Novel PDU control positive terminal MOS drive circuit

Abstract

The utility model discloses a novel PDU control positive end MOS drive circuit, which comprises a DC-DC isolation power supply module and a BMS master control, the input end of the DC-DC isolation power supply module is respectively connected with the total positive end and the total negative end of a battery, the battery supplies power to the DC-DC isolation power supply module, and the output end of the DC-DC isolation power supply module outputs a power supply BMS12V + and a power supply BGND to be connected with the BMS master control so as to provide a power supply for the BMS master control; the positive input end of the DC-DC isolation power supply module is connected with the MOS tube M1, one path of isolation DC module is adopted as a driving power supply for the MOS tube M1, and the input end of the isolation DC module is connected to BMS12V + through a diode D11 and is connected to a charging end CHGA + of a BMS master controller through a diode D12; the negative input end of the DC-DC isolation power supply module is connected with the MOS tube M2, and a linear voltage stabilizing circuit and a second driving circuit are arranged to provide a driving source for the MOS tube M2.

Description

Technical Field

[0001] This utility model belongs to the field of lithium battery applications, specifically relating to a novel PDU-controlled positive terminal MOS driving circuit. Background Technology

[0002] For early PDUs, such as Figure 1 As shown, due to the limited operating voltage range of the DC-DC isolated power supply module, when the battery voltage drops below the minimum startup voltage, both the positive-terminal power MOSFET (M1) and the negative-terminal power MOSFET (M2) will lose their driving power. The DC-DC isolated power supply module is a multi-output power supply module. VS1+ and VS1- drive M1, VS2+ and VS2- drive M2, BMS12V+ and BGND are the BMS main control power supply, and CHG_A+ and BGND are the charger auxiliary 12V power supply. The drive circuit uses high-speed optocouplers. When the battery voltage is lower than the power module's startup voltage, the power module cannot start and cannot heat or charge the battery. Furthermore, early power modules with multiple outputs were prone to voltage instability due to the difficulty in transformer production and manufacturing; for example, a change in the current of one output could cause changes in the voltages of other outputs. Utility Model Content

[0003] To overcome the shortcomings of the existing technology, the purpose of this utility model is to provide a novel PDU-controlled positive terminal MOS driving circuit, which drives the MOS transistor to heat the battery when the power module fails to work, so as to solve the problem of the battery being unable to heat up and charge under low temperature conditions.

[0004] The technical problem solved by this utility model can be achieved through the following technical solution:

[0005] The novel PDU-controlled positive terminal MOS drive circuit includes a DC-DC isolated power supply module and a BMS main controller. The input terminals of the DC-DC isolated power supply module are connected to the positive and negative terminals of the battery, respectively, and the battery supplies power to the DC-DC isolated power supply module. The output terminals of the DC-DC isolated power supply module output power BMS12V+ and BGND, which are connected to the BMS main controller to provide power to the BMS main controller. The positive input terminal of the DC-DC isolated power supply module is connected to MOS transistor M1, and an isolated DC module is used as the driving power supply for MOS transistor M1. The input terminal of the isolated DC module is connected to BMS12V+ through diode D11 and to the charging terminal CHGA+ of the BMS main controller through diode D12. The negative input terminal of the DC-DC isolated power supply module is connected to MOS transistor M2, and a linear voltage regulator circuit and a second drive circuit are set up to provide a driving source for MOS transistor M2.

[0006] Furthermore, the positive input terminal of the DC-DC isolated power supply module is connected to switch SW1 as an external switch to control the DC-DC isolated power supply module to enable; switch SW2 is set between the positive input terminal of the DC-DC isolated power supply module and the BMS main controller, and the BMS main controller is controlled by switch SW2 to realize the self-locking function after power-on.

[0007] Furthermore, the charging terminals CHGA+ and BGND of the BMS main controller are connected to the charger to provide an auxiliary 12V power supply.

[0008] Furthermore, the isolated DC module is connected to the MOSFET M1 through a first driving circuit to control the switching of the MOSFET M1; one end of the first driving circuit is connected to the isolated DC module and the other end is connected to the BMS main controller.

[0009] Furthermore, the first driving circuit includes an optocoupler relay PC1 and a first fast discharge circuit. The optocoupler relay PC1 uses a common optocoupler for driving isolation. The first fast discharge circuit includes a transistor Q5, a resistor R17, and a diode D10. The base of the transistor Q5 is connected to the resistor R17, the collector is connected to the source of the MOSFET M1, and the emitter is connected to the diode D10. The other end of the resistor R17 is also connected to the source of the MOSFET M1.

[0010] Furthermore, a capacitor C2 is connected between the positive and negative output terminals of the isolated DC module. Capacitor C2 serves as a filter capacitor for the drive power supply. The positive output terminal of the isolated DC module is connected to the emitter of transistor Q3 via diode D3. A resistor R4 is placed between the emitter and base of transistor Q3. The base is connected to the output terminal of optocoupler relay PC1 via resistor R6. The collector is connected to resistor R8 and diode D5 in sequence, and then to diode D10 and resistor R17. The input terminal of optocoupler relay PC1 is connected to the heating positive control terminal of the BMS main control via resistor R10, capacitor C5, resistor R16, and diode D8. Transistor Q3, resistor R4, resistor R6, and optocoupler relay PC1 form a positive MOS drive power supply switching circuit, which controls the opening and closing of the drive voltage between the gate and source of MOS transistor M1.

[0011] Furthermore, one end of the linear regulator circuit is connected to the DC-DC isolated power supply module and the other end is connected to the MOSFET M2; one end of the second drive circuit is connected to the BMS main controller and the other end is connected to the MOSFET M2; and the linear regulator circuit and the second drive circuit are simultaneously connected to VLM+ (i.e., the output voltage network of the regulator circuit, with a voltage of around 13V).

[0012] Furthermore, the linear voltage regulator circuit includes a reverse-connection protection diode D1, a transistor Q1, and a transistor Q2. One end of diode D1 is connected to the DC-DC isolated power supply module, and the other end is simultaneously connected to resistors R1, R2, and R3. The other end of resistor R1 is connected to capacitor C1 and the base of transistor Q1. The other end of resistor R2 is connected to the collector of transistor Q2, and the other end of resistor R3 is connected to the collector of transistor Q1. The other end of capacitor C1 is connected to diode D2 and capacitor C3. The other end of diode D2 is connected to the base of transistor Q1, and the other end of capacitor C3 is connected to VLM+. The base of transistor Q2 is connected to the emitter of transistor Q1, and the emitter of transistor Q2 is connected to VLM+.

[0013] Furthermore, the second driving circuit includes an optocoupler relay PC2 and a second fast discharge circuit. The optocoupler relay PC2 uses a common optocoupler for driving isolation. The output terminal of the optocoupler relay PC2 is connected to VLM+ through a resistor R5. The input terminal of the optocoupler relay PC2 is connected to a capacitor C4, a resistor R15, a resistor R14, and a diode D9, and then connected to the heating negative control terminal of the BMS main control. The second fast discharge circuit includes a transistor Q4, a resistor R7, and a diode D4. The base of the transistor Q4 is connected to a resistor R7, the collector is connected to the source of the MOSFET M2, and the emitter is connected to the diode D4. The other end of the resistor R7 is also connected to the source of the MOSFET M2. The other end of the diode D4 is connected to the output terminal of the optocoupler relay PC2. The emitter of the transistor Q4 is connected in parallel with a diode D6, a resistor R11, and a resistor R13. The other ends of the diode D6 and the resistor R11 are both connected to the source of the MOSFET M2, and the other end of the resistor R13 is connected to the gate of the MOSFET M2.

[0014] Compared with the prior art, the present invention has the following advantages:

[0015] (1) This utility model adjusts the MOS driving circuit, eliminating the need for high-speed optocouplers for driving and reducing the cost of the driving circuit; the auxiliary power supply of the charger supplies power to the isolated DC module through diode D12, enabling the battery to be heated and recharged after voltage undervoltage and power loss.

[0016] (2) The positive terminal drive of the MOS drive circuit of this utility model is powered by an isolated DC module, which can be expanded to multiple output control; the low-end cover MOS drive is driven by a discrete linear voltage regulator circuit, which can support the start of MOS control function at extremely low battery voltage (as low as 10V); the optocoupler relays PC1 and PC2 use ordinary optocouplers as drive isolation and have a fast turn-off discharge circuit. Attached Figure Description

[0017] Figure 1 This is a circuit structure diagram of an early PDU in the background art of this utility model;

[0018] Figure 2 This is a circuit structure diagram of the MOS driving circuit of this utility model. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] like Figure 2 As shown, a novel PDU-controlled positive terminal MOS drive circuit includes a DC-DC isolated power supply module and a BMS main controller. The input terminals of the DC-DC isolated power supply module are connected to the positive and negative terminals of the battery, respectively, and the battery supplies power to the DC-DC isolated power supply module. The output terminals of the DC-DC isolated power supply module output power BMS12V+ and BGND, which are connected to the BMS main controller to provide power to the BMS main controller. The positive input terminal of the DC-DC isolated power supply module is connected to MOS transistor M1, and an isolated DC module is used as the drive power supply for MOS transistor M1. The input terminal of the isolated DC module is connected to BMS12V+ through diode D11 and to the charging terminal CHGA+ of the BMS main controller through diode D12. The negative input terminal of the DC-DC isolated power supply module is connected to MOS transistor M2, and a linear voltage regulator circuit and a second drive circuit are set up to provide a drive source for MOS transistor M2. The positive input terminal of the DC-DC isolated power supply module is connected to switch SW1, which acts as an external switch to enable the DC-DC isolated power supply module. Switch SW2 is set between the positive input terminal of the DC-DC isolated power supply module and the BMS main controller. Switch SW2 controls the BMS main controller to achieve a self-locking function after power-on. The charging terminals CHGA+ and BGND of the BMS main controller are connected to the charger to provide auxiliary 12V power.

[0021] It is understandable that when the battery voltage is above 32V and the DC-DC isolated power supply module is working normally, the DC-DC isolated power supply module outputs 12V (BMS12V+, BNGD) to power the BMS main controller. At the same time, BMS12V+ powers the isolated DC module through diode D11, which in turn powers the positive terminal MOS drive circuit. When the battery voltage is below 32V and cannot work normally, the battery is charged by the charger. The charger's auxiliary 12V power supply powers the isolated DC module through diode D12, which in turn continuously powers the positive terminal MOS drive circuit.

[0022] Continue reading Figure 2 It can be seen that the isolated DC module is connected to the MOSFET M1 through the first driving circuit to control the switching of the MOSFET M1; one end of the first driving circuit is connected to the isolated DC module and the other end is connected to the BMS main controller.

[0023] The first driving circuit includes an optocoupler relay PC1 and a first fast discharge circuit. The optocoupler relay PC1 uses a common optocoupler for driving isolation. The first fast discharge circuit includes a transistor Q5, a resistor R17, and a diode D10. The base of transistor Q5 is connected to resistor R17, the collector is connected to the source of MOSFET M1, and the emitter is connected to diode D10. The other end of resistor R17 is also connected to the source of MOSFET M1. A capacitor C2 is connected between the positive and negative output terminals of the isolated DC module. Capacitor C2 is a driving power supply filter capacitor. The positive output terminal of the isolated DC module is connected to the emitter of transistor Q3 through diode D3. A resistor R4 is set between the emitter and base of transistor Q3. The base is connected to the output terminal of optocoupler relay PC1 through resistor R6. The collector is connected to resistor R8 and diode D5 in sequence, and then connected to diode D10 and resistor R17. The input terminal of optocoupler relay PC1 is connected to resistor R10, capacitor C5, resistor R16, and diode D8, and then connected to the heating positive control terminal of the BMS main control.

[0024] It can be understood that in the positive terminal of the MOS drive circuit: capacitor C2 is the drive power supply filter capacitor, connected to the positive and negative terminals of the output of the isolation DC module. The positive terminal of the isolation DC module is connected to the source of transistor Q3 by diode D3. Transistor Q3, resistors R4 and R6, and optocoupler relay PC1 form the positive MOS drive power supply switching circuit, controlling the opening and closing of the drive voltage between the gate and source (GS) of MOS transistor M1. On the control side (output side) of optocoupler relay PC1, the negative terminal of the LED is connected to the negative BGND of the BMS main control power supply. Resistor R10 is the optocoupler turn-off discharge resistor. Resistor R16 and diode D8 are connected to the positive terminal of the LED of optocoupler relay PC1, controlled by the BMS main control signal.

[0025] In this application, one end of the linear regulator circuit is connected to the DC-DC isolated power supply module and the other end is connected to the MOSFET M2; one end of the second drive circuit is connected to the BMS main controller and the other end is connected to the MOSFET M2; and the linear regulator circuit and the second drive circuit are both connected to VLM+ (which is the output voltage network of the regulator circuit). The linear voltage regulator circuit includes a reverse-connection protection diode D1, transistors Q1 and Q2. One end of diode D1 is connected to the DC-DC isolation power supply module, and the other end is connected to resistors R1, R2, and R3. The other end of resistor R1 is connected to capacitor C1 and the base of transistor Q1. The other end of resistor R2 is connected to the collector of transistor Q2. The other end of resistor R3 is connected to the collector of transistor Q1 (i.e., capacitor C1 is the base filter capacitor for transistor Q1). The other end of capacitor C1 is connected to diode D2 and capacitor C3. The other end of diode D2 is connected to the base of transistor Q1, and the other end of capacitor C3 is connected to VLM+. The base of transistor Q2 is connected to the emitter of transistor Q1, and the emitter of transistor Q2 is connected to VLM+. Resistor R1 and diode D2 constitute the voltage reference source, and transistors Q1 and Q2 amplify the output current. Capacitor C3 is the output filter capacitor.

[0026] The second driving circuit includes an optocoupler relay PC2 and a second fast discharge circuit. The optocoupler relay PC2 uses a common optocoupler for driving isolation. The output terminal of the optocoupler relay PC2 is connected to VLM+ through a resistor R5. The input terminal of the optocoupler relay PC2 is connected to a capacitor C4, a resistor R15, a resistor R14, and a diode D9, and then connected to the heating negative control terminal of the BMS main control. The second fast discharge circuit includes a transistor Q4, a resistor R7, and a diode D4. The base of the transistor Q4 is connected to a resistor R7, the collector is connected to the source of the MOSFET M2, and the emitter is connected to the diode D4. The other end of the resistor R7 is also connected to the source of the MOSFET M2. The other end of the diode D4 is connected to the output terminal of the optocoupler relay PC2. The emitter of the transistor Q4 is connected in parallel with a diode D6, a resistor R11, and a resistor R13. The other ends of the diode D6 and the resistor R11 are both connected to the source of the MOSFET M2, and the other end of the resistor R13 is connected to the gate of the MOSFET M2. Among them, resistor R5 is the output drive current limiting resistor, which controls the drive voltage switching of MOSFET M2 through optocoupler relay PC2; resistor R11 is the turn-off holding resistor for MOSFET M2; resistor R15 is the turn-off discharge resistor for optocoupler relay PC2; resistor R14 and diode D9 are connected to the positive terminal of optocoupler relay PC2 and controlled by the BMS main controller. A gate-source (GS) 0-level establishment resistor is provided; diode D6 is a GS overvoltage protection regulator; resistor R13 is the gate drive resistor for MOSFET M2, adjusting the drive rate to ensure that the positive and negative drives are essentially the same.

[0027] It can be understood that the lower (negative) side of the MOS drive circuit is a linear voltage regulator circuit composed of diode D1, resistor R1, capacitor C1, diode D2, resistor R2, resistor R3, transistor Q1, transistor Q2, and capacitor C3, which provides power; resistor R7, diode D4, and transistor Q4 form a fast discharge circuit when MOS transistor M2 is turned off, which accelerates the turn-off process of MOS transistor M2.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A novel PDU positive terminal MOS drive circuit, comprising a DC-DC isolation power supply module and a BMS master control, characterized in that, The DC-DC isolation power module input end is connected with the battery total positive end and total negative end respectively, the DC-DC isolation power module is powered by the battery, the output end of the DC-DC isolation power module outputs the power BMS12V+ and BGND and is connected with the BMS master control, and the BMS master control is provided with the power supply;And the DC-DC isolation power module positive input end is connected with MOS tube M1, and a DC module is used as the driving power supply of MOS tube M1, the input end of the DC module is connected with BMS12V+ through diode D11, and is connected with the charging end CHGA+ of the BMS master control through diode D12;The DC-DC isolation power module negative input end is connected with MOS tube M2, and a linear voltage stabilizing circuit and a second driving circuit are arranged to provide the driving source for MOS tube M2.

2. The novel PDU positive end MOS drive circuit according to claim 1, characterized in that, The DC-DC isolation power module positive input end is connected with switch SW1, which is used as an external switch to control the DC-DC isolation power module to enable;The switch SW2 is arranged between the DC-DC isolation power module positive input end and the BMS master control, and the BMS master control is controlled through the switch SW2 to realize the self-locking function after power-on.

3. The novel PDU positive end MOS drive circuit according to claim 1, characterized in that, The charging end CHGA+ and BGND of the BMS master control are connected with the charger to provide the auxiliary 12V power supply.

4. The novel PDU positive end MOS drive circuit according to claim 1, characterized in that, The DC module is connected with MOS tube M1 through the first driving circuit to control the switch of MOS tube M1;One end of the first driving circuit is connected with the DC module, and the other end is connected with the BMS master control.

5. The novel PDU positive end MOS drive circuit according to claim 4, characterized in that, The first driving circuit comprises a photo-coupler relay PC1 and a first fast discharge circuit, the photo-coupler relay PC1 is driven by a common photo-coupler;The first fast discharge circuit comprises a triode Q5, a resistor R17 and a diode D10, the base of the triode Q5 is connected with the resistor R17, the collector is connected with the source of MOS tube M1, and the emitter is connected with the diode D10, and the other end of the resistor R17 is also connected with the source of MOS tube M1.

6. The novel PDU positive end MOS drive circuit according to claim 5, characterized in that, The output positive end and the output negative end of the DC module are connected with the capacitor C2, the capacitor C2 is a driving power filter capacitor, the output positive end of the DC module is connected with the emitter of triode Q3 through diode D3, the emitter and the base of the triode Q3 are provided with the resistor R4, the base is connected with the output end of the photo-coupler relay PC1 through the resistor R6, the collector is connected with the resistor R8 and the diode D5 in turn, and then is connected with the diode D10 and the resistor R17;The input end of the photo-coupler relay PC1 is connected with the resistor R10, the capacitor C5, the resistor R16 and the diode D8, and then is connected with the heating positive control end of the BMS master control;The triode Q3, the resistor R4, the resistor R6 and the photo-coupler relay PC1 form a positive MOS driving power switch circuit to control the opening and closing of the driving voltage between the gate and the source of MOS tube M1.

7. The novel PDU positive end MOS drive circuit according to claim 1, characterized in that, One end of the linear voltage stabilizing circuit is connected with the DC-DC isolation power module, and the other end is connected with MOS tube M2;One end of the second driving circuit is connected with the BMS master control, and the other end is connected with MOS tube M2;And the linear voltage stabilizing circuit and the second driving circuit are connected with VLM+ at the same time.

8. The novel PDU positive end MOS drive circuit according to claim 7, characterized in that, The linear voltage stabilizing circuit comprises an anti-reverse diode D1, a triode Q1 and a triode Q2, one end of the diode D1 is connected with a DC-DC isolation power module, the other end of the diode D1 is connected with a resistor R1, a resistor R2 and a resistor R3, the other end of the resistor R1 is connected with a capacitor C1 and a base of the triode Q1, the other end of the resistor R2 is connected with a collector of the triode Q2, the other end of the resistor R3 is connected with a collector of the triode Q1; the other end of the capacitor C1 is connected with a diode D2 and a capacitor C3, the other end of the diode D2 is connected with the base of the triode Q1, the other end of the capacitor C3 is connected with VLM+; the base of the triode Q2 is connected with an emitter of the triode Q1, the emitter of the triode Q2 is connected with VLM+.

9. The novel PDU positive end MOS drive circuit according to claim 8, characterized in that, The second driving circuit comprises a photo-coupler relay PC2 and a second fast bleed circuit, the photo-coupler relay PC2 is driven and isolated by a common photo-coupler, an output end of the photo-coupler relay PC2 is connected with VLM+ through a resistor R5, an input end of the photo-coupler relay PC2 is connected with a capacitor C4, a resistor R15, a resistor R14 and a diode D9, and then connected with a heating negative control end of the BMS master control; the second fast bleed circuit comprises a triode Q4, a resistor R7 and a diode D4, a base of the triode Q4 is connected with the resistor R7, a collector of the triode Q4 is connected with a source of a MOS tube M2, an emitter of the triode Q4 is connected with the diode D4, the other end of the resistor R7 is also connected with the source of the MOS tube M2, the other end of the diode D4 is connected with an output end of the photo-coupler relay PC2, and the emitter of the triode Q4 is connected in parallel with a diode D6, a resistor R11 and a resistor R13, the other end of the diode D6 and the resistor R11 is connected with the source of the MOS tube M2, the other end of the resistor R13 is connected with a gate of the MOS tube M2.

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