A circuit for solving the problem that the temperature protection parameters in a pure hardware BMS are fixed and single

Abstract

The present invention discloses a circuit for solving the problem that the temperature protection parameters in a pure hardware BMS are fixed and single, which includes a battery module, an AFE chip U1, a power conversion module, a control module, a discharge high-temperature module, a first charging high-temperature module, a first charging low-temperature module, a second charging high-temperature module, a second charging low-temperature module, a discharge low-temperature module, a thermistor module, and a power supply VCC. The present invention solves the problem that there is no protection function for discharge low temperature in the pure hardware solution, and realizes the protection function for discharge low temperature by adding a thermistor RT2; the present invention solves the problem of fewer temperature detection ports in the pure hardware solution; the present invention enables the pure hardware BMS solution not to cause more complex logic problems due to changes during temperature detection and temperature protection.

Description

Technical Field

[0001] The present invention relates to a circuit for solving the problem of fixed and single temperature protection parameters in a pure hardware BMS. Background Art

[0002] In the battery pure hardware protection scheme, the scheme for temperature acquisition and temperature protection is as Figure 1 shown. There is an internal detection pin NTC. When the protection temperature value set by the protection IC is reached, corresponding protection actions are executed according to the internal protection logic. Taking the widely used pure hardware scheme in the market as an example, the temperature protection of the pure hardware scheme is as Figure 2 shown, and it has the following disadvantages: 1. The parameters are single. The protection values for charging low temperature, charging high temperature, and discharging high temperature are only several in the selection list, which is very single; 2. The parameters are fixed. Once the model of the protection IC is selected, the temperature protection value will be fixed; 3. The matching problem with the battery cell. The allowable charging and discharging temperatures of the commonly used battery cells in the market cannot be completely matched with the selected protection parameters, as Figure 3 shown; 4. Some pure hardware schemes do not have discharging low temperature protection. Using lithium batteries in a harsh low temperature environment will have a negative impact on the product experience and the battery cell life. Summary of the Invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a circuit for solving the problem of fixed and single temperature protection parameters in a pure hardware BMS.

[0004] To achieve the above purpose, the present invention is realized through the following technical solutions:

[0005] A circuit for solving the problem that the temperature protection parameters in a pure hardware BMS are fixed and single, including a battery module, an AFE chip U1, a power conversion module, a control module, a discharge high-temperature module, a first charge high-temperature module, a first charge low-temperature module, a second charge high-temperature module, a second charge low-temperature module, a discharge low-temperature module, a thermistor module, and a power supply VCC. The battery module is formed by connecting a plurality of battery cells BT in series. The control module and the battery module are both connected to the AFE chip U1. The battery module, the discharge high-temperature module, the first charge high-temperature module, the first charge low-temperature module, the second charge high-temperature module, the second charge low-temperature module, and the discharge low-temperature module are all connected to the power conversion module. The discharge high-temperature module, the first charge high-temperature module, the first charge low-temperature module, the second charge high-temperature module, the second charge low-temperature module, the discharge low-temperature module, and the thermistor module are all connected to the control module. The discharge high-temperature module, the first charge high-temperature module, the first charge low-temperature module, the second charge high-temperature module, the second charge low-temperature module, and the discharge low-temperature module are all connected to the thermistor module. The power conversion module, the discharge high-temperature module, the first charge high-temperature module, the first charge low-temperature module, the second charge high-temperature module, the second charge low-temperature module, the discharge low-temperature module, and the thermistor module are all connected to the power supply VCC.

[0006] Preferably, the power conversion module includes a resistor R2, a resistor R3, a resistor R4, a resistor R9, a three-terminal voltage regulator D1, a diode D6, a triode Q1, and a power supply VCC. One end of the resistor R2 is connected to the battery module, and the other end of the resistor R2 is connected to the collector of the triode Q1. The collector of the triode Q1 is connected to the base of the triode Q1 through the resistor R3. The base of the triode Q1 is connected to the ground signal through the diode D6. The emitter of the triode Q1 is connected to the K pole of the three-terminal voltage regulator D1. The A pole of the three-terminal voltage regulator D1 is connected to the ground signal GND. The R pole of the three-terminal voltage regulator D1 is connected to the ground signal GND through the resistor R9. The R pole of the three-terminal voltage regulator D1 is connected to the power supply VCC through the resistor R4. The R pole of the three-terminal voltage regulator D1 outputs Vref.

[0007] Preferably, the discharge high-temperature module includes a voltage comparator U1A, a diode D2, and a resistor R5. The negative pole of the diode D2 is connected to the control module, and the positive pole of the diode D2 is connected to the output terminal of the voltage comparator U1A. The positive pole of the diode D2 is connected to the power supply VCC through the resistor R5. The non-inverting input terminal of the voltage comparator U1A is connected to the thermistor module, and the inverting input terminal of the voltage comparator U1A is connected to the R pole of the three-terminal voltage regulator D1.

[0008] Preferably, the first charging high-temperature module includes a diode D7, a resistor R6, and a voltage comparator U1B. The negative electrode of the diode D7 is connected to the control module, the positive electrode of the diode D7 is connected to the output terminal of the voltage comparator U1B, the positive electrode of the diode D7 is connected to the power supply VCC through the resistor R6, the non-inverting input terminal of the voltage comparator U1B is connected to the thermistor module, and the inverting input terminal of the voltage comparator U1B is connected to the R pole of the three-terminal voltage regulator D1.

[0009] Preferably, the first charging low-temperature module includes a diode D4, a resistor R7, and a voltage comparator U1C. The positive electrode of the diode D4 is connected to the output terminal of the voltage comparator U1C, the positive electrode of the diode D4 is connected to the power supply VCC through the resistor R7, the non-inverting input terminal of the voltage comparator U1C is connected to the thermistor module, and the inverting input terminal of the voltage comparator U1C is connected to the R pole of the three-terminal voltage regulator D1.

[0010] Preferably, the second charging high-temperature module includes a diode D3, a resistor R8, and a voltage comparator U2A. The positive electrode of the diode D3 is connected to the output terminal of the voltage comparator U2A, the positive electrode of the diode D3 is connected to the power supply VCC through the resistor R8, the non-inverting input terminal of the voltage comparator U2A is connected to the thermistor module, and the inverting input terminal of the voltage comparator U2A is connected to the R pole of the three-terminal voltage regulator D1.

[0011] Preferably, the second charging low-temperature module includes a diode D8, a resistor R18, and a voltage comparator U2B. The positive electrode of the diode D8 is connected to the output terminal of the voltage comparator U2B, the positive electrode of the diode D8 is connected to the power supply VCC through the resistor R18, the non-inverting input terminal of the voltage comparator U2B is connected to the thermistor module, and the inverting input terminal of the voltage comparator U2B is connected to the R pole of the three-terminal voltage regulator D1.

[0012] Preferably, the discharging low-temperature module includes a diode D5, a resistor R19, and a voltage comparator U2C. The positive electrode of the diode D5 is connected to the output terminal of the voltage comparator U2C, the positive electrode of the diode D5 is connected to the power supply VCC through the resistor R19, the non-inverting input terminal of the voltage comparator U2C is connected to the thermistor module, and the inverting input terminal of the voltage comparator U2C is connected to the R pole of the three-terminal voltage regulator D1.

[0013] Preferably, the thermistor module includes a resistor R12, a resistor R13, a resistor R14, a resistor R15, a thermistor RT1, a resistor R20, a resistor R21, a resistor R22, a resistor R23, and a thermistor RT2. One end of the resistor R13 is connected to the ground signal GND. The other end of the resistor R13 is connected to the non-inverting input terminal of the voltage comparator U1A. The other end of the resistor R13 is connected to one end of the resistor R14. The other end of the resistor R14 is connected to the non-inverting input terminal of the voltage comparator U1B. The other end of the resistor R14 is connected to one end of the resistor R12. The other end of the resistor R12 is connected to the non-inverting input terminal of the voltage comparator U1C. The other end of the resistor R12 is connected to one end of the thermistor RT1 through the resistor R15. The other end of the thermistor RT1 is connected to the power supply VCC. One end of the resistor R21 is connected to the power supply VCC. The other end of the resistor R21 is connected to one end of the resistor R22. The other end of the resistor R22 is connected to the non-inverting input terminal of the voltage comparator U2A. The other end of the resistor R22 is connected to one end of the resistor R20. The other end of the resistor R20 is connected to the non-inverting input terminal of the voltage comparator U2B. The other end of the resistor R20 is connected to one end of the resistor R23. The other end of the resistor R23 is connected to the non-inverting input terminal of the voltage comparator U2C. The other end of the resistor R23 is connected to the ground signal GND through the thermistor RT2.

[0014] Preferably, the control module includes a capacitor C1, a resistor R1, a resistor R10, a resistor R11, a resistor R16, a resistor R17, a triode Q2, and a triode Q3. One end of the capacitor C1 is connected to the NTC terminal of the AFE chip U1. The other end of the capacitor C1 is connected to the ground signal GND. The resistor R1 is connected in parallel with the capacitor C1. One end of the resistor R10 is connected to the NTC terminal of the AFE chip U1. The other end of the resistor R10 is connected to the collector of the triode Q3. The emitter of the triode Q3 is connected to the ground signal GND. The base of the triode Q3 is connected to one end of the resistor R17. The other end of the resistor R17 is connected to the negative electrodes of the diodes D7, D4, D3, and D8. One end of the resistor R11 is connected to the NTC terminal of the AFE chip U1. The other end of the resistor R11 is connected to the collector of the triode Q2. The emitter of the triode Q2 is connected to the ground signal GND. The base of the triode Q2 is connected to one end of the resistor R16. The other end of the resistor R16 is connected to the negative electrodes of the diodes D2 and D5.

[0015] The beneficial effects of the present invention are as follows: The present invention solves the problem that the temperature protection parameters in the pure hardware solution are single and fixed. As long as the resistance values of the corresponding voltage-dividing resistors R13, resistor R14, resistor R12, resistor R15, resistor R21, resistor R22, and resistor R20 are calculated and replaced, the parameters of any protection temperature can be adjusted; the present invention solves the problem that there is no protection function for low-temperature discharge in the pure hardware solution, and realizes the protection function for low-temperature discharge by adding a thermistor RT2; the present invention can increase the multi-channel temperature detection, and more temperature thermistors can be extended and connected through the same solution, solving the problem of few temperature detection ports in the pure hardware solution; the present invention does not change the temperature protection control logic of the pure hardware, reasonably classifies the protection states of the pure hardware solution, and then controls it to be in the corresponding working state, so that the BMS solution of the pure hardware will not cause more complex logic problems due to changes during temperature detection and temperature protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the temperature acquisition and temperature protection solution in the background art;

[0017] Figure 2 is the temperature protection value of the pure hardware solution in the background art;

[0018] Figure 3 is the temperature value allowed for charge and discharge of the battery cells commonly used in the market;

[0019] Figure 4 is the circuit schematic diagram of the present invention;

[0020] Figure 5 is the temperature state classification diagram. DETAILED DESCRIPTION OF THE INVENTION

[0021] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings of the specification:

[0022] As Figure 4As shown in the figure, a circuit for solving the problem of fixed and single temperature protection parameters in a pure hardware BMS includes a battery module 1, an AFE chip U1, a power conversion module 2, a control module 3, a discharge high-temperature module 4, a first charge high-temperature module 5, a first charge low-temperature module 6, a second charge high-temperature module 7, a second charge low-temperature module 8, a discharge low-temperature module 9, a thermistor module 10, and a power supply VCC. The battery module 1 is formed by connecting a plurality of battery cells BT in series. The control module 3 and the battery module 1 are both connected to the AFE chip U1. The battery module 1, the discharge high-temperature module 4, the first charge high-temperature module 5, the first charge low-temperature module 6, the second charge high-temperature module 7, the second charge low-temperature module 8, and the discharge low-temperature module 9 are all connected to the power conversion module 2. The discharge high-temperature module 4, the first charge high-temperature module 5, the first charge low-temperature module 6, the second charge high-temperature module 7, the second charge low-temperature module 8, the discharge low-temperature module 9, and the thermistor module 10 are all connected to the control module 3. The discharge high-temperature module 4, the first charge high-temperature module 5, the first charge low-temperature module 6, the second charge high-temperature module 7, the second charge low-temperature module 8, and the discharge low-temperature module 9 are all connected to the thermistor module 10. The power conversion module 2, the discharge high-temperature module 4, the first charge high-temperature module 5, the first charge low-temperature module 6, the second charge high-temperature module 7, the second charge low-temperature module 8, the discharge low-temperature module 9, and the thermistor module 10 are all connected to the power supply VCC. The power supply VCC is 5V. The battery module 1 is formed by connecting a plurality of battery cells BT in series. Each battery cell BT is 4.2V when fully charged, and B+ provided by the battery module 1 is the sum of several 4.2V values.

[0023] As Figure 4 shown in the figure, the power conversion module 2 includes a resistor R2, a resistor R3, a resistor R4, a resistor R9, a three-terminal voltage regulator D1, a diode D6, a triode Q1, and a power supply VCC. One end of the resistor R2 is connected to the battery module 1, and the other end of the resistor R2 is connected to the collector of the triode Q1. The collector of the triode Q1 is connected to the base of the triode Q1 through the resistor R3. The base of the triode Q1 is connected to the ground signal through the diode D6. The emitter of the triode Q1 is connected to the K pole of the three-terminal voltage regulator D1. The A pole of the three-terminal voltage regulator D1 is connected to the ground signal GND. The R pole of the three-terminal voltage regulator D1 is connected to the ground signal GND through the resistor R9. The R pole of the three-terminal voltage regulator D1 is connected to the power supply VCC through the resistor R4. The R pole of the three-terminal voltage regulator D1 outputs Vref.

[0024] As Figure 4As shown, the high-temperature discharge module 4 includes a voltage comparator U1A, a diode D2, and a resistor R5. The negative electrode of the diode D2 is connected to the control module 3, the positive electrode of the diode D2 is connected to the output terminal of the voltage comparator U1A, the positive electrode of the diode D2 is connected to the power supply VCC through the resistor R5, the non-inverting input terminal of the voltage comparator U1A is connected to the thermistor module 10, and the inverting input terminal of the voltage comparator U1A is connected to the R pole of the three-terminal voltage regulator D1.

[0025] As Figure 4 shown, the first high-temperature charging module 5 includes a diode D7, a resistor R6, and a voltage comparator U1B. The negative electrode of the diode D7 is connected to the control module 3, the positive electrode of the diode D7 is connected to the output terminal of the voltage comparator U1B, the positive electrode of the diode D7 is connected to the power supply VCC through the resistor R6, the non-inverting input terminal of the voltage comparator U1B is connected to the thermistor module 10, and the inverting input terminal of the voltage comparator U1B is connected to the R pole of the three-terminal voltage regulator D1.

[0026] As Figure 4 shown, the first low-temperature charging module 6 includes a diode D4, a resistor R7, and a voltage comparator U1C. The positive electrode of the diode D4 is connected to the output terminal of the voltage comparator U1C, the positive electrode of the diode D4 is connected to the power supply VCC through the resistor R7, the non-inverting input terminal of the voltage comparator U1C is connected to the thermistor module 10, and the inverting input terminal of the voltage comparator U1C is connected to the R pole of the three-terminal voltage regulator D1.

[0027] As Figure 4 shown, the second high-temperature charging module 7 includes a diode D3, a resistor R8, and a voltage comparator U2A. The positive electrode of the diode D3 is connected to the output terminal of the voltage comparator U2A, the positive electrode of the diode D3 is connected to the power supply VCC through the resistor R8, the non-inverting input terminal of the voltage comparator U2A is connected to the thermistor module 10, and the inverting input terminal of the voltage comparator U2A is connected to the R pole of the three-terminal voltage regulator D1.

[0028] As Figure 4 shown, the second low-temperature charging module 8 includes a diode D8, a resistor R18, and a voltage comparator U2B. The positive electrode of the diode D8 is connected to the output terminal of the voltage comparator U2B, the positive electrode of the diode D8 is connected to the power supply VCC through the resistor R18, the non-inverting input terminal of the voltage comparator U2B is connected to the thermistor module 10, and the inverting input terminal of the voltage comparator U2B is connected to the R pole of the three-terminal voltage regulator D1.

[0029] As Figure 4As shown in the figure, the discharge low-temperature module 9 includes a diode D5, a resistor R19, and a voltage comparator U2C. The positive electrode of the diode D5 is connected to the output terminal of the voltage comparator U2C. The positive electrode of the diode D5 is connected to the power supply VCC through the resistor R19. The non-inverting input terminal of the voltage comparator U2C is connected to the thermistor module 10. The inverting input terminal of the voltage comparator U2C is connected to the R pole of the three-terminal voltage regulator D1.

[0030] As Figure 4 shown in the figure, the thermistor module 10 includes a resistor R12, a resistor R13, a resistor R14, a resistor R15, a thermistor RT1, a resistor R20, a resistor R21, a resistor R22, a resistor R23, and a thermistor RT2. One end of the resistor R13 is connected to the ground signal GND. The other end of the resistor R13 is connected to the non-inverting input terminal of the voltage comparator U1A. The other end of the resistor R13 is connected to one end of the resistor R14. The other end of the resistor R14 is connected to the non-inverting input terminal of the voltage comparator U1B. The other end of the resistor R14 is connected to one end of the resistor R12. The other end of the resistor R12 is connected to the non-inverting input terminal of the voltage comparator U1C. The other end of the resistor R12 is connected to one end of the thermistor RT1 through the resistor R15. The other end of the thermistor RT1 is connected to the power supply VCC. One end of the resistor R21 is connected to the power supply VCC. The other end of the majority resistor R21 is connected to one end of the resistor R22. The other end of the resistor R22 is connected to the non-inverting input terminal of the voltage comparator U2A. The other end of the resistor R22 is connected to one end of the resistor R20. The other end of the resistor R20 is connected to the non-inverting input terminal of the voltage comparator U2B. The other end of the resistor R20 is connected to one end of the resistor R23. The other end of the resistor R23 is connected to the non-inverting input terminal of the voltage comparator U2C. The other end of the resistor R23 is connected to the ground signal GND through the thermistor RT2.

[0031] As Figure 4As shown, the control module 3 includes a capacitor C1, a resistor R1, a resistor R10, a resistor R11, a resistor R16, a resistor R17, a transistor Q2, and a transistor Q3. One end of the capacitor C1 is connected to the NTC end of the AFE chip U1, and the other end of the capacitor C1 is connected to the ground signal GND. The resistor R1 is connected in parallel with the capacitor C1, one end of the resistor R10 is connected to the NTC end of the AFE chip U1, and the other end of the resistor R10 is connected to the collector of the transistor Q3. The emitter of the transistor Q3 is connected to the ground signal GND. The base of Q3 is connected to one end of the resistor R17, and the other end of the resistor R17 is connected to the cathode of the diode D7, the cathode of the diode D4, the cathode of the diode D3, and the cathode of the diode D8. One end of the resistor R11 is connected to the NTC end of the AFE chip U1, and the other end of the resistor R11 is connected to the collector of the transistor Q2. The emitter of the transistor Q2 is connected to the ground signal GND. The base of the transistor Q2 is connected to one end of the resistor R16, and the other end of the resistor R16 is connected to the cathode of the diode D2 and the cathode of the diode D5.

[0032] Working principle: Part 1: Several battery cells BT are connected in series as power sources, providing power and power conversion for each circuit. The AFE pure hardware protection solution collects temperature information according to the NTC pin and performs temperature protection related actions; Part 2: The power conversion module provides power VCC and reference level Vref; Part 3: The thermistor value of RT1 is compared with the voltage divider ratio formed by the resistors R13, R12, R14, and R15 and the reference Vref through comparators U1A, U1B, and U1C to generate a control signal, and the three states of temperature protection are identified respectively, which are: high discharge Temperature, charging high temperature, charging low temperature, the thermistor value of RT2 is respectively compared with the voltage divider ratio formed by resistors R21, R22, R20, and R23 and the reference Vref through comparators U1A, U1B, and U1C to generate a control signal, and the three states of temperature protection are identified respectively, namely: charging high temperature, charging low temperature, and discharging low temperature. Through the complementarity of the two groups, four states can be identified, namely: discharging high temperature, charging high temperature, charging low temperature, and discharging low temperature. Resistors R5, R6, R7, R8, R18, and R19 are pull-up resistors for the comparator signal output respectively; the fourth part is based on Figure 5 The temperature state of the control circuit is classified into three categories: 1. The state in which neither charging nor discharging is possible; 2. The state in which discharging but not charging is possible; 3. The state in which normal operation is possible is also the state in which the temperature protection is released. When the transistor Q3 is turned on, the state in which discharge is possible but charging is not allowed is formed; when the transistor Q2 is turned on or the transistor Q3 is turned on at the same time, the state in which neither discharge nor charging is allowed is formed.

[0033] Taking the discharge low-temperature protection at -15°C, charging low-temperature at 0°C, charging high-temperature at 50°C, and discharge high-temperature at 65°C as examples, to implement the corresponding temperature protection scheme, it can be found from the thermistor specification of RT1 that the RT value at -15°C is 55k, the RT value at 0°C is 27.7k, the RT value at 50°C is 3.53k, and the RT value at 65°C is 2.59k; the VCC configured in this figure is 5V and the Vref is 2.5V. The resistance values of the corresponding R13, R14, R12, and R15 can be obtained through calculation.

[0034] The calculation method of resistors R13, R14, R12, and R15 is to look up the resistance values corresponding to different temperatures in the thermistor specification and list the following engineering formulas according to Ohm's law:

[0035] ①. 5V * R13 / (R13 + R14 + R12 + R15 + RT) = 2.5V, where RT = the resistance value at the discharge high temperature. Looking up the RT table in the thermistor specification at 65°C, RT is 2.59k;

[0036] ②. 5V * (R13 + R14) / (R13 + R14 + R12 + R15 + RT) = 2.5V, where RT = the resistance value at the charging high temperature. Looking up the RT table in the thermistor specification at 50°C, RT is 3.53k;

[0037] ③. 5V * (R13 + R14 + R12) / (R13 + R14 + R12 + R15 + RT) = 2.5V;

[0038] ④. 5V * (R13 + R14 + R12 + R15) / (R13 + R14 + R12 + R15 + RT) = 2.5V.

[0039] Solve the resistance values of the corresponding R13, R14, R15, and R12 according to the above formulas.

[0040] When reaching the corresponding temperature, such as during high-temperature discharge, the levels at the non-inverting inputs of voltage comparators U1A, U1B, and U1C will be greater than 2.5V of the reference level Vref. At this time, the outputs of comparators U1A, U1B, and U1C will all output high levels, respectively controlling the conduction of transistors Q2 and Q3, making the circuit operate in a temperature state with both charge and discharge protection. When at high-temperature charging, the levels at the non-inverting inputs of voltage comparators U1A, U1B, and U1C and the levels at the non-inverting inputs of comparators U2A, U2B, and U2C will be greater than 2.5V of the reference level Vref. The outputs of voltage comparators U1A, U1B, and U1C and the outputs of comparators U2A, U2B, and U2C will all output high-level control signals, controlling the conduction of transistor Q3 to make the battery operate in a state of being charged protected and discharged unprotected. When at low-temperature charging, the levels at the non-inverting inputs of voltage comparators U1A, U1B, and U1C and the levels at the non-inverting inputs of comparators U2A, U2B, and U2C will be greater than 2.5V of the reference level Vref. The outputs of comparators U2A, U2B, and U2C will all output high-level control signals, controlling the conduction of Q3 to make it operate in a temperature state of being charged protected and discharged unprotected. When at low-temperature discharge, the levels at the non-inverting inputs of comparators U2A, U2B, and U2C will be greater than 2.5V of the reference level Vref. The outputs of comparators U2A, U2B, and U2C will all output high-level control signals, controlling the conduction of both transistors Q3 and Q2, making it operate in a temperature state with both charge and discharge protection. If it is not in any of the above four states, the outputs of comparators U2A, U2B, and U2C will not output high levels, and both transistors Q2 and Q3 will be in the cut-off state. At this time, it is in a normal working temperature state.

[0041] In the pure hardware BMS solution, the states of different working modes are divided by the temperature protection of the pure hardware, which are: normal working state, allowing discharge but not allowing charging state, not allowing charging and not allowing discharge state; 2. Still monitor the actual temperature in a pure hardware manner. When the temperature reaches the protected state, it will control the working state of the pure hardware solution without changing the logic; 3. In the way of comparators, the parameters of temperature protection are flexibly adjustable and not single and fixed; 4. In the way of state control, the number of detection ports of the thermistor can be increased, rather than only using the original number of detection ports of the BMS; 5. The protection function for low-temperature discharge is added. By adding 1 thermistor to add the protection function for low-temperature discharge, the temperature protection function of the pure hardware is made more perfect.

[0042] The present invention solves the problem that the temperature protection parameters in the pure hardware solution are single and fixed. The parameters of any protection temperature can be adjusted by calculating and replacing the resistance values ​​of the corresponding voltage-dividing resistors R13, R14, R12, R15, R21, R22 and R20; the present invention solves the problem that there is no discharge low temperature protection function in the pure hardware solution, and realizes the discharge low temperature protection function by adding thermistor RT2; the present invention can add multiple temperature detection channels, and more temperature thermistors can be extended and connected through the same solution, solving the problem of few temperature detection ports in the pure hardware solution; the present invention does not change the temperature protection control logic of the pure hardware, reasonably classifies the protection status of the pure hardware solution, and then controls it to be in the corresponding working state, so that the pure hardware BMS solution will not cause more complicated logic problems due to changes in temperature detection and temperature protection.

[0043] It should be noted that the above is only a specific embodiment of the present invention. Obviously, the present invention is not limited to the above embodiment, and there are many variations. In short, all variations that can be directly derived or associated with the content disclosed by ordinary technicians in this field should be considered as the protection scope of the present invention.

Claims

1. A circuit for solving the problem that the temperature protection parameters in a pure hardware BMS are fixed and single, characterized in that, It includes a battery module (1), an AFE chip U1, a power conversion module (2), a control module (3), a discharge high-temperature module (4), a first charging high-temperature module (5), a first charging low-temperature module (6), a second charging high-temperature module (7), a second charging low-temperature module (8), a discharge low-temperature module (9), a thermistor module (10), and a power supply VCC. The battery module (1) is formed by connecting a plurality of battery cells BT in series. The control module (3) and the battery module (1) are both connected to the AFE chip U1. The battery module (1), the discharge high-temperature module (4), the first charging high-temperature module (5), the first charging low-temperature module (6), the second charging high-temperature module (7), the second charging low-temperature module (8), and the discharge low-temperature module (9) are all connected to the power conversion module (2). The discharge high-temperature module (4), the first charging high-temperature module (5), the first charging low-temperature module (6), the second charging high-temperature module (7), the second charging low-temperature module (8), the discharge low-temperature module (9), and the thermistor module (10) are all connected to the control module (3). The discharge high-temperature module (4), the first charging high-temperature module (5), the first charging low-temperature module (6), the second charging high-temperature module (7), the second charging low-temperature module (8), the discharge low-temperature module (9) are all connected to the thermistor module (10). The power conversion module (2), the discharge high-temperature module (4), the first charging high-temperature module (5), the first charging low-temperature module (6), the second charging high-temperature module (7), the second charging low-temperature module (8), the discharge low-temperature module (9), and the thermistor module (10) are all connected to the power supply VCC; The discharge high-temperature module (4) includes a voltage comparator U1A, a diode D2, and a resistor R5. The first charging high-temperature module (5) includes a diode D7, a resistor R6, and a voltage comparator U1B. The first charging low-temperature module (6) includes a diode D4, a resistor R7, and a voltage comparator U1C. The second charging high-temperature module (7) includes a diode D3, a resistor R8, and a voltage comparator U2A. The second charging low-temperature module (8) includes a diode D8, a resistor R18, and a voltage comparator U2B. The discharge low-temperature module (9) includes a diode D5, a resistor R19, and a voltage comparator U2C; The thermistor module (10) includes a resistor R12, a resistor R13, a resistor R14, a resistor R15, a thermistor RT1, a resistor R20, a resistor R21, a resistor R22, a resistor R23, and a thermistor RT2. One end of the resistor R13 is connected to the ground signal GND, and the other end of the resistor R13 is connected to the non-inverting input terminal of the voltage comparator U1A. The other end of the resistor R13 is connected to one end of the resistor R14. The other end of the resistor R14 is connected to the non-inverting input terminal of the voltage comparator U1B. The other end of the resistor R14 is connected to one end of the resistor R12. The other end of the resistor R12 is connected to the non-inverting input terminal of the voltage comparator U1C. The other end of the resistor R12 is connected to one end of the thermistor RT1 through a resistor R15. The other end of the thermistor RT1 is connected to the power supply VCC. One end of the resistor R21 is connected to the power supply VCC, and the other end of the resistor R21 is connected to one end of the resistor R22. The other end of the resistor R22 is connected to the non-inverting input terminal of the voltage comparator U2A. The other end of the resistor R22 is connected to one end of the resistor R20. The other end of the resistor R20 is connected to the non-inverting input terminal of the voltage comparator U2B. The other end of the resistor R20 is connected to one end of the resistor R23. The other end of the resistor R23 is connected to the non-inverting input terminal of the voltage comparator U2C. The other end of the resistor R23 is connected to the ground signal GND through the thermistor RT2; The control module (3) includes a capacitor C1, a resistor R1, a resistor R10, a resistor R11, a resistor R16, a resistor R17, a triode Q2, and a triode Q3. One end of the capacitor C1 is connected to the NTC terminal of the AFE chip U1, and the other end of the capacitor C1 is connected to the ground signal GND. The resistor R1 is connected in parallel with the capacitor C1. One end of the resistor R10 is connected to the NTC terminal of the AFE chip U1, and the other end of the resistor R10 is connected to the collector of the triode Q3. The emitter of the triode Q3 is connected to the ground signal GND. The base of the triode Q3 is connected to one end of the resistor R17. The other end of the resistor R17 is connected to the negative electrodes of the diode D7, the diode D4, the diode D3, and the diode D8. One end of the resistor R11 is connected to the NTC terminal of the AFE chip U1, and the other end of the resistor R11 is connected to the collector of the triode Q2. The emitter of the triode Q2 is connected to the ground signal GND. The base of the triode Q2 is connected to one end of the resistor R16. The other end of the resistor R16 is connected to the negative electrodes of the diode D2 and the diode D5.

2. The circuit for solving the problem that the temperature protection parameters in the pure hardware BMS are fixed and single according to claim 1, wherein The power conversion module (2) includes a resistor R2, a resistor R3, a resistor R4, a resistor R9, a three-terminal voltage regulator D1, a diode D6, a triode Q1, and a power supply VCC. One end of the resistor R2 is connected to the battery module (1), and the other end of the resistor R2 is connected to the collector of the triode Q1. The collector of the triode Q1 is connected to the base of the triode Q1 through the resistor R3. The base of the triode Q1 is connected to the ground signal through the diode D6. The emitter of the triode Q1 is connected to the K pole of the three-terminal voltage regulator D1. The A pole of the three-terminal voltage regulator D1 is connected to the ground signal GND. The R pole of the three-terminal voltage regulator D1 is connected to the ground signal GND through the resistor R9. The R pole of the three-terminal voltage regulator D1 is connected to the power supply VCC through the resistor R4. The R pole of the three-terminal voltage regulator D1 outputs a reference level Vref.

3. The circuit for solving the problem that the temperature protection parameters in the pure hardware BMS are fixed and single according to claim 2, characterized in that In the discharge high-temperature module (4), the negative pole of the diode D2 is connected to the control module (3), the positive pole of the diode D2 is connected to the output terminal of the voltage comparator U1A, the positive pole of the diode D2 is connected to the power supply VCC through the resistor R5, the non-inverting input terminal of the voltage comparator U1A is connected to the thermistor module (10), and the inverting input terminal of the voltage comparator U1A is connected to the R pole of the three-terminal voltage regulator D1.

4. The circuit for solving the problem that the temperature protection parameters in the pure hardware BMS are fixed and single according to claim 2, characterized in that In the discharge low-temperature module (9), the positive pole of the diode D5 is connected to the output terminal of the voltage comparator U2C, the positive pole of the diode D5 is connected to the power supply VCC through the resistor R19, the non-inverting input terminal of the voltage comparator U2C is connected to the thermistor module (10), and the inverting input terminal of the voltage comparator U2C is connected to the R pole of the three-terminal voltage regulator D1.

5. The circuit for solving the problem that the temperature protection parameters in the pure hardware BMS are fixed and single according to claim 3, wherein In the first charging high-temperature module (5), the negative pole of the diode D7 is connected to the control module (3), the positive pole of the diode D7 is connected to the output terminal of the voltage comparator U1B, the positive pole of the diode D7 is connected to the power supply VCC through the resistor R6, the non-inverting input terminal of the voltage comparator U1B is connected to the thermistor module (10), and the inverting input terminal of the voltage comparator U1B is connected to the R pole of the three-terminal voltage regulator D1.

6. The circuit for solving the problem that the temperature protection parameters in the pure hardware BMS are fixed and single according to claim 5, characterized in that In the first charging low-temperature module (6), the positive pole of the diode D4 is connected to the output terminal of the voltage comparator U1C, the positive pole of the diode D4 is connected to the power supply VCC through the resistor R7, the non-inverting input terminal of the voltage comparator U1C is connected to the thermistor module (10), and the inverting input terminal of the voltage comparator U1C is connected to the R pole of the three-terminal voltage regulator D1.

7. The circuit for solving the problem that the temperature protection parameters in the pure hardware BMS are fixed and single according to claim 6, characterized in that, In the second charging high-temperature module (7), the positive pole of the diode D3 is connected to the output terminal of the voltage comparator U2A, the positive pole of the diode D3 is connected to the power supply VCC through the resistor R8, the non-inverting input terminal of the voltage comparator U2A is connected to the thermistor module (10), and the inverting input terminal of the voltage comparator U2A is connected to the R pole of the three-terminal voltage regulator D1.

8. A circuit for solving the problem that the temperature protection parameters in a pure hardware BMS are fixed and single, as claimed in claim 7, wherein In the second charging and low-temperature module (8), the positive electrode of the diode D8 is connected to the output terminal of the voltage comparator U2B. The positive electrode of the diode D8 is connected to the power supply VCC through the resistor R18. The non-inverting input terminal of the voltage comparator U2B is connected to the thermistor module (10). The inverting input terminal of the voltage comparator U2B is connected to the R pole of the three-terminal voltage regulator D1.

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