Detection circuit of battery pack

Abstract

The utility model relates to the technical field of battery detection, and discloses a detection circuit of a battery pack, which is high in reliability and stable, and comprises a first voltage detection module (101), a second voltage detection module (102) and a main control module (300), the first voltage detection module (101) is used for acquiring a first voltage signal, the second voltage detection module (102) is used for receiving the first voltage signal and the second voltage signal, and the main control module (300) is used for receiving the first voltage signal and the second voltage signal. And the charging signal of the first battery pack or the second battery pack is adjusted according to the voltage value of the input first voltage signal or the second voltage signal.

Description

Technical Field

[0001] The utility model relates to the technical field of battery detection, and more specifically to a detection circuit for a battery pack. Background Art

[0002] In the field of new energy vehicles, the voltage, current, temperature and other parameters of the battery pack are generally detected through sensor modules. The sensor modules send the detected data to the main control module to monitor and manage the working status of the battery pack, such as collecting parameters such as voltage and current to achieve real-time monitoring of the battery status.

[0003] However, the detection circuit of the existing battery pack usually uses a single electrolytic module to detect the battery pack (usually composed of at least two groups of battery packs connected). Although the use of a single detection module can reduce the cost of the detection circuit, the single electrolytic module will increase the voltage borne by the electronic components, and long-term use will reduce the service life of the electronic components. In addition, a single detection module cannot monitor whether the voltages of the two groups of batteries are balanced, and overcharging or undercharging will damage the battery pack, resulting in a decrease in the capacity of the battery pack and a shortened life. Utility Model Content

[0004] The technical problem to be solved by the present invention is that, in view of the defect that the above-mentioned single detection module in the prior art cannot monitor whether the voltages of two battery groups are balanced, and overcharging or undercharging will damage the battery pack, resulting in a decrease in the capacity of the battery pack and a shortened life, a detection circuit for the battery pack with high reliability and stability is provided.

[0005] The technical solution adopted by the utility model to solve the technical problem is: construct a battery pack detection circuit, which has:

[0006] A first voltage detection module, which is configured in the detection circuit, has an input end connected to an output end of the first battery pack, and is used to obtain a first voltage signal;

[0007] A second voltage detection module, whose input end is connected to the output end of the second battery pack and is used to obtain a second voltage signal;

[0008] A main control module, whose first signal input terminal is connected to the output terminal of the first voltage detection module, is used to receive the first voltage signal,

[0009] The second signal input terminal of the main control module is connected to the output terminal of the second voltage detection module for receiving the second voltage signal.

[0010] The main control module adjusts the charging signal of the first battery pack or the second battery pack according to the voltage value of the input first voltage signal or the second voltage signal.

[0011] In some embodiments, the first voltage detection module includes at least a first resistor, a second resistor, a sixth resistor, a seventh resistor, and a first operational amplifier.

[0012] The first resistor is connected in series with the second resistor.

[0013] The sixth resistor is connected in series with the seventh resistor, wherein:

[0014] One end of the first resistor is connected to one end of the first battery pack to receive a voltage signal output by the first battery pack.

[0015] One end of the sixth resistor is connected to the other end of the first battery pack,

[0016] One end of the second resistor is coupled to the non-inverting end of the first operational amplifier.

[0017] One end of the seventh resistor is coupled to the inverting end of the first operational amplifier.

[0018] The output end of the first operational amplifier is connected to the first signal input end of the main control module.

[0019] In some embodiments, the first voltage detection module further includes a third resistor and a first capacitor connected in parallel.

[0020] The third resistor and one end of the first capacitor are connected to the non-inverting end of the first operational amplifier.

[0021] The other ends of the third resistor and the first capacitor are connected to a common end.

[0022] In some embodiments, the first voltage detection module further includes a fourth resistor and a third capacitor connected in parallel.

[0023] One end of the fourth resistor and the third capacitor is connected to the inverting end of the first operational amplifier.

[0024] The other ends of the fourth resistor and the third capacitor are connected to the output end of the first operational amplifier.

[0025] In some embodiments, the second voltage detection module at least includes an eighth resistor, a ninth resistor, a thirteenth resistor, a fourteenth resistor and a second operational amplifier.

[0026] The eighth resistor is connected in series with the ninth resistor,

[0027] The thirteenth resistor is connected in series with the fourteenth resistor, wherein:

[0028] One end of the eighth resistor is connected to one end of the second battery pack, and is used to receive a voltage signal output by the second battery pack.

[0029] One end of the thirteenth resistor is connected to the other end of the second battery pack,

[0030] One end of the ninth resistor is coupled to the non-inverting end of the second operational amplifier.

[0031] One end of the fourteenth resistor is coupled to the inverting end of the second operational amplifier.

[0032] The output end of the second operational amplifier is connected to the second signal input end of the main control module.

[0033] In some embodiments, the second voltage detection module further includes a tenth resistor and a fifth capacitor connected in parallel.

[0034] One end of the tenth resistor and the fifth capacitor is connected to the non-inverting terminal of the second operational amplifier.

[0035] The other ends of the tenth resistor and the fifth capacitor are connected to a common end.

[0036] In some embodiments, the second voltage detection module further includes an eleventh resistor and a seventh capacitor connected in parallel.

[0037] The eleventh resistor and one end of the seventh capacitor are connected to the inverting end of the second operational amplifier.

[0038] The other ends of the eleventh resistor and the seventh capacitor are connected to the output end of the second operational amplifier.

[0039] In some embodiments, a current detection circuit is further included, whose input terminal is connected to the power supply output terminal, and is used to obtain a charging current signal when the first battery pack or the second battery pack is charged.

[0040] The output end of the current detection circuit is connected to the third signal input end of the main control module.

[0041] In some embodiments, the current detection circuit includes a third operational amplifier,

[0042] The non-inverting terminal of the third operational amplifier is connected to the output terminal of the power supply 1 through the sixteenth resistor.

[0043] The inverting terminal of the third operational amplifier is connected to the other output terminal of the power supply through the seventeenth resistor.

[0044] The output end of the third operational amplifier is connected to the third signal input end of the main control module.

[0045] In the detection circuit of the battery pack described in the utility model, a first voltage detection module, a second voltage detection module and a main control module are included for obtaining a first voltage signal, wherein the main control module is used to receive the first voltage signal and the second voltage signal, and adjust the charging signal of the first battery pack or the second battery pack according to the voltage value of the input first voltage signal or the second voltage signal. Compared with the prior art, by setting two or more voltage detection modules to detect the voltage of each battery pack in the battery pack and feed back to the main control module, the main control module adjusts the charging voltage / current of each battery pack according to the feedback voltage signal to ensure that the voltage of each battery pack remains balanced, which can effectively solve the problem that a single detection module cannot monitor whether the voltages of two battery packs are balanced, and the battery pack is damaged when a battery pack is overcharged or undercharged. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0047] Figure 1 This is a circuit schematic diagram of an embodiment of a voltage detection module provided by the utility model;

[0048] Figure 2 This is a circuit schematic diagram of an embodiment of a current detection circuit provided by the utility model;

[0049] Figure 3 This is a circuit schematic diagram of an embodiment of a main control module provided by the utility model. DETAILED DESCRIPTION

[0050] In order to have a clearer understanding of the technical features, purposes and effects of the present utility model, the specific implementation methods of the present utility model are now described in detail with reference to the accompanying drawings.

[0051] like Figure 1-Figure 3 As shown, in the first embodiment of the detection circuit of the battery pack of the utility model, the detection circuit (100, 200, 300) of the battery pack includes a voltage detection module 100, a current detection circuit 200 and a main control module 300,

[0052] The voltage detection module 100 is used to detect the voltage signal when the battery pack is charging;

[0053] The current detection circuit 200 is used to detect the current signal when the battery pack is charging;

[0054] The main control module 300 serves as the control core of the detection circuit, and has the functions of multiple threshold signals, data calculation, signal processing, signal comparison, and outputting PWM signals.

[0055] The voltage detection module 100 includes a first voltage detection module 101 and a second voltage detection module 102.

[0056] The main control module 300 at least includes a main controller U301;

[0057] The first voltage detection module 101 is used to obtain the voltage signal of the first battery pack BT1.

[0058] The second voltage detection module 101 is used to obtain the voltage signal of the second battery pack BT2;

[0059] Specifically, the first voltage detection module 101 is configured in the detection circuit, and its input end is connected to the output end of the first battery pack BT1, for obtaining a first voltage signal when the first battery pack BT1 is charged, and outputting the first voltage signal to the main control module 300;

[0060] The input end of the second voltage detection module 102 is connected to the output end of the second battery pack BT2, and is used to obtain a second voltage signal when the second battery pack BT2 is charged, and output the second voltage signal to the main control module 300;

[0061] The first signal input terminal of the main control module 300 is connected to the output terminal of the first voltage detection module 101, and is used to receive a first voltage signal, process the first voltage signal (such as analog-to-digital conversion), and compare it with a first threshold signal built therein, and output a control signal according to the comparison result between the first voltage signal and the first threshold signal to adjust the duty cycle of the PWM signal, thereby controlling the charging current of the first battery pack BT1;

[0062] Furthermore, the second signal input terminal of the main control module 300 is connected to the output terminal of the second voltage detection module 102, and is used to receive the second voltage signal, process the second voltage signal (such as analog-to-digital conversion), and then compare it with the built-in second threshold signal, and output a control signal according to the comparison result between the second voltage signal and the second threshold signal to adjust the duty cycle of the PWM signal, thereby controlling the charging current of the second battery pack BT2;

[0063] Specifically, the main control module 300 may be configured to receive a voltage value of the first voltage signal or the second voltage signal according to the voltage value of the first voltage signal or the second voltage signal.

[0064] According to the comparison result between the voltage value of the input first voltage signal or the second voltage signal and the threshold signal, the duty cycle of the output PWM signal is adjusted, thereby adjusting the charging signal of the first battery pack BT1 or the second battery pack BT2 to ensure / maintain the voltage balance of the battery pack, so as to improve the safety and reliability of the battery pack operation.

[0065] By using the present technical solution, two or more voltage detection modules are provided to detect the voltage of each battery pack in the battery pack and feed back the voltage to the main control module 300. The main control module 300 adjusts the charging voltage / current of each battery pack according to the feedback voltage signal to ensure that the voltage of each battery pack remains balanced. This can effectively solve the problem that a single detection module cannot monitor whether the voltages of two battery groups are balanced, and the battery pack is damaged when a battery pack is overcharged or undercharged.

[0066] In some embodiments, Figure 1 As shown, in order to ensure the reliability of obtaining the constant voltage signal, a first resistor R101, a second resistor R102, a sixth resistor R106, a seventh resistor R107 and a first operational amplifier U1A may be provided in the first voltage detection module 101.

[0067] The first resistor R101 and the second resistor R102 are sampling resistors, and their resistance values ​​can be selected as 1M.

[0068] The first operational amplifier U1A has the function of signal amplification;

[0069] Specifically, the first resistor R101 and the second resistor R102 are connected in series.

[0070] The sixth resistor R106 and the seventh resistor R107 are connected in series, wherein:

[0071] One end of the first resistor R101 is connected to one end of the first battery pack BT1, and is used to receive a voltage signal output by the first battery pack BT1.

[0072] One end of the sixth resistor R106 is connected to the other end of the first battery pack BT1.

[0073] One end of the second resistor R102 is coupled to the non-inverting end (corresponding to pin 2) of the first operational amplifier U1A. The voltage signal output by the first battery pack BT1 is divided by the first resistor R101 and the second resistor R102 and then input into the first operational amplifier U1A.

[0074] One end of the seventh resistor R107 is coupled to the inverting end (corresponding to pin 3) of the first operational amplifier U1A. The voltage signal output by the first battery pack BT1 is divided by the sixth resistor R106 and the seventh resistor R107 and then input to the inverting end of the first operational amplifier U1A.

[0075] The output end of the first operational amplifier U1A (corresponding to pin 4) is connected to the first signal input end of the main control module 300 through the fifth resistor R105. The first operational amplifier U1A amplifies the voltage signal input by the first battery pack BT1 and inputs it into the first signal input end (corresponding to pin 7) of the main controller U301 (belonging to the main control module 300).

[0076] In some embodiments, Figure 1 As shown, the first voltage detection module 101 further includes a third resistor R103 and a first capacitor C101 connected in parallel, wherein the resistance value of the third resistor R103 is selected to be 20K.

[0077] Specifically, one end of the third resistor R103 and one end of the first capacitor C101 are connected to the in-phase terminal (corresponding to pin 2) of the first operational amplifier U1A.

[0078] The other end of the third resistor R103 and the other end of the first capacitor C101 are connected to the common end.

[0079] In some embodiments, Figure 1 As shown, the first voltage detection module 101 further includes a fourth resistor R104 and a third capacitor C103 connected in parallel, wherein the resistance value of the fourth resistor R104 is selected to be 20K.

[0080] Specifically, one end of the fourth resistor R104 and one end of the third capacitor C103 are connected to the inverting end (corresponding to pin 3) of the first operational amplifier U1A.

[0081] The other ends of the fourth resistor R104 and the third capacitor C103 are connected to the output end (corresponding to pin 4) of the first operational amplifier U1A.

[0082] In some embodiments, Figure 1 As shown, in order to ensure the reliability of obtaining the constant voltage signal, an eighth resistor R108, a ninth resistor R109, a thirteenth resistor R113, a fourteenth resistor R114 and a second operational amplifier U1B can be set in the second voltage detection module 102, wherein the resistance values ​​of the eighth resistor R108 and the ninth resistor R109 are selected to be 1M,

[0083] The second operational amplifier U1B has the function of signal amplification;

[0084] Specifically, the eighth resistor R108 and the ninth resistor R109 are connected in series.

[0085] The thirteenth resistor R113 and the fourteenth resistor R114 are connected in series, wherein:

[0086] One end of the eighth resistor R108 is connected to one end of the second battery pack BT2, and is used to receive a voltage signal output by the second battery pack BT2.

[0087] One end of the thirteenth resistor R113 is connected to the other end of the second battery pack BT2.

[0088] One end of the ninth resistor R109 is coupled to the non-inverting terminal (corresponding to pin 6) of the second operational amplifier U1B. The voltage signal output by the second battery pack BT2 is divided by the eighth resistor R108 and the ninth resistor R109, and then input to the non-inverting terminal (corresponding to pin 6) of the second operational amplifier U1B.

[0089] One end of the fourteenth resistor R114 is coupled to the inverting end (corresponding to pin 5) of the second operational amplifier U1B. The voltage signal output by the second battery pack BT2 is divided by the thirteenth resistor R113 and the fourteenth resistor R114 and then input to the inverting end (corresponding to pin 5) of the second operational amplifier U1B.

[0090] The output end (corresponding to pin 7) of the second operational amplifier U1B is connected to the second signal input end of the main control module 300 through the twelfth resistor R112. The second operational amplifier U1B amplifies the voltage signal input from the second battery pack BT2 and inputs it into the second signal input end (corresponding to pin 8) of the main controller U301 (belonging to the main control module 300).

[0091] In some embodiments, Figure 1 As shown, the second voltage detection module 102 further includes a tenth resistor R110 and a fifth capacitor C105 connected in parallel, wherein the resistance value of the tenth resistor R110 is selected to be 20K.

[0092] Specifically, one end of the tenth resistor R110 and the fifth capacitor C105 is connected to the in-phase terminal (corresponding to pin 6) of the second operational amplifier U1B.

[0093] The other ends of the tenth resistor R110 and the fifth capacitor C105 are connected to the common end.

[0094] In some embodiments, Figure 1 As shown, the second voltage detection module 102 further includes an eleventh resistor R111 and a seventh capacitor C107 connected in parallel, wherein the resistance value of the eleventh resistor R111 is selected to be 20K.

[0095] Specifically, one end of the eleventh resistor R111 and the seventh capacitor C107 is connected to the inverting end (corresponding to pin 5) of the second operational amplifier U1B.

[0096] The other ends of the eleventh resistor R111 and the seventh capacitor C107 are connected to the output end (corresponding to pin 7) of the second operational amplifier U1B.

[0097] In some embodiments, Figure 2 As shown, in order to improve the balance of the charging current, a current detection circuit 200 can be provided in the circuit, which is used to detect the charging current signal of the battery pack;

[0098] Specifically, the input end of the current detection circuit 200 is connected to the power output end, and is used to obtain a charging current signal when the first battery pack BT1 or the second battery pack BT2 is charged.

[0099] The output end of the current detection circuit 200 is connected to the third signal input end of the main control module 300, and outputs the acquired charging current signal to the third signal input end (corresponding to pin 5) of the input main controller U301 (belonging to the main control module 300).

[0100] In some embodiments, Figure 2 As shown, the current detection circuit 200 includes a third operational amplifier U2A, which has the function of signal amplification;

[0101] Specifically, the in-phase terminal (corresponding to pin 2) of the third operational amplifier U2A is connected to the first output terminal (L-IN) of the power supply through the sixteenth resistor R202.

[0102] The inverting terminal (corresponding to pin 3) of the third operational amplifier U2A is connected to the other output terminal (N-IN) of the power supply through the seventeenth resistor R203.

[0103] The output end (corresponding to pin 4) of the third operational amplifier U2A is connected to the third signal input end (corresponding to pin 5) of the main controller U301 (belonging to the main control module 300) through the nineteenth resistor R205, and the charging current signal output by the third operational amplifier U2A is input into the main controller U301 through the nineteenth resistor R205.

[0104] like Figure 1 As shown, the diodes (D101, D102, D104, D105, D106, D107, D109 and D110) at the input end are used as input voltage clamps to ensure the reliability of the electronic components.

[0105] The embodiments of the utility model are described above in conjunction with the accompanying drawings, but the utility model is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the utility model, ordinary technicians in this field can also make many forms without departing from the scope of protection of the utility model and the claims, which all fall within the protection of the utility model.

Claims

1. A detection circuit for a battery pack, characterized in that: have: A first voltage detection module, which is configured in the detection circuit, has an input end connected to an output end of the first battery pack, and is used to obtain a first voltage signal; A second voltage detection module, whose input end is connected to the output end of the second battery pack and is used to obtain a second voltage signal; A main control module, whose first signal input terminal is connected to the output terminal of the first voltage detection module, is used to receive the first voltage signal, The second signal input terminal of the main control module is connected to the output terminal of the second voltage detection module for receiving the second voltage signal. The main control module adjusts the charging signal of the first battery pack or the second battery pack according to the voltage value of the input first voltage signal or the second voltage signal.

2. The detection circuit of the battery pack according to claim 1, characterized in that: The first voltage detection module at least includes a first resistor, a second resistor, a sixth resistor, a seventh resistor and a first operational amplifier. The first resistor is connected in series with the second resistor. The sixth resistor is connected in series with the seventh resistor, wherein: One end of the first resistor is connected to one end of the first battery pack to receive a voltage signal output by the first battery pack. One end of the sixth resistor is connected to the other end of the first battery pack, One end of the second resistor is coupled to the non-inverting end of the first operational amplifier. One end of the seventh resistor is coupled to the inverting end of the first operational amplifier. The output end of the first operational amplifier is connected to the first signal input end of the main control module.

3. The detection circuit of the battery pack according to claim 2, characterized in that: The first voltage detection module also includes a third resistor and a first capacitor connected in parallel, The third resistor and one end of the first capacitor are connected to the non-inverting end of the first operational amplifier. The other ends of the third resistor and the first capacitor are connected to a common end.

4. The detection circuit of the battery pack according to claim 3, characterized in that: The first voltage detection module further includes a fourth resistor and a third capacitor connected in parallel, One end of the fourth resistor and the third capacitor is connected to the inverting end of the first operational amplifier. The other ends of the fourth resistor and the third capacitor are connected to the output end of the first operational amplifier.

5. The detection circuit of the battery pack according to claim 1, characterized in that: The second voltage detection module at least includes an eighth resistor, a ninth resistor, a thirteenth resistor, a fourteenth resistor and a second operational amplifier. The eighth resistor is connected in series with the ninth resistor, The thirteenth resistor is connected in series with the fourteenth resistor, wherein: One end of the eighth resistor is connected to one end of the second battery pack, and is used to receive a voltage signal output by the second battery pack. One end of the thirteenth resistor is connected to the other end of the second battery pack, One end of the ninth resistor is coupled to the non-inverting end of the second operational amplifier. One end of the fourteenth resistor is coupled to the inverting end of the second operational amplifier. The output end of the second operational amplifier is connected to the second signal input end of the main control module.

6. The detection circuit of the battery pack according to claim 5, characterized in that: The second voltage detection module further includes a tenth resistor and a fifth capacitor connected in parallel, One end of the tenth resistor and the fifth capacitor is connected to the non-inverting terminal of the second operational amplifier. The other ends of the tenth resistor and the fifth capacitor are connected to a common end.

7. The detection circuit of the battery pack according to claim 5 or 6, characterized in that: The second voltage detection module further includes an eleventh resistor and a seventh capacitor connected in parallel, The eleventh resistor and one end of the seventh capacitor are connected to the inverting end of the second operational amplifier. The other ends of the eleventh resistor and the seventh capacitor are connected to the output end of the second operational amplifier.

8. The detection circuit of the battery pack according to claim 7, characterized in that: It also includes a current detection circuit, whose input end is connected to the power output end, and is used to obtain a charging current signal when the first battery pack or the second battery pack is charged. The output end of the current detection circuit is connected to the third signal input end of the main control module.

9. The detection circuit of the battery pack according to claim 8, characterized in that: The current detection circuit includes a third operational amplifier, The non-inverting terminal of the third operational amplifier is connected to the output terminal of the power supply 1 through the sixteenth resistor. The inverting terminal of the third operational amplifier is connected to the other output terminal of the power supply through the seventeenth resistor. The output end of the third operational amplifier is connected to the third signal input end of the main control module.

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