A BMS mid-end security protection circuit system and method

Abstract

The object of the present invention is to provide a BMS mid-end safety protection circuit system and method. First, the force exerted by the lithium battery module on the cavity is obtained according to the pressure control module, and the working state of the pressure relief valve is adjusted through the pressure control module according to the pressure information to avoid damage to the battery cells due to excessive pressure. Then, the temperature of the lithium battery is detected according to the temperature control module, and the cooler and the blowing state controlled by the temperature control module are adjusted in real time according to the temperature value of the lithium battery to ensure the working temperature of the lithium battery. Finally, the power supply power of the lithium battery is adjusted in real time through the output control module, and the output channel state of the lithium battery is cut off in an emergency state to protect the electrical appliances. Through the BMS mid-end safety protection method, the present invention improves the stability of the power supply system and the operation and maintenance efficiency of the power supply product.

Description

Technical Field

[0001] The present invention relates to the field of battery control, and more specifically, to a BMS mid-end safety protection circuit system and method. Background Art

[0002] ‌BMS, fully known as BATTERY MANAGEMENT SYSTEM, that is, battery management system, is widely used in the power supply field. Especially in UPS (Uninterruptible Power Supply), it plays a crucial role in controlling lithium battery modules. As a core IT device, UPS plays a crucial role in ensuring the power supply safety required for the normal operation of the data center. When various faults occur in the power grid, UPS outputs high-quality power through the configured battery after AC inversion to avoid data loss or task interruption caused by power interruption.

[0003] In the installation, operation and other links of lithium batteries, which are called the mid-end links of BMS, the traditional operation and maintenance means are on-site manual installation and repair, which have the defects of manual operation. To improve mid-end safety, BMS mid-end safety protection can be adopted to improve the stability of the entire battery system. There is an urgent need for a BMS mid-end safety protection technology that can improve the stability of the power system and the operation and maintenance efficiency of power products. Summary of the Invention

[0004] In view of the above problems, the purpose of the present invention is to provide a BMS mid-end safety protection circuit system and method. First, according to the pressure control module, obtain the magnitude of the force exerted by the lithium battery module on the cavity, and adjust the working state of the pressure relief valve through the pressure control module according to the pressure information to avoid damage to the battery cells due to excessive pressure; then, according to the temperature control module, detect the temperature of the lithium battery, and adjust the cooling and blowing states controlled by the temperature control module in real time according to the temperature value of the lithium battery to ensure the working temperature of the lithium battery; finally, through the output control module, adjust the power supply power of the lithium battery in real time, and cut off the output channel state of the lithium battery in an emergency to protect the electrical appliances; the present invention improves the stability of the power system and the operation and maintenance efficiency of power products through the BMS mid-end safety protection method.

[0005] The first aspect of the present invention provides a BMS mid-end safety protection circuit system, and the circuit system includes:

[0006] A pressure control module, a temperature control module and an output control module;

[0007] The pressure control module includes a pressure sensor circuit for detecting the interaction force between the battery and the housing, and a pressure relief valve control circuit for controlling the pressure relief state of the pressure relief valve according to the set pressure relief parameters;

[0008] The temperature control module includes a temperature detection circuit for detecting the temperature value of the lithium battery, and a heat dissipation control circuit for adjusting the refrigeration effect and the air volume according to the heat dissipation parameters;

[0009] The output control module includes a current limiting control circuit for controlling the supply current, and an output isolation circuit for switching the output conduction state of the lithium battery.

[0010] In this solution, the pressure control module is specifically:

[0011] It includes a sensor circuit and a pressure relief valve control circuit;

[0012] The pressure sensor circuit is a sensor circuit that converts the interaction force between the battery and the housing into an analog-to-digital conversion value;

[0013] The pressure relief valve control circuit is a control circuit that adjusts the pressure relief state according to the PWM signal

[0014] In this solution, the temperature control module is specifically:

[0015] It includes a temperature detection circuit and a heat dissipation control circuit;

[0016] The temperature detection circuit is a temperature sensor or a thermistor circuit for detecting the temperature value of the lithium battery;

[0017] The heat dissipation control circuit is a drive circuit for controlling the refrigeration power of the cooler and the air volume of the blower.

[0018] In this solution, the output control module is specifically:

[0019] An output isolation circuit and a current limiting control circuit;

[0020] The output isolation circuit controls the conduction relay through a bypass isolation circuit for switching the output conduction state of the lithium battery;

[0021] The current limiting control circuit adjusts the supply current of the lithium battery by adjusting the feedback resistance of the current limiting control circuit.

[0022] The second aspect of the present invention provides a BMS mid-end safety protection method, and the method includes:

[0023] Obtain the first pressure information;

[0024] Judge whether the first pressure information is greater than a preset first pressure threshold;

[0025] If so, control the working state of the pressure relief valve according to the first pressure information;

[0026] Determine the first air volume upper limit threshold according to the working state of the pressure relief valve;

[0027] Obtain the first temperature information;

[0028] Determine whether the first temperature information exceeds a preset standard temperature value;

[0029] If so, obtain the first air volume information and the first refrigeration information according to the first temperature information and the standard temperature value;

[0030] Determine whether the first air volume information exceeds the first air volume upper limit threshold;

[0031] If so, adjust the first air volume information according to the first air volume information and the first air volume upper limit threshold;

[0032] Set the first refrigeration information according to the first air volume upper limit threshold.

[0033] In this solution, the control of the working state of the pressure relief valve according to the first pressure information is specifically as follows:

[0034] Collect and record the first pressure information according to a preset first time period to obtain a first pressure sequence;

[0035] Determine the first slope information according to the first pressure sequence;

[0036] Obtain the pressure relief parameter information according to the first slope information;

[0037] Control the working state of the pressure relief valve according to the pressure relief parameter information.

[0038] In this solution, the determination of the first air volume upper limit threshold according to the working state of the pressure relief valve is specifically as follows:

[0039] Obtain the first slope information;

[0040] Determine whether the first slope information exceeds a preset first slope threshold;

[0041] If so, select the first air volume corresponding table for the air volume threshold table;

[0042] If not, select the second air volume corresponding table for the air volume threshold table;

[0043] Obtain the pressure relief parameter information;

[0044] Determine the first air volume upper limit threshold according to the pressure relief parameter information and the air volume threshold table.

[0045] In this solution, the obtaining of the first air volume information and the first refrigeration information according to the first temperature information and the standard temperature value is specifically as follows:

[0046] Collect the first temperature information according to a preset first time period;

[0047] Calculate the difference between the first temperature information and the standard temperature value to obtain the first temperature deviation information;

[0048] According to the first temperature deviation information and the set first control weight, obtain the first proportional control quantity, the first integral control quantity, and the first derivative control quantity;

[0049] According to the first proportional control quantity, the first integral control quantity, and the first derivative control quantity, obtain the first air volume control quantity;

[0050] According to the first air volume control quantity, update to obtain the first air volume information.

[0051] In this solution, the obtaining of the first air volume information and the first refrigeration information according to the first temperature information and the standard temperature value is specifically as follows:

[0052] Collect the first temperature information according to the preset second time period;

[0053] Calculate the difference between the first temperature information and the standard temperature value to obtain the first temperature deviation information;

[0054] According to the first temperature deviation information and the set second control weight, obtain the second proportional control quantity and the second integral control quantity;

[0055] According to the second proportional control quantity and the second integral control quantity, obtain the first refrigeration control quantity;

[0056] According to the first refrigeration control quantity, update to obtain the first refrigeration information.

[0057] In this solution, the adjustment of the first refrigeration information according to the first air volume information and the first air volume upper limit threshold is specifically as follows:

[0058] Calculate the difference between the first air volume information and the first air volume upper limit threshold to obtain the first air volume deviation information;

[0059] According to the first air volume deviation information, determine the first refrigeration adjustment quantity;

[0060] According to the first refrigeration adjustment quantity, adjust the first refrigeration information.

[0061] The object of the present invention is to provide a BMS mid - end safety protection circuit system and method. First, the force exerted by the lithium - battery module on the cavity is obtained according to the pressure control module, and the working state of the pressure relief valve is adjusted through the pressure control module according to the pressure information to avoid damage to the battery cells due to excessive pressure. Then, the temperature of the lithium - battery is detected according to the temperature control module, and the cooling device and the blowing state controlled by the temperature control module are adjusted in real - time according to the temperature value of the lithium - battery to ensure the working temperature of the lithium - battery. Finally, the power supply power of the lithium - battery is adjusted in real - time through the output control module, and the output channel state of the lithium - battery is cut off in an emergency state to protect the electrical appliances. Through the BMS mid - end safety protection method of the present invention, the stability of the power supply system is improved and the operation and maintenance efficiency of the power supply product is enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope.

[0063] Figure 1 The block diagram of a BMS mid - end safety protection circuit system of the present invention is shown;

[0064] Figure 2 The flowchart of a BMS mid - end safety protection method of the present invention is shown;

[0065] Figure 3 The control flowchart of the pressure relief valve provided by the embodiment of the present invention is shown;

[0066] Figure 4 The determination flowchart of the first upper limit threshold of the air volume provided by the embodiment of the present invention is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0067] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0068] Unless otherwise defined, all terms (including technical and scientific terms) used in the embodiments of the present invention have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be interpreted as having a meaning consistent with their meaning in the context of the related art and should not be interpreted in an idealized or overly formal sense unless clearly defined in the embodiments of the present invention.

[0069] In the embodiments of the present invention, words such as "first", "second" and the like do not denote any order, quantity or importance, but are merely used to distinguish different components. Words such as "a", "an" or "the" do not denote a quantity limitation either, but mean that there is at least one. Similarly, words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The steps before or after the method of the embodiments of the present invention do not necessarily have to be carried out precisely in order. On the contrary, they can be carried out in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or several steps can be removed from these processes.

[0070] In addition, in each embodiment of the present invention, the various functional modules can be integrated together to form an independent part, or each module can exist alone, or two or more modules can be integrated to form an independent part.

[0071] Figure 1 A block diagram of a mid-end safety protection circuit system of a BMS according to the present invention is shown.

[0072] As Figure 1 shown, in a first aspect of the present invention, a mid-end safety protection method for a BMS is disclosed, and the method includes:

[0073] A pressure control module 101, a temperature control module 102, and an output control module 103;

[0074] The pressure control module 101 is a pressure sensor circuit for detecting the interaction force between the battery and the housing, and a pressure relief valve control circuit for controlling the pressure relief state of the pressure relief valve according to the set pressure relief parameters;

[0075] The temperature control module 102 is a temperature detection circuit for detecting the temperature value of the lithium battery, and a heat dissipation control circuit for adjusting the refrigeration effect and the air volume according to the heat dissipation parameters;

[0076] The output control module 103 is a current limiting control circuit for controlling the supply current, and an output isolation circuit for switching the conduction state of the lithium battery output.

[0077] It should be noted that in this embodiment, the BMS mid-end safety protection circuit is composed of a pressure control module, a temperature control module, and an output control module. The pressure control module is used to detect the pressure of the interaction force between the battery and the housing, and at least includes pressure sensors equal in number to the lithium battery modules to measure the pressure of each lithium battery on the housing. The pressure control module controls the pressure relief state of the pressure relief valve through a pressure relief valve control circuit according to the set pressure relief parameters, achieving the effect of reducing the pressure of the housing on the lithium battery. The temperature control module is used to detect the temperature value of the lithium battery, and at least includes temperature detection elements equal in number to the lithium battery modules to measure the real-time temperature value of each lithium battery. The temperature control module also adjusts the refrigeration of the refrigerator and the air volume of the blower according to the heat dissipation parameters. The output control module is used to adjust the output current of the lithium battery and to achieve the function of disconnecting the output conduction state in case of emergency.

[0078] According to an embodiment of the present invention, the pressure control module is specifically:

[0079] It includes a sensor circuit and a pressure relief valve control circuit;

[0080] The pressure sensor circuit is a sensor circuit that converts the interaction force between the battery and the housing into an analog-to-digital conversion value;

[0081] The pressure relief valve control circuit is a control circuit that adjusts the pressure relief state according to the PWM signal.

[0082] It should be noted that in this embodiment, the pressure sensor outputs an analog quantity, which is amplified and filtered by the circuit and then converted into a digital quantity by the analog-to-digital converter and handed over to the CPU for processing; among them, the magnitude of the digital quantity is directly related to the magnitude of the pressure value. Generally speaking, the larger the pressure value, the larger the digital quantity. The control input signal of the pressure relief valve control circuit is the PWM signal. Among them, the higher the duty cycle of the PWM signal, the larger the opening of the pressure relief valve, that is, the more obvious the pressure relief effect.

[0083] According to an embodiment of the present invention, the temperature control module is specifically:

[0084] It includes a temperature detection circuit and a heat dissipation control circuit;

[0085] The temperature detection circuit is a temperature sensor or a thermistor circuit for detecting the temperature value of the lithium battery;

[0086] The heat dissipation control circuit is a drive circuit for controlling the refrigeration power of the refrigerator and the air volume of the blower.

[0087] It should be noted that the temperature detection circuit is a temperature sensor or a thermistor circuit. When it is a temperature sensor, such as DS18B20, the temperature value of the sensor can be obtained through preset communication instructions; when it is a thermistor circuit, the temperature value of the thermistor can be obtained by detecting the resistance value of the thermistor and using the look-up table method. The heat dissipation control circuit is used to control the temperature value of the heat conduction medium and the operating speed of the heat conduction medium in the heat dissipation system. In the air-cooled system, the heat dissipation control circuit controls the refrigeration power of the cooler to adjust the temperature value of the heat-conducting air; the heat dissipation control circuit controls the air volume of the blower to adjust the operating speed of the heat-conducting air.

[0088] According to an embodiment of the present invention, the output control module is specifically:

[0089] An output isolation circuit and a current-limiting control circuit;

[0090] The output isolation circuit controls the conduction relay through a bypass isolation circuit and is used to switch the output conduction state of the lithium battery;

[0091] The current-limiting control circuit adjusts the feedback resistance of the current-limiting control circuit to adjust the supply current of the lithium battery.

[0092] It should be noted that the output isolation circuit controls the conduction of the lithium battery output through a bypass isolation circuit to control the conduction relay, and is used to disconnect the connection between the lithium battery and the electrical equipment in case of emergency, improving the safety of lithium battery use. The current-limiting control circuit adjusts the feedback resistance of the current-limiting control circuit to adjust the supply current of the lithium battery, so as to adjust the output of each lithium battery module, that is, to adjust the heat generation of each lithium battery module, thereby improving the service life of the lithium battery.

[0093] It is worth mentioning that it also includes:

[0094] An anti-reverse connection circuit and a surge protection circuit;

[0095] The anti-reverse connection circuit is a voltage detection conduction circuit used to prevent the reverse connection of the positive and negative voltage poles;

[0096] The surge protection circuit uses an enhanced MOSFET charge pump to improve the circuit stability.

[0097] It should be noted that the anti-reverse connection circuit is used to detect the positive and negative poles of the voltage. When the positive and negative poles are correctly connected, it is in the conduction state and the voltage conducts normally; when the positive and negative poles are reversely connected, it is in the cut-off state and the voltage cannot conduct. The surge protection circuit uses an enhanced MOSFET charge pump to improve the voltage resistance of the circuit to withstand instantaneous high voltages such as static electricity and surges.

[0098] Figure 2The flowchart of a mid - end security protection method of the present invention is shown.

[0099] As Figure 2 shown, in the second aspect of the present invention, a mid - end security protection method for BMS is disclosed. The method includes:

[0100] S202, obtaining first pressure information;

[0101] S204, determining whether the first pressure information is greater than a preset first pressure threshold;

[0102] S206, if so, controlling the working state of the pressure relief valve according to the first pressure information;

[0103] S208, determining a first upper limit threshold of air volume according to the working state of the pressure relief valve;

[0104] S210, obtaining first temperature information;

[0105] S212, determining whether the first temperature information exceeds a preset standard temperature value;

[0106] S214, if so, obtaining first air volume information and first refrigeration information according to the first temperature information and the standard temperature value;

[0107] S216, determining whether the first air volume information exceeds the first upper limit threshold of air volume;

[0108] S218, if so, adjusting the first air volume information according to the first air volume information and the first upper limit threshold of air volume;

[0109] S220, setting the first refrigeration information according to the first upper limit threshold of air volume.

[0110] It should be noted that the first pressure information is the magnitude of the interaction force between the lithium battery and the housing; the first upper limit threshold of air volume is the upper limit value of the air volume parameter of the blower; the first temperature information is the temperature value of the lithium battery; the first air volume information is the set parameter for adjusting the air - blowing speed of the blower, that is, the air volume per unit time; the first refrigeration information is the set parameter for adjusting the refrigeration working state of the refrigerator.

[0111] In this embodiment, first, the first pressure information is obtained through a pressure sensor. When the first pressure information exceeds the preset first pressure threshold, it indicates that the mutual force between the lithium battery and the housing is too high due to heat expansion, transportation vibration, etc. of the lithium battery. It is necessary to release the pressure in time to avoid damage to the battery core of the lithium battery, thereby extending the service life of the lithium battery. The working state of the pressure relief valve is controlled according to the first pressure information, that is, the mutual force between the housing and the lithium battery is reduced. Secondly, according to the working state of the pressure relief valve, the first upper limit threshold of the air volume is determined; when in the pressure relief state, the heat dissipation channel will be opened, and there is a phenomenon that the hot air in the heat dissipation channel is taken out of the housing; at this time, this embodiment adopts a method of controlling the air volume to avoid blowing too much hot air out of the housing and reduce the danger to users or operators near the power supply equipment. Then, the first temperature information of the lithium battery is obtained through a temperature detection circuit. According to the relationship between the first temperature information and the standard temperature value, and in accordance with the set heat dissipation adjustment strategy, the first air volume information and the first refrigeration information are calculated. Finally, it is judged whether the first air volume information exceeds the first upper limit threshold of the air volume; if not, the cooler and the blower are set according to the first air volume information and the first refrigeration information; if not, the first air volume information needs to be adjusted according to the first upper limit threshold of the air volume, and then the first refrigeration information is adjusted according to the adjusted first air volume information, and the cooler and the blower are set according to the adjusted first air volume information and the first refrigeration information. By adaptively adjusting the heat dissipation control circuit, it is ensured that the lithium battery works within a safe temperature range to extend the service life of the lithium battery.

[0112] Figure 3 The control flow chart of the pressure relief valve provided by the embodiment of the present invention is shown.

[0113] According to the embodiment of the present invention, as Figure 3 shown, the controlling the working state of the pressure relief valve according to the first pressure information is specifically:

[0114] S302, collect and record the first pressure information according to a preset first time period to obtain a first pressure sequence;

[0115] S304, determine the first slope information according to the first pressure sequence;

[0116] S306, obtain the pressure relief parameter information according to the first slope information;

[0117] S308, control the working state of the pressure relief valve according to the pressure relief parameter information.

[0118] It should be noted that in this embodiment, according to the first pressure information, the expansion trend of the lithium battery in the housing is analyzed to determine the pressure relief parameters of the pressure relief valve. In practical applications, if the opening of the pressure relief valve is too small, there will be a problem of insufficient pressure relief effect; if the opening of the pressure relief valve is too large, there will be a lack of limit support between the lithium battery and the housing, and there is a risk of displacement of the lithium battery. Therefore, in this embodiment, the first pressure information is collected and recorded according to a preset first time period to obtain a first pressure sequence. Then, according to the first pressure sequence, a pressure change curve is obtained by curve fitting; and then, according to the pressure change curve, the first slope information is obtained; wherein, the first slope information can represent the trend of pressure change, and the larger the slope, the faster the pressure rises. Finally, according to the first slope information, a preset pressure relief parameter correspondence table is searched to obtain pressure relief parameter information, that is, the PWM duty ratio, which is used to control the working state of the pressure relief valve.

[0119] Figure 4 The flowchart for determining the first upper air volume threshold provided by the embodiment of the present invention is shown.

[0120] According to the embodiment of the present invention, as Figure 4 shown, determining the first upper air volume threshold according to the working state of the pressure relief valve specifically includes:

[0121] S402, obtain the first slope information;

[0122] S404, determine whether the first slope information exceeds a preset first slope threshold;

[0123] S406, if so, select the first air volume correspondence table for the air volume threshold table;

[0124] S408, if not, select the second air volume correspondence table for the air volume threshold table;

[0125] S410, obtain the pressure relief parameter information;

[0126] S412, determine the first upper air volume threshold according to the pressure relief parameter information and the air volume threshold table.

[0127] It should be noted that in this embodiment, first, an air volume threshold table is selected according to the pressure change trend, and then, according to the pressure relief parameter information, the first upper air volume threshold is determined. First, the slope information of the pressure change curve is obtained; then, it is judged whether the first slope information exceeds a preset first slope threshold; wherein, the first slope threshold is 0, that is to say, when the first slope is greater than 0, it indicates that the pressure value is still in an ascending state, the internal pressure is relatively large and can abut against the opening of the pressure relief valve, and the heat-conducting air is not easy to flow out, so a relatively large air volume for blowing can be set, and the first air volume corresponding table is selected as the air volume threshold table; when the first slope information is less than 0, it indicates that the pressure value is in a descending state, the internal pressure is relatively small and it is difficult to abut against the opening of the pressure relief valve, and the heat-conducting air is easy to flow out, so a relatively small air volume for blowing needs to be set, and the second air volume corresponding table is selected as the air volume threshold table. Finally, according to the pressure relief parameter information, the air volume threshold table is searched to obtain the first upper air volume threshold.

[0128] According to an embodiment of the present invention, the obtaining of the first air volume information and the first refrigeration information according to the first temperature information and the standard temperature value is specifically as follows:

[0129] Collect the first temperature information according to a preset first time period;

[0130] Calculate the difference between the first temperature information and the standard temperature value to obtain the first temperature deviation information;

[0131] According to the first temperature deviation information and a set first control weight, obtain a first proportional control amount, a first integral control amount and a first differential control amount;

[0132] According to the first proportional control amount, the first integral control amount and the first differential control amount, obtain a first air volume control amount;

[0133] According to the first air volume control amount, update to obtain the first air volume information.

[0134] It should be noted that as an implementation manner, this embodiment adopts a feedback control strategy to adjust the first air volume information of the blower. First, calculate the difference between the first temperature information and the standard temperature value according to a preset first time period to obtain the first temperature deviation information. The first control weight includes a first proportional control weight, a first integral control weight and a first differential control weight. Then, according to the first temperature deviation value and the set first proportional control weight, obtain the first proportional control amount; according to the integral value of the first temperature deviation value and the set first integral control weight, obtain the first integral control amount; according to the differential value of the first temperature deviation value and the set first differential control weight, obtain the first differential control amount. Finally, calculate the sum of the first proportional control amount, the first integral control amount and the first differential control amount to obtain the first air volume control amount, which is used to update to obtain the first air volume information.

[0135] According to an embodiment of the present invention, obtaining the first air volume information and the first refrigeration information based on the first temperature information and the standard temperature value specifically includes:

[0136] Collecting the first temperature information according to a preset second time period;

[0137] Calculating the difference between the first temperature information and the standard temperature value to obtain the first temperature deviation information;

[0138] Obtaining a second proportional control quantity and a second integral control quantity according to the first temperature deviation information and a set second control weight value;

[0139] Obtaining a first refrigeration control quantity according to the second proportional control quantity and the second integral control quantity;

[0140] Updating to obtain the first refrigeration information according to the first refrigeration control quantity.

[0141] It should be noted that, as an implementation manner, this embodiment adopts another feedback control strategy to adjust the first refrigeration information of the refrigerator. First, calculate the difference between the first temperature information and the standard temperature value according to a preset second time period to obtain the first temperature deviation information, where the second time period is slower than the first time period. The second control weight value includes a second proportional control weight value and a second integral control weight value. Then, obtain a second proportional control quantity according to the first temperature deviation value and the set second proportional control weight value; obtain a second integral control quantity according to the integral value of the first temperature deviation value and the set second integral control weight value. Finally, calculate the sum of the second proportional control quantity and the second integral control quantity to obtain the first refrigeration control quantity for updating to obtain the first refrigeration information.

[0142] According to an embodiment of the present invention, adjusting the first refrigeration information according to the first air volume information and the first air volume upper limit threshold specifically includes:

[0143] Calculating the difference between the first air volume information and the first air volume upper limit threshold to obtain the first air volume deviation information;

[0144] Determining a first refrigeration adjustment quantity according to the first air volume deviation information;

[0145] Adjusting the first refrigeration information according to the first refrigeration adjustment quantity.

[0146] It should be noted that when the first air volume information exceeds the first air volume upper limit threshold and the first air volume information and the first refrigeration information need to be adjusted, first, the difference between the first air volume information and the first air volume upper limit threshold is obtained to get the first air volume deviation information, which is used to represent the air volume value that needs to be reduced and the air volume value that needs to compensate by reducing the temperature of the heat-conducting medium. Then, the corresponding refrigeration adjustment table is searched to obtain the first refrigeration adjustment amount. Finally, according to the first refrigeration adjustment amount, the first refrigeration information is adjusted to achieve the effect of compensating the air volume by cooling.

[0147] It is worth mentioning that it further includes:

[0148] Obtain the first temperature information;

[0149] Determine whether the first temperature information exceeds a preset first temperature threshold;

[0150] If so, adjust the first control weight or the second control weight according to the first temperature information.

[0151] It should be noted that due to the lag effect of heat transfer, in this embodiment, the control weight of the adjustment feedback control strategy is adjusted to adjust the efficiency and stability of temperature adjustment. When the first temperature information exceeds the preset first temperature threshold, the control weight adjustment strategy can be executed. By looking up the table, the first control weight or the second control weight is determined. When the temperature deviation value is large, a high proportional weight and a low integral weight are used to improve the efficiency of temperature adjustment; when the temperature deviation value is small, a low proportional weight and a high integral weight are used to improve the stability of temperature change; thus, the efficiency and stability of temperature adjustment are improved.

[0152] It is worth mentioning that it further includes:

[0153] Obtain the first pressure information;

[0154] Determine whether the first pressure information is greater than a preset second pressure threshold;

[0155] If so, disconnect the output conduction state of the lithium battery.

[0156] It should be noted that in this embodiment, when the first pressure information exceeds the preset second pressure threshold, it means that the battery expands excessively or is deformed severely due to external force, and there is a risk of burning or short circuit. At this time, the output conduction state of the lithium battery is disconnected through the output isolation circuit to reduce the use risk of the electrical equipment.

[0157] It is worth mentioning that it further includes:

[0158] Obtain the first temperature information;

[0159] Determine whether the first temperature information exceeds a preset second temperature threshold;

[0160] If so, adjust the supply current of the lithium battery according to the first temperature information;

[0161] Determine whether the first temperature information exceeds a preset third temperature threshold;

[0162] If so, disconnect the output conduction state of the lithium battery.

[0163] It should be noted that in this embodiment, when the first temperature information exceeds the preset second temperature threshold, it means that the lithium battery is in an output heating state. Then, the supply current of the lithium battery is adjusted according to the first temperature information to reduce the heating of the lithium battery. When the first temperature information exceeds the preset third temperature threshold, it means that there is a problem of over-temperature caused by a short circuit. At this time, the output conduction state of the lithium battery is disconnected through the output isolation circuit to reduce the use risk of the electrical equipment.

[0164] The purpose of the present invention is to provide a BMS mid-end safety protection circuit system and method. First, the pressure control module is used to obtain the magnitude of the force exerted by the lithium battery module on the cavity, and the working state of the pressure relief valve is adjusted according to the pressure information through the pressure control module to prevent the battery cells from being damaged due to excessive pressure. Then, the temperature control module is used to detect the temperature of the lithium battery, and the cooling device and the blowing state controlled by the temperature control module are adjusted in real time according to the temperature value of the lithium battery to ensure the working temperature of the lithium battery. Finally, the output control module is used to adjust the supply power of the lithium battery in real time and cut off the output channel state of the lithium battery in an emergency to protect the electrical appliances. The present invention improves the stability of the power system and the operation and maintenance efficiency of the power product through the BMS mid-end safety protection method.

[0165] If the above functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical disks and other various media that can store program codes.

[0166] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A BMS mid-end safety protection method is applied to a BMS mid-end safety protection circuit system, the circuit system comprising: Pressure control module, temperature control module and output control module; The pressure control module includes a pressure sensor circuit for detecting the interaction force between the battery and the housing, and a pressure relief valve control circuit for controlling the pressure relief state of the pressure relief valve according to the set pressure relief parameters; The temperature control module includes a temperature detection circuit for detecting the temperature value of the lithium battery, and a heat dissipation control circuit for adjusting the cooling effect and air volume according to the heat dissipation parameters; The output control module includes a current limiting control circuit for controlling the power supply current, and an output isolation circuit for switching the output conduction state of the lithium battery; Characterized in that the method comprises: obtaining first pressure information; Determining whether the first pressure information is greater than a preset first pressure threshold; If yes, controlling the working state of the pressure relief valve according to the first pressure information; Determining a first air volume upper limit threshold according to the working state of the pressure relief valve; Acquiring first temperature information; Determining whether the first temperature information exceeds a preset standard temperature value; If yes, obtaining first air volume information and first cooling information according to the first temperature information and the standard temperature value; Determining whether the first air volume information exceeds the first air volume upper limit threshold; If yes, adjusting the first air volume information according to the first air volume information and the first air volume upper limit threshold; The first cooling information is set according to the first air volume upper limit threshold.

2. A BMS mid-end security protection method according to claim 1, characterized in that: The controlling the working state of the pressure relief valve according to the first pressure information is specifically: According to a preset first time period, first pressure information is collected and recorded to obtain a first pressure sequence; determining first slope information according to the first pressure sequence; Obtaining pressure release parameter information according to the first slope information; The working state of the pressure relief valve is controlled according to the pressure relief parameter information.

3. A BMS mid-end security protection method according to claim 1, characterized in that: The first air volume upper limit threshold is determined according to the working state of the pressure relief valve, specifically: Obtaining first slope information; Determining whether the first slope information exceeds a preset first slope threshold; If so, the air volume threshold table selects the first air volume corresponding table; If not, the air volume threshold table selects the second air volume corresponding table; Get decompression parameter information; A first air volume upper limit threshold is determined according to the pressure relief parameter information and the air volume threshold table.

4. A BMS mid-end security protection method according to claim 1, characterized in that: The obtaining of the first air volume information and the first cooling information according to the first temperature information and the standard temperature value is specifically: Collecting first temperature information according to a preset first time period; Calculate the difference between the first temperature information and the standard temperature value to obtain first temperature deviation information; Obtaining a first proportional control amount, a first integral control amount, and a first differential control amount according to the first temperature deviation information and a set first control weight; Obtaining a first air volume control amount according to the first proportional control amount, the first integral control amount and the first differential control amount; The first air volume information is updated according to the first air volume control amount.

5. A BMS mid-end security protection method according to claim 1, characterized in that: The obtaining of the first air volume information and the first cooling information according to the first temperature information and the standard temperature value is specifically: Collecting first temperature information according to a preset second time period; Calculate the difference between the first temperature information and the standard temperature value to obtain first temperature deviation information; Obtaining a second proportional control amount and a second integral control amount according to the first temperature deviation information and a set second control weight; Obtaining a first refrigeration control amount according to the second proportional control amount and the second integral control amount; The first refrigeration information is updated according to the first refrigeration control amount.

6. A BMS mid-end security protection method according to claim 1, characterized in that: The adjusting the first cooling information according to the first air volume information and the first air volume upper limit threshold is specifically: Calculating a difference between the first air volume information and the first air volume upper limit threshold to obtain first air volume deviation information; determining a first cooling adjustment amount according to the first air volume deviation information; The first refrigeration information is adjusted according to the first refrigeration adjustment amount.

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