Hot plug protection slow start circuit and battery management system

Abstract

According to the hot plug protection slow start circuit and the battery management system provided by the invention, when hot plug is performed on the hot plug protection slow start circuit, namely within the set time of initial power-on of the hot plug protection slow start circuit by the battery pack, the control part of the buffer protection circuit controls the buffer part; therefore, the buffer part limits the current of the access where the buffer part is located, thereby effectively preventing the impact current from damaging the hot-plug protection slow-start circuit, improving the reliability of the hot-plug protection slow-start circuit, and prolonging the service life of the hot-plug protection slow-start circuit.

Description

[0001] This application claims the priority of the Chinese patent application filed with the China Patent Office on November 9, 2023, with application number 202311503125.1 and invention name “A hot-swap protection slow-start circuit and battery management system”, the entire contents of which are incorporated by reference in this application. Technical Field

[0002] The present invention relates to the technical field of battery management, and more specifically to a hot-swap protection slow-start circuit and a battery management system. Background Art

[0003] With the widespread application of new energy sources, the capacity, safety, health status and endurance of batteries are becoming increasingly the focus of attention. The battery management system is a system that monitors and controls the battery, and feeds back the collected battery information to the user in real time. At the same time, it adjusts the parameters according to the collected information to give full play to the performance of the battery. In the BMS (Battery Management System), the battery sampling chip is generally directly connected to the system, and it is assembled by hot plugging. When hot plugging the battery sampling chip, there are problems such as the first / last contact of the pins in the plug-in, the plug-in voltage shock, etc., which will generate a large current shock, resulting in damage or even damage to the devices in the battery sampling chip of the BMS, causing the chip to fail to work properly. Summary of the invention

[0004] In view of this, the present invention provides a hot-swap protection slow-start circuit and a battery management system, which effectively solve the technical problems existing in the prior art. When the hot-swap protection slow-start circuit is hot-plugged, it can effectively prevent the impact current from causing damage to the hot-swap protection slow-start circuit, thereby improving the reliability and service life of the hot-swap protection slow-start circuit.

[0005] To achieve the above purpose, the technical solution provided by the present invention is as follows:

[0006] A hot-swap protection slow-start circuit, a hot-swap protection slow-start circuit, the hot-swap protection slow-start circuit is electrically connected to a battery pack and a sampling chip, the battery pack includes a first battery to an N-th battery, and the first battery to the N-th battery are sequentially connected in series, N is an integer not less than 2, and the sampling chip includes a chip power supply terminal, a chip ground terminal and a first sampling terminal to an N-th sampling terminal;

[0007] The hot-swap protection slow-start circuit comprises:

[0008] A power supply terminal and a power supply ground terminal, the power supply terminal is electrically connected to the positive electrode of the first battery, and the power supply ground terminal is electrically connected to the negative electrode of the Nth battery; the chip power supply terminal is electrically connected to the power supply terminal, the chip ground terminal is electrically connected to the power supply ground terminal, and the i-th sampling terminal is electrically connected to the positive electrode of the i-th battery, where i is an integer not less than 1 and not greater than N;

[0009] and a main buffer protection circuit electrically connected to the power ground terminal, and / or an i-th branch buffer protection circuit electrically connected to the i-th sampling terminal, wherein both the main buffer protection circuit and the i-th branch buffer protection circuit include a control part and a buffer part, the control part is used to control the buffer part to limit the current of the path in which it is located within a set time when the battery pack is initially powered on, and control the buffer part to be short-circuited after the set time;

[0010] The buffer part of the main buffer protection circuit is electrically connected between the power ground terminal and the chip ground terminal, and the buffer part of the i-th branch buffer protection circuit is electrically connected between the i-th sampling terminal and the positive electrode of the i-th battery.

[0011] Optionally, when the hot-swap protection slow-start circuit only includes the main buffer protection circuit, the hot-swap protection slow-start circuit further includes:

[0012] an auxiliary buffer protection circuit electrically connected to at least one of the first sampling terminal to the Nth sampling terminal, wherein the auxiliary buffer protection circuit has the same structure as the main buffer protection circuit, and a buffer portion of the auxiliary buffer protection circuit is electrically connected between the sampling terminal and the positive electrode of the corresponding battery.

[0013] Optionally, the buffer part includes a current limiting resistor and a controllable switch;

[0014] The current limiting resistor and the controllable switch are connected in parallel, and the control end of the controllable switch is electrically connected to the control part;

[0015] The control part is used to control the controllable switch to be disconnected within a set time when the battery pack is initially powered on, so that the current limiting resistor limits the current in its path; and to control the controllable switch to be closed after the set time, so that the buffer part is short-circuited.

[0016] Optionally, the control part includes a voltage divider subcircuit and a charging capacitor;

[0017] The power supply end of the voltage divider subcircuit and the power supply end are powered on simultaneously, and the output end of the voltage divider subcircuit is electrically connected to the first plate of the charging capacitor and the control end of the buffer part, wherein the second plate of the charging capacitor of the main buffer protection circuit is electrically connected to the power ground end, and the second plate of the charging capacitor of the i-th branch buffer protection circuit is electrically connected to the positive electrode of the i-th battery.

[0018] Optionally, the power supply end of the voltage divider subcircuit is electrically connected to the power supply end; or,

[0019] The power supply end of the voltage divider subcircuit is electrically connected to the positive electrode of any battery; or,

[0020] The power supply end of the voltage divider subcircuit is electrically connected to an external power supply, and the power-on time of the external power supply is the same as that of the power supply end.

[0021] Optionally, the voltage-dividing subcircuit includes: a first voltage-dividing resistor and a second voltage-dividing resistor, wherein the first end of the first voltage-dividing resistor is a power supply end, the second end of the first voltage-dividing resistor and the first end of the second voltage-dividing resistor are electrically connected to form an output end, and the second end of the second voltage-dividing resistor is electrically connected to the second plate of the charging capacitor;

[0022] Alternatively, a voltage-dividing resistor and a voltage-stabilizing diode, wherein the first end of the voltage-dividing resistor is a power supply end, the second end of the voltage-dividing resistor and the cathode of the voltage-stabilizing diode are electrically connected as an output end, and the anode of the voltage-stabilizing diode is electrically connected to the second plate of the charging capacitor;

[0023] Alternatively, a voltage-dividing resistor and a voltage-dividing capacitor, the voltage-dividing capacitor of the voltage-dividing sub-circuit reuses the charging capacitor, the first end of the voltage-dividing resistor is the power supply end, and the second end of the voltage-dividing resistor is electrically connected to the first electrode plate of the voltage-dividing capacitor as the output end.

[0024] Optionally, the controllable switch is a MOS (Metal-Oxide-Semiconductor) transistor, a triode, a thyristor, or a relay.

[0025] Optionally, a fuse is connected in series between at least one of the power supply terminal and the chip power supply terminal, the power ground terminal and the chip ground terminal, and the positive electrode of the i-th battery and the i-th sampling terminal.

[0026] Optionally, a balancing subcircuit and a filtering subcircuit are electrically connected between the positive electrode of the i-th battery and the i-th sampling terminal;

[0027] The balancing subcircuit is used to balance the voltage difference between the i-th battery and other batteries, and the filtering subcircuit is used to filter the output voltage of the i-th battery.

[0028] Correspondingly, the present invention also provides a battery management system, which includes the above-mentioned hot-swap protection slow-start circuit.

[0029] Compared with the prior art, the technical solution provided by the present invention has at least the following advantages:

[0030] The present invention provides a hot-swap protection slow-start circuit and a battery management system. When the hot-swap protection slow-start circuit is hot-swapped, that is, within the set time when the hot-swap protection slow-start circuit is initially powered on by a battery pack, the control part of the buffer protection circuit controls the buffer part, so that the buffer part limits the current in its path, thereby effectively preventing the impact current from damaging the hot-swap protection slow-start circuit, thereby improving the reliability and service life of the hot-swap protection slow-start circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0032] Figure 1 A schematic diagram of the structure of a hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of the structure of another hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0034] Figure 3 A structural schematic diagram of another hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of the structure of another hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of the structure of another hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0037] Figure 6 A schematic diagram of the structure of another hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0038] Figure 7 A structural schematic diagram of another hot-swap protection slow-start circuit provided by an embodiment of the present invention;

[0039] Figure 8 A schematic diagram of the structure of a voltage divider subcircuit provided by an embodiment of the present invention;

[0040] Fig. 9 A schematic diagram of the structure of another voltage divider subcircuit provided by an embodiment of the present invention;

[0041] Fig.10 A schematic diagram of the structure of yet another voltage divider sub-circuit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] As described in the background technology, with the widespread application of new energy sources, the capacity, safety, health status and endurance of batteries have become increasingly the focus of attention. The battery management system is a system that monitors and controls the battery, and feeds back the collected battery information to the user in real time. At the same time, it adjusts the parameters according to the collected information to give full play to the performance of the battery. In the BMS (Battery Management System), the battery sampling chip is generally directly connected to the system, and it is assembled by hot plugging. When the battery sampling chip is hot-plugged, there are problems such as the first / last contact of the pins in the plug-in, the plug-in voltage shock, etc., which will generate a large current shock, resulting in damage or even damage to the components in the battery sampling chip of the BMS, causing the chip to fail to work properly.

[0044] Based on this, an embodiment of the present invention provides a hot-swap protection slow-start circuit and a battery management system, which effectively solves the technical problems existing in the prior art. When the hot-swap protection slow-start circuit is hot-plugged, it can effectively prevent the impact current from causing damage to the hot-swap protection slow-start circuit, thereby improving the reliability and service life of the hot-swap protection slow-start circuit.

[0045] To achieve the above purpose, the technical solution provided by the embodiment of the present invention is as follows, specifically combined with Figures 1 to 10 The technical solution provided by the embodiment of the present invention is described in more detail.

[0046] Combination Figures 1 to 3 As shown, Figure 1 A schematic diagram of a hot-swap protection slow-start circuit provided by an embodiment of the present invention is provided. Figure 2 A schematic diagram of the structure of another hot-swap protection slow-start circuit provided by an embodiment of the present invention, Figure 3A structural schematic diagram of another hot-swap protection slow-start circuit provided by an embodiment of the present invention. The hot-swap protection slow-start circuit provided by an embodiment of the present invention is electrically connected to a battery pack and a sampling chip, the battery pack includes a first battery 101 to an Nth battery 10n, and the first battery 101 to the Nth battery 10n are sequentially connected in series (i.e., the negative electrode of the first battery is electrically connected to the positive electrode of the second battery, and so on, until the negative electrode of the N-1th battery is electrically connected to the positive electrode of the Nth battery), N is an integer not less than 2, and the sampling chip 200 includes a chip power supply terminal 210, a chip ground terminal 220, and a first sampling terminal 201 to an Nth sampling terminal 20n. The sampling chip 200 can be an AFE (Analog Front End) chip circuit, and the sampling chip 200 described below is described by taking the AFE chip circuit as an example.

[0047] The hot-swap protection slow-start circuit includes: a power supply terminal V+ and a power ground terminal V-, the power supply terminal V+ is electrically connected to the positive electrode of the first battery 101, and the power ground terminal V- is electrically connected to the negative electrode of the Nth battery 10n. The chip power supply terminal 210 is electrically connected to the power supply terminal V+, the chip ground terminal 220 is electrically connected to the power ground terminal V-, and the i-th sampling terminal 20i is electrically connected to the positive electrode of the i-th battery 10i, i is an integer not less than 1 and not greater than N, that is, i ranges from 1 to N.

[0048] like Figure 1 As shown, the hot-swap protection slow-start circuit also includes a main buffer protection circuit 300 electrically connected to the power ground terminal V-. Figure 2 As shown, the hot-swap protection slow-start circuit also includes an i-th branch buffer protection circuit 30i electrically connected to the i-th sampling terminal 20i; or as Figure 3 As shown, the hot-swap protection slow-start circuit also includes a main buffer protection circuit 300 electrically connected to the power ground terminal V-, and an i-th branch buffer protection circuit 30i electrically connected to the i-th sampling terminal 20i.

[0049] The main buffer protection circuit 300 and the i-th branch buffer protection circuit 30i both include a control part 310 and a buffer part 320. The control part 310 is used to control the buffer part 320 to limit the current in its path within a set time when the battery pack is initially powered on, and to control the buffer part 320 to be short-circuited after the set time. The buffer part 320 of the main buffer protection circuit 300 is electrically connected in series between the power ground terminal V- and the chip ground terminal 220, and the buffer part 320 of the i-th branch buffer protection circuit 30i is electrically connected in series between the i-th sampling terminal 20i and the positive electrode of the i-th battery 10i.

[0050] In one embodiment of the present invention, when the hot-swap protection slow-start circuit provided by the embodiment of the present invention only includes a main buffer protection circuit but does not include an i-th branch buffer protection circuit, at least one sampling terminal is also electrically connected to an auxiliary buffer protection circuit. Figure 4 FIG. 1 is a schematic diagram of a structure of another hot-swap protection slow-start circuit provided by an embodiment of the present invention, wherein the hot-swap protection slow-start circuit only includes the main buffer protection circuit 300, that is, when Figure 1 On the basis of the hot-swap protection slow-start circuit shown, the hot-swap protection slow-start circuit also includes: an auxiliary buffer protection circuit 400 electrically connected to at least one sampling terminal 10n among the first sampling terminal 101 to the Nth sampling terminal, the auxiliary buffer protection circuit 400 has the same structure as the main buffer protection circuit 300, that is, the auxiliary buffer protection circuit 400 includes a control part 310 and a buffer part 320, and the buffer part 320 of the auxiliary buffer protection circuit 400 is electrically connected between the sampling terminal and the positive electrode of the corresponding battery; wherein the control part 310 is used to control the buffer part 320 to limit the current of the path in which it is located within a set time when the battery pack is initially powered on, and control the buffer part 320 to be short-circuited after the set time.

[0051] It can be understood that the technical solution provided by the embodiment of the present invention is that when the hot-swap protection slow-start circuit is hot-plugged, that is, within the set time when the battery pack initially powers on the hot-swap protection slow-start circuit, the control part of the buffer protection circuit controls the buffer part, so that the buffer part limits the current in its path, thereby effectively preventing the impact current from damaging the hot-swap protection slow-start circuit, thereby improving the reliability and service life of the hot-swap protection slow-start circuit.

[0052] The technical solution provided by the embodiment of the present invention is only a hardware improvement of the hot-swap protection slow-start circuit. Only ordinary electronic devices are needed to stably realize the protection function, so that the improvement requirements of the hot-swap protection slow-start circuit are relatively low, and the improvement cost of the hot-swap protection slow-start circuit is ensured to be low. In addition, the technical solution provided by the embodiment of the present invention is a pure hardware circuit improvement, which does not need to be controlled by software, so the circuit operation is highly stable, and there is no danger of circuit failure caused by software misoperation or downtime. In addition, no matter whether the voltage in the circuit is high or low, and the current is large or small, the relevant components in the buffer protection circuit are replaced according to the application scenario, such as replacing the controllable switch in the buffer protection circuit (the main buffer protection circuit, the auxiliary buffer protection circuit and the i-th buffer protection circuit are collectively referred to as the buffer protection circuit), so that the overcurrent capacity of the corresponding path from the power supply end to the power supply ground end and the path from the sampling end to the positive electrode of the battery depends entirely on the overcurrent capacity of the controllable switch, so that the buffer protection circuit can be applied to any scenario, which improves practicality. The buffer protection circuit provided by the embodiment of the present invention has a simple circuit and can be applied to various positions of the hot-swap protection slow-start circuit, playing a buffering role and improving flexibility. In addition, after the bus power supply end and the bus ground end are powered on and stabilized, the buffer protection circuit can control the buffer part to achieve short circuit, so that the corresponding path from the power supply end to the power ground end, and the path from the sampling end to the positive electrode of the battery are normally connected, avoiding interference with the normal operation of the hot plug protection slow start circuit.

[0053] Furthermore, the embodiment of the present invention can also optimize the hot-swap protection slow-start circuit to further improve the reliability of the hot-swap protection slow-start circuit. Figures 1 to 4 As shown, a fuse 230 is also connected in series between at least one of the power supply terminal V+ to the chip power supply terminal 210, the power ground terminal V- to the chip ground terminal 220, and the positive electrode of the i-th battery 10i to the i-th sampling terminal 20i provided in the embodiment of the present invention. The fuse 230 is used to further protect the devices in the AFE chip circuit 200 from being damaged.

[0054] In addition, a balancing subcircuit 241 and a filtering subcircuit 242 are electrically connected between the positive electrode of the i-th battery 10i and the i-th sampling terminal 20i provided in the embodiment of the present invention; the balancing subcircuit 241 is used to balance the voltage difference between the i-th battery 10i and other batteries, and the filtering subcircuit 242 is used to filter the output voltage of the i-th battery 10i.

[0055] Optionally, the balancing subcircuit 241 and the filtering subcircuit 242 electrically connected to the i-th sampling terminal 20i provided in the embodiment of the present invention can be electrically connected between the fuse 230 and the i-th sampling terminal 20i, and the balancing subcircuit 241 and the filtering subcircuit 242 each include a resistor and a capacitor connected in parallel, the first end of the resistor is electrically connected to the fuse 230, the second end of the resistor is electrically connected to the first plate of the capacitor and the i-th sampling terminal 20i, respectively, and the second plate of the capacitor is electrically connected to the ground terminal.

[0056] Furthermore, a resistor and a bus-controllable switch are connected in series between the power supply terminal V+ and the chip power supply terminal 210 provided in the embodiment of the present invention, the control end of the bus-controllable switch can be electrically connected to the AFE chip circuit 200, and the chip power supply terminal 210 is also connected to the first plate of a capacitor, and the second plate of the capacitor is connected to the ground terminal.

[0057] It should be noted that the i-th sampling terminal of the AFE chip circuit provided in the embodiment of the present invention can be a single pin port, or a combination of multiple pin ports, which needs to be specifically analyzed according to the specific structure of the AFE chip circuit, and the present invention does not make specific restrictions. In addition, the specific device composition and connection of the equalization subcircuit and the filtering subcircuit in the embodiment of the present invention are not limited to the device composition and connection mode provided in the above embodiment, and the present invention does not make specific restrictions on this.

[0058] The buffer protection circuit provided by the embodiment of the present invention is described in more detail below with reference to the accompanying drawings. Figure 5 As shown, it is a structural schematic diagram of another hot-swap protection slow-start circuit provided in an embodiment of the present invention, wherein the buffer part 320 provided in the embodiment of the present invention includes a current limiting resistor R and a controllable switch Mk; the current limiting resistor R and the controllable switch Mk are connected in parallel, and the control end of the controllable switch Mk is electrically connected to the control part 310; the control part 310 is used to control the controllable switch Mk to be disconnected within a set time when the battery pack is initially powered on, so that the current limiting resistor R limits the current in the path where it is located; and after the set time, the controllable switch Mk is controlled to be closed, so that the buffer part 320 is short-circuited.

[0059] The controllable switch of the main buffer protection circuit provided in the embodiment of the present invention is connected in series between the power ground terminal and the chip ground terminal; the controllable switch of the i-th branch buffer protection circuit is connected in series between the positive electrode of the i-th battery and the i-th sampling terminal; and the controllable switch of the auxiliary buffer protection circuit is connected in series between the sampling terminal where it is located and the positive electrode of the corresponding battery. Optionally, the controllable switch provided in the embodiment of the present invention can be a MOS transistor, or a triode, or a thyristor, or a relay, which is not specifically limited in the embodiment of the present invention.

[0060] It can be understood that the control part provided in the embodiment of the present invention controls the controllable switch to be disconnected within the set time when the battery pack is initially powered on, so the current can only be transmitted through the path where the current limiting resistor is located, and the current limiting resistor can limit the current flowing through to protect the AFE chip circuit. In addition, after the set time, the control part will control the controllable switch to be closed, and the closing of the control switch is equivalent to bypassing the current limiting resistor, short-circuiting the current path through the control switch, and the current is transmitted through the control switch to ensure the normal operation of the hot plug protection slow start circuit.

[0061] Continue as Figure 5 As shown, the control part 310 provided by the embodiment of the present invention includes a voltage divider circuit 311 and a charging capacitor C; the power supply end of the voltage divider circuit 311 and the power supply end V+ are powered on at the same time, and the output end of the voltage divider circuit 311 is electrically connected to the first plate of the charging capacitor C and the control end of the buffer part 320 (that is, electrically connected to the control end of the controllable switch Mk), wherein the second plate of the charging capacitor C of the main buffer protection circuit is electrically connected to the power ground end V-, and the second plate of the charging capacitor C of the i-th branch buffer protection circuit 30i is electrically connected to the positive electrode of the i-th battery 10i. And the second plate of the charging capacitor C of the auxiliary buffer protection circuit 400 is electrically connected to the positive electrode of the corresponding battery (such as Figure 6 The structural schematic diagram of the hot-swap protection slow-start circuit is shown in FIG.

[0062] In order to ensure that the power supply end and the power supply end of the voltage divider circuit are powered on at the same time, Figure 7 As shown, the power supply end of the voltage divider subcircuit 310 provided in the embodiment of the present invention is electrically connected to the power supply end V+. Alternatively, the power supply end of the voltage divider subcircuit is electrically connected to the positive electrode of any battery, wherein the power supply end of the voltage divider subcircuit is electrically connected to the positive electrode of the battery corresponding to the corresponding sampling end, as shown in FIG. Figure 5 The power supply end of the voltage divider subcircuit 310 of the i-th branch buffer protection circuit 30i shown can be electrically connected to the positive electrode of the battery corresponding to the corresponding i-th sampling terminal 20i; in addition, the power supply end of the voltage divider subcircuit can also be electrically connected to the positive electrode of the battery corresponding to other sampling terminals. Alternatively, the power supply end of the voltage divider subcircuit is electrically connected to an external power supply, and the power-on time of the external power supply is the same as that of the power supply end; it should be noted that the voltage condition when the external power supply is powered on is consistent with the voltage condition when the power supply end is powered on, ensuring that the controllable switch is controlled to be turned off within the set time, and the controllable switch is controlled to be turned on after the set time.

[0063] It should be noted that the power supply end of the voltage divider subcircuit provided in the embodiment of the present invention can be electrically connected to the side of the fuse away from the AFE chip circuit, and the current limiting resistor and the controllable switch are electrically connected between the fuse and the AFE chip circuit. The present invention does not make specific limitations on this.

[0064] It can be understood that in the buffer protection circuit provided by the embodiment of the present invention, at the initial stage of power-on at the power end, the controllable switch is in the off state, and the current limiting resistor at this time will play a current limiting role. Then, after the power-on at the power end ends and tends to be stable, the voltage across the current limiting resistor is stable, and the voltage of the charging capacitor reaches a certain threshold after a set time. At this time, the controllable switch is controlled to be turned on to bypass the current limiting resistor to ensure the normal operation of the hot plug protection slow start circuit.

[0065] In one embodiment of the present invention, the capacitance of the charging capacitor provided by the embodiment of the present invention can be calculated by referring to the time constant of the voltage divider resistor and capacitor in the voltage divider subcircuit, and the present invention does not make any specific restrictions on this. Also, the controllable switch is preferably a switch with a smaller internal resistance. If the current in the current loop is large, a power type switch is preferably selected, and this needs to be specifically selected according to the actual application.

[0066] refer to Figure 8 As shown, it is a structural schematic diagram of a voltage-dividing sub-circuit provided in an embodiment of the present invention, taking the main buffer protection circuit as an example, wherein the voltage-dividing sub-circuit provided in an embodiment of the present invention includes: a first voltage-dividing resistor R1 and a second voltage-dividing resistor R2, the first end of the first voltage-dividing resistor R1 is a power supply end, the second end of the first voltage-dividing resistor R1 and the first end of the second voltage-dividing resistor R2 are electrically connected as an output end, and the second end of the second voltage-dividing resistor R2 is electrically connected to the second plate of the charging capacitor C.

[0067] It should be noted that the first voltage-dividing resistor and the second voltage-dividing resistor provided in the embodiment of the present invention are preferably high-precision resistors, while the current-limiting resistor is not required; wherein, the resistance value of the current-limiting resistor needs to be specifically analyzed based on the actual application, and the present invention does not make any specific restrictions.

[0068] Or refer to Fig. 9 As shown, it is a structural schematic diagram of another voltage divider sub-circuit provided in an embodiment of the present invention, wherein the voltage divider sub-circuit includes: a voltage divider resistor R3 and a voltage zener diode D, the first end of the voltage divider resistor R3 is a power supply end, the second end of the voltage divider resistor R3 and the cathode of the voltage zener diode D are electrically connected as an output end, and the anode of the voltage zener diode D is electrically connected to the second plate of the charging capacitor C.

[0069] Or refer to Fig.10 As shown, it is a structural schematic diagram of another voltage-dividing sub-circuit provided in an embodiment of the present invention, wherein the voltage-dividing sub-circuit includes: a voltage-dividing resistor R4 and a voltage-dividing capacitor C1, the voltage-dividing capacitor C1 reuses the charging capacitor C, the first end of the voltage-dividing resistor R4 is the power supply end, and the second end of the voltage-dividing resistor R4 is electrically connected to the first plate of the voltage-dividing capacitor C1 as the output end.

[0070] It should be noted that the voltage divider circuit provided in the embodiment of the present invention is not limited to the above Figures 8 to 10The three methods shown can also be combined connection methods of other devices in other embodiments of the present invention, and the present invention does not make any specific limitation on this.

[0071] Correspondingly, an embodiment of the present invention further provides a battery management system, and the battery management system includes the hot-swap protection slow-start circuit provided by any one of the above embodiments.

[0072] The embodiment of the present invention provides a hot-swap protection slow-start circuit and a battery management system. When the hot-swap protection slow-start circuit is hot-swapped, that is, within the set time when the hot-swap protection slow-start circuit is initially powered on by the battery pack, the control part of the buffer protection circuit controls the buffer part, so that the buffer part limits the current in its path, thereby effectively preventing the impact current from damaging the hot-swap protection slow-start circuit, thereby improving the reliability and service life of the hot-swap protection slow-start circuit.

[0073] In the description of the present invention, it is necessary to understand that the orientation or position relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention 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, and therefore cannot be understood as limiting the present invention.

[0074] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0075] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0076] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0077] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc., mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0078] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A hot-swap protection slow-start circuit, the hot-swap protection slow-start circuit is electrically connected to a battery pack and a sampling chip, the battery pack includes a first battery to an Nth battery, and the first battery to the Nth battery are sequentially connected in series, N is an integer not less than 2, and the sampling chip includes a chip power terminal, a chip ground terminal, and a first sampling terminal to an Nth sampling terminal; It is characterized in that The hot-swap protection slow-start circuit comprises: A power supply terminal and a power supply ground terminal, the power supply terminal is electrically connected to the positive electrode of the first battery, and the power supply ground terminal is electrically connected to the negative electrode of the Nth battery; the chip power supply terminal is electrically connected to the power supply terminal, the chip ground terminal is electrically connected to the power supply ground terminal, and the i-th sampling terminal is electrically connected to the positive electrode of the i-th battery, where i is an integer not less than 1 and not greater than N; and a main buffer protection circuit electrically connected to the power ground terminal, and / or an i-th branch buffer protection circuit electrically connected to the i-th sampling terminal, wherein both the main buffer protection circuit and the i-th branch buffer protection circuit include a control part and a buffer part, the control part is used to control the buffer part to limit the current of the path in which it is located within a set time when the battery pack is initially powered on, and control the buffer part to be short-circuited after the set time; The buffer part of the main buffer protection circuit is electrically connected between the power ground terminal and the chip ground terminal, and the buffer part of the i-th branch buffer protection circuit is electrically connected between the i-th sampling terminal and the positive electrode of the i-th battery.

2. The hot-swap protection slow-start circuit according to claim 1, characterized in that: When the hot-swap protection slow-start circuit only includes the main buffer protection circuit, the hot-swap protection slow-start circuit further includes: an auxiliary buffer protection circuit electrically connected to at least one of the first sampling terminal to the Nth sampling terminal, wherein the auxiliary buffer protection circuit has the same structure as the main buffer protection circuit, and a buffer portion of the auxiliary buffer protection circuit is electrically connected between the sampling terminal and the positive electrode of the corresponding battery.

3. The hot-swap protection slow-start circuit according to claim 1 or 2, characterized in that: The buffer part includes a current limiting resistor and a controllable switch; The current limiting resistor and the controllable switch are connected in parallel, and the control end of the controllable switch is electrically connected to the control part; The control part is used to control the controllable switch to be disconnected within a set time when the battery pack is initially powered on, so that the current limiting resistor limits the current in its path; and to control the controllable switch to be closed after the set time, so that the buffer part is short-circuited.

4. The hot-swap protection slow-start circuit according to claim 1 or 2, characterized in that: The control part includes a voltage dividing subcircuit and a charging capacitor; The power supply end of the voltage divider subcircuit and the power supply end are powered on simultaneously, and the output end of the voltage divider subcircuit is electrically connected to the first plate of the charging capacitor and the control end of the buffer part, wherein the second plate of the charging capacitor of the main buffer protection circuit is electrically connected to the power ground end, and the second plate of the charging capacitor of the i-th branch buffer protection circuit is electrically connected to the positive electrode of the i-th battery.

5. The hot-swap protection slow-start circuit according to claim 4, characterized in that: The power supply end of the voltage divider subcircuit is electrically connected to the power supply end; or, The power supply end of the voltage divider subcircuit is electrically connected to the positive electrode of any battery; or, The power supply end of the voltage divider subcircuit is electrically connected to an external power supply, and the power-on time of the external power supply is the same as that of the power supply end.

6. The hot-swap protection slow-start circuit according to claim 4, characterized in that: The voltage-dividing subcircuit comprises: a first voltage-dividing resistor and a second voltage-dividing resistor, wherein the first end of the first voltage-dividing resistor is a power supply end, the second end of the first voltage-dividing resistor and the first end of the second voltage-dividing resistor are electrically connected to form an output end, and the second end of the second voltage-dividing resistor is electrically connected to the second electrode plate of the charging capacitor; Alternatively, a voltage-dividing resistor and a voltage-stabilizing diode, wherein the first end of the voltage-dividing resistor is a power supply end, the second end of the voltage-dividing resistor and the cathode of the voltage-stabilizing diode are electrically connected as an output end, and the anode of the voltage-stabilizing diode is electrically connected to the second plate of the charging capacitor; Alternatively, a voltage-dividing resistor and a voltage-dividing capacitor, the voltage-dividing capacitor of the voltage-dividing sub-circuit reuses the charging capacitor, the first end of the voltage-dividing resistor is the power supply end, and the second end of the voltage-dividing resistor is electrically connected to the first electrode plate of the voltage-dividing capacitor as the output end.

7. The hot-swap protection slow-start circuit according to claim 3, characterized in that: The controllable switch is a MOS transistor, a triode, a thyristor, or a relay.

8. The hot-swap protection slow-start circuit according to claim 1, characterized in that: A fuse is also connected in series between at least one of the power supply terminal and the chip power supply terminal, the power ground terminal and the chip ground terminal, and the positive electrode of the i-th battery and the i-th sampling terminal.

9. The hot-swap protection slow-start circuit according to claim 1, characterized in that: A balancing subcircuit and a filtering subcircuit are also electrically connected between the positive electrode of the i-th battery and the i-th sampling terminal; The balancing subcircuit is used to balance the voltage difference between the i-th battery and other batteries, and the filtering subcircuit is used to filter the output voltage of the i-th battery.

10. A battery management system, characterized in that: The battery management system includes the hot-swap protection slow-start circuit described in any one of claims 1-9.

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