CN210867216U

CN210867216U - BMS charge and discharge MOS manages independent control's drive circuit

Info

Publication number: CN210867216U
Application number: CN201921712672.XU
Authority: CN
Inventors: 姚敦平; 江练勇; 熊细旺
Original assignee: Dongguan Fenggu Technology Co ltd
Current assignee: Saivante Systems
Priority date: 2019-10-12
Filing date: 2019-10-12
Publication date: 2020-06-26
Anticipated expiration: 2029-10-12

Abstract

The utility model belongs to the technical field of the battery management system technique and specifically relates to a BMS charge-discharge MOS manages independent control's drive circuit, it includes group battery, load, battery management system, the MOS pipe and the MOS pipe that discharges charge, the total positive pole of group battery is connected to the total negative pole of group battery behind load, the MOS pipe and the MOS pipe that discharges of establishing ties in proper order, battery management system is connected with level shift circuit, level shift circuit is connected with charge drive circuit and discharge drive circuit respectively, and charge drive circuit and the MOS union coupling that charges, discharge drive circuit and the MOS union coupling that discharges. The utility model discloses reduced control logic's complexity, the specially adapted charges or the occasion that the MOS pipe needs the independent control that discharges.

Description

BMS charge and discharge MOS manages independent control's drive circuit

Technical Field

The utility model belongs to the technical field of the battery management system technique and specifically relates to a BMS charge-discharge MOS manages independent control's drive circuit who indicates.

Background

In a low-voltage energy storage system, no more than 16 strings of battery cells are usually selected to form a battery pack, and a battery management system BMS matched with the battery pack usually selects MOS (metal oxide semiconductor) tubes as a protection device, because compared with a direct-current contactor, the MOS tubes with low voltage and high current have multiple selectable types and are low in cost. Generally, two groups of MOS tube arrays are selected to be connected in series with the cathode of the battery pack, and compared with the MOS tube arrays which are connected in series with the anode of the battery pack, the MOS tube array has the advantages of simple driving control, and higher safety and reliability.

The drive control circuit of the charge and discharge MOS tube is designed based on the totem-pole circuit principle, and is provided with a special drive chip and a drive circuit built through discrete elements. However, both have a drawback that the charging and discharging MOS transistors cannot be controlled individually, but are instead interrelated, for example, to turn on the charging MOS transistor, the discharging MOS transistor must be turned on first. Therefore, the complexity of controlling the charging and discharging MOS tube is increased, and the method is not suitable for occasions requiring the independent control of the charging and discharging MOS tube.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a BMS charge and discharge MOS manages independent control's drive circuit to the problem that prior art provided has reduced control logic's complexity, and the specially adapted charges or the occasion that MOS pipe needs the independent control that discharges.

In order to solve the technical problem, the utility model discloses a following technical scheme:

the utility model provides a pair of BMS charge-discharge MOS manages independent control's drive circuit, including group battery, load, battery management system, the MOS pipe that charges and the MOS pipe that discharges, the total positive pole of group battery is connected to the total negative pole of group battery behind load, the MOS pipe that charges and the MOS pipe that discharges in proper order, battery management system is connected with level shift circuit, level shift circuit is connected with charge drive circuit and discharge drive circuit respectively, charge drive circuit and the MOS union coupling that charges, discharge drive circuit and the MOS union coupling that discharges.

Wherein, the level conversion circuit comprises a chip U1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1 and a capacitor C2, the 10 th pin of the chip U1 is respectively connected with one end of the resistor R3 and one end of the resistor R6, the other end of the resistor R6 is connected with the B-end of the battery pack, the 14 th pin of the chip U1 is respectively connected with one end of the resistor R4 and one end of the resistor R5, the other end of the resistor R5 is connected with the B-end of the battery pack, one end of the resistor R1 is connected with the B-end of the battery pack, the other end of the resistor R1 is respectively connected with the 2 nd pin and the 8 th pin of the chip U1, one end of the capacitor C1 is connected with the B-end of the battery pack, the other end of the capacitor C1 is respectively connected with the VCC end and the 1 st pin of the chip U1, one end of the resistor R1 is connected with the first pin 9 and the other, one end of the capacitor C2 is connected with the B-end of the battery pack, and the other end of the capacitor C2 is connected with the VDD end; the 11 th pin of the chip U1 is connected with a discharge driving circuit, and the 13 th pin of the chip U1 is connected with a charge driving circuit.

The model of the chip U1 is CD40109 BPWR.

Wherein, the charging driving circuit comprises a resistor R, an optocoupler U, a resistor R, a zener diode Z, a diode D, a MOS tube Q, a capacitor C, a triode Q and a triode Q, one end of the resistor R is connected with the level conversion circuit, the 1 st pin of the optocoupler U at the other end of the resistor R is connected with the 2 nd pin of the optocoupler U, the B-end of the battery pack is connected with the 3 rd pin of the optocoupler U, the 4 th pin of the optocoupler U is connected with one end of the resistor R, the anode of the diode D is connected with the P + end, the cathode of the diode D is respectively connected with one end of the capacitor C, the cathode of the zener diode Z, one end of the resistor R and the drain electrode of the MOS tube Q, the other end of the capacitor C is simultaneously connected with the anode of the zener diode Z, the other end of the resistor R, one end, the other end of the resistor R11 is connected with the gate of the MOS transistor Q1, the source of the MOS transistor Q1 is connected with one end of the resistor R13, the other end of the resistor R13 is connected with the anode of the diode D2, the cathode of the diode D2 is respectively connected with the anode of the diode D3, one end of the resistor R14, the collector of the triode Q4 and the base of the triode Q5, the collector of the triode Q5 is connected with the base of the triode Q4, the emitter of the triode Q4 and the other end of the resistor R14 are respectively connected with the P-end, and the cathode of the diode D3 is respectively connected with the emitter of the triode Q5 and the gate of the charging MOS transistor.

The MOS transistor Q1 is a PMOS transistor.

The discharge driving circuit comprises a capacitor C3, a resistor R8, a triode Q2, a triode Q3, a resistor R12 and a capacitor C5, one end of a resistor R8 is connected with one end of a capacitor C3 and is connected with the level conversion circuit, the other end of the capacitor C3 is connected with the other end of a resistor R8, the other end of the resistor R8 is simultaneously connected with a base of a triode Q2 and a base of the triode Q3, a collector of the triode Q2 is connected with one end of the resistor R12, the other end of the resistor R12 is connected with a VDD end, two ends of the capacitor C5 are respectively connected with a B-end of the battery pack, a collector of the triode Q3 is connected with the B-end of the battery pack, an emitter of the triode Q2 is connected with an emitter of a triode Q3, and a common end of an emitter of the triode Q2 connected with an emitter of the triode Q3 is connected with.

Wherein, the battery pack is a lithium battery pack.

The utility model has the advantages that:

1. based on the totem pole circuit principle, the charging driving circuit and the discharging driving circuit are built by using discrete elements, so that the cost is low, and the popularization and the application are facilitated;

2. the charging MOS tube and the discharging MOS tube can be independently controlled and are not associated with each other, the control logic complexity is reduced, and the BMS protection reliability is favorably improved;

3. the battery pack is particularly suitable for photovoltaic power generation energy storage systems, and is used in occasions where the charging MOS tube needs to be independently turned on when the BMS is awakened after sleeping, so that the possibility of deep over-discharge of the battery pack caused by turning on the discharging MOS tube is avoided; 4. the charging driving circuit of the charging MOS tube gets electricity from the load side, increases rectification filtering and voltage-stabilizing amplitude limiting, protects the driving MOS tube Q1, and can also work reliably and stably under the condition of large fluctuation of load output current.

Drawings

Fig. 1 is the utility model discloses a BMS charge-discharge MOS manages independent control's drive circuit's functional block diagram.

Fig. 2 is the utility model discloses a BMS charge-discharge MOS manages independent control's drive circuit's circuit schematic diagram.

The reference numerals include:

101-level shift circuit 102-discharge drive circuit 103-charge drive circuit.

Detailed Description

In order to facilitate understanding of those skilled in the art, the present invention will be further described with reference to the following examples and drawings, which are not intended to limit the present invention. The present invention will be described in detail with reference to the accompanying drawings.

The utility model provides a BMS charge-discharge MOS manages independent control's drive circuit, includes group battery, load, battery management system, the MOS pipe that charges and the MOS pipe that discharges, the total positive pole of group battery is connected to the total negative pole of group battery behind load, the MOS pipe that charges and the MOS pipe that discharges in proper order in series, battery management system is connected with level shift circuit, level shift circuit is connected with charge drive circuit and discharge drive circuit respectively, and charge drive circuit is connected with the MOS pipe that charges, and discharge drive circuit is connected with the MOS pipe that discharges.

The level shift circuit comprises a chip U1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1 and a capacitor C2, wherein the 10 th pin of the chip U1 is respectively connected with one end of a resistor R3 and one end of a resistor R6, the other end of the resistor R6 is connected with the B-end of the battery pack, the 14 th pin of the chip U1 is respectively connected with one end of a resistor R4 and one end of a resistor R5, the other end of the resistor R5 is connected with the B-end of the battery pack, one end of a resistor R82 1 is connected with the B-end of the battery pack, the other end of the resistor R1 is respectively connected with the 2 nd pin and the 8 th pin of the chip U1, one end of a capacitor C1 is connected with the B-end of the battery pack, the other end of the capacitor C1 is respectively connected with the VCC end and the 1 st pin of the chip 1, one end of the resistor R2 is connected with the first pin 3615, the other end of the resistor R2 is connected with a VDD end, one end of the capacitor C2 is connected with a B-end of the battery pack, and the other end of the capacitor C2 is connected with the VDD end; the 11 th pin of the chip U1 is connected with a discharge driving circuit, and the 13 th pin of the chip U1 is connected with a charge driving circuit; the other end of the resistor R3 is connected with a discharge control pin DIS of the MCU of the battery management system, and the other end of the resistor R4 is connected with a charge control pin CHG of the MCU of the battery management system. Specifically, the level shift circuit is used for converting the VDD voltage (usually 3.3V) output by the MCU control into the VDD voltage (usually 12V) input by the charge driving circuit and the discharge driving circuit to satisfy the driving condition; the battery pack protection circuit is characterized in that the resistor R5 and the resistor R6 are selected to be pulled down to the B-end of the battery pack, the level is not fixed when the MCU output pin DIS and the CHG are suspended or in a high-resistance state, the low level can be ensured by the pull-down resistor, the charging MOS tube and the discharging MOS tube are prevented from being opened abnormally, and the reliability of a Battery Management System (BMS) is improved.

In the drive circuit for independent control of the charging and discharging MOS transistor of the BMS described in this embodiment, the model of the chip U1 is CD40109 BPWR.

The drive circuit for independent control of the BMS charging and discharging MOS transistor according to the present embodiment includes a resistor R7, an optocoupler U2, a resistor R8, a resistor R9, a zener diode Z9, a diode D9, an MOS transistor Q9, a capacitor C9, a transistor Q9, and a transistor Q9, wherein one end of the resistor R9 is connected to a 13 th pin of a chip U9 of the level shift circuit, a 1 st pin of the other end of the resistor R9 is connected to the 1 st pin of the optocoupler U9, a 2 nd pin of the optocoupler U9 is connected to a B-terminal of the battery pack, a 3 rd pin of the optocoupler U9 is connected to a P-terminal, a 4 th pin of the optocoupler U9 is connected to one end of the resistor R9, an anode of the diode D9 is connected to a P + terminal, a cathode of the diode D9 is respectively connected to one end of an end of a capacitor C9, a cathode of the other end of the diode D9, a drain of the other diode D36, The other end of the resistor R10, one end of the resistor R11 and the other end of the resistor R9, the other end of the resistor R11 is connected with the gate of the MOS transistor Q1, the source of the MOS transistor Q1 is connected with one end of the resistor R13, the other end of the resistor R13 is connected with the anode of the diode D2, the cathode of the diode D2 is connected with the anode of the diode D3, one end of the resistor R14, the collector of the triode Q4 and the base of the triode Q5, the collector of the triode Q5 is connected with the base of the triode Q4, the emitter of the triode Q4 and the other end of the resistor R14 are connected with the P-terminal, and the cathode of the diode D3 is connected with the emitter of the triode Q5 and the gate of the charging MOS.

In the drive circuit for independent control of the BMS charging and discharging MOS tube, the MOS tube Q1 is a PMOS tube.

The drive circuit for the independent control of the charging and discharging MOS tube of the BMS comprises a capacitor C3, a resistor R8, a triode Q2, the power supply circuit comprises a triode Q3, a resistor R12 and a capacitor C5, wherein one end of the resistor R8 is connected with one end of the capacitor C3 and is connected with the 11 th pin of a chip U1 of the level conversion circuit, the other end of the capacitor C3 is connected with the other end of the resistor R8, the other end of the resistor R8 is simultaneously connected with the base of a triode Q2 and the base of a triode Q3, the collector of the triode Q2 is connected with one end of a resistor R12, the other end of the resistor R12 is connected with the VDD end, two ends of the capacitor C5 are respectively connected with the VDD end and the B-end of a battery pack, the collector of the triode Q3 is connected with the B-end of the battery pack, the emitter of the triode Q2 is connected with the emitter of the triode Q3, and the common end of the emitter of the triode Q2 and the. Specifically, the discharge driving circuit is designed based on the totem-pole circuit principle, when a plurality of discharge MOS transistors are required to be driven to be connected in parallel in an array, a proper triode needs to be selected, and the resistor R12 is used for limiting the charging current of VDD to the junction capacitor of the discharge MOS transistor and protecting the triode Q2.

This embodiment a BMS charge and discharge MOS manages independent control's drive circuit, the group battery is the lithium cell group.

The utility model discloses a theory of operation:

according to the series connection position of the charging MOS tube and the discharging MOS tube in the battery pack loop, the discharging MOS tube adopts non-isolated drive, and the charging MOS tube adopts isolated drive. Based on the totem-pole circuit principle, a reliable and low-cost circuit scheme is selected to solve the problem of independent control of the charge and discharge MOS tube drive. The driving circuit reduces the complexity of control logic, is particularly suitable for occasions where the charging or discharging MOS tube needs to be controlled independently, and particularly in a photovoltaic power generation energy storage system, photovoltaic awakening needs to be carried out independently after BMS dormancy to open the charging MOS tube.

The charging driving circuit adopts an optocoupler U2 for isolated driving, controls the driving voltage of the charging MOS tube to get electricity from the load (or charger), and reaches the driving voltage meeting the requirement after rectification, MOS tube Q1 switch control and multiple resistance voltage division to supply to the charging MOS tube. The driving voltage calculation formula is as follows: ugs is approximately equal to R14 (Up-2 is equal to Ud)/(R13+ R14), wherein Up is the output voltage of the charger, and Ud is the forward conduction voltage drop of the diode. According to the output voltage range of the load (or a charger), the divider resistors R13 and R14 are reasonably selected, so that the Ugs is 10-18V, and the normal conduction requirement of the MOS transistor can be met. The discrete component diode D1, zener diode Z1, capacitor C4 and resistor R9 are added for the purpose of: when the output fluctuation of the load (or the charger) is large, the functions of shaping, limiting amplitude and limiting current are achieved, so that the MOS tube Q1 is protected, and the voltage withstand value of the type-selection Uds of the MOS tube Q1 is 2 times of the maximum output voltage of the load (or the charger). It can be found that the driving voltage for driving the charging MOS tube is referred to as P-, and the source electrode of the charging MOS tube is also connected with P-, so that the function of independently controlling the charging MOS tube is realized.

To photovoltaic power generation energy storage system, under the circumstances of BMS dormancy, light is more weak or overcast and rainy day in morning, and photovoltaic awakens up BMS back, and BMS can only open the charging tube earlier and charge, avoids opening discharge tube and consumes more electric quantity of battery, causes the battery degree of depth to put and permanent damage. The utility model discloses this problem of fine solution possesses very high practical value.

It should be noted that most of the lithium battery packs in fig. 1 are lithium battery packs formed by connecting in series different parallel ways and no more than 16 series of cells, a source electrode of a discharge MOS transistor is connected with a negative electrode B-end of the lithium battery pack, a source electrode of a charge MOS transistor is connected with a negative electrode P-end of a load (or a charger), and when the discharge MOS transistor is disconnected, the B-end and the P-end are not equipotential, that is, the negative electrode of the lithium battery pack and the negative electrode of the charger are not in common, but are in common with an anode P + end.

Therefore, the driving control voltage Ugs (refer to P-) of the charging MOS transistor, the driving control voltage Ugs (refer to B-) of the discharging MOS transistor, and the auxiliary power of the BMS is stepped down from the B + and B-of the battery pack and then supplied to the driving circuit. Therefore, the discharge MOS tube can be independently controlled to be switched on and switched off, and the switching-on and switching-off control of the charge MOS tube is premised on that the discharge MOS tube must be switched on first.

The above description is only for the preferred embodiment of the present invention, and the present invention is not limited to the above description, and although the present invention is disclosed in the preferred embodiment, it is not limited to the above description, and any person skilled in the art can make some changes or modifications to equivalent embodiments without departing from the scope of the present invention, but all the technical solutions of the present invention are within the scope of the present invention.

Claims

1. The utility model provides a BMS charges and discharges MOS manages independent control's drive circuit which characterized in that: including group battery, load, battery management system, the MOS pipe and the MOS pipe that discharges charge, the total positive pole of group battery is connected to the total negative pole of group battery behind load, the MOS pipe and the MOS pipe that discharges of establishing ties in proper order, battery management system is connected with level switching circuit, level switching circuit is connected with charge drive circuit and discharge drive circuit respectively, and charge drive circuit is connected with the MOS pipe that charges, and discharge drive circuit is connected with the MOS pipe that discharges.

2. The BMS charging and discharging MOS tube independent control drive circuit according to claim 1, wherein: the level conversion circuit comprises a chip U1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a capacitor C1 and a capacitor C2, wherein the 10 th pin of the chip U1 is respectively connected with one end of the resistor R3 and one end of the resistor R6, the other end of the resistor R6 is connected with the B-end of the battery pack, the 14 th pin of the chip U1 is respectively connected with one end of the resistor R4 and one end of the resistor R5, the other end of the resistor R5 is connected with the B-end of the battery pack, one end of the resistor R1 is connected with the B-end of the battery pack, the other end of the resistor R1 is respectively connected with the 2 nd pin and the 8 th pin of the chip U1, one end of the capacitor C1 is connected with the B-end of the battery pack, the other end of the capacitor C1 is respectively connected with the VCC end and the 1 st pin of the chip U1, one end of the resistor R1 is connected with the VDD end of the VDD 1, the other end of the capacitor C2 is connected with a VDD end; the 11 th pin of the chip U1 is connected with a discharge driving circuit, and the 13 th pin of the chip U1 is connected with a charge driving circuit.

3. The BMS charging and discharging MOS tube independent control drive circuit according to claim 2, wherein: the model of the chip U1 is CD40109 BPWR.

4. The BMS charging and discharging MOS tube independent control drive circuit according to claim 1, wherein: the charging driving circuit comprises a resistor R, an optocoupler U, a resistor R, a voltage stabilizing diode Z, a diode D, an MOS tube Q, a capacitor C, a triode Q and a triode Q, wherein one end of the resistor R is connected with a level conversion circuit, the 1 st pin of the optocoupler U at the other end of the resistor R is connected with the 2 nd pin of the optocoupler U, the B-end of a battery pack is connected with the 2 nd pin of the optocoupler U, the 3 rd pin of the optocoupler U is connected with the P-end, the 4 th pin of the optocoupler U is connected with one end of the resistor R, the anode of the diode D is connected with the P + end, the cathode of the diode D is respectively connected with one end of the capacitor C, the cathode of the voltage stabilizing diode Z, one end of the resistor R and the drain electrode of the MOS tube Q, the other end of the, the other end of the resistor R11 is connected with the gate of the MOS transistor Q1, the source of the MOS transistor Q1 is connected with one end of the resistor R13, the other end of the resistor R13 is connected with the anode of the diode D2, the cathode of the diode D2 is respectively connected with the anode of the diode D3, one end of the resistor R14, the collector of the triode Q4 and the base of the triode Q5, the collector of the triode Q5 is connected with the base of the triode Q4, the emitter of the triode Q4 and the other end of the resistor R14 are respectively connected with the P-end, and the cathode of the diode D3 is respectively connected with the emitter of the triode Q5 and the gate of the charging MOS transistor.

5. The BMS charging and discharging MOS tube independent control drive circuit according to claim 4, wherein: the MOS transistor Q1 is a PMOS transistor.

6. The BMS charging and discharging MOS tube independent control drive circuit according to claim 1, wherein: the discharge driving circuit comprises a capacitor C3, a resistor R8, a triode Q2, a triode Q3, a resistor R12 and a capacitor C5, one end of the resistor R8 is connected with one end of the capacitor C3 and connected with the level conversion circuit, the other end of the capacitor C3 is connected with the other end of the resistor R8, the other end of the resistor R8 is simultaneously connected with the base of the triode Q2 and the base of the triode Q3, the collector of the triode Q2 is connected with one end of the resistor R12, the other end of the resistor R12 is connected with the VDD end, two ends of the capacitor C5 are respectively connected with the VDD end and the B-end of the battery pack, the collector of the triode Q3 is connected with the B-end of the battery pack, the emitter of the triode Q2 is connected with the emitter of the triode Q3, and the common end of the emitter of the triode Q2, which is connected with the emitter of.

7. The BMS charging and discharging MOS tube independent control drive circuit according to claim 1, wherein: the battery pack is a lithium battery pack.