Battery module, control method of battery module, electric vehicle and power equipment

Abstract

The control method of the battery module is applied to the battery module, the battery module comprises a plurality of battery packs, a power switch, a sampling circuit and a controller, the power switch comprises a first switch, the controller is respectively coupled with the first switch and the sampling circuit, and the plurality of battery packs output electric energy through the first switch. When the controller controls the plurality of battery packs to discharge, a PWM signal with a set duty ratio can be sent to the first switch of the power switch. When the battery module supplies power to the capacitive load, the output voltage of the output port is partially increased in each switching period, so that the output voltage of the output port can be superposed to a relatively large voltage. And when the battery module is short-circuited, the output voltage of the output port is very small or zero. The processor can distinguish the short circuit of the battery module or the power supply of the battery module to the capacitive load according to whether the output voltage of the output port is greater than the set voltage, so that the power supply of the battery module to the capacitive load is realized.

Description

Battery module, battery module control method, electric vehicle, and power equipment Technical Field

[0001] The present invention relates to the technical field of battery management, and in particular to a battery module, a control method for a battery module, an electric vehicle, and electric power equipment. Background Art

[0002] With the development of new energy technologies, battery modules are increasingly being installed in power equipment. Battery modules can serve as either the primary or backup power source for these devices. A battery module typically consists of multiple cell packs and a battery management system (BMS). The BMS collects the total voltage and current of the battery pack and controls the connection and disconnection of the charging and discharging circuits.

[0003] In the prior art, when a battery module is charging or discharging, if the charging or discharging current is too high, the battery module triggers the overcurrent protection function, resulting in no external output and a power loss to the downstream load. When the battery module is powering a capacitive load, the voltage of the capacitor of the capacitive load cannot change suddenly at the moment of charging. This is equivalent to short-circuiting the battery module, causing the current of the battery module to suddenly increase, resulting in the battery module being unable to power the capacitive load.

[0004] Summary of the Invention

[0005] To address the aforementioned issues, embodiments of the present application provide a battery module that, when discharging multiple battery packs, can send a PWM signal with a set duty cycle to a power switch. Based on whether the output voltage of the battery module is greater than the set voltage, the module can distinguish whether the battery module is short-circuited or is supplying power to a capacitive load, thereby enabling the battery module to supply power to the capacitive load. Furthermore, embodiments of a control method for a battery module, an electric vehicle, and an electric power device corresponding to the battery module are provided.

[0006] To this end, the following technical solutions are adopted in the embodiments of the present application:

[0007] In a first aspect, an embodiment of the present application provides a battery module, characterized in that it includes: multiple battery packs, an output port, electrically connected to a load, for allowing the battery module to provide electrical energy to the load; a power switch, coupled between the multiple battery packs and the output port, for controlling the multiple battery packs to transfer electrical energy to the output port; a sampling circuit, coupled to the output port, for collecting the output voltage of the output port; a controller, for sending a PWM signal with a set duty cycle to the power switch, wherein the PWM signal is used to control the power switch to be in an on state; the controller is also used to receive the output voltage collected by the sampling circuit, and in response to the output voltage being not less than a set voltage, determine that the load powered by the battery module is a capacitive load.

[0008] In this embodiment, the controller can send a PWM signal with a set duty cycle to the power switch when controlling the discharge of multiple battery packs. When the battery module is powering a capacitive load, the output voltage at the output port increases by a certain amount during each switching cycle, allowing the output voltage at the output port to be superimposed on a larger voltage. If the battery module is short-circuited, the output voltage at the output port is very low or zero. The processor can distinguish whether the battery module is short-circuited or powering a capacitive load based on whether the output voltage at the output port is greater than the set voltage, thereby enabling the battery module to power the capacitive load.

[0009] In one embodiment, the controller is further used to send a full-duty cycle PWM signal to the power switch; and receive the output voltage collected by the sampling circuit, and in response to the output voltage being less than the total voltage of the multiple battery packs, determine that the load powered by the battery module is a capacitive load or the battery module is short-circuited.

[0010] In this embodiment, before the battery module supplies power to the load, the controller can detect the load type. The controller repeatedly sends full-duty PWM signals to the power switch to detect the output voltage at the output port. When the output voltage of the output port equals the total voltage of the multiple battery packs, the load powered by the battery module is non-capacitive. When the output voltage of the battery module is less than the total voltage of the multiple battery packs, the load powered by the battery module is capacitive or the battery module is short-circuited. By detecting the load type, the controller executes different control logic for different load types, thereby improving the control efficiency of the battery module.

[0011] In one embodiment, the controller is further configured to delay sending a full-duty cycle PWM signal to the power switch for a set time, wherein the set time is the time for the controller to start discharging the multiple battery packs.

[0012] In this embodiment, the controller controls the battery pack's discharge by activating components such as the DC / DC converter, PCB, and transformer. The battery module sends a PWM signal to the power switch after a set delay after initiating discharge, preventing the controller from detecting errors.

[0013] In one embodiment, the controller is further configured to send a PWM signal with a stepped duty cycle to the power switch in response to the output voltage being not less than a set voltage; the stepped duty cycle being a variable duty cycle from the set duty cycle increasing to the full duty cycle; receive the output voltage collected by the sampling circuit, and send a PWM signal with a full duty cycle to the power switch in response to the output voltage being equal to the total voltage of the multiple battery packs.

[0014] In this embodiment, when the controller determines that the load powered by the battery module is capacitive, the voltage at the output port may not reach the total voltage of the multiple battery packs. The controller increases the duty cycle of the PWM signal from the set duty cycle to the full duty cycle, allowing the output port to quickly increase to the total voltage of the multiple battery packs, allowing the battery module to normally power the capacitive load.

[0015] In one embodiment, the set duty cycle is a stepped duty cycle.

[0016] In this embodiment, each time the duty cycle of the PWM signal increases by a set duty cycle, the output voltage at the output port increases in magnitude. When the battery module is powering a capacitive load, the time it takes for the output voltage at the output port to reach the set voltage is shortened. This reduces the time the controller takes to send the PWM signal, lowering the risk of damage to other components in the battery module and lowering electrical and thermal performance requirements.

[0017] In one embodiment, the step duty cycle is a variable duty cycle that increases a set duty cycle at every interval of at least one switching cycle; wherein the value of the set duty cycle increases continuously each time.

[0018] In this embodiment, as the duty cycle of the PWM signal increases by the set duty cycle value, the output voltage at the output port increases further. When the battery module is powering a capacitive load, the time it takes for the output voltage at the output port to reach the set voltage can be further shortened. This can reduce the time the controller takes to send the PWM signal, reduce the risk of damage to other components in the battery module, and lower electrical and thermal performance requirements.

[0019] In one embodiment, the controller is further used to send a full-duty cycle PWM signal to the power switch and receive the output voltage collected by the sampling circuit; in response to the output voltage being not less than a set voltage, determine that the load powered by the battery module is a capacitive load; in response to the output voltage being less than the set voltage, determine that the battery module is short-circuited.

[0020] In this embodiment, when the battery module is powering a capacitive load with a relatively large capacitance, the controller outputs a full duty cycle. If the output voltage of the output port reaches a set voltage as the duty cycle of the PWM signal increases, the controller distinguishes between a battery module short circuit and a battery module powering a relatively large capacitive load.

[0021] In one embodiment, the controller is further configured to stop sending a PWM signal to the power switch in response to a short circuit of the battery module.

[0022] In this embodiment, when the controller determines that the battery module is short-circuited, it stops sending the PWM signal to prevent the battery module short-circuit from causing damage to other devices.

[0023] In a second aspect, an embodiment of the present application provides a control method for a battery module, which is applied to a battery module, wherein the battery module includes multiple battery packs, an output port, a power switch, a sampling circuit and a controller; the power switch is coupled between the multiple battery packs and the output port; the sampling circuit is coupled to the output port; the controller is coupled to the power switch and the sampling circuit, respectively; the method is executed by the controller, including: controlling the multiple battery packs to discharge; sending a PWM signal with a set duty cycle to the power switch; the PWM signal is used to control the power switch to be in an on state; receiving the output voltage collected by the sampling circuit, and in response to the output voltage being not less than the set voltage, determining that the load powered by the battery module is a capacitive load.

[0024] In one embodiment, before sending a PWM signal with a set duty cycle to the power switch, the method further includes: sending a PWM signal with a full duty cycle to the power switch; receiving an output voltage collected by the sampling circuit, and in response to the output voltage being less than the total voltage of the multiple battery packs, determining that the load powered by the battery module is a capacitive load or that the battery module is short-circuited.

[0025] In one embodiment, before sending the full-duty cycle PWM signal to the power switch, the method further includes: delaying the sending of the full-duty cycle PWM signal to the power switch for a set time, wherein the set time is the time for the controller to start the multiple battery packs to discharge.

[0026] In one embodiment, the set duty cycle is a fixed value, and the method further includes: in response to the output voltage being not less than the set voltage, sending a PWM signal with a stepped duty cycle to the power switch; the stepped duty cycle is a variable duty cycle from the set duty cycle increasing to the full duty cycle; receiving the output voltage collected by the sampling circuit, and in response to the output voltage being equal to the total voltage of the multiple battery packs, sending a PWM signal with a full duty cycle to the power switch.

[0027] In one embodiment, the set duty cycle is a stepped duty cycle.

[0028] In one embodiment, the step duty cycle is a variable duty cycle that increases a set duty cycle at every interval of at least one switching cycle; wherein the value of the set duty cycle increases continuously each time.

[0029] In one embodiment, the method further includes: sending a full-duty cycle PWM signal to the power switch and receiving an output voltage collected by the sampling circuit; in response to the output voltage being not less than a set voltage, determining that the load powered by the battery module is a capacitive load; and in response to the output voltage being less than the set voltage, determining that the battery module is short-circuited.

[0030] In one embodiment, the method further includes: in response to a short circuit of the battery module, stopping sending a PWM signal to the power switch.

[0031] In a third aspect, an embodiment of the present application provides an electric vehicle, comprising: at least one power-consuming device, and a backup power device electrically connected to the at least one power-consuming device; the backup power device comprises a power switch, for controlling the backup power device to provide electrical energy to the at least one power-consuming device; the backup power device is configured to send a PWM signal with a set duty cycle to the power switch, wherein the PWM signal is configured to control the power switch to be in an on state; the backup power device is further configured to detect an output voltage, and in response to the output voltage being not less than a set voltage, determine that the load powered by the backup power device is a capacitive load.

[0032] In one embodiment, the backup power device is further used to send a PWM signal with a stepped duty cycle to the power switch in response to the output voltage being not less than a set voltage; the stepped duty cycle is a changing duty cycle from the set duty cycle increasing to the full duty cycle; detect the output voltage, and send a PWM signal with a full duty cycle to the power switch in response to the output voltage being equal to the total voltage of the backup power device.

[0033] In one embodiment, the set duty cycle is a stepped duty cycle.

[0034] In one embodiment, the backup power device is further used to send a full-duty cycle PWM signal to the power switch and detect the output voltage; in response to the output voltage being not less than a set voltage, it is determined that the electrical device powered by the backup power device is a capacitive load; in response to the output voltage being less than the set voltage, it is determined that the backup power device is short-circuited.

[0035] In a fourth aspect, an embodiment of the present application provides an electric power device, comprising: at least one electronic component and at least one battery module, each electrically connected to the at least one electronic component; the battery module comprises a power switch, for controlling the battery module to provide electrical energy to the at least one electronic component; the battery module is used to send a PWM signal with a set duty cycle to the power switch, wherein the PWM signal is used to control the power switch to be in an on state; the battery module is also used to detect the output voltage, and in response to the output voltage being not less than the set voltage, determines that the load powered by the battery module is a capacitive load.

[0036] In one embodiment, a PWM signal of a ratio; the step duty cycle is a changing duty cycle from the set duty cycle to the full duty cycle; the output voltage is detected, and in response to the output voltage being equal to the total voltage of the battery module, a full duty cycle PWM signal is sent to the power switch.

[0037] In one embodiment, the set duty cycle is a stepped duty cycle.

[0038] In one embodiment, the battery module is further used to send a full-duty cycle PWM signal to the power switch and detect the output voltage; in response to the output voltage being not less than a set voltage, it is determined that the electronic component powered by the battery module is a capacitive load; in response to the output voltage being less than the set voltage, it is determined that the battery module is short-circuited. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The following is a brief introduction to the drawings required for describing the embodiments or prior art.

[0040] FIG1 is a schematic diagram of the architecture of a BMS in the prior art;

[0041] FIG2 is a schematic diagram of the architecture of an electric power device provided in an embodiment of the present application;

[0042] FIG3 is a schematic diagram of the architecture of a BMS provided in an embodiment of the present application;

[0043] FIG4 is a schematic diagram showing the relationship between a PWM signal, time, and output voltage for a controller to identify a capacitive load or a short circuit, provided in an embodiment of the present application;

[0044] FIG5 is a schematic diagram showing the relationship between a PWM signal, time, and output voltage for a controller to identify a capacitive load or a short circuit, provided in an embodiment of the present application;

[0045] FIG6 is a schematic diagram showing the relationship between a PWM signal, time, and output voltage for a controller to identify a capacitive load or a short circuit, provided in an embodiment of the present application;

[0046] FIG7 is a flow chart of a method for controlling a battery module provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0048] In the description of this application, the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting this application.

[0049] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, a conflicting connection or an integrated connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0050] In the description of this application, the term "and / or" is used to describe an association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The symbol " / " herein indicates that the associated objects are in an "or" relationship, for example, A / B means either A or B.

[0051] In the description of this application, the terms "first" and "second" are used to distinguish different objects rather than to describe a specific order of objects. For example, "first response message" and "second response message" are used to distinguish different response messages rather than to describe a specific order of response messages.

[0052] In the embodiments of this application, words such as "in one embodiment" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described in the embodiments of this application as "in one embodiment" or "for example" should not be interpreted as being more preferred or advantageous over other embodiments or designs. Rather, the use of words such as "in one embodiment" or "for example" is intended to present the relevant concepts in a concrete manner.

[0053] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0054] Figure 1 is a schematic diagram of the architecture of a prior art battery management system (BMS). As shown in Figure 1, BMS 10 includes a charging current limiting circuit 11 and a power switch 12. These circuits are connected in parallel to multiple battery packs in a battery module. The power switch 12 includes a first switch Q1 and a second switch Q2. The first and second switches Q1 and Q2 are connected in series.

[0055] The first switch Q1 and the second switch Q2 of the power switch 12 are generally composed of a metal-oxide-semiconductor field-effect transistor (MOSFET) (referred to as "MOS transistor") and a body diode connected in parallel. The body diode of the first switch Q1 is in opposite direction to the body diode of the second switch Q2.

[0056] When charging the battery module, the BMS 10 monitors the charging voltage. If the BMS 10 detects a significant voltage difference, it turns on the charging current limiting circuit 11 and turns off the power switch 12. External power can flow through the charging current limiting circuit 11 to power the multiple battery packs in the battery module. The charging current limiting circuit 11 allows high current within a set range to flow, allowing the high external current to power the multiple battery packs in the battery module.

[0057] When the BMS 10 detects a relatively small charging voltage difference, it disconnects the charging current limiting circuit 11 and turns on the first switch Q1 and the second switch Q2 of the power switch 12. The external power supply can then pass a high current through the second switch Q2 and the first switch Q1 to power the multiple battery packs in the battery module.

[0058] When the battery module is discharging, the BMS 10 can disconnect the charging current limiting circuit 11 and turn on both the first switch Q1 and the first switch Q2 of the power switch 12. The multiple battery packs in the battery module can provide power to the load through the first switch Q1 and the second switch Q2.

[0059] When a battery module short-circuits, the discharge current is excessive, triggering the overcurrent protection function, resulting in no output and potentially damaging the battery pack. To prevent the battery module from outputting excessive current, the BMS 10 can control the MOS transistors of the first switch Q1 or Q2 to slowly start and monitor the output current of the battery module. If the BMS 10 detects excessive output current, it controls the MOS transistor of the first switch Q1 to stop starting, preventing damage to the battery module.

[0060] However, when the battery module is powering a capacitive load, the voltage of the capacitive load capacitor cannot increase suddenly during the slow startup of the power switch 12. This is equivalent to the capacitive load capacitor short-circuiting the battery module, causing the BMS 10 to detect a large current in the battery module. Therefore, when the power switch 12 is slowly turned on, the BMS 10 cannot distinguish between a battery module short-circuit and the battery module powering a capacitive load, resulting in the battery module being unable to power the capacitive load.

[0061] In order to solve the problem that existing battery modules cannot power capacitive loads, the existing technology proposes two solutions, namely:

[0062] The first method is to increase the short-circuit current threshold. The BMS 10 identifies short circuits by increasing the current threshold that triggers short-circuit protection. However, this method does not allow the BMS 10 to distinguish between a battery module short circuit and a battery module powering a capacitive load. Moreover, increasing the short-circuit current threshold by the BMS 10 delays the occurrence of a battery module short circuit. When a battery module short circuits, the risk of damage to the battery pack increases.

[0063] The second method is to combine a counting unit with a short-circuit delay time. Within the short-circuit delay time, if the number of times counted by the counting unit exceeds the preset number threshold of the short-circuit current preset value, the BMS 10 will identify it as a true short circuit. However, the BMS 10 increases the risk of device damage and increases the electrical and thermal stress requirements of the device. The BMS 10 cannot adaptively adjust the startup time with a capacitive load according to the size of the capacitive load. Moreover, when the capacitance of the capacitive load is relatively large, the BMS 10 may still reach the preset number threshold and be identified as a true short circuit, so it cannot accurately identify the capacitive load.

[0064] In order to solve the defect that the existing battery module cannot supply power to capacitive loads, the embodiments of the present application provide an electric power device, an electric vehicle, a battery module and a control method of the battery module.

[0065] Figure 2 is a schematic diagram of the architecture of an electric power device provided in an embodiment of the present application. As shown in Figure 2, the electric power device includes a battery module 20 and an electronic component 30. The battery module 20 is electrically connected to the electronic component 30. The battery module 20 includes a BMS 21, multiple battery packs 22 and an output port 23. When the electronic component 30 is a capacitive load, multiple capacitors 31 are arranged inside the electronic component 30. The output port 23 is arranged on the outer surface of the battery module 20. Multiple battery packs 22 are electrically connected to the output port 23 through the BMS 21. The output port 23 can be electrically connected to the electronic component 30 through a wire, so that the battery module 20 can be electrically connected to the capacitor 31 of the electronic component 30. The electronic component 30 can be an electrical device of the electric power device, such as a chip, a circuit board, a processor, a memory and other devices. The electric power device can be an electric vehicle, a base station, an outdoor cabinet and other equipment.

[0066] In one embodiment, the number of battery assemblies 20 in the power device can be one or more. The number of electronic assemblies 30 in the power device can be one or more. Each battery assembly 20 can be electrically connected to one or more electronic assemblies 30.

[0067] In the present application, the power device includes at least one electronic component and at least one battery assembly. The at least one battery module is electrically connected to the at least one electronic component. The battery module includes a power switch. The power switch controls the battery module to provide power to the electronic component. The battery module is configured to send a pulse width modulation (PWM) signal with a set duty cycle to the power switch. The PWM signal is used to control the power switch to be in an on state. The battery module is also configured to detect an output voltage and, in response to the output voltage being not less than a set voltage, determine that the load powered by the battery module is a capacitive load.

[0068] In one embodiment, the power device is an electric vehicle. The electric vehicle includes at least one power-consuming device and a backup power device. The backup power device and the at least one power-consuming device. The backup power device includes a power switch. The power switch controls the backup power device to provide power to the at least one power-consuming device. The backup power device is configured to send a PWM signal with a set duty cycle to the power switch. The PWM signal is configured to control the power switch to be in an on state. The backup power device is further configured to detect the output voltage and, in response to the output voltage being no less than a set voltage, determine that the load powered by the battery module is a capacitive load. In other embodiments, the power-consuming device may be a motor, a lighting system, a refrigeration system, etc.

[0069] FIG3 is a schematic diagram of the architecture of a BMS provided in an embodiment of the present application. As shown in FIG3 , the BMS 21 includes a power switch 211 , a sampling circuit 212 , and a controller 213 . The controller 213 is electrically connected to the power switch 211 and the sampling circuit 212 , respectively.

[0070] The power switch 211 is used to control the multiple battery packs 22 in the battery module 20 to provide power to the electronic component 30. In the present application, the power switch 211 may include a first switch Q1 and a second switch Q2. The first switch Q1 and the second switch Q2 are connected in series. The first switch Q1 and the second switch Q2 may both be composed of devices such as MOS transistors, insulated gate bipolar transistors (IGBTs), and body diodes.

[0071] The sampling circuit 212 is electrically connected to the output port 23 , and is used to collect the voltage value of the DC power at the output port 23 and send the voltage value to the controller 213 .

[0072] The controller 213 can be a microcontroller unit (MCU), a digital signal processing (DSP) unit, a field programmable gate array (FPGA), or other control device. The controller 213 can receive the voltage value from the sampling circuit 212. The controller 213 can send a PWM signal to the power switch 211 to control the first switch Q1 and / or the second switch Q2 of the power switch 211 to be in an on or off state, thereby distinguishing between a short circuit in the battery module 20 and powering a capacitive load.

[0073] When the controller 213 controls the discharge of the battery pack 22, it must activate components such as a direct current / direct current (DC / DC) converter, a printed circuit board (PCB), and a transformer to enable the battery pack 22 to discharge. When the controller 213 initiates the discharge of the battery pack 22, it delays for a first set time before sending a PWM signal to the power switch 211. The battery module 21 delays the set time after initiating discharge to power the electronic component 30, preventing the controller 213 from detecting errors. The first set time is the time it takes for the controller 213 to initiate the discharge of multiple battery packs.

[0074] After the controller 213 determines that the battery module 20 has completed the discharge startup process, it sends a PWM signal to the second switch Q2 of the power switch 211. The PWM signal sent by the controller 213 is a full-duty PWM signal. That is, during one switching cycle, the duration t of the PWM signal sent by the controller 213 is equal to one switching cycle T. The controller 213 sends the full-duty PWM signal to the second switch Q2, ensuring that the second switch Q2 is always in the switching state.

[0075] The controller 213 can send a full-duty cycle PWM signal to the first switch Q1 of the power switch 211 multiple times within the second set time. After receiving the PWM signal, the first switch Q1 of the power switch 211 can turn on the power switch 211. At this time, the battery module 20 can provide power to the load.

[0076] When the controller 213 sends a PWM signal to the first switch Q1 of the power switch 211, the controller 213 can receive the sampled voltage Vbus from the output port of the battery module collected by the sampling circuit 212 in real time, record and store the sampled voltage Vbus. After receiving the sampled voltage Vbus, the controller 213 determines whether the sampled voltage Vbus is equal to the voltage Vbat of the multiple battery packs 21 of the battery module 20.

[0077] In one embodiment, when the controller 213 determines that the sampled voltage Vbus is equal to the voltage Vbat of the multiple battery packs 21 of the battery module 20, the controller 213 may consider that the battery module 20 is not short-circuited, or that the load powered by the battery module 20 is other non-capacitive load.

[0078] In one embodiment, when the sampled voltage Vbus is less than the voltage Vbat of the multiple battery packs 21 of the battery module 20, the controller 213 may deem the battery module 20 short-circuited or the battery module 20 powering a capacitive load, triggering the overcurrent protection function. The controller 213 stops sending PWM signals to the first switch Q1 of the power switch 211, shutting down the drive, and stopping the battery module 20 from outputting power.

[0079] After a period of time, the controller 213 again sends a full-duty cycle PWM signal to the first switch Q1 of the power switch 211, and receives the sampled voltage Vbus from the output port of the battery module collected by the sampling circuit 212. The controller 213 again detects whether the battery module 20 has triggered the overcurrent protection function. This process continues in this manner until the controller 213 completes multiple detections of whether the battery module 20 has triggered the overcurrent protection function. In the present application, when the controller 213 sends PWM signals multiple times and the overcurrent protection function is triggered, the controller 213 can determine that the battery module 20 is short-circuited or that the load powered by the battery module 20 is a capacitive load.

[0080] When the controller 213 distinguishes between a short circuit in the battery module 20 and a capacitive load powered by the battery module 20, the controller 213 sends a PWM signal with a set duty cycle to the first switch Q1 of the power switch 211. The set duty cycle refers to the ratio of the duration Ton of the PWM signal sent by the controller 213 to the first switch Q1 of the power switch 211 to the switching period T during one switching cycle.

[0081] The PWM signal used to set the duty cycle is not a full-duty PWM signal; instead, it is an intermittent pulse signal. When the battery module supplies power to a capacitive load, the capacitance of the capacitive load increases slightly with each switching cycle, causing the output voltage Vbus at output port 23 to increase slightly with each switching cycle. This allows the output voltage at output port 23 to gradually increase to a higher voltage. When the battery module 20 is short-circuited, the output voltage Vbus at output port 23 remains very low or zero.

[0082] When the battery module 20 supplies power to a capacitive load, the output voltage of the output port 23 gradually increases. In one embodiment, during the first switching cycle when the controller 213 sends a PWM signal to the first switch Q1 of the power switch 211, after the controller 213 controls the power switch 211 to be in the on state, the output voltage of the output port 23 increases by ΔV. In the second switching cycle, after the controller 213 controls the power switch 211 to be in the on state, the output voltage of the output port 23 increases again by ΔV, i.e., 2ΔV, compared to the first switching cycle. Similarly, in the Nth switching cycle, after the controller 213 controls the power switch 211 to be in the on state, the output voltage of the output port 23 is NΔV, where N is a positive integer greater than or equal to 2.

[0083] In the present application, during a switching cycle, when the capacitance of the capacitive load is relatively large, the voltage ΔV by which the output voltage of the output port 23 rises each time is relatively small, and the output voltage of the output port 23 rises at a relatively slow rate. When the capacitance of the capacitive load is relatively small, the voltage ΔV by which the output voltage of the output port 23 rises each time is relatively large, and the output voltage of the output port 23 rises at a relatively fast rate.

[0084] In the present application, the controller 213 can send a PWM signal with a set duty cycle to the first switch Q1 of the power switch 211 within a third set time, thereby preventing the first switch Q1 of the power switch 211 from being in a constant on / off state. The third set time is the time period during which the controller 213 identifies the battery module 20 as a capacitive load with a relatively small capacitance.

[0085] When the controller 213 sends a PWM signal to the first switch Q1 of the power switch 211, the controller 213 collects the output voltage Vbus of the output port 23 in real time through the sampling circuit 212. The controller 213 can determine whether the load powered by the battery module 20 is a capacitive load based on whether the output voltage Vbus of the output port 23 is less than a set voltage. The set voltage refers to the output voltage of the output port 23 at the moment the battery module 20 is supplying power to the capacitive load. In other embodiments, the set voltage can be the lowest value of the output voltage of the battery module 20 at the moment it is supplying power to the capacitive load.

[0086] When the controller 213 detects that the output voltage Vbus of the output port 23 is not less than the set voltage within the third set time, the controller 213 may determine that the load powered by the battery module 20 is a capacitive load. In other embodiments, when the controller 213 determines that the load powered by the battery module 20 is a capacitive load, the controller 213 may stop sending a PWM signal with a set duty cycle to the first switch Q1 of the power switch 211, thereby reducing the conduction time of the battery module 20 and reducing the risk of burning out the battery module 20.

[0087] If the controller 213 detects that the output voltage Vbus of the output port 23 is less than the set voltage within the third set time, the controller 213 may determine that the battery module 20 is short-circuited or that the capacitive load powered by the battery module 20 has a relatively large capacitance. When the capacitive load has a relatively large capacitance, the output voltage of the output port 23 rises more slowly, and the output voltage of the output port 23 may be less than the set voltage within the third set time. In one embodiment, if the controller 213 detects that the output voltage Vbus of the output port 23 is not less than the voltage Vmin within the third set time, the controller 213 may identify that the battery module 20 is powering a capacitive load with a relatively large capacitance.

[0088] The duty cycle of the PWM signal sent by the controller 213 within the third set time can be a fixed value or a step duty cycle. The step duty cycle can be continuously increased from the set duty cycle to the full duty cycle. In the present application, in the first switching cycle within the third set time, the duty cycle of the PWM signal is D1. In the second switching cycle within the third set time, the duty cycle of the PWM signal is increased by a set duty cycle on the basis of the first switching cycle, and the duty cycle of the PWM signal is recorded as D1+△D1. In the third switching cycle within the third set time, the duty cycle of the PWM signal is increased by a set duty cycle on the basis of the second switching cycle, and the duty cycle of the PWM signal is recorded as D1+2△D1. Similarly, in the Mth switching cycle within the third set time, the duty cycle of the PWM signal is D1+(M-1)△D1. M is a positive integer greater than or equal to 2.

[0089] In one embodiment, the duty cycle of the PWM signal may be increased by a set duty cycle ΔD1 after a plurality of switching cycles.

[0090] In one embodiment, the duty cycle of the PWM signal may be increased by a set duty cycle ΔD1 after different switching cycles.

[0091] In one embodiment, the value of the set duty cycle for each increase in the duty cycle of the PWM signal may be different.

[0092] In the embodiment of the present application, each time the duty cycle of the PWM signal increases by a set duty cycle, the output voltage of the output port 23 increases by a larger amount. When the battery module 20 is powering a capacitive load, the time it takes for the output voltage Vbus of the output port 23 to reach the set voltage is shortened. This can reduce the time it takes for the controller 213 to send the PWM signal, lower the risk of damage to other components of the battery module 20, and reduce electrical and thermal performance requirements.

[0093] Compared with a fixed duty cycle, the advantage of a step duty cycle is that when the battery module 20 supplies power to a capacitive load with a relatively large capacitance, the output voltage Vbus of the output port 23 can be increased to the set voltage within the third set time, which can improve the accuracy of the controller 213 in distinguishing between a short circuit in the battery module 20 and a capacitive load powered by the battery module 20.

[0094] When the duty cycle of the PWM signal sent by the controller 213 within the third set time is a fixed value, the controller 213 may again send a PWM signal with a stepped duty cycle to the first switch Q1 of the power switch 211 after the third set time. The stepped duty cycle may continuously increase from the set duty cycle to the full duty cycle. In the present application, in the first switching cycle after the third set time, the duty cycle of the PWM signal is D2. In the second switching cycle after the third set time, the duty cycle of the PWM signal is increased by a set duty cycle based on the first switching cycle, and the duty cycle of the PWM signal is D2+ΔD2. In the third switching cycle after the third set time, the duty cycle of the PWM signal is increased by a set duty cycle based on the second switching cycle, and the duty cycle of the PWM signal is D2+2ΔD2. This process continues in this manner until the duty cycle of the PWM signal sent by the controller 213 reaches the full duty cycle. The time it takes for the PWM signal to increase from the set duty cycle to the full duty cycle is the fourth set time.

[0095] In one embodiment, the duty cycle of the PWM signal may be increased by a set duty cycle ΔD2 after a plurality of switching cycles.

[0096] In one embodiment, the duty cycle of the PWM signal may be increased by a set duty cycle ΔD2 after different switching cycles.

[0097] In one embodiment, the value of the set duty cycle for each increase in the duty cycle of the PWM signal may be different.

[0098] In the embodiment of the present application, when the battery module 20 is supplying power to a capacitive load with a relatively large capacitance, the controller 213 increases the duty cycle of the PWM signal from a set duty cycle to a full duty cycle. If the output voltage of the output port 23 reaches the set voltage during the increase in the duty cycle of the PWM signal, the controller 213 can distinguish in advance whether the battery module 20 is short-circuited or the load powered by the battery module 20 is a capacitive load with a relatively large capacitance, thereby reducing the risk of damage to other components of the battery module 20 and lowering the requirements for electrical and thermal performance.

[0099] When the controller 213 distinguishes between a short circuit in the battery module 20 and a capacitive load with a large capacitance, it can send a full-duty-cycle PWM signal to the first switch Q1 of the power switch 211. The controller 213 can send a full-duty-cycle PWM signal to the first switch Q1 of the power switch 211 during a fifth set time, thereby preventing the first switch Q1 of the power switch 211 from being permanently switched. The fifth set time is the period of time during which the controller 213 identifies the battery module 20 as a capacitive load with a large capacitance.

[0100] When the controller 213 sends a PWM signal to the first switch Q1 of the power switch 211 within the fifth set time, the controller 213 collects the output voltage of the output port 23 in real time through the sampling circuit 212. The controller 213 can determine whether the load powered by the battery module 20 is a capacitive load with a large capacitance based on whether the output voltage Vbus of the output port 23 is less than the set voltage.

[0101] In one embodiment, when the controller 213 detects that the output voltage Vbus of the output port 23 is not less than the set voltage within the fifth set time, the controller 213 may determine that the capacitance of the capacitive load powered by the battery module 20 is relatively large.

[0102] In one embodiment, when the controller 213 detects that the output voltage Vbus of the output port 23 is less than the set voltage within the fifth set time, the controller 213 may determine that the battery module 20 is short-circuited.

[0103] In an embodiment of the present application, the controller 213 controls the duty cycle and time of sending a PWM signal to the first switch Q1 of the power switch 211, thereby enabling identification of three situations in different time periods: the battery module 20 is supplying power to a capacitive load with a smaller capacitance, the battery module 20 is supplying power to a capacitive load with a larger capacitance, and the battery module 20 is short-circuited. For example, within the second set time, the controller 213 sends a full-duty-cycle PWM signal to the first switch Q1 of the power switch 211 multiple times. When the controller 213 sends the PWM signal multiple times and triggers overcurrent protection, the controller 213 can determine that the battery module 20 is short-circuited or that the load powered by the battery module 20 is a capacitive load.

[0104] For example, during the third set time, the controller 213 sends a PWM signal with a set duty cycle or a variable duty cycle to the first switch Q1 of the power switch 211. When the output voltage of the output port 23 is not less than the set voltage, the controller 213 may determine that the battery module 20 is supplying power to a capacitive load with a relatively small capacitance.

[0105] For example, during the fourth set time, the duty cycle of the PWM signal sent by the controller 213 to the first switch Q1 of the power switch 211 increases from the set duty cycle to the full duty cycle. When the output voltage of the output port 23 is not less than the set voltage, the controller 213 may determine that the battery module 20 is supplying power to a capacitive load with a large capacitance.

[0106] For example, during the fifth set time, the controller 213 sends a full-duty cycle PWM signal to the first switch Q1 of the power switch 211. When the output voltage of the output port 23 is not less than the set voltage, the controller 213 may determine that the battery module 20 is supplying power to a capacitive load with a large capacitance. When the output voltage of the output port 23 is less than the set voltage, the controller 213 may determine that the battery module 20 is short-circuited.

[0107] Controller 213 does not have a fixed slow-start time; it can adaptively adjust the slow-start time for capacitive loads of varying sizes, resulting in a faster slow-start process. Controller 213 also has a short-circuit detection function, enabling short-circuit detection and protection during the slow-start phase. This reduces the risk of damage to other components in the battery module 20 and lowers electrical and thermal performance requirements.

[0108] Figure 4 is a schematic diagram illustrating the relationship between PWM signals, time, and output voltage for a controller identifying a capacitive load, as provided in an embodiment of the present application. As shown in Figure 4 , during the time period t0-t1, the battery module 21 is in the startup initialization phase. During this phase, the controller 213 does not send a PWM signal to the first switch Q1 of the power switch 211. The time period t0-t1 is the aforementioned "first set time."

[0109] The t1-t2 time period is the capacitive load identification stage. After the battery module 20 completes the startup work of discharge, the controller 213 sends a PWM signal with a full duty cycle D to the first switch Q1 of the power switch 211. When the battery module 20 is short-circuited or the battery module 20 supplies power to a capacitive load, the port voltage of the battery module 20 is low or close to 0V. At this time, the controller 213 triggers the discharge overcurrent protection function, stops sending the PWM signal to the first switch Q1 of the power switch 211, and turns off the first switch Q1. Repeat the above operation again after δT2, and repeat it N times. It is then identified that the subsequent stage is a capacitive load or short circuit, and the sending of the full duty cycle PWM waveform is suspended. After standing for δT3, the next stage begins. Among them, the t1-t2 time period is the above-mentioned "second set time".

[0110] The t2-t3 time period is a fixed duty cycle stage. The controller 213 periodically sends a PWM signal with a set duty cycle Dinit to the first switch Q1 of the power switch 211 during the t2-t3 time period. When the battery module 20 is short-circuited, the output voltage Vbus of the output port 23 is basically 0V or less than the set voltage Vmin. The controller 213 detects the output voltage Vbus of the output port 23 at time δt4, stops the slow start, and completes the short circuit identification function. When the load powered by the battery module 20 is a capacitive load, the output voltage Vbus of the output port 23 increases by ΔV in each switching cycle. Among them, when the capacitance of the capacitive load is relatively large, the value of the ΔV increase of the output voltage Vbus of the output port 23 in each switching cycle is relatively small. The output voltage Vbus of the output port 23 is less than Vbat-δV during the t2-t3 time period. The controller 213 stops sending the PWM signal to the first switch Q1, and the slow start ends. When the capacitive load powered by battery module 20 has a relatively small capacitance, the output voltage Vbus of output port 23 increases by a relatively large amount (ΔV) during each switching cycle. Therefore, the output voltage Vbus of output port 23 is no less than Vbat-δV during the time period t2-t3. The battery module completes the slow start prematurely, adaptively adjusting the slow start time and entering the next time period. The time period t2-t3 is the aforementioned "third set time." Vbat-δV is the aforementioned "set voltage."

[0111] The time period t3-t4 is the full duty cycle stage. The controller 213 periodically sends a PWM signal with a full duty cycle D to the first switch Q1 of the power switch 211 during the time period t3-t4. The time period t3-t4 is the aforementioned "fifth set time".

[0112] In the embodiment of the present application, during the time period t2 - t3, when the output voltage Vbus of the output port 23 is not less than Vbat - δV during the time period t2 - t3, the controller 213 determines that the battery module 20 supplies power to a capacitive load, can enter the next stage in advance to give a full duty cycle, end the soft start, and can shorten the detection time. During the time period t2 - t4, when the output voltage Vbus of the output port 23 < Vmin, the controller 213 determines that the battery module 20 is short-circuited. The controller 213 can stop sending waves and end the soft start. If the set duty cycle Dinit is very small, when the battery module 20 is short-circuited, the controller 213 can suppress the short-circuit impact current flowing through the power switch 211.

[0113] Compared with the prior art, the controller 213 of the present application uses triggering the overcurrent protection for n discharges as the capacitive load identification flag. The controller 213 can not fix the soft start time, can adaptively adjust the time of the soft start process with capacitive loads of different sizes, and can make the soft start process faster. In addition, the controller 213 has a short-circuit identification function, can perform short-circuit identification and protection during the soft start stage, reduces the risk of damage to other components of the battery module 20, and reduces the requirements for electrical and thermal performance.

[0114] FIG. 5 is a schematic diagram of the relationship between the PWM signal, time, and output voltage for a controller to identify a capacitive load provided in the embodiment of the present application. As shown in FIG. 5, during the time period t0 - t1, the battery module 21 is in the start-up stage. The controller 213 does not send a PWM signal to the first switch Q1 of the power switch 211 during this stage. Among them, the time period t0 - t1 is the above-mentioned "first set time".

[0115] The time period t1 - t2 is the capacitive load identification stage. After the battery module 20 completes the start-up work of discharging, the controller 213 periodically sends a PWM signal with a full duty cycle D to the first switch Q1 of the power switch 211. When the battery module 20 is short-circuited or the battery module 20 supplies power to a capacitive load, the port voltage of the battery module 20 is relatively low or close to 0V. At this time, the controller 213 triggers the function of overcurrent protection for discharging, stops sending a PWM signal to the first switch Q1 of the power switch 211, and closes the first switch Q1. Repeat the above operation again after δT2. Repeat this N times, then it is identified that the subsequent stage is a capacitive load or a short circuit, pause sending the full duty cycle PWM waveform, and start the next stage after standing still for δT3. Among them, the time period t1 - t2 is the above-mentioned "second set time".

[0116] The time period from t2 to t3 is the step duty cycle stage. The controller 213 periodically sends PWM signals with different duty cycles Dinit to the first switch Q1 of the power switch 211 during the time period from t2 to t3. The duty cycle of the PWM signal sent by the controller 213 in each cycle is a different value, and the value of the duty cycle continuously increases. The duty cycle of the PWM signal increases from the set duty cycle to the full duty cycle. When the battery module 20 is short-circuited, the output voltage Vbus of the output port 23 is basically 0V or less than the set voltage Vmin. The controller 213 detects the output voltage Vbus of the output port 23 at the moment of δt4, stops the soft start, and completes the short-circuit identification function. When the load powered by the battery module 20 is a capacitive load, the output voltage Vbus of the output port 23 increases by △V in each switching cycle. Among them, when the capacitance value of the capacitive load is relatively large, the value of △V by which the output voltage Vbus of the output port 23 increases in each switching cycle is relatively small, and the output voltage Vbus of the output port 23 is less than Vbat - δV during the time period from t2 to t3. The controller 213 stops sending the PWM signal to the first switch Q1, and the soft start ends. When the capacitance value of the capacitive load powered by the battery module 20 is relatively small, the value of △V by which the output voltage Vbus of the output port 23 increases in each switching cycle is relatively large, and the output voltage Vbus of the output port 23 is not less than Vbat - δV during the time period from t2 to t3. The battery module completes the soft start in advance, realizes the adaptive adjustment of the soft start time, and enters the next time period. Among them, the time period from t2 to t3 is the above-mentioned "third set time". Vbat - δV is the above-mentioned "set voltage".

[0117] The time period from t3 to t4 is the full duty cycle stage. The controller 213 periodically sends PWM signals with a full duty cycle D to the first switch Q1 of the power switch 211 during the time period from t3 to t4. Among them, the time period from t3 to t4 is the above-mentioned "fifth set time". The value by which the duty cycle increases each time is the above-mentioned "set duty cycle".

[0118] In the embodiment of the present application, during the time period from t2 to t3, when the output voltage Vbus of the output port 23 is not less than Vbat - δV during the time period from t2 to t3, the controller 213 determines that the battery module 20 is supplying power to a capacitive load, can enter the next stage in advance to give a full duty cycle, and end the soft start, which can shorten the detection time. During the time period from t2 to t4, when the output voltage Vbus of the output port 23 < Vmin, the controller 213 determines that the battery module 20 is short-circuited. The controller 213 can stop sending waves and end the soft start. During the time period from t2 to t3, when the value by which the duty cycle increases each time continuously increases, the soft start time of the battery module 20 can be reduced.

[0119] Compared to the technical solution shown in FIG4 , when the duty cycle of the PWM signal sent by the controller 213 in each cycle is different and the duty cycle value continuously increases, the voltage value ΔV that the output voltage of the output port 23 increases in each cycle continuously. When the battery module 20 is powering a capacitive load, the time it takes for the output voltage Vbus of the output port 23 to reach Vbat-δV is shortened, which can reduce the time it takes for the controller 213 to send the PWM signal, reduce the risk of damage to other components of the battery module 20, and reduce the requirements for electrical and thermal performance. In addition, when the battery module 20 is powering a capacitive load with a relatively large capacitance, the output voltage Vbus of the output port 23 can be increased to Vbat-δV within the time period t2-t3, which can reduce the detection time of the battery module 20 powering a capacitive load with a relatively large capacitance, reduce the risk of damage to other components of the battery module 20, and reduce the requirements for electrical and thermal performance.

[0120] Figure 6 is a schematic diagram illustrating the relationship between PWM signals, time, and output voltage for a controller identifying a capacitive load, as provided in an embodiment of the present application. As shown in Figure 6 , during the time period t0-t1, the battery module 21 is in the startup phase. During this phase, the controller 213 does not send a PWM signal to the first switch Q1 of the power switch 211. The time period t0-t1 is the aforementioned "first set time."

[0121] The t1-t2 time period is the capacitive load identification stage. After the battery module 20 completes the startup work of discharge, the controller 213 periodically sends a PWM signal with a full duty cycle D to the first switch Q1 of the power switch 211. When the battery module 20 is short-circuited or the battery module 20 supplies power to a capacitive load, the port voltage of the battery module 20 is low or close to 0V. At this time, the controller 213 triggers the discharge overcurrent protection function, stops sending the PWM signal to the first switch Q1 of the power switch 211, and turns off the first switch Q1. Repeat the above operation again after δT2, and repeat it N times. It is then identified that the subsequent stage is a capacitive load or short circuit, and the sending of the full duty cycle PWM waveform is suspended. After standing for δT3, the next stage begins. Among them, the t1-t2 time period is the above-mentioned "second set time".

[0122] The t2-t3 time period is a fixed duty cycle stage. The controller 213 periodically sends a PWM signal with a set duty cycle Dinit to the first switch Q1 of the power switch 211 during the t2-t3 time period. When the battery module 20 is short-circuited, the output voltage Vbus of the output port 23 is basically 0V or less than the set voltage Vmin. The controller 213 detects the output voltage Vbus of the output port 23 at time δt4, stops the slow start, and completes the short circuit identification function. When the load powered by the battery module 20 is a capacitive load, the output voltage Vbus of the output port 23 increases by ΔV in each switching cycle. Among them, when the capacitance of the capacitive load is relatively large, the value of the ΔV increase of the output voltage Vbus of the output port 23 in each switching cycle is relatively small. The output voltage Vbus of the battery module 20 is less than Vbat-δV during the t2-t3 time period. The controller 213 stops sending the PWM signal to the first switch Q1, and the slow start ends. When the capacitive load powered by battery module 20 has a relatively small capacitance, the output voltage Vbus of output port 23 increases by a relatively large amount (ΔV) during each switching cycle. Therefore, the output voltage Vbus of output port 23 is no less than Vbat-δV during the time period t2-t3. The battery module completes the slow start prematurely, adaptively adjusting the slow start time and entering the next time period. The time period t2-t3 is the aforementioned "third set time." Vbat-δV is the aforementioned "set voltage."

[0123] The t3-t4 time period is the step-duty cycle stage. During the t3-t4 time period, the controller 213 periodically sends PWM signals with different duty cycles Dinit to the first switch Q1 of the power switch 211. The duty cycle of the PWM signal sent by the controller 213 in each cycle is a different value, and the value of the duty cycle continues to increase, and the duty cycle of the PWM signal increases from the set duty cycle to the full duty cycle. When the load powered by the battery module 20 is a capacitive load, the output voltage Vbus of the output port 23 increases significantly in each switching cycle, accelerating the completion of the slow start process. Among them, the t3-t4 time period is the above-mentioned "fourth set time". The value of each increase in the duty cycle is the above-mentioned "set duty cycle".

[0124] The time period t4-t5 is the full duty cycle stage. The controller 213 periodically sends a PWM signal with a full duty cycle D to the first switch Q1 of the power switch 211 during the time period t4-t5. The time period t4-t5 is the aforementioned "fifth set time".

[0125] In the embodiment of the present application, within the time period t2 - t4, when the output voltage Vbus of the output port 23 is not less than Vbat - δV within the time period t2 - t4, the controller 213 determines that the battery module 20 supplies power to a capacitive load, can stop wave generation, end the soft start, and can shorten the detection time. Within the time period t2 - t5, when the output voltage Vbus of the output port 23 < Vmin, the controller 213 determines that the battery module 20 is short - circuited. The controller 213 can stop wave generation and end the soft start.

[0126] In the embodiment of the present application, the processor 213 first uses a fixed duty cycle in the initial stage, and then gradually releases the duty cycle, which can suppress the short - circuit impact current when the load is truly short - circuited. In the scenario where the load is not short - circuited, the soft - start time can be shortened. Compared with the technical solution shown in FIG. 4, after the output voltage of the output port 23 satisfies the δV voltage difference condition, due to the gradual release of the duty cycle, the discharge current impact at time t3 is smaller.

[0127] Compared with the technical solution shown in FIG. 5, when the battery module 20 supplies power to a capacitive load with a relatively large capacitance value, the output voltage Vbus of the output port 23 can be increased to Vbat - δV within the time when the duty cycle of the PWM signal increases from the set duty cycle to the full duty cycle, which can distinguish between the short - circuit of the battery module 20 and the capacitive load with a relatively large capacitance value powered by the battery module 20, reduce the detection time for the battery module 20 to supply power to a capacitive load with a relatively large capacitance value, reduce the damage risk of other devices of the battery module 20, and reduce the requirements for electrical and thermal performance. In addition, when pre - charging the capacitive load in the fixed duty - cycle stage, the voltage difference between the battery voltage and the output port voltage of the lithium - ion product in the stepped duty - cycle stage is smaller, and the electrical stress is smaller.

[0128] FIG. 7 is a schematic flowchart of a control method for a battery module provided in the embodiment of the present application. As shown in FIG. 7, this control method is executed by the processor 213, and the specific implementation process is as follows:

[0129] Step S701, the controller 213 delays a set time and sends a PWM signal with a full duty cycle to the first switch Q1 of the power switch 211.

[0130] When the controller 213 controls the battery pack 22 to discharge, the controller 213 needs to call the discharge device to work to make the battery pack 22 discharge. When the controller 213 starts the battery pack 22 to discharge, after delaying the first set time, the controller 213 sends a PWM signal to the switch of the power switch 211. The battery module 21 supplies power to a capacitive load after delaying the set time after starting to discharge, avoiding incorrect detection by the controller 213.

[0131] After the controller 213 determines that the battery module 20 has completed the discharge startup process, it sends a full-duty cycle PWM signal to the second switch Q2 of the power switch 211, thereby keeping the second switch Q2 in the on state. The controller 213 may send a full-duty cycle PWM signal to the first switch Q1 of the power switch 211 multiple times within the second set time. After receiving the PWM signal, the first switch Q1 of the power switch 211 can turn the power switch 211 into the on state.

[0132] In step S702, the controller 213 detects whether the output voltage of the output port 23 is equal to the voltage of the multiple battery packs in the battery module 20 each time the PWM signal is transmitted. If the output voltage of the output port 23 is equal to the voltage of the multiple battery packs in the battery module 20, the controller 213 terminates the operation. If the output voltage of the output port 23 is not equal to the voltage of the multiple battery packs in the battery module 20, step S703 is executed.

[0133] When the controller 213 sends a PWM signal to the first switch Q1 of the power switch 211, the controller 213 can receive the sampled voltage Vbus of the output port 23 collected by the sampling circuit 212 in real time. After receiving the sampled voltage Vbus, the controller 213 determines whether the sampled voltage Vbus is equal to the voltage Vbat of the multiple battery packs 21 of the battery module 20. In one embodiment, when the controller 213 determines that the sampled voltage Vbus is equal to the voltage Vbat of the multiple battery packs 21 of the battery module 20, the controller 213 can assume that the battery module 20 is not short-circuited, or that the load powered by the battery module 20 is other non-capacitive load. In one embodiment, when the sampled voltage Vbus is less than the voltage Vbat of the multiple battery packs 21 of the battery module 20, the controller 213 can assume that the battery module 20 is short-circuited or that the battery module 20 is powering a capacitive load, triggering the overcurrent protection function. The controller 213 stops sending the PWM signal to the first switch Q1 of the power switch 211 and turns off the drive, so that the battery module 20 stops outputting electrical energy.

[0134] After a period of time, the controller 213 again sends a full-duty PWM signal to the first switch Q1 of the power switch 211 and receives the sampled voltage Vbus from the output port 23 collected by the sampling circuit 212. The controller 213 again detects whether the battery module 20 has triggered the overcurrent protection function. This process continues until the controller 213 completes multiple detections of whether the battery module 20 has triggered the overcurrent protection function. If the controller 213 sends the PWM signal multiple times and the overcurrent protection function is triggered, the controller 213 can determine that the battery module 20 is short-circuited or that the load powered by the battery module 20 is a capacitive load.

[0135] In step S703 , the controller 213 sends a PWM signal with a set duty cycle to the power switch.

[0136] The controller 213 sends a PWM signal with a set duty cycle to the first switch Q1 of the power switch 211. When the battery module 20 is short-circuited, the output voltage of the output port 23 is very small or 0. When the battery module 20 supplies power to a capacitive load, the output voltage of the output port 23 gradually increases.

[0137] When the duty cycle is set to a fixed value, during the process of the controller 213 sending a PWM signal to the first switch Q1 of the power switch 211, in the first switching cycle, after the controller 213 controls the power switch 211 to be in the on state, the output voltage of the output port 23 will increase by ΔV. In the second switching cycle, after the controller 213 controls the power switch 211 to be in the on state, the output voltage of the output port 23 will increase by ΔV again based on the first switching cycle, that is, by 2ΔV. Similarly, in the Nth switching cycle, after the controller 213 controls the power switch 211 to be in the on state, the output voltage of the output port 23 will be NΔV.

[0138] When the duty cycle is set to a stepped duty cycle, during the process of controller 213 sending a PWM signal to first switch Q1 of power switch 211, the duty cycle of the PWM signal is D1 during the first switching cycle. During the second switching cycle, the duty cycle of the PWM signal is increased by a set duty cycle based on the first switching cycle, and the duty cycle of the PWM signal is recorded as D1 + ΔD1. During the third switching cycle, the duty cycle of the PWM signal is increased by a set duty cycle based on the second switching cycle, and the duty cycle of the PWM signal is recorded as D1 + 2ΔD1. Similarly, during the Mth switching cycle, the duty cycle of the PWM signal is D1 + (M-1)ΔD1.

[0139] Each time the PWM signal's duty cycle increases by the set duty cycle, the output voltage of output port 23 increases by a larger delta V. When the battery module 20 is powering a capacitive load, the time it takes for the output voltage Vbus of output port 23 to reach the set voltage is shortened. This reduces the time it takes for the controller 213 to send the PWM signal, lowering the risk of damage to other components in the battery module 20 and lowering electrical and thermal performance requirements.

[0140] In step S704, the controller 213 detects whether the output voltage of the output port 23 is less than the set voltage. If the output voltage of the output port 23 is less than the set voltage, step S705 is executed. If the output voltage of the output port 23 is not less than the set voltage, step S708 is executed.

[0141] In one embodiment, when the controller 213 detects that the output voltage Vbus of the output port 23 is not less than a set voltage, the controller 213 may determine that the load powered by the battery module 20 is a capacitive load. In other embodiments, when the controller 213 determines that the load powered by the battery module 20 is a capacitive load, the controller 213 may stop sending a PWM signal with a set duty cycle to the first switch Q1 of the power switch 211, thereby reducing the conduction time of the battery module 20 and reducing the risk of burning out the battery module 20.

[0142] In one embodiment, when the controller 213 detects that the output voltage Vbus of the output port 23 is less than a set voltage, the controller 213 may determine that the battery module 20 is short-circuited or the capacitance of the capacitive load is relatively large.

[0143] In the present application, when the duty cycle is set to a fixed value, the controller 213 again sends a PWM signal with a step duty cycle to the first switch Q1 of the power switch 211. The step duty cycle can be continuously increased from the set duty cycle to the full duty cycle. In one embodiment, in the first switching cycle after the third set time, the duty cycle of the PWM signal is D2. In the second switching cycle after the third set time, the duty cycle of the PWM signal is increased by a set duty cycle on the basis of the first switching cycle, and the duty cycle of the PWM signal is D2+△D2. In the third switching cycle after the third set time, the duty cycle of the PWM signal is increased by a set duty cycle on the basis of the second switching cycle, and the duty cycle of the PWM signal is D2+2△D2. And so on, until the duty cycle of the PWM signal sent by the controller 213 is the full duty cycle.

[0144] When the battery module 20 is powering a relatively large capacitive load, the controller 213 increases the duty cycle of the PWM signal from a set duty cycle to the full duty cycle. If the output voltage of the output port 23 reaches the set voltage during the increase in the PWM signal's duty cycle, the controller 213 can distinguish between a short circuit in the battery module 20 and a relatively large capacitive load. This reduces the risk of damage to other components in the battery module 20 and lowers electrical and thermal performance requirements.

[0145] In step S705 , the controller 213 sends a full-duty-cycle PWM signal to the power switch.

[0146] In step S706, the controller 213 detects whether the output voltage of the output port 23 is less than the set voltage. If the output voltage of the output port 23 is less than the set voltage, step S707 is executed. If the output voltage of the output port 23 is not less than the set voltage, step S708 is executed.

[0147] The controller 213 sends a full-duty PWM signal to the first switch Q1 of the power switch 211. While sending the PWM signal to the first switch Q1 of the power switch 211, the controller 213 collects the output voltage of the output port 23 in real time through the sampling circuit 212. The controller 213 can determine whether the load powered by the battery module 20 is a capacitive load with a relatively large capacitance based on whether the output voltage Vbus of the output port 23 is less than a set voltage.

[0148] In one embodiment, when the controller 213 detects that the output voltage Vbus of the output port 23 is not less than a set voltage, the controller 213 may determine that the capacitance of the capacitive load is relatively large. In one embodiment, when the controller 213 detects that the output voltage Vbus of the output port 23 is less than a set voltage, the controller 213 may determine that the battery module 20 is short-circuited.

[0149] In step S707 , the controller 213 determines that the battery module 20 is short-circuited.

[0150] In step S708 , the controller 213 determines that the load powered by the battery module 20 is a capacitive load.

[0151] When the controller 213 determines that the battery module 20 is supplying power to a capacitive load, it can stop pulsating and end the slow start, thereby shortening the detection time. When the controller 213 determines that the battery module 20 is short-circuited, it can stop pulsating and end the slow start.

[0152] In an embodiment of the present application, the controller 213 controls the duty cycle and time of sending a PWM signal to the first switch Q1 of the power switch 211, and can identify three situations in different time periods: the battery module 20 is supplying power to a capacitive load with a relatively small capacitance value, the battery module 20 is supplying power to a capacitive load with a large capacitance value, and the battery module 20 is short-circuited. For example, within the second set time, the controller 213 sends a full-duty cycle PWM signal to the first switch Q1 of the power switch 211 multiple times. When the controller 213 sends the PWM signal multiple times and triggers the overcurrent protection, the controller 213 can determine that the battery module 20 is short-circuited or that the load powered by the battery module 20 is a capacitive load.

[0153] Embodiments of the present application also provide a computer program product containing instructions. The computer program product may be software or a program product containing instructions that can be executed on a computing device or stored on any available medium. When the computer program product is executed on at least one computing device, the at least one computing device executes the battery module control method.

[0154] The present application also provides a computer-readable storage medium. The computer-readable storage medium can be any available medium that can be stored by a computing device or a data storage device such as a data center that contains one or more available media. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive). The computer-readable storage medium includes instructions that instruct the computing device to execute the control method of the battery module.

[0155] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the protection scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A battery module (20), characterized in that: include: a plurality of battery packs (22), an output port (23), electrically connected to a load, for allowing the battery module to provide electrical energy to the load; a power switch (211), coupled between the plurality of battery packs and the output port, for controlling the plurality of battery packs to transfer electrical energy to the output port; a sampling circuit (212), coupled to the output port, for collecting the output voltage of the output port; A controller (213) is configured to send a PWM signal with a set duty cycle to the power switch, wherein the PWM signal is configured to control the power switch to be in an on state; The controller is further configured to receive the output voltage collected by the sampling circuit, and in response to the output voltage being not less than a set voltage, determine that the load powered by the battery module is a capacitive load.

2. The battery module according to claim 1, wherein: The controller is further configured to send a full duty cycle PWM signal to the power switch; and An output voltage collected by the sampling circuit is received, and in response to the output voltage being less than the total voltage of the plurality of battery packs, it is determined that the load powered by the battery module is a capacitive load or the battery module is short-circuited.

3. The battery module according to claim 2, characterized in that: The controller is further configured to delay sending a full-duty cycle PWM signal to the power switch for a set time, wherein the set time is the time for the controller to start the multiple battery packs to discharge.

4. The battery module according to any one of claims 1 to 3, characterized in that: The controller is further configured to send a PWM signal with a stepped duty cycle to the power switch in response to the output voltage being not less than a set voltage; the stepped duty cycle being a variable duty cycle from the set duty cycle to the full duty cycle; The output voltage collected by the sampling circuit is received, and in response to the output voltage being equal to the total voltage of the plurality of battery packs, a full-duty cycle PWM signal is sent to the power switch.

5. The battery module according to any one of claims 1 to 4, characterized in that: The set duty cycle is a step duty cycle.

6. The battery module according to claim 4 or 5, characterized in that: The step duty cycle is a variable duty cycle that increases the set duty cycle at every interval of at least one switching cycle; wherein the value of the set duty cycle increases continuously each time.

7. The battery module according to any one of claims 1 to 6, characterized in that: The controller is further configured to send a full-duty cycle PWM signal to the power switch and receive the output voltage collected by the sampling circuit; In response to the output voltage being not less than a set voltage, determining that the load powered by the battery module is a capacitive load; In response to the output voltage being less than a set voltage, it is determined that the battery module is short-circuited.

8. A method for controlling a battery module, characterized in that: Application and battery module, the battery module includes multiple battery packs, an output port, a power switch, a sampling circuit and a controller; the power switch is coupled between the multiple battery packs and the output port; The sampling circuit is coupled to the output port; The controller is coupled to the power switch and the sampling circuit respectively; The method is executed by the controller and includes: controlling the plurality of battery packs to discharge; Sending a PWM signal with a set duty cycle to the power switch; the PWM signal is used to control the power switch to be in an on state; An output voltage collected by the sampling circuit is received, and in response to the output voltage being not less than a set voltage, a load powered by the battery module is determined to be a capacitive load.

9. The method according to claim 8, characterized in that Before sending the PWM signal for setting the duty cycle to the power switch, the method further includes: Sending a full duty cycle PWM signal to the power switch; An output voltage collected by the sampling circuit is received, and in response to the output voltage being less than the total voltage of the plurality of battery packs, it is determined that the load powered by the battery module is a capacitive load or the battery module is short-circuited.

10. The method according to claim 8 or 9, characterized in that The setting duty cycle is a fixed value, and the method further includes: In response to the output voltage being not less than a set voltage, sending a PWM signal with a stepped duty cycle to the power switch; the stepped duty cycle being a variable duty cycle from the set duty cycle to the full duty cycle; The output voltage collected by the sampling circuit is received, and in response to the output voltage being equal to the total voltage of the plurality of battery packs, a full-duty cycle PWM signal is sent to the power switch.

11. The method according to any one of claims 8 to 10, characterized in that: The set duty cycle is a step duty cycle.

12. The method according to any one of claims 8 to 11, characterized in that: The method further comprises: Sending a full-duty cycle PWM signal to the power switch and receiving the output voltage collected by the sampling circuit; In response to the output voltage being not less than a set voltage, determining that the load powered by the battery module is a capacitive load; In response to the output voltage being less than a set voltage, it is determined that the battery module is short-circuited.

13. An electric vehicle, characterized in that: include: At least one electrical device, A backup power device electrically connected to the at least one power-consuming device; the backup power device includes a power switch for controlling the backup power device to provide power to the at least one power-consuming device; The backup power device is configured to send a PWM signal with a set duty cycle to the power switch, wherein the PWM signal is configured to control the power switch to be in an on state; The backup power device is further configured to detect an output voltage, and in response to the output voltage being not less than a set voltage, determine that the power-consuming device powered by the backup power device is a capacitive load.

14. The electric vehicle according to claim 13, characterized in that: The backup power device is further configured to send a PWM signal with a stepped duty cycle to the power switch in response to the output voltage being not less than a set voltage; the stepped duty cycle being a variable duty cycle from the set duty cycle to the full duty cycle; The output voltage is detected, and in response to the output voltage being equal to the total voltage of the backup power device, a full duty cycle PWM signal is sent to the power switch.

15. The electric vehicle according to claim 13 or 14, characterized in that: The set duty cycle is a step duty cycle.

16. The electric vehicle according to any one of claims 13-14, characterized in that: The backup power device is further configured to send a full-duty cycle PWM signal to the power switch and detect the output voltage; In response to the output voltage being not less than a set voltage, determining that the power-consuming device powered by the backup power device is a capacitive load; In response to the output voltage being less than a set voltage, it is determined that the backup power device is short-circuited.

17. An electric power device, characterized in that: include: at least one electronic component, at least one battery module, electrically connected to the at least one electronic component; The battery module includes a power switch for controlling the battery module to provide power to the at least one electronic component; The battery module is configured to send a PWM signal with a set duty cycle to the power switch, wherein the PWM signal is configured to control the power switch to be in an on state; The battery module is further configured to detect an output voltage, and in response to the output voltage being not less than a set voltage, determine that the electronic component powered by the battery module is a capacitive load.

18. The electric power equipment according to claim 17, characterized in that The battery module is further configured to send a PWM signal with a stepped duty cycle to the power switch in response to the output voltage being not less than a set voltage; the stepped duty cycle being a variable duty cycle from the set duty cycle to the full duty cycle; The output voltage is detected, and in response to the output voltage being equal to the total voltage of the battery module, a full duty cycle PWM signal is sent to the power switch.

19. The electric power equipment according to claim 17 or 18, characterized in that: The set duty cycle is a step duty cycle.

20. The electric power equipment according to any one of claims 17 to 19, characterized in that: The battery module is further configured to send a full-duty cycle PWM signal to the power switch and detect the output voltage; In response to the output voltage being not less than a set voltage, determining that the electronic component powered by the battery module is a capacitive load; In response to the output voltage being less than a set voltage, it is determined that the battery module is short-circuited.

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