Load control circuit of double-battery system

Abstract

The utility model discloses a load control circuit for a double-battery system, and the circuit comprises a first battery module which comprises a first drive unit, a first battery fault isolation unit, and a first battery which are connected in sequence; the second battery module comprises a second driving unit, a second battery fault isolation unit and a second battery which are connected in sequence; the sampling and protecting module comprises a first voltage acquisition unit, a second voltage acquisition unit, an output voltage acquisition unit and an output current acquisition unit; the input end of the MCU module is respectively connected with the first voltage acquisition unit, the second voltage acquisition unit, the output voltage acquisition unit and the output current acquisition unit, and the output end of the MCU module is respectively connected with the first driving unit and the second driving unit; and a sampling resistor. According to the utility model, battery switching is managed through the MOS loop, and microsecond switching is achieved; and over-current protection does not need to replace fuses, thereby reducing maintenance time and maintenance cost.

Description

Technical Field

[0001] The utility model relates to a battery management system, in particular to a dual-battery system load control circuit. Background Art

[0002] The battery management system (BMS) is a device used to monitor and manage batteries, which can ensure the stability and safety of the batteries.

[0003] Ships need dual batteries in control terminals, heating and lighting systems, and engines. Existing battery management systems often use relays for dual battery system switching management, which has a slow switching speed and causes load power failure during the switching process. For overcurrent protection, fuses are often used. When the load is short-circuited or overloaded, the fuse will blow and the fuse must be replaced before it can be used. This is inconvenient whether it is used in electric vehicles or ships. Utility Model Content

[0004] The utility model aims to solve the problem in the prior art that the battery switching is slow and the overcurrent protection needs to replace the fuse before the battery can be used continuously.

[0005] The technical solution adopted by the utility model to solve the technical problem is: to provide a dual battery system load control circuit, including:

[0006] A first battery module includes a first drive unit, a first battery fault isolation unit and a first battery connected in sequence;

[0007] A second battery module includes a second drive unit, a second battery fault isolation unit and a second battery connected in sequence;

[0008] A sampling resistor, one end of which is connected to the first battery fault isolation unit and the second battery fault isolation unit respectively, and the other end of which is connected to the load;

[0009] The sampling and protection module includes a first voltage acquisition unit, a second voltage acquisition unit, an output voltage acquisition unit and an output current acquisition unit, wherein the first voltage acquisition unit is connected to the first battery, the second voltage acquisition unit is connected to the second battery, the output voltage acquisition unit is connected to one end of the sampling resistor connected to the load, and the output current acquisition unit is connected to both ends of the sampling resistor;

[0010] The MCU module has an input end connected to the first voltage acquisition unit, the second voltage acquisition unit, the output voltage acquisition unit and the output current acquisition unit respectively, and an output end connected to the first drive unit and the second drive unit respectively.

[0011] Preferably, the first battery and the second battery share a common negative electrode.

[0012] Preferably, the first battery fault isolation unit includes a first MOS tube and a second MOS tube, the source of the first MOS tube is connected to the source of the second MOS tube, the gate of the first MOS tube is connected to the gate of the second MOS tube, the drain of the first MOS tube is connected to the positive electrode of the first battery, and the drain of the second MOS tube is connected to the sampling resistor;

[0013] The second battery fault isolation unit includes a third MOS tube and a fourth MOS tube, the source of the third MOS tube is connected to the source of the fourth MOS tube, the gate of the third MOS tube is connected to the gate of the fourth MOS tube, the drain of the third MOS tube is connected to the positive electrode of the second battery, and the drain of the fourth MOS tube is connected to the sampling resistor.

[0014] Preferably, the MCU module includes a first IC chip, the input end of the first IC chip is respectively connected to the first voltage acquisition unit, the second voltage acquisition unit, the output voltage acquisition unit and the output current acquisition unit of the sampling and protection module, and the output end of the first IC chip is respectively connected to the first drive unit and the first drive unit.

[0015] Preferably, the first voltage acquisition unit includes a twenty-seventh resistor, a thirtieth resistor and a fifteenth capacitor, one end of the twenty-seventh resistor is connected to the positive electrode of the first battery, the other end of the twenty-seventh resistor is respectively connected to the MCU module, one end of the fifteenth capacitor, and one end of the thirtieth resistor, the other end of the fifteenth capacitor is connected to the negative electrode of the battery, and the other end of the thirtieth resistor is connected to the negative electrode of the battery.

[0016] Preferably, the second voltage acquisition unit includes a thirty-third resistor, a thirty-seventh resistor and a seventeenth capacitor, one end of the thirty-third resistor is connected to the positive electrode of the second battery, the other end of the thirty-third resistor is respectively connected to the MCU module, one end of the seventeenth capacitor and one end of the thirty-seventh resistor, the other end of the seventeenth capacitor is connected to the negative electrode of the battery, and the other end of the thirty-seventh resistor is connected to the negative electrode of the battery.

[0017] Preferably, the output voltage acquisition unit includes a thirty-ninth resistor, a fortieth resistor and a twentieth capacitor, one end of the thirty-ninth resistor is connected to one end of the sampling resistor connected to the load, and the other end of the thirty-ninth resistor is respectively connected to the MCU module, one end of the twentieth capacitor and one end of the fortieth resistor; the other end of the twentieth capacitor is connected to the negative electrode of the battery, and the other end of the fortieth resistor is connected to the negative electrode of the battery.

[0018] Preferably, the output current acquisition unit comprises a first chip, an input end of the first chip is connected to two ends of the sampling resistor, and an output end of the first chip is connected to the MCU module.

[0019] The utility model has the following beneficial effects:

[0020] (1) The load output circuit is controlled by MOS tube to achieve microsecond-level fast opening and closing, and the load does not lose power during the battery power supply switching process;

[0021] (2) When a short circuit or overload occurs in the load output, the fault isolation unit can quickly protect the battery and load. After protection, the MOS is disconnected and the load output is turned off. There is no need to replace the fuse, which reduces maintenance time and maintenance costs.

[0022] (3) Monitor the fault isolation unit by the load output voltage to see if there is any abnormality.

[0023] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited to the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural diagram of an embodiment of the utility model;

[0025] Figure 2 A circuit diagram of a first fault isolation unit and a second fault isolation unit according to an embodiment of the utility model;

[0026] Figure 3 This is a circuit diagram of a sampling and protection module according to an embodiment of the utility model;

[0027] Figure 4 This is a circuit diagram of the MCU module of an embodiment of the utility model;

[0028] Figure 5 This is a circuit diagram of a first driving unit according to an embodiment of the utility model;

[0029] Figure 6 This is a circuit diagram of a second driving unit according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0030] See also Figure 1 As shown, it is a structural diagram of an embodiment of the utility model, including

[0031] A first battery module 1, comprising a first drive unit 11, a first battery fault isolation unit 12 and a first battery 13 connected in sequence;

[0032] The second battery module 2 includes a second driving unit 21, a second battery fault isolation unit 22 and a second battery 23 connected in sequence;

[0033] The sampling and protection module 3 includes a first voltage acquisition unit 31, a second voltage acquisition unit 32, an output voltage acquisition unit 33 and an output current acquisition unit 34, wherein the first voltage acquisition unit 31 is connected to the first battery 13, the second voltage acquisition unit 32 is connected to the second battery 23, the output voltage acquisition unit 33 is connected to one end of the sampling resistor connected to the load, and the output current acquisition unit 34 is connected to both ends of the sampling resistor;

[0034] The MCU module 4 has an input end connected to the first voltage acquisition unit 31, the second voltage acquisition unit 32, the output voltage acquisition unit 33 and the output current acquisition unit 34, respectively, and an output end connected to the first drive unit 11 and the second drive unit 21, respectively;

[0035] The sampling resistor 5 has one end connected to the first battery fault isolation unit 12 and the second battery fault isolation unit 22 respectively, and the other end connected to the load 6 .

[0036] For details, see Figure 2 As shown, it is a circuit diagram of the first fault isolation unit 12 and the second fault isolation unit 22 of the embodiment of the utility model. The first battery fault isolation unit 12 includes a second MOS tube Q2 and a third MOS tube Q3, the source of the second MOS tube Q2 is connected to the source of the third MOS tube Q3, the gate of the second MOS tube Q2 is connected to the gate of the third MOS tube Q3, the drain of the second MOS tube Q2 is connected to the positive electrode of the first battery 13, and the drain of the third MOS tube Q3 is connected to the sampling resistor 5;

[0037] The second battery fault isolation unit 22 includes a sixth MOS transistor Q6 and a seventh MOS transistor Q7, wherein the source of the sixth MOS transistor Q6 is connected to the source of the seventh MOS transistor Q7, the gate of the sixth MOS transistor Q6 is connected to the gate of the seventh MOS transistor Q7, the drain of the sixth MOS transistor Q6 is connected to the positive electrode of the second battery 23, and the drain of the seventh MOS transistor Q7 is connected to the sampling resistor 5.

[0038] For details, see Figure 3 , which is a circuit diagram of a sampling and protection module according to an embodiment of the present utility model, the sampling and protection module 3 includes a first voltage acquisition unit 31 , a second voltage acquisition unit 32 , an output voltage acquisition unit 33 and an output current acquisition unit 34 .

[0039] The first voltage acquisition unit 31 includes a twenty-seventh resistor R27, a thirtieth resistor R30 and a fifteenth capacitor C15, one end of the twenty-seventh resistor R27 is connected to the positive electrode of the first battery, the other end of the twenty-seventh resistor R27 is connected to the MCU module to output the voltage of the first battery, and the other end of the twenty-seventh resistor R27 is also connected to the negative electrode of the battery through the fifteenth capacitor C15 and the thirtieth resistor R30.

[0040] The second voltage acquisition unit 32 includes a thirty-third resistor R33, a thirty-seventh resistor R37 and a seventeenth capacitor C17, one end of the thirty-third resistor R33 is connected to the positive electrode of the second battery, the other end of the thirty-third resistor R33 is connected to the MCU module to output the voltage of the second battery, and the other end of the thirty-third resistor R33 is also connected to the negative electrode of the battery through one end of the seventeenth capacitor C17 and the thirty-seventh resistor R37.

[0041] The output voltage acquisition unit 33 includes a thirty-ninth resistor R39, a fortieth resistor R40 and a twentieth capacitor C20, one end of the thirty-ninth resistor R39 is connected to one end of the sampling resistor connected to the load, and the other end of the thirty-ninth resistor R39 is connected to the MCU module to output the load output voltage; the other end of the thirty-ninth resistor R39 is also connected to the negative electrode of the battery through the twentieth capacitor C20 and the fortieth resistor R40.

[0042] The output current acquisition unit 34 includes a first chip U1, a first pin of the first chip U1 is connected to one end of the twelfth resistor R12, the other end of the twelfth resistor R12 is connected to the MCU module to output the load current, the other end of the twelfth resistor R12 is also connected to one end of the eleventh capacitor C11, and the other end of the eleventh capacitor C11 is connected to the negative electrode of the battery; the second pin of the first chip U1 is connected to the negative electrode of the battery; the third pin and the fourth pin of the first chip U1 are connected to the two ends of the sampling resistor 5, and the sixth capacitor C6 is also connected between the third pin and the fourth pin; the fifth pin of the first chip U1 is connected to the +5V voltage, and the fifth pin is also connected to one end of the tenth capacitor C10, and the other end of the tenth capacitor C10 is connected to the negative electrode of the battery.

[0043] The output current acquisition unit 34 also includes an amplifier U2D, the positive input terminal 12 of the amplifier U2D is connected to one end of the nineteenth resistor R19, and the other end of the nineteenth resistor R19 is connected to the +5V voltage; the positive input terminal 12 of the amplifier U2D is also connected to one end of the twelfth capacitor C12, and the other end of the twelfth capacitor C12 is connected to the negative electrode of the battery; the positive input terminal 12 is also connected to one end of the thirteenth resistor R13, and the other end of the thirteenth resistor R13 is connected to the negative electrode of the battery; the positive input terminal 12 is also connected to one end of the thirteenth resistor R14, and the other end of the thirteenth resistor R14 is connected to the output terminal 14 of the amplifier U2D; the negative input terminal 13 of the amplifier U2D is connected to the twentieth resistor R The output end of the amplifier U2D is connected to one end of the 18th resistor R18, and the other end of the 18th resistor R18 is connected to the +5V voltage; the output end of the amplifier U2D is connected to the cathode of the third diode D3, the cathode of the ninth diode D9, the cathode of the sixth diode D6 and the cathode of the tenth diode D10, the anode of the third diode D3 is connected to one end of the 16th resistor R16, and the other end of the 16th resistor R16 is connected to the +5V voltage; the anode of the ninth diode D9 is connected to the cathode of the battery; the anode of the third diode D3 is also connected to the MCU module.

[0044] For details, see Figure 4 As shown, it is a circuit diagram of the MCU module of an embodiment of the utility model, including a first IC chip IC1, a second pin of the first IC chip IC1 is connected to the positive electrode of the third diode D3, a third pin is connected to a +5V voltage, and the third pin is also connected to one end of a nineteenth capacitor C19, and the other end of the nineteenth capacitor C19 is grounded; the fourth pin is grounded; the tenth pin and the eleventh pin are respectively connected to the first drive unit 11 and the first drive unit 12; the twelfth pin is respectively connected to the first drive unit 11 and the first drive unit 12; the thirteenth pin is connected to one end of the twelfth resistor R12 connected to the eleventh capacitor C11; the fourteenth pin is connected to the thirty-ninth resistor R39 to receive the load output voltage; the fifteenth pin is connected to the thirty-third resistor R33 to receive the voltage of the second battery; the sixteenth pin is connected to the twenty-seventh resistor R27 to receive the voltage of the first battery.

[0045] See also Figure 5As shown, it is a circuit diagram of the first driving unit of an embodiment of the utility model, which receives the switch signal sent by the first IC chip IC1 through the third resistor R3, the twenty-third resistor R23 and the thirty-fourth resistor R34, outputs the B1_M_S signal to the source of the second MOS tube Q2 and the source of the third MOS tube Q3 through the emitter of the eleventh transistor Q11, and outputs the B1_M_G signal to the gate of the second MOS tube Q2 and the gate of the third MOS tube Q3 through the collector of the eleventh transistor Q11 and the collector of the fifteenth transistor Q15.

[0046] Specifically, one end of the third resistor R3 is connected to the twelfth pin of the first IC chip IC1, the other end of the third resistor R3 is connected to the base of the fourth transistor Q4, the emitter of the fourth transistor Q4 is connected to the negative electrode of the battery, and the collector of the fourth transistor Q4 is connected to the base of the first transistor Q1 and the base of the fifth transistor Q5 respectively; one end of the second resistor R2 is connected between the base and the collector of the first transistor Q1, the emitter of the first transistor Q1 is connected to the emitter of the fifth transistor Q5, and the collector of the fifth transistor Q5 is connected to the negative electrode of the battery; the emitter of the first transistor Q1 is connected to one end of the second capacitor C2, and the other end of the second capacitor C2 is connected to the negative electrode of the first voltage stabilizing diode ZD1. The positive electrode of the first voltage stabilizing diode ZD1 is connected to the negative electrode of the battery, the negative electrode of the first diode D1 and the negative electrode of the seventh diode D7 are connected to the positive electrode of the first battery through the third capacitor C3, and the negative electrode of the first diode D1 and the negative electrode of the seventh diode D7 are also connected to the positive electrode of the first battery through the fourth resistor R4; the base of the fourth triode Q4 is connected to the negative electrode of the battery through the sixth resistor R6, and the base of the fourth triode Q4 is also connected to the negative electrode of the battery through the fourth capacitor C4; the collector of the first triode Q1 is connected to the negative electrode of the battery through R1, and the collector of the first triode Q1 is also connected to the +12V voltage through the first resistor.

[0047] Specifically, one end of the twenty-third resistor R23 is connected to the eleventh pin of the first IC chip IC1, and the other end of the twenty-third resistor R23 is connected to the base; the base of the thirteenth transistor Q13 is connected to the negative electrode of the battery through the thirteenth capacitor C13 and the twenty-fifth resistor R25 respectively, the emitter of the thirteenth transistor Q13 is connected to the negative electrode of the battery, the collector of the thirteenth transistor Q13 is connected to one end of the twenty-first resistor R21, and the other end of the twenty-first resistor R21 is connected to the positive electrode of the fourth diode D4, the positive electrode of the fourth diode D4 is also connected to one end of the fifteenth resistor R15, and the other end of the fifteenth resistor R15 is connected to the negative electrode of the first diode D1; the negative electrode of the fourth diode D4 is connected to the base of the eleventh transistor Q11.

[0048] Specifically, one end of the thirty-fourth resistor R34 is connected to the eleventh pin of the first IC chip IC1, and the other end of the thirty-fourth resistor R34 is connected to the base of the seventeenth transistor Q17. The base of the seventeenth transistor Q17 is connected to the negative electrode of the battery through the sixteenth capacitor C16 and the thirty-sixth resistor R36 respectively, the emitter of the seventeenth transistor Q17 is connected to the negative electrode of the battery, and the collector of the seventeenth transistor Q17 is connected to the base of the fifteenth transistor Q15 through the thirty-first resistor R31; the twenty-eighth resistor R28 is connected between the base and the emitter of the fifteenth transistor Q15, and the emitter of the fifteenth transistor Q15 is also connected to the negative electrode of the first diode D1.

[0049] See also Figure 6 As shown, it is a circuit diagram of the second driving unit of an embodiment of the utility model, receiving the switch signal sent by the first IC chip IC1 through the ninth resistor R9, the twenty-fourth resistor R24 ​​and the thirty-fifth resistor R35, outputting the B2_M_S signal to the source of the sixth MOS tube Q6 and the source of the seventh MOS tube Q7 through the emitter of the twelfth transistor Q12, and outputting the B2_M_G signal to the gate of the sixth MOS tube Q6 and the gate of the seventh MOS tube Q7 through the collector of the twelfth transistor Q12 and the collector of the sixteenth transistor Q16; its specific circuit connection structure is consistent with the first driving unit.

[0050] When the present embodiment is working, the MCU outputs a PWM signal to form driving power supplies B1_M_power and B2_M_Power; during the battery operation, the MCU module continuously collects the voltage of the first battery and the voltage of the second battery through the sampling and protection module, and performs relevant control according to the above voltage information, specifically:

[0051] If the voltage of the first battery is greater than the threshold voltage, Ctrl_B1_dr outputs a high level signal to drive the first fault isolation unit to work; at the same time, Ctrl_B2_dr outputs a low level to turn off the second fault isolation unit;

[0052] If the voltage of the first battery is lower than the threshold voltage and the voltage of the second battery is greater than the threshold voltage, Ctrl_B1_dr outputs a low level signal to turn off the first fault isolation unit; at the same time, Ctrl_B2_dr outputs a high level to turn on the second fault isolation unit;

[0053] If the voltage of the first battery and the voltage of the second battery are both lower than the threshold voltage, Ctrl_B1_dr and Ctrl_B2_dr output a low level, turning off the first fault isolation unit and the second fault isolation unit;

[0054] When this embodiment is working, the MCU also collects the output load current, that is, the load current, through the sampling and protection module. If the load current is higher than the threshold current, Ctrl_B1_dr and Ctrl_B2_dr output a low level to turn off the first fault isolation unit and the second fault isolation unit.

[0055] When this embodiment is working, the MCU also collects the load output voltage through the sampling and protection module to detect the MOS state. For example, after the first fault isolation unit or the second fault isolation unit is turned on, the load voltage Load_OUT is collected below the threshold voltage, and it is judged that the MOS circuit is abnormal; when the first fault isolation unit and the second fault isolation unit are both turned off, the load voltage Load_OUT is collected above the threshold voltage, and it is judged that the MOS circuit is abnormal.

[0056] It can be seen that the utility model can control the load output circuit through MOS to achieve microsecond-level fast opening and closing. During the battery power switching process, the load does not lose power. When the load output is short-circuited or overloaded, it can be quickly protected by the fault isolation unit without replacing the fuse, reducing maintenance time and maintenance costs.

[0057] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A dual battery system load control circuit, characterized in that: include: A first battery module includes a first drive unit, a first battery fault isolation unit and a first battery connected in sequence; A second battery module includes a second drive unit, a second battery fault isolation unit and a second battery connected in sequence; A sampling resistor, one end of which is connected to the first battery fault isolation unit and the second battery fault isolation unit respectively, and the other end of which is connected to the load; The sampling and protection module includes a first voltage acquisition unit, a second voltage acquisition unit, an output voltage acquisition unit and an output current acquisition unit, wherein the first voltage acquisition unit is connected to the first battery, the second voltage acquisition unit is connected to the second battery, the output voltage acquisition unit is connected to one end of the sampling resistor connected to the load, and the output current acquisition unit is connected to both ends of the sampling resistor; The MCU module has an input end connected to the first voltage acquisition unit, the second voltage acquisition unit, the output voltage acquisition unit and the output current acquisition unit respectively, and an output end connected to the first drive unit and the second drive unit respectively.

2. The dual battery system load control circuit according to claim 1, characterized in that: The first battery and the second battery share a negative electrode.

3. The dual battery system load control circuit according to claim 1, characterized in that: The first battery fault isolation unit includes a first MOS tube and a second MOS tube, the source of the first MOS tube is connected to the source of the second MOS tube, the gate of the first MOS tube is connected to the gate of the second MOS tube, the drain of the first MOS tube is connected to the positive electrode of the first battery, and the drain of the second MOS tube is connected to the sampling resistor; The second battery fault isolation unit includes a third MOS tube and a fourth MOS tube, the source of the third MOS tube is connected to the source of the fourth MOS tube, the gate of the third MOS tube is connected to the gate of the fourth MOS tube, the drain of the third MOS tube is connected to the positive electrode of the second battery, and the drain of the fourth MOS tube is connected to the sampling resistor.

4. The dual battery system load control circuit according to claim 1, characterized in that: The MCU module includes a first IC chip, an input end of the first IC chip is respectively connected to the first voltage acquisition unit, the second voltage acquisition unit, the output voltage acquisition unit and the output current acquisition unit of the sampling and protection module, and an output end of the first IC chip is respectively connected to the first drive unit and the second drive unit.

5. The dual battery system load control circuit according to claim 2, characterized in that: The first voltage acquisition unit includes a twenty-seventh resistor, a thirtieth resistor and a fifteenth capacitor, one end of the twenty-seventh resistor is connected to the positive electrode of the first battery, the other end of the twenty-seventh resistor is respectively connected to the MCU module, one end of the fifteenth capacitor, and one end of the thirtieth resistor, the other end of the fifteenth capacitor is connected to the negative electrode of the battery, and the other end of the thirtieth resistor is connected to the negative electrode of the battery.

6. The dual battery system load control circuit according to claim 2, characterized in that: The second voltage acquisition unit includes a thirty-third resistor, a thirty-seventh resistor and a seventeenth capacitor, one end of the thirty-third resistor is connected to the positive electrode of the second battery, the other end of the thirty-third resistor is connected to the MCU module, one end of the seventeenth capacitor and one end of the thirty-seventh resistor respectively, the other end of the seventeenth capacitor is connected to the negative electrode of the battery, and the other end of the thirty-seventh resistor is connected to the negative electrode of the battery.

7. The dual battery system load control circuit according to claim 2, characterized in that: The output voltage acquisition unit includes a thirty-ninth resistor, a fortieth resistor and a twentieth capacitor, one end of the thirty-ninth resistor is connected to one end of the sampling resistor connected to the load, and the other end of the thirty-ninth resistor is respectively connected to the MCU module, one end of the twentieth capacitor and one end of the fortieth resistor; the other end of the twentieth capacitor is connected to the negative electrode of the battery, and the other end of the fortieth resistor is connected to the negative electrode of the battery.

8. The dual battery system load control circuit according to claim 1, characterized in that: The output current acquisition unit comprises a first chip, an input end of the first chip is connected to two ends of a sampling resistor, and an output end of the first chip is connected to an MCU module.

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