

[0026] As a preferred embodiment of the present invention, the preset determination time T hold The time length is the bus voltage loop period or the current loop period At least 20 times the length of time.

[0027] As a preferred embodiment of the present invention, the first threshold The value range is 0.01I. rated up to 0.03I rated , where I rated This is the battery's rated current.

[0028] As a preferred embodiment of the present invention, the battery disconnection detection method further includes a static battery disconnection detection step, specifically:

[0029] The ADC sampling module collects the battery voltage sampling value in real time; the microcontroller module determines the magnitude of the voltage sampling value and the minimum battery voltage threshold. When the voltage sampling value is less than the minimum battery voltage threshold, the microcontroller module determines that a battery disconnection event has occurred and records the battery disconnection event.

[0030] Secondly, the present invention also provides a battery disconnection detection system for a hybrid photovoltaic-storage inverter system, the system comprising:

[0031] The ADC sampling module is used to collect the current and voltage sampling values ​​of the battery in real time and send the current and voltage sampling values ​​to the microcontroller module of the inverter.

[0032] The microcontroller module is used to calculate the current loop output value based on the current setpoint and the current sample value through the current loop PI controller; it is also used to calculate and generate the voltage sampling change difference based on the real-time voltage sample value and the initial voltage sample value; when all the criteria conditions in the criterion group module are simultaneously met, and the preset judgment time T is continuously maintained... hold At the same time, the microcontroller module is also used to determine that the battery disconnection event has occurred and to record the battery disconnection event;

[0033] The criterion group module includes a first criterion condition unit generated based on a preset current threshold, a second criterion condition unit generated based on the dynamic calculation of the integral cumulative error of the current loop, and a third criterion condition unit generated based on the dynamic calculation of the PI control parameters of the bus voltage loop and the output value of the current loop.

[0034] Thirdly, the present invention also provides a storage medium storing a computer instruction program, which, when executed by a processor, causes the processor to perform the steps of the above-described method for detecting battery disconnection in a hybrid photovoltaic-storage inverter system.

[0035] Fourthly, the present invention also provides a computer device, including at least one memory and at least one processor, wherein the memory stores a computer instruction program, and when the computer instruction program is executed by the processor, the processor performs the steps of the above-described method for detecting battery disconnection in a hybrid photovoltaic-storage inverter system.

[0036] In summary, the present invention has the following beneficial effects:

[0037] This application overcomes the limitations of single-signal detection through a triple-criteria collaborative verification. The first criterion captures the physical disconnection characteristic of a sudden current drop to near zero using a preset current threshold. The second criterion dynamically analyzes the integral accumulation saturation state of the current loop PI controller, reflecting the continuous output distortion of control commands caused by path interruption. The third criterion dynamically calculates the voltage surge threshold by combining the bus voltage loop PI parameters, correlating abnormal fluctuations in the bus voltage after a disconnection. This criterion collaborative mechanism effectively distinguishes between battery disconnections and similar faults such as transient disturbances (e.g., load surges) and cell short circuits. It comprehensively detects disconnections by combining the dynamic response characteristics of the inverter control loop, offering advantages such as full-condition coverage and rapid response, and possesses high practical value. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a flowchart of the method of the present invention;

[0040] Figure 2 This is a system block diagram of the present invention;

[0041] Figure 3 This is a schematic diagram of the dynamic output state of the current loop under the charging condition in the embodiment.

[0042] Figure 4 This is a schematic diagram of the dynamic output state of the current loop corresponding to the second criterion condition under the charging condition in the embodiment.

[0043] Figure 5 This is a schematic diagram of the dynamic output state of the current loop corresponding to the third criterion condition under the charging condition in the embodiment.

[0044] Figure 6 This is a schematic diagram of the dynamic output state of the current loop corresponding to the second criterion condition under the discharge condition in the embodiment.

[0045] Figure 7 This is a schematic diagram of the dynamic output state of the current loop corresponding to the third criterion condition under the discharge condition in the embodiment.

[0046] Figure 8 This is a schematic diagram of the dynamic output state of the battery voltage sampling value and the minimum battery voltage threshold under static conditions in the embodiment. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0048] The terms “comprising” and “having”, and any variations thereof, in this specification, claims, and the foregoing drawings are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. Depending on the context, the word “if” as it applies herein may be interpreted as “when”, “in response to determination”, or “in response to detection”.

[0049] like Figure 1 The method shown is a battery disconnection detection method for a hybrid photovoltaic-storage inverter system, the method comprising:

[0050] The ADC sampling module acquires the battery's current sampling value I in real time. bat and voltage sampling value V bat The current sample value I is then sent to the microcontroller module; the microcontroller module can be implemented based on an MCU controller, whose built-in ADC conversion unit can convert the current sample value I... bat and voltage sampling value V bat It is converted into a data format that can be processed directly in real time.

[0051] The microcontroller module calculates the current loop output value based on the current setpoint and the current sample value through a current loop PI controller. The current loop output value reflects the controller saturation state caused by the accumulation of integral error.

[0052] The inverter MCU is based on the current setpoint I bat· Ref (i.e., the expected battery output current) and the actual sampled current I bat The output current command I is calculated using the PI controller. bat· If the circuit is disconnected, the actual current suddenly drops to 0, but the set current remains. The integral term of the PI controller will continue to accumulate errors, causing the output command to... An abnormal increase, i.e. "controller saturation".

[0053] The microcontroller module calculates and generates the voltage sampling change difference based on the real-time voltage sampling value and the initial voltage sampling value;

[0054] Inverter MCU calculates real-time battery voltage sampling value V bat The difference ∆V from the initial voltage bat When the battery disconnects, voltage fluctuations on the bus will be fed back to the battery terminals through the circuit, causing ∆V to... bat Significant changes.

[0055] A joint criterion group for disconnection detection is constructed, comprising a first criterion condition generated based on a preset current threshold, a second criterion condition generated based on dynamic calculation of the integral cumulative error of the current loop, and a third criterion condition generated based on dynamic calculation of the PI control parameters of the bus voltage loop and the output value of the current loop. When all criterion conditions in the joint criterion group for disconnection detection are simultaneously satisfied, and the preset judgment time T is maintained... hold When the battery disconnection event occurs, the microcontroller module determines that the battery disconnection event has occurred and records the battery disconnection event.

[0056] Existing technologies use fixed thresholds for judgment, which are easily affected by special operating conditions, leading to false judgments. For example, it is normal for the current to drop to zero at the moment of power-on. This embodiment provides three criteria to form a joint criterion group for disconnection detection. Disconnection detection is performed based on this joint criterion group, which can solve the above-mentioned problems.

[0057] Specifically, each criterion includes a judgment threshold. When all three criterions are met simultaneously, and the judgment duration is continuously preset for a period T... hold The MCU determines that the battery is disconnected and records the battery disconnection event, or triggers a protection mechanism (such as shutdown or switching to backup power) to prevent system crash.

[0058] The joint criteria group for wire breakage detection can perform wire breakage detection during both the charging and discharging phases of the battery.

[0059] The following embodiments provide a joint criterion set for detecting wire breakage during battery charging.

[0060] During charging, the battery current command is positive, and the battery current loop output value is also positive. When the battery is disconnected, the battery current feedback drops to near 0 (due to sampling error, this value will be very close to 0 but not equal to 0), unable to keep up with the given current. Due to the effect of the integral term, the battery current loop output value rapidly increases positively, even reaching saturation. The specific increase depends on the current current command. (The feedback rapidly decreases to 0, the difference between the feedback and the actual current rapidly widens, and the adjustment command increases until saturation).

[0061] The first criterion is to obtain the current sample value. With the first threshold To make a comparison, when ≤ That is, by setting a preset current threshold The physical characteristic of a sudden drop in current to near zero is captured as the first step in the determination.

[0062] Furthermore, since the larger the current command, the greater the difference between the given value and the feedback value of the current loop, and the faster the output value increases, the threshold of the second criterion should be a value that varies with the battery current command.

[0063] Before the battery disconnects, the current loop feedback keeps up with the given input, the proportional term is small, and the integral term maintains a constant value with slight oscillations. After the battery disconnects, the current loop feedback becomes zero, and the proportional term immediately increases. * The integral term increases with each calculation. * Therefore, the change in the current loop output value over time is as follows: Figure 3 As shown.

[0064] in, Set the current loop value. This is the proportionality coefficient of the current loop. The integral coefficient of the current loop is... This is the current loop output value. This is the upper limit of the current loop output value. This is the current loop output value before the wire breakage. The moment the line was disconnected. This is the time when the output reaches saturation.

[0065] to The relationship between the current loop output value and time over a given time period is given by equation (1), where The period is calculated for the current loop.

[0066] (1)

[0067] The second threshold in the second criterion condition It should be slightly smaller The value is as shown in equation (2), and its upper limit is The problem of different sensitivities of each system is solved by using a margin parameter e. In this embodiment, e=1 / 2 is selected.

[0068] (2)

[0069] The time difference equals and difference.

[0070] Therefore, the second threshold of the second criterion condition Changes over time, such as Figure 4 As shown:

[0071] As the battery current loop output value increases positively, the bus voltage loop setpoint also increases, the bus voltage rises, and the voltage at the inverter's battery interface, which is proportional to the bus voltage, also rises accordingly.

[0072] The bus voltage setpoint is given by equation (3):

[0073] (3)

[0074] in This is a sampled value of the battery voltage. For the boost factor, we have equation (4):

[0075] (4)

[0076] From equations (3) and (4), we can derive equation (5):

[0077] (5)

[0078] Based on the characteristics of PI modulation, it is not difficult to derive equation (6):

[0079] (6)

[0080] The relationship between the inverter bus voltage change and its loop output change is shown in equation (7). for Time and The difference in bus voltage from before, For a specific coefficient:

[0081] (7)

[0082] From equations (4), (6), and (7), we can derive equation (8). for Time and The difference between the previous battery voltage samples:

[0083] (8)

[0084] Then take equation (1) Substituting into equation (8), we can obtain equation (9), which is the relationship between the sampled change in battery voltage and time:

[0085] (9)

[0086] As shown in equation (8), the battery voltage sample value increases with the increase of the battery current loop output value. The threshold of the third criterion should be slightly smaller than the actual battery voltage sample value. Therefore, we take... Substituting into equation (8), we obtain the threshold for the third judgment condition as shown in equation (10):

[0087] (10)

[0088] Therefore, the changes in the battery voltage sampling value and the threshold of the third criterion over time are as follows: Figure 5 As shown:

[0089] in,

[0090] .

[0091] Therefore, in the case of a battery disconnection during charging, the three criteria are:

[0092] ≤

[0093] ≥

[0094] ≥

[0095] In another possible embodiment, a joint criterion set for detecting wire breakage under battery discharge is provided.

[0096] Unlike charging, discharging involves a negative battery current command, and the battery current loop output value is also negative. When the battery is disconnected, the battery current loop output value rapidly increases negatively. Therefore, the current loop output value... Second criterion threshold The relationship with time remains as shown in equations (1) and (2), as follows: Figure 6 As shown.

[0097] As the battery current loop output increases negatively, the bus voltage loop setpoint decreases, leading to a lower bus voltage. Consequently, the voltage at the inverter's battery interface, which is proportional to the bus voltage, also decreases. (Battery voltage sampling change value) and the third criterion threshold The relationship with time remains as shown in equations (9) and (10), as follows: Figure 7 As shown. Among them, ,

[0098] .

[0099] Therefore, during discharge, the three criteria are the same as those during charging when the battery is disconnected.

[0100] In summary, the joint criterion set for wire breakage detection provided by this application can be applied to all operating conditions, including charging and discharging.

[0101] In another possible embodiment, the battery may also be in a static state. Specifically, as... Figure 8As shown, when stationary, the battery current command is 0, and the battery current loop output value is also 0, so the loop has no effect on the battery port voltage. When the battery is disconnected, the battery voltage drops naturally. When the sampled battery voltage value falls below the inverter's minimum battery voltage threshold, the software triggers a battery disconnection event.

[0102] Figure 8 In the process, the judgment criteria for the battery disconnection detection steps can be: .

[0103] In this application, provided that all criterion conditions in the joint criterion group for disconnection detection are simultaneously met, it is also necessary to determine the duration, i.e., to continuously preset the determination time T. hold Only when the battery disconnection event is confirmed will the microcontroller module determine that the battery disconnection event has occurred and record the battery disconnection event.

[0104] In one possible implementation, the preset determination time T is set. hold The duration is 20 times the duration of the bus voltage loop cycle or the current loop cycle. If the duration continues for 20 battery current loop cycles or bus voltage loop cycles, the software will trigger a battery disconnection event and take corresponding measures to protect the inverter. Specifically, it can be taken as... , 20 times the maximum value in, due to , The range is typically 20µs to 400µs, so the detection time is less than 8ms.

[0105] Furthermore, in one possible implementation, the first threshold value ranges from 0.01I. rated up to 0.03I rated , where I rated This is the battery's rated current.

[0106] In one possible implementation, such as Figure 2 As shown, this embodiment provides a battery disconnection detection system for a hybrid photovoltaic-storage inverter system. The system includes:

[0107] The ADC sampling module is used to collect the current and voltage sampling values ​​of the battery in real time and send the current and voltage sampling values ​​to the microcontroller module of the inverter.

[0108] The microcontroller module is used to calculate the current loop output value based on the current setpoint and the current sample value through the current loop PI controller; it is also used to calculate and generate the voltage sampling change difference based on the real-time voltage sample value and the initial voltage sample value; when all the criteria conditions in the criterion group module are simultaneously met, and the preset judgment time T is continuously maintained... holdAt the same time, the microcontroller module is also used to determine that the battery disconnection event has occurred and to record the battery disconnection event;

[0109] The criterion group module includes a first criterion condition unit generated based on a preset current threshold, a second criterion condition unit generated based on the dynamic calculation of the integral cumulative error of the current loop, and a third criterion condition unit generated based on the dynamic calculation of the PI control parameters of the bus voltage loop and the output value of the current loop.

[0110] In one possible implementation, this embodiment provides a storage medium storing a computer instruction program, which, when executed by a processor, causes the processor to perform the steps of the battery disconnection detection method described above for a hybrid photovoltaic-storage inverter system.

[0111] In one possible implementation, this embodiment provides a computer device including at least one memory and at least one processor. The memory stores a computer instruction program, which, when executed by the processor, causes the processor to perform the steps of the above-described method for detecting battery disconnection in a hybrid photovoltaic-storage inverter system.

[0112] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this specification is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in or transmitted through a computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., Digital Versatile Discs (DVDs)), or semiconductor media (e.g., Solid State Disks (SSDs)).

[0113] Several embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical applications, or technological improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for detecting battery disconnection in a hybrid photovoltaic-storage inverter system, characterized in that, The methods include: The ADC sampling module collects the current and voltage sampling values ​​of the battery in real time and sends the current and voltage sampling values ​​to the microcontroller module. The microcontroller module calculates the current loop output value based on the current setpoint and the current sample value through a current loop PI controller. The current loop output value reflects the controller saturation state caused by the accumulation of integral error. The microcontroller module calculates and generates the voltage sampling change difference based on the real-time voltage sampling value and the initial voltage sampling value; A joint criterion group for disconnection detection is constructed, comprising a first criterion condition generated based on a preset current threshold, a second criterion condition generated based on dynamic calculation of the integral cumulative error of the current loop, and a third criterion condition generated based on dynamic calculation of the PI control parameters of the bus voltage loop and the output value of the current loop; the first criterion condition is specifically as follows: ≤ ;in, This is the current sample value. The first threshold is used; the second criterion is as follows: ≥ , ;in, This is the current loop output value. The second threshold, The current loop output value before the wire breakage , Set the current loop value. This is the proportionality coefficient of the current loop. The integral coefficient of the current loop is... For the time difference, For the current loop period, The margin parameter; the third criterion condition is specifically as follows: ≥ ; ; ; ;in, This is a sampled value of the battery voltage. The third threshold It is the difference between the real-time voltage sample value and the initial voltage sample value. This is the boost factor. For adjustment coefficients, This is the sampled value of the bus voltage. This is the proportional coefficient of the bus voltage loop. The integral coefficient of the bus voltage loop. The bus voltage setpoint, This represents the bus voltage loop period; When all criteria conditions in the joint criterion group for disconnection detection are met simultaneously, and the preset judgment duration T is continuously maintained... hold When the battery disconnection event occurs, the microcontroller module determines that the battery disconnection event has occurred and records the battery disconnection event.

2. The battery disconnection detection method for a hybrid photovoltaic-storage inverter system according to claim 1, characterized in that, The preset determination time T hold The time length is the bus voltage loop period or the current loop period 20 times the length of time.

3. The battery disconnection detection method for a hybrid photovoltaic-storage inverter system according to claim 2, characterized in that, The first threshold The value range is 0.01I. rated up to 0.03I rated , where I rated This is the battery's rated current.

4. The battery disconnection detection method for a hybrid photovoltaic-storage inverter system according to claim 1, characterized in that, This battery disconnection detection method also includes a static battery disconnection detection step, specifically: the ADC sampling module collects the battery voltage sampling value in real time; the microcontroller module determines the magnitude of the voltage sampling value and the minimum battery voltage threshold; when the voltage sampling value is less than the minimum battery voltage threshold, the microcontroller module determines that the battery disconnection event is established and records the battery disconnection event.

5. A battery disconnection detection system for a hybrid photovoltaic-storage inverter system, characterized in that, The system includes: an ADC sampling module, used to acquire the current and voltage sampling values ​​of the battery in real time, and send the current and voltage sampling values ​​to the microcontroller module; The microcontroller module is used to calculate the current loop output value based on the current setpoint and the current sample value through the current loop PI controller; it is also used to calculate and generate the voltage sampling change difference based on the real-time voltage sample value and the initial voltage sample value; when all the criteria conditions in the criterion group module are simultaneously met, and the preset judgment time T is continuously maintained... hold At the same time, the microcontroller module is also used to determine that the battery disconnection event has occurred and to record the battery disconnection event; The criterion group module includes a first criterion condition unit generated based on a preset current threshold, a second criterion condition unit generated based on dynamic calculation of the integral cumulative error of the current loop, and a third criterion condition unit generated based on dynamic calculation of the bus voltage loop PI control parameters and the current loop output value; the criterion specifically executed by the first criterion condition unit is: ≤ ;in, This is the current sample value. The first threshold is used; the second criterion condition unit specifically executes the following criterion: ≥ , ;in, This is the current loop output value. The second threshold, The current loop output value before the wire breakage , Set the current loop value. This is the proportionality coefficient of the current loop. The integral coefficient of the current loop is... For the time difference, For the current loop period, This is a margin parameter; the specific criterion executed by the third criterion condition unit is: ≥ ; ; ; ;in, This is a sampled value of the battery voltage. The third threshold It is the difference between the real-time voltage sample value and the initial voltage sample value. This is the boost factor. For adjustment coefficients, This is the sampled value of the bus voltage. This is the proportional coefficient of the bus voltage loop. The integral coefficient of the bus voltage loop. The bus voltage setpoint, This is the bus voltage loop period.

6. A storage medium, characterized in that, The system stores a computer instruction program, which, when executed by a processor, causes the processor to perform the steps of a battery disconnection detection method for a hybrid photovoltaic-storage inverter system as described in any one of claims 1-4.

7. A computer device, characterized in that, It includes at least one memory and at least one processor, the memory storing a computer instruction program, which, when executed by the processor, causes the processor to perform the steps of the battery disconnection detection method for a hybrid photovoltaic-storage inverter system as described in any one of claims 1-4.

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