A series bypass bidirectional execution circuit and bypass switching method

Abstract

The present invention relates to the field of battery fault switching, and in particular to a series bypass bidirectional execution circuit capable of constant voltage mode and a bypass switching method. A series bypass bidirectional execution circuit comprises: a plurality of batteries connected in series; each battery is connected in series with two main circuit MOS tubes to form a battery main circuit; the battery main circuit is connected in parallel with a bypass circuit; the bypass circuit comprises: two bypass MOS tubes connected in series; a series bypass bidirectional execution circuit is provided with a bypass switching MCU processor for regulating the battery main circuit and the corresponding bypass circuit; the bypass switching MCU processor outputs two control signals, one for controlling the two main circuit MOS tubes of the battery main circuit, and the other for controlling the two bypass MOS tubes. The beneficial effects of the present invention are: reducing costs, eliminating current jitter during battery bypass, and increasing system reliability.

Description

Technical Field

[0001] The invention relates to the field of battery fault switching, and in particular to a series bypass bidirectional execution circuit capable of constant voltage mode and a bypass switching method. Background Art

[0002] When a battery fails, a MOS tube switching circuit can be used to bypass the faulty battery. However, the traditional switching method has jitter during the switching process. In addition, the circuit constant voltage accuracy is low, and the battery cannot be bypassed in the constant voltage mode. Only the constant current mode can be executed.

[0003] The main defects are that the voltage is high and the constant voltage accuracy is low; the switching process causes current jitter, which makes the MOS tube prone to failure; and the use of high common-mode instrument amplifier sampling is costly. Summary of the invention

[0004] The object of the present invention is to provide a series bypass bidirectional execution circuit and a bypass switching method to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A series bypass bidirectional execution circuit includes: a plurality of batteries connected in series; each battery is connected in series with two main circuit MOS tubes to form a battery main circuit; a bypass circuit is connected in parallel with the battery main circuit; the bypass circuit includes: two bypass MOS tubes connected in series; a series bypass bidirectional execution circuit is provided with a bypass switching MCU processor for regulating the battery main circuit and the corresponding bypass circuit;

[0007] The bypass switching MCU processor outputs two control signals, one to control the two main circuit MOS tubes of the battery main circuit, and the other to control the two bypass MOS tubes;

[0008] When the battery voltage is abnormal, the bypass switching MCU processor adjusts the two control signal voltages to make the two main circuit MOS tubes equivalent to variable resistors, and the two bypass MOS tubes are in a linear state equivalent to variable resistors, and gradually shares the battery main circuit current through the two bypass MOS tubes until the two main circuit MOS tubes are turned off to cut off the battery main circuit, so that the current completely passes through the bypass circuit, completing the bypass switching of the faulty battery main circuit.

[0009] As a further solution of the present invention: a serial bypass bidirectional execution circuit also includes: an ADC sampling module for detecting the battery voltage and a voltage detection MCU processor for determining whether the battery voltage is abnormal.

[0010] As a further solution of the present invention: the sampling of different batteries is switched by photoelectric thyristor control.

[0011] As a further solution of the present invention: a serial bypass bidirectional execution circuit is provided with a DAC circuit;

[0012] The DAC circuit forms an adder with the operational amplifier U12A through the two output ports of the DAC chip to increase the DAC resolution; and uses the operational amplifier U12B to increase the reference voltage.

[0013] As a further solution of the present invention: the two main circuit MOS tubes are MOS tube Q1 and MOS tube Q2; the two bypass MOS tubes are MOS tube Q3 and MOS tube Q4; the bypass switching MCU processor is MCU2;

[0014] The bypass switching MCU processor outputs two control signals, DAC1 and DAC2;

[0015] A series bypass bidirectional execution circuit also includes: operational amplifiers U2A, U2B, U1B, resistors R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, and capacitor C1;

[0016] The output DAC1 of MCU2 is connected to the positive input of the op amp U2B through the resistor R9; the positive input of the op amp U2B is grounded through the resistor R10; the negative input of the op amp U2B is connected to the output of the op amp U2B through the capacitor C1;

[0017] The output of the operational amplifier U2B is connected to the G poles of the MOS tubes Q1 and Q2 through the resistor R15; the G poles of the MOS tubes Q1 and Q2 are connected to one end of the resistor R16; the S poles of the MOS tubes Q1 and Q2 are connected to the other end of the resistor R16; the D pole of the MOS tube Q2 is connected to the positive pole of the battery;

[0018] The D pole of the MOS tube Q1 is connected to the D pole of the MOS tube Q3; the G poles of the MOS tube Q3 and the MOS tube Q4 are connected to one end of the resistor R18; the S poles of the MOS tube Q3 and the MOS tube Q4 are connected to the other end of the resistor R18; the D pole of the MOS tube Q4 is connected to the negative pole of the battery;

[0019] The output DAC2 of MCU2 is connected to the positive input of the operational amplifier U1B through the resistor R12; the positive input of the operational amplifier U1B is grounded through the resistor R13; the negative input of the operational amplifier U1B is connected to the output of the operational amplifier U1B through the resistor R14; the output of the operational amplifier U1B is connected to the G poles of the MOS tubes Q3 and Q4 through the resistor R17; the output of the operational amplifier U2B is connected to the negative input of the operational amplifier U1B through the resistor R11;

[0020] The output of op amp U2A is connected to the negative input of op amp U2B through resistor R8; the negative input of op amp U2A is connected to the output of op amp U2A through resistor R7; the negative input of op amp U2A is connected to the negative pole of the battery through resistor R6; the positive input of op amp U2A is grounded through resistor R4; the positive input of op amp U2A is connected to the D pole of MOS tube Q1 through resistor R5.

[0021] The bypass switching method of the series bypass bidirectional execution circuit comprises the following steps:

[0022] Scan the voltage of each battery to determine whether the voltage is abnormal. If not, no switching is required. If so, for batteries with abnormal voltage, the MCU processor controls the two main circuit MOS tubes to be equivalent to variable resistors through its bypass switching, and the two bypass MOS tubes are in a linear state equivalent to variable resistors. The battery main circuit current is gradually shared through the two bypass MOS tubes until the two main circuit MOS tubes are turned off to cut off the battery main circuit, so that the current completely passes through the bypass circuit, completing the bypass switching of the faulty battery main circuit.

[0023] The invention is beneficial in that it reduces costs, eliminates current jitter during battery bypass, and increases system reliability.

[0024] The dedicated control circuit composed of MCU, current transformer and operational amplifier controls the MOS tube, making the MOS tube work in two states: linear and switch. The voltage changes slowly during the battery bypass process, the voltage of the high-power DC / DC main circuit follows the regulation, and there is no impact on the bypass overshoot. The single-cell battery scanning circuit abandons the high-cost high common-mode instrument and amplifier, adopts photoelectric thyristor switching, and adopts the corresponding conversion circuit with a sampling accuracy of one ten-thousandth.

[0025] Other features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a circuit diagram of a series bypass bidirectional execution circuit of the present invention;

[0027] Figure 2 yes Figure 1 A circuit diagram of a bypass module of a serial bypass bidirectional execution circuit;

[0028] Figure 3 yes Figure 1 A circuit diagram of a collection module of a serial bypass bidirectional execution circuit;

[0029] Figure 4 yes Figure 1 A circuit diagram of a DAC circuit of a serial bypass bidirectional execution circuit;

[0030] Figure 5 yes Figure 1 A circuit block diagram of a bypass module of a serial bypass bidirectional execution circuit in a normal working state;

[0031] Figure 6 yes Figure 5 Circuit block diagram of the bypass module during the switching process;

[0032] Figure 7 yes Figure 5 Circuit block diagram of the bypass module after switching is completed. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] like Figures 1 to 7 As shown, a series bypass bidirectional execution circuit includes: a plurality of batteries connected in series. Each battery is connected in series with two main circuit MOS tubes to form a battery main circuit. The battery main circuit is connected in parallel with a bypass circuit. The bypass circuit includes: two bypass MOS tubes connected in series. A series bypass bidirectional execution circuit is provided with a bypass switching MCU processor for regulating the battery main circuit and the corresponding bypass circuit.

[0035] The bypass switching MCU processor outputs two control signals, one to control the two main circuit MOS tubes of the battery main circuit, and the other to control the two bypass MOS tubes.

[0036] When the battery voltage is abnormal, the bypass switching MCU processor adjusts the two control signal voltages to make the two main circuit MOS tubes equivalent to variable resistors, and the two bypass MOS tubes are in a linear state equivalent to variable resistors, and gradually shares the battery main circuit current through the two bypass MOS tubes until the two main circuit MOS tubes are turned off to cut off the battery main circuit, so that the current completely passes through the bypass circuit, completing the bypass switching of the faulty battery main circuit.

[0037] As a specific implementation, the two main circuit MOS transistors are MOS transistor Q1 and MOS transistor Q2. The two bypass MOS transistors are MOS transistor Q3 and MOS transistor Q4. The bypass switching MCU processor is MCU2.

[0038] The bypass switching MCU processor outputs two control signals, namely DAC1 and DAC2.

[0039] A series bypass bidirectional execution circuit also includes: operational amplifiers U2A, U2B, U1B, resistors R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, and capacitor C1.

[0040] The output DAC1 of MCU2 is connected to the positive input of the op amp U2B through the resistor R9. The positive input of the op amp U2B is grounded through the resistor R10. The negative input of the op amp U2B is connected to the output of the op amp U2B through the capacitor C1.

[0041] The output of the op amp U2B is connected to the G poles of the MOS tubes Q1 and Q2 through the resistor R15. The G poles of the MOS tubes Q1 and Q2 are connected to one end of the resistor R16. The S poles of the MOS tubes Q1 and Q2 are connected to the other end of the resistor R16. The D pole of the MOS tube Q2 is connected to the positive pole of the battery.

[0042] The D pole of MOS tube Q1 is connected to the D pole of MOS tube Q3. The G poles of MOS tube Q3 and MOS tube Q4 are connected to one end of resistor R18. The S poles of MOS tube Q3 and MOS tube Q4 are connected to the other end of resistor R18. The D pole of MOS tube Q4 is connected to the negative pole of the battery.

[0043] The output DAC2 of MCU2 is connected to the positive input of the op amp U1B through the resistor R12. The positive input of the op amp U1B is grounded through the resistor R13. The negative input of the op amp U1B is connected to the output of the op amp U1B through the resistor R14. The output of the op amp U1B is connected to the G poles of the MOS tubes Q3 and Q4 through the resistor R17. The output of the op amp U2B is connected to the negative input of the op amp U1B through the resistor R11.

[0044] The output of the op amp U2A is connected to the negative input of the op amp U2B through resistor R8. The negative input of the op amp U2A is connected to the output of the op amp U2A through resistor R7. The negative input of the op amp U2A is connected to the negative pole of the battery through resistor R6. The positive input of the op amp U2A is grounded through resistor R4. The positive input of the op amp U2A is connected to the D pole of the MOS tube Q1 through resistor R5.

[0045] refer to Figure 2 and Figure 3, using battery BT5 as an example, the bypass module receives information through isolated RS485, DAC1 of MCU2 sends 2.5V, turns on MOS tubes Q1 and Q2, at which time MOS tubes Q1 and Q2 are in the on state, DAC2 sends 0V, turns off MOS tubes Q3 and Q4. MCU1 turns on U4 and U5 to measure the voltage of battery 1, turns on U6 and U7 to measure the voltage of battery 2, turns on U8 and U9 to measure the power supply of battery 3, turns on U10 and U11 to measure the power supply of battery 4, and so on. Only four groups of batteries are drawn above, and the number of batteries is not limited to 4 groups. When the voltage detection of battery BT5 is abnormal, MCU2 adjusts the DAC1 voltage and DAC2 voltage to make MOS tubes Q1 and Q2 equivalent to variable resistor R2, and MOS tubes Q3 and Q4 are in a linear state, and MOS tubes Q3 and Q4 are equivalent to variable resistor R1. Let MOS tubes Q3 and Q4 gradually share the main loop current, and keep the voltage of MOS tube Q3 + MOS tube Q4 consistent with the voltage of battery BT5. The total switching time is about 10mS, until MCU2 adjusts DAC1, the output voltage is 0, turn off MOS tubes Q1 and Q2, and let all current flow through MOS tubes Q3 and Q4. Adjust the DAC3 and DAC4 pins of the DAC chip, gradually reduce the set voltage, and increase the voltage of the DAC2 pin of MCU2 to make it in the on state. At this time, the abnormal battery cell is kicked out successfully.

[0046] refer to Figures 5 to 7 , simulating the process of bypassing the battery BT_1. When the voltage of the battery BT_1 is abnormal, the main circuit MOS tube Q1 and MOS tube Q2 are equivalent to variable resistors, and the two bypass MOS tubes Q3 and MOS tube Q4 are equivalent to variable resistors in a linear state. The battery main circuit current is gradually shared by the two bypass MOS tubes Q3 and MOS tube Q4 until the two main circuit MOS tubes Q1 and MOS tube Q2 are turned off to cut off the battery BT_1 main circuit, so that the current completely passes through the bypass circuit, completing the bypass switching of the faulty battery BT_1 main circuit. Among them, the "?" in MOS tube Q? and battery BT_N? refers to numbers, which are used to represent different MOS tubes and different batteries. MOS tube Q? and battery BT_N? constitute a battery main circuit and its parallel bypass circuit. You can refer to the battery BT_1 main circuit and its parallel bypass circuit above, which have the same structure.

[0047] As a further solution of the present invention: a serial bypass bidirectional execution circuit also includes: an ADC sampling module for detecting the battery voltage and a voltage detection MCU processor for determining whether the battery voltage is abnormal.

[0048] As a further solution of the present invention: the sampling of different batteries is switched by photoelectric thyristor control.

[0049] As a further solution of the present invention: a serial bypass bidirectional execution circuit is provided with a DAC circuit.

[0050] The DAC circuit uses the two output ports of the DAC chip and the op amp U12A to form an adder to increase the DAC resolution. The op amp U12B is used to increase the reference voltage and improve the constant voltage accuracy of the device.

[0051] The bypass switching method of the series bypass bidirectional execution circuit comprises the following steps:

[0052] Scan the voltage of each battery to determine whether the voltage is abnormal. If not, no switching is required. If so, for batteries with abnormal voltage, the MCU processor controls the two main circuit MOS tubes to be equivalent to variable resistors through its bypass switching, and the two bypass MOS tubes are in a linear state equivalent to variable resistors. The battery main circuit current is gradually shared through the two bypass MOS tubes until the two main circuit MOS tubes are turned off to cut off the battery main circuit, so that the current completely passes through the bypass circuit, completing the bypass switching of the faulty battery main circuit.

[0053] Specifically, the user manually or automatically sends the detection process through the host computer. Open the main path of the bypass module. Start the main power DC / DC module, and then scan the voltage of each battery in turn. When the voltage of the battery is abnormal, start the above switching method to perform bypass switching and remove the abnormal battery.

[0054] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0055] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A series bypass bidirectional execution circuit, characterized in that: include: A plurality of batteries connected in series; each battery is connected in series with two main circuit MOS tubes to form a main circuit of the battery; The battery main circuit is connected in parallel with a bypass circuit; The bypass circuit includes: two bypass MOS tubes connected in series; the series bypass bidirectional execution circuit is provided with a bypass switching MCU processor for regulating the battery main circuit and the corresponding bypass circuit; The bypass switching MCU processor outputs two control signals, one of which controls the two main circuit MOS tubes of the battery main circuit, and the other controls the two bypass MOS tubes; When the battery voltage is abnormal, the bypass switching MCU processor adjusts the voltage of the two control signals to make the two main circuit MOS tubes equivalent to variable resistors, and the two bypass MOS tubes are in a linear state equivalent to variable resistors, and gradually shares the battery main circuit current through the two bypass MOS tubes until the two main circuit MOS tubes are turned off to cut off the battery main circuit, so that the current completely passes through the bypass circuit, completing the bypass switching of the faulty battery main circuit; The two main circuit MOS tubes are MOS tube Q1 and MOS tube Q2; the two bypass MOS tubes are MOS tube Q3 and MOS tube Q4; the bypass switching MCU processor is MCU2; The bypass switching MCU processor outputs two control signals, DAC1 and DAC2; The series bypass bidirectional execution circuit also includes: operational amplifiers U2A, U2B, U1B, resistors R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, and capacitor C1; The output DAC1 of the MCU2 is connected to the positive phase input of the operational amplifier U2B through the resistor R9; the positive phase input of the operational amplifier U2B is grounded through the resistor R10; the negative phase input of the operational amplifier U2B is connected to the output of the operational amplifier U2B through the capacitor C1; The output of the operational amplifier U2B is connected to the G poles of the MOS transistor Q1 and the MOS transistor Q2 through the resistor R15; the G poles of the MOS transistor Q1 and the MOS transistor Q2 are connected to one end of the resistor R16; the S poles of the MOS transistor Q1 and the MOS transistor Q2 are connected to the other end of the resistor R16; the D pole of the MOS transistor Q2 is connected to the positive pole of the battery; The D pole of the MOS tube Q1 is connected to the D pole of the MOS tube Q3; the G poles of the MOS tube Q3 and the MOS tube Q4 are connected to one end of the resistor R18; the S poles of the MOS tube Q3 and the MOS tube Q4 are connected to the other end of the resistor R18; the D pole of the MOS tube Q4 is connected to the negative pole of the battery; The output DAC2 of the MCU2 is connected to the positive phase input of the operational amplifier U1B through the resistor R12; the positive phase input of the operational amplifier U1B is grounded through the resistor R13; the negative phase input of the operational amplifier U1B is connected to the output of the operational amplifier U1B through the resistor R14; the output of the operational amplifier U1B is connected to the G poles of the MOS tube Q3 and the MOS tube Q4 through the resistor R17; the output of the operational amplifier U2B is connected to the negative phase input of the operational amplifier U1B through the resistor R11; The output of the op amp U2A is connected to the negative input of the op amp U2B through the resistor R8; the negative input of the op amp U2A is connected to the output of the op amp U2A through the resistor R7; the negative input of the op amp U2A is connected to the negative electrode of the battery through the resistor R6; the positive input of the op amp U2A is grounded through the resistor R4; the positive input of the op amp U2A is connected to the D electrode of the MOS tube Q1 through the resistor R5.

2. A series bypass bidirectional execution circuit according to claim 1, characterized in that: The serial bypass bidirectional execution circuit further includes: an ADC sampling module for detecting the battery voltage and a voltage detection MCU processor for determining whether the battery voltage is abnormal.

3. A series bypass bidirectional execution circuit according to claim 2, characterized in that: The sampling of different batteries is switched by photoelectric thyristor control.

4. The series bypass bidirectional execution circuit according to claim 1, characterized in that: The series bypass bidirectional execution circuit is provided with a DAC circuit; The DAC circuit forms an adder with the operational amplifier U12A through two output ports of the DAC chip to increase the DAC resolution; and utilizes the operational amplifier U12B to increase the reference voltage.

5. A bypass switching method for a series bypass bidirectional execution circuit according to any one of claims 1 to 4, characterized in that: The following steps are involved: Scan the voltage of each battery to determine whether the voltage is abnormal. If not, no switching is required. If yes, for the battery with abnormal voltage, control the two main circuit MOS tubes as equivalent variable resistors through the bypass switching MCU processor, and the two bypass MOS tubes as equivalent variable resistors in a linear state, and gradually share the battery main circuit current through the two bypass MOS tubes until the two main circuit MOS tubes are turned off to cut off the battery main circuit, so that the current completely passes through the bypass circuit, and the bypass switching of the faulty battery main circuit is completed.

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