CN115912562A - Control device for supporting multi-machine parallel charging and discharging of battery BMS, control method and working mode thereof - Google Patents
Control device for supporting multi-machine parallel charging and discharging of battery BMS, control method and working mode thereof Download PDFInfo
- Publication number
- CN115912562A CN115912562A CN202211565259.1A CN202211565259A CN115912562A CN 115912562 A CN115912562 A CN 115912562A CN 202211565259 A CN202211565259 A CN 202211565259A CN 115912562 A CN115912562 A CN 115912562A
- Authority
- CN
- China
- Prior art keywords
- discharging
- battery
- charging
- module
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Landscapes
- Secondary Cells (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a control device for supporting multi-machine parallel charging and discharging of a battery BMS, a control method and a working mode thereof. The voltage comparison module is mainly used for comparing the voltage difference between the internal voltage of the battery and the P +/C +, P-/C-output voltage; the output switch module is used for turning off the charging and discharging functions of the battery in the transportation process, namely turning off the charging and discharging MOS; when the connection is good in the load system, an output switch signal is required to inform that the battery pack can be opened to output at the moment; the charger identification module is used for transmitting a signal to the BMS when the charger is connected to identify and confirm that the charger is normally connected; the unidirectional weak discharge module circuit ensures that weak discharge can be carried out only through the circuit and charging cannot be carried out; and the AFE module of the BMS module is in communication connection with the MCU for information interaction. The invention is used for solving the problems of high cost or safety risk in the prior art.
Description
Technical Field
The invention belongs to the technical field of batteries; in particular to a control device for supporting multi-machine parallel charging and discharging of a battery BMS, a control method and a working mode thereof.
Background
The lithium ion battery can be safely used after being subjected to charge and discharge management by the BMS. Otherwise, the out-of-specification use has certain safety risk. The lithium ion battery is called a lithium ion battery PACK after passing through the BMS and the PACK, and is called the battery PACK for short. The normal battery pack can only be used by being connected with a load and a charger independently and cannot be charged and discharged in parallel. However, in the consumer market, a plurality of battery packs are often required to be flexibly connected in parallel for capacity expansion so as to meet the capacity requirements of different consumers. However, the battery pack generally belongs to an uncontrolled power source, and the BMS generally has no voltage and current limiting function and only performs voltage and current protection. Different battery packs may have different states, such as different SOC states and different protection states, and when a plurality of battery packs are directly connected in parallel, the plurality of battery packs may be subjected to uncontrolled mutual heavy current filling, so that safety risk is caused. Meanwhile, when different loads are met, the parallel batteries can work normally, for example, the batteries connected in parallel with motors or inductive loads are ensured to absorb recharging energy at any time, and the bus device is prevented from being damaged due to unabsorbed high voltage.
The existing market schemes generally comprise the following items: the first method is to use a common battery pack, and if a plurality of batteries are required to be connected in parallel, an external control board is required to manage the two batteries and limit the mutual filling risk between the two batteries. The board consists of a power board module, a management MCU and a communication module. The plate is typically of a relatively large size because the large current return paths of the battery pack pass through the plate, and power devices are required to turn the battery return paths on and off. Each battery access requires a separate power loop control, and more batteries connected in parallel require more power control loops. There is room in the general product to add the board, and the cost of the board will far exceed the cost of BMS, resulting in the increase of unit price of the product.
In the second method, a current limiting module is arranged in the battery pack or outside the battery pack, and the allowed charging and discharging current is limited within an allowed bearing range, so that the battery pack becomes a controlled power supply. Generally, the current limiting module is a bidirectional DCDC module, and a battery pack used with a large current needs a large power, has a large volume and has problems of cost and heat generation. Meanwhile, for the load of the motor, because the load has feedback charging (such as braking of the electric bicycle or downhill), the voltage of the port is greatly increased because the DCDC current-limiting function cannot completely absorb feedback energy, and finally, the high voltage breaks down an electric device to complete energy release, so that great safety risk is generated.
The third method comprises the following steps: and removing the power module on the basis of the first method, reserving the MCU and the communication module, mainly communicating the parallel battery packs, knowing the states of the battery packs, and coordinating a power switch on the battery pack BMS through a communication command to perform parallel operation logic. The scheme is low in cost, an extra circuit board is still needed to be installed, meanwhile, high requirements are placed on the stability of the control board and the reliability of software logic, and if information interaction delay, communication link failure, software logic error and the like exist, the parallel batteries can be trapped in great potential safety hazards.
Disclosure of Invention
The invention provides a control device for a battery BMS (battery management system) supporting multi-machine parallel charging and discharging, which is used for solving the problems of high cost or safety risk in the prior art.
The invention provides a control method of a control device for supporting multi-machine parallel charging and discharging of a battery BMS, which is used for solving the problems of high cost or safety risk in the prior art.
The invention provides a working mode of a control device for supporting multi-machine parallel charging and discharging of a battery BMS, which is used for solving the problems of high cost or safety risk in the prior art.
The invention is realized by the following technical scheme:
a control device for a battery BMS (Battery management System) supporting multi-machine parallel charging and discharging comprises a BMS module, a voltage comparison module, an output switch module, a charger identification module and a one-way weak discharging module;
the voltage comparison module is mainly used for comparing the voltage difference between the internal voltage of the battery and the P +/C +, P-/C-output voltage;
the output switch module is used for turning off the charging and discharging functions of the battery in the transportation process, namely turning off the charging and discharging MOS; when the connection is good in the load system, an output switch signal is required to inform that the battery pack can be opened to output at the moment;
the charger identification module is used for transmitting a signal to the BMS when the charger is connected to identify and confirm that the charger is normally connected;
the unidirectional weak discharge module circuit ensures that weak discharge can be carried out only through the circuit and charging cannot be carried out;
and the AFE module of the BMS module is in communication connection with the MCU for information interaction.
A battery BMS supports multi-machine parallel charging and discharging control devices, each control device comprises a BMS module, a voltage comparison module, an output switch module, a charger identification module and a unidirectional weak discharging module;
the BMS module comprises a battery, an MCU, an MOS triode Q1, an MOS triode Q2, a fuse F1 and an AFE module, wherein the end 1 of the AFE module is respectively connected with one end of the battery and one end of the fuse F1, and the other end of the fuse F1 is connected with the end P + \ C +; the No. 2 end of the AFE module is respectively connected with the other end of the battery, the grounding end, the S pole of the MOS triode Q1 and one end of the unidirectional weak discharge module, the G pole of the MOS triode Q1 is connected with the No. 10 end of the AFE module, the D pole of the MOS triode Q1 is connected with the S pole of the MOS triode Q2, the G pole of the MOS triode Q2 is connected with the No. 9 end of the AFE module, and the D pole of the MOS triode Q2 is respectively connected with the other end of the unidirectional weak discharge module, one end of the voltage comparison module and the P- \\ C-end;
no. 3 end of AFE module is connected with VCC and MCU's No. 3 end respectively, 4, 5, 6, 7 ends of AFE module are connected with MCU's 4, 5, 6, 7 ends respectively, 8 ends of AFE module are connected with GND and MCU's 8 ends respectively, MCU's 9 ends are connected with the other end of voltage comparison module, voltage comparison module's third end ground, MCU's 1 end is connected with charger identification module's one end, charger identification module's the other end is connected with the charger input signal end, MCU's 2 ends is connected with output switch module's one end, output switch module's the other end is connected with battery output switch signal end.
A battery BMS supports the control device of multi-machine parallel charging and discharging, the unidirectional weak discharging module comprises an MOS triode Q3, a resistor R1 and a diode D1, the S pole of the MOS triode Q3 is respectively connected with the No. 2 end of an AFE module, the other end of a battery, a grounding end and the S pole of the MOS triode Q1, the G pole of the MOS triode Q3 is connected with the No. 10 end of an MCU, the D pole of the MOS triode Q3 is connected with one end of the resistor R1, the other end of the resistor R1 is connected with the cathode of the diode D1, and the anode of the diode D1 is respectively connected with the D pole of the MOS triode Q2, one end of a voltage comparison module and the P \ C-end.
When a plurality of control devices are connected in parallel, a plurality of P + -C + ends are connected and then lead out a P + -C + end, a plurality of chargers are connected with input signal ends and then lead out a charger to be connected with the input signal ends, a plurality of battery output switch signal ends are connected and then lead out a battery output switch signal, and a plurality of P + -C-ends are connected and then lead out a P + -C-end.
A battery BMS supports the operating method of the controlling device that the multimachine connects the charging and discharging in parallel, the working mode of the said controlling device includes idle mode, discharge mode and charge mode specifically, there is discharge switch signal in the said idle mode, change over into the discharge mode when there is no charge signal, change over into the charge mode when there is no discharge switch signal in the said idle mode, there is charge signal;
when the discharging mode has no discharging switch signal and no charging signal, the discharging mode is switched to an idle mode; when the charging mode has no discharging switch signal, the charging mode is switched to an idle mode when no charging signal exists;
when the discharging mode has no discharging switch signal, the charging mode is switched to be the charging mode when the charging signal exists; when the charging mode has the discharging switch signal, the discharging mode is switched to when the charging mode has no charging signal.
A working method of a control device for supporting multi-machine parallel charging and discharging of a battery BMS is provided, the working mode of the control device specifically comprises an idle mode, a discharging mode and a charging mode,
the idle mode is specifically that the battery does not enter a discharging mode and a charging mode, and the MCU does not detect KEY and the charger identification signal CHG _ DET signal. The charging and discharging of the battery are closed, and the battery does not have the charging and discharging capabilities;
the discharging mode is specifically that the battery receives a signal of the output switch, the MCU detects a KEY signal, and meanwhile, the charger is not identified, namely, no charger identification signal CHG _ DET exists, and the battery is in a discharging state and has the capability of absorbing feedback charging of equipment;
the charging mode is specifically that when the charger is connected, the MCU detects a charger identification signal CHG _ DET signal, and the battery has unidirectional weak discharging capability and charging capability but does not have strong discharging capability.
A control method of a control device for supporting multi-machine parallel charging and discharging of a battery BMS is provided, which comprises the following steps,
based on the same-port BMS framework, a voltage comparison module, an output switch module, a charger identification module and a one-way weak discharge module are added and assembled;
when the battery is not connected to the load and no output switch signal is connected, the battery pack is in an idle mode, the battery pack cannot be discharged or charged, and the discharging FET MOS triode Q1, the charging FET MOS triode Q2 and the one-way weak discharging MOS triode Q3 are all closed;
when the output signals of the batteries are detected, all the batteries connected in parallel detect KEY signals, the battery pack enters a discharging mode, the discharging function of the battery pack is started, the MOS triode Q1 is opened, but the MOS triode Q2 and the MOS triode Q3 are closed; the voltage of the P +/C + and P-/C-bus is determined by the battery voltage in the high SOC state;
at the moment, the BMS detects a voltage comparison module to compare the voltage difference between the current battery and the external bus P +/C +, P-/C-; when the external voltage is higher than the battery voltage, the VOL _ DET outputs a signal, and the current battery pack does not start the MOS triode Q2 to charge the MOS, so that the possibility of large current being poured into other battery packs is avoided; the voltage comparison circuit of the battery pack with high electric quantity of the bus does not have a VOL _ DET signal, the voltage of the bus is judged to be consistent with the voltage of the battery, and an MOS triode Q2 is safely turned on to charge the MOS so as to absorb the regenerated charging current possibly existing in the bus at any time; if the voltages of a plurality of batteries connected with the bus are consistent, all the batteries detect that the bus voltage is close to the voltage of the batteries, the charging MOS triode Q2 is started, and the charging and discharging parallel operation state is completely started.
A control method of a control device for supporting multi-machine parallel charging and discharging of a battery BMS is characterized in that when the voltage of a current battery is close to bus voltage, or instant heavy current pulls down the bus, other low-voltage batteries are close to the bus voltage, the low-power battery also enters a discharging state, when discharging current exists, the BMS can forcibly turn on a charging MOS triode Q2 so as to reduce loop temperature rise, at the moment, the voltage of the battery is consistent with the bus, a voltage comparison module circuit VOL _ DET outputs a signal, the charging MOS triode Q2 is continuously turned on, and the battery enters a complete parallel operation state.
A battery BMS supports the control method of the controlling device that the multimachine connects the charging and discharging in parallel, when the charger inserts and BMS detects the charger identification signal CHG _ DET of the identification module of the charger has signals at the same time, BMS shifts to the charging mode; if the battery is in the discharging mode, the BMS exits from the discharging mode and is forced to be switched into the charging mode, and the charging mode has the highest priority; then the BMS starts the one-way weak discharging module and simultaneously closes a discharging loop of the MOS triode Q1, after the charger is connected, the system is prohibited from riding, and meanwhile, the one-way weak discharging module needs to continuously work to maintain the system to run for system power supply; meanwhile, after sufficient time delay, all bus batteries are ensured to be completely closed to discharge the MOS, and then all the batteries gradually open the charging MOS triode Q2;
at the moment, all the batteries on the system become batteries with unidirectional charging capacity, but the batteries do not have any discharging function; at the moment, the voltage output of the charger can be charged to a battery with low electric quantity preferentially, the bus voltage is determined by the battery with low electric quantity, and when the current battery has charging current, the discharging MOS triode Q1 is immediately opened to reduce the temperature rise of a loop; when the current disappears, the MOS triode Q1 is also closed, so that the bus can continuously keep the unidirectional current capability; as the lowest battery is gradually charged, the voltage of the bus is continuously increased, when the voltage of the bus exceeds the voltage of other batteries, the other batteries are charged, and finally all the batteries are uniformly fully charged;
if the BMS is in an idle mode before a charger is inserted, a charger identification signal CHG _ DET wakes up the BMS and simultaneously starts a one-way weak discharge module, then a discharge MOS triode Q1 is kept to be closed, a charge MOS triode Q2 is started to enter a one-way charge mode, the discharge MOS is driven to be opened when charging current exists, the voltage drop and the temperature rise of a loop are reduced, and the discharge MOS is closed in time when the charging current does not exist;
if the previous mode of the battery is the charging mode, but the KEY detects a signal at the same time; when the charger removes the charger identification signal CHG _ DET signal and disappears, the battery returns to the discharging mode, at the moment, the unidirectional weak discharging loop is continuously started to maintain the voltage use requirement of the bus, then the charging MOS triode Q2 is closed, and the discharging MOS triode Q1 is originally in a closed state; at the moment, the MOS triode Q1 and the MOS triode Q2 of the bus are both closed and return to an idle state, and the parallel operation logic has no charge and discharge capacity and is in a power-on state before the battery is started after sufficient time delay.
The beneficial effects of the invention are:
the invention has the advantages of safe and autonomous parallel connection, no quantity limitation, no need of a host, no need of an additional external circuit board, no need of information interaction with other batteries, no safety risk caused by communication link delay or failure, simple, safe and reliable parallel operation logic.
Each battery pack can independently realize parallel control, and a single battery or a plurality of batteries can normally work when being used in parallel.
The invention realizes the real convenient capacity expansion of the battery.
The invention can work under any load, can ensure that the load charged by feedback can be absorbed by the batteries after being connected in parallel, and has no safety risk in use.
When the batteries are in parallel discharge, the high-power battery can be discharged first, and when the power is close, the low-power battery 0 is connected to the bus for discharging in a delayed manner, so that the balance of the batteries and the capacity expansion are realized.
When the invention is charged, the low-power battery can be automatically charged in priority, and when the power of the low-power battery is consistent with that of the high-power battery, the low-power battery is merged into the bus for uniform charging; the balance among the batteries in the charging and discharging processes of the batteries is ensured.
Drawings
Fig. 1 is a circuit diagram for controlling charging and discharging according to the present invention.
Fig. 2 is a plurality of parallel circuit diagrams of the control of charging and discharging of the present invention.
Fig. 3 is a schematic diagram of the mode of operation of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A control device for a battery BMS (Battery management System) supporting multi-machine parallel charging and discharging comprises a BMS module, a voltage comparison module, an output switch module, a charger identification module and a one-way weak discharging module;
the voltage comparison module is mainly used for comparing the voltage difference between the internal voltage of the battery and the P +/C +, P-/C-output voltage; if the output voltage is higher than the battery voltage, the VOL _ DET signal output signal informs the MCU, for the protection of the negative terminal, as B + and P +/C + are connected through a fuse, only GND and P-/C-are needed to be compared, if GND is higher than P-/C-, the output voltage is higher than the battery voltage, and the VOL _ DET signal is sent to the MCU;
the output switch module is used for switching off the charging and discharging functions of the battery in the transportation process, namely, the charging and discharging MOS is switched off; when the connection is good in the load system, an output switch signal is required to inform that the battery pack can be opened to output at the moment; the general physical switch signal is a physical switch signal, and the module outputs a KEY signal to the MCU for identification when the MCU is started;
the charger identification module is used for transmitting a signal to the BMS when the charger is connected to identify and confirm that the charger is normally connected; such as a 5V or other voltage signal, or a switching signal for the BMS to recognize the charger access; after the conversion of the circuit, a charger identification signal CHG _ DET signal is output to the BMS for identification to confirm that the charger is normally connected;
the unidirectional weak discharge module circuit ensures that weak discharge can be carried out only through the circuit and charging cannot be carried out; the module circuit consists of an MOS triode Q3R 1D 1, and due to the existence of a D1 diode, the module circuit can ensure that the circuit can only discharge and cannot charge; meanwhile, because the existence of R1 generally takes the resistance within 10R-100R, the loop can only carry out weak discharge, but not strong discharge; the MOS triode Q3 is used for controlling the on-off of the weak discharge loop;
and the AFE module of the BMS module is in communication connection with the MCU for information interaction.
A battery BMS supports the control device that the multimachine connects the charging and discharging in parallel, every control device includes BMS module, voltage comparison module, output switch module, charger identification module and unidirectional weak discharge module;
the BMS module comprises a battery, an MCU, an MOS triode Q1, an MOS triode Q2, a fuse F1 and an AFE module, wherein the end 1 of the AFE module is respectively connected with one end of the battery and one end of the fuse F1, and the other end of the fuse F1 is connected with the end P + \ C +; the No. 2 end of the AFE module is respectively connected with the other end of the battery, the grounding end, the S pole of the MOS triode Q1 and one end of the unidirectional weak discharge module, the G pole of the MOS triode Q1 is connected with the No. 10 end of the AFE module, the D pole of the MOS triode Q1 is connected with the S pole of the MOS triode Q2, the G pole of the MOS triode Q2 is connected with the No. 9 end of the AFE module, and the D pole of the MOS triode Q2 is respectively connected with the other end of the unidirectional weak discharge module, one end of the voltage comparison module and the P- \\ C-end;
no. 3 end of AFE module is connected with VCC and MCU's No. 3 end respectively, 4, 5, 6, 7 ends of AFE module are connected with MCU's 4, 5, 6, 7 ends respectively, 8 ends of AFE module are connected with GND and MCU's 8 ends respectively, MCU's 9 ends are connected with the other end of voltage comparison module, voltage comparison module's third end ground, MCU's 1 end is connected with charger identification module's one end, charger identification module's the other end is connected with the charger input signal end, MCU's 2 ends is connected with output switch module's one end, output switch module's the other end is connected with battery output switch signal end.
A battery BMS supports the control device of the multi-machine parallel charging and discharging, the one-way weak discharging module comprises an MOS triode Q3, a resistor R1 and a diode D1, the S pole of the MOS triode Q3 is respectively connected with the No. 2 end of an AFE module, the other end of the battery, a grounding end and the S pole of the MOS triode Q1, the G pole of the MOS triode Q3 is connected with the No. 10 end of an MCU, the D pole of the MOS triode Q3 is connected with one end of the resistor R1, the other end of the resistor R1 is connected with the negative pole of the diode D1, and the positive pole of the diode D1 is respectively connected with the D pole of the MOS triode Q2, one end of a voltage comparison module and the P- \\ C-end.
When a plurality of control devices are connected in parallel, a plurality of P + \ C + ends are connected and then lead out a P + \ C + end, a plurality of chargers are connected and input signal ends are connected and then lead out a charger and are connected with an input signal end, a plurality of battery output switch signal ends are connected and then lead out a battery output switch signal, and a plurality of P- \ C-ends are connected and then lead out a P- \ C-end.
Parallel operation referring to FIG. 2, FIG. 2 illustrates a parallel connection of two batteries, wherein battery 1 and battery 2 are connected in parallel by P +/C +, P-/C-. The charger connection input signal and the battery output switch signal are also connected in parallel and are connected to the respective identification signals.
A battery BMS supports the operating method of the controlling device that the multimachine connects the charging and discharging in parallel, the working mode of the said controlling device includes idle mode, discharge mode and charge mode specifically, there is discharge switch signal in the said idle mode, change over into the discharge mode when there is no charge signal, change over into the charge mode when there is no discharge switch signal in the said idle mode, there is charge signal;
when the discharging mode has no discharging switch signal and no charging signal, the discharging mode is switched to an idle mode; when the charging mode has no discharging switch signal, the charging mode is switched to an idle mode when no charging signal exists;
when the discharging mode has no discharging switch signal, the charging mode is switched to the charging mode when the charging signal exists; when the charging mode has a discharging switch signal, the discharging mode is switched to when the charging mode has no charging signal.
A battery BMS supports the operating method of the controlling device that the multimachine connects the charging and discharging in parallel, the working mode of the said controlling device includes idle mode, discharge mode and charging mode specifically;
the idle mode is specifically that the battery does not enter a discharging mode and a charging mode, and the MCU does not detect KEY and the charger identification signal CHG _ DET signal. The charging and discharging of the battery are closed, and the battery does not have the charging and discharging capabilities;
the discharging mode is specifically that the battery receives a signal of the output switch, the MCU detects a KEY signal, and meanwhile, the charger is not identified, namely, no charger identification signal CHG _ DET exists, and the battery is in a discharging state and has the capability of absorbing feedback charging of equipment;
the charging mode is specifically that when the charger is connected, and the MCU detects a charger identification signal CHG _ DET signal, the battery has unidirectional weak discharging capability and charging capability, but does not have strong discharging capability.
A control method of a control device for supporting multi-machine parallel charging and discharging of a battery BMS is provided, which comprises the following steps,
based on a same-port BMS framework (the same-port BMS framework comprises a same-port high-edge BMS framework and a same-port bottom edge BMS framework), a fuse, an AFE module and an MCU module which are required by a normal BMS, and charge and discharge control consisting of an MOS triode Q1 and an MOS triode Q2 do not belong to the scope of the invention, and refer to fig. 1) a voltage comparison module, an output switch module, a charger identification module and a one-way weak discharge module are added and assembled;
when the battery is not connected to the load and no output switch signal is connected, the battery pack is in an idle mode, the battery pack cannot be discharged or charged, and the discharging FET MOS triode Q1, the charging FET MOS triode Q2 and the one-way weak discharging MOS triode Q3 are all closed; at the moment, a plurality of batteries are connected in parallel without potential safety hazard. There is no possibility of mutual flow of the batteries.
When a battery output signal is detected, all batteries connected in parallel detect a KEY signal, the battery pack enters a discharging mode, the battery pack starts a discharging function, the MOS triode Q1 is opened, but the MOS triode Q2 and the MOS triode Q3 are closed, so that the batteries with different electric quantities are prevented from mutually filling; the voltage of the P +/C + and P-/C-bus is determined by the battery voltage in the high SOC state;
at the moment, the BMS detects a voltage comparison module to compare the voltage difference between the current battery and the external bus P +/C +, P-/C-; when the external voltage is higher than the battery voltage, the VOL _ DET outputs a signal, and the current battery pack does not start the MOS triode Q2 to charge the MOS, so that the possibility of large current being poured into other battery packs is avoided; the voltage comparison circuit of the battery pack with high electric quantity of the bus does not have a VOL _ DET signal, the voltage of the bus is judged to be close to or consistent with the voltage of the battery, and an MOS triode Q2 is safely started to charge the MOS so as to absorb the regenerated charging current possibly existing in the bus at any time; if the voltages of a plurality of batteries connected with the bus are consistent, all the batteries detect that the bus voltage is close to the voltage of the batteries, the charging MOS triode Q2 is started, and the charging and discharging parallel operation state is completely started.
Therefore, if the voltages of the batteries in parallel operation are all inconsistent, the highest battery voltage is always judged to be the battery voltage which is more than or equal to the bus voltage, the charging MOS is selected to be started to enter a complete conduction state, so that the bus has the capability of absorbing, recovering and charging, if the voltages of other batteries are lower than the bus voltage, the charging MOS is selected to be closed, the unidirectional discharging capability is realized, meanwhile, the charging current cannot be injected by the high voltage of the bus, and if the voltages of other batteries are more than or equal to the bus voltage, the charging MOS can be started to enter the complete parallel operation state;
the process is a state in the starting process, and the decision output is generally finished in the starting 1S; if the batteries after parallel operation have discharge current, the high-voltage batteries are discharged firstly, then the voltage of the high-voltage batteries is gradually reduced to be consistent with that of the low-voltage batteries, and the low-voltage batteries have unidirectional discharge capacity;
a control method of a control device for supporting multi-machine parallel charging and discharging of a battery BMS is characterized in that when the voltage of a current battery is close to bus voltage, or instant heavy current pulls down the bus, other low-voltage batteries are close to the bus voltage, the low-power battery also enters a discharging state, when discharging current exists, the BMS can forcibly turn on a charging MOS triode Q2 so as to reduce loop temperature rise, at the moment, the voltage of the battery is consistent with the bus, a voltage comparison module circuit VOL _ DET outputs a signal, the charging MOS triode Q2 is continuously turned on, and the battery enters a complete parallel operation state.
A battery BMS supports the control method of the controlling device that the multimachine connects the charging and discharging in parallel, when the charger inserts and BMS detects the charger identification signal CHG _ DET of the identification module of the charger has signals at the same time, BMS shifts to the charging mode; if the charging mode is in the discharging mode, the BMS exits the discharging mode and is forced to be switched into the charging mode, and the charging mode has the highest priority; then the BMS starts the one-way weak discharging module and simultaneously closes a discharging loop of the MOS triode Q1, after the charger is connected, the system is prohibited from riding (safety regulation), and meanwhile, the one-way weak discharging module needs to continuously work to maintain the system to run for the system power supply, such as the work of an instrument and the like; meanwhile, after sufficient time delay, all bus batteries are ensured to be completely closed to discharge MOS (metal oxide semiconductor), generally 1s, and then all the batteries gradually open the charging MOS triode Q2;
at the moment, all the batteries on the system are changed into the batteries with unidirectional charging capability, but the batteries do not have any discharging function; at the moment, the voltage output of the charger can be charged to a battery with low electric quantity preferentially, the bus voltage is determined by the battery with low electric quantity, and when the current battery has charging current, the discharging MOS triode Q1 is immediately opened to reduce the temperature rise of a loop; when the current disappears, the MOS triode Q1 is also closed, so that the bus can continuously keep the unidirectional current capability; the voltage of the bus is continuously increased along with the gradual charging of the lowest battery, when the voltage of the lowest battery exceeds the voltage of other batteries, the other batteries are charged, and finally all the batteries are uniformly fully charged;
if the BMS is in an idle mode before a charger is inserted, a charger identification signal CHG _ DET wakes up the BMS and simultaneously starts a one-way weak discharge module, then a discharge MOS triode Q1 is kept to be closed, a charge MOS triode Q2 is started to enter a one-way charge mode, the discharge MOS is driven to be opened when charging current exists, the voltage drop and the temperature rise of a loop are reduced, and the discharge MOS is closed in time when the charging current does not exist;
if the previous mode of the battery is the charging mode, but the KEY detects a signal at the same time; when the charger removes the charger identification signal CHG _ DET signal and disappears, the battery returns to the discharging mode, at the moment, the unidirectional weak discharging loop is continuously started to maintain the voltage use requirement of the bus, then the charging MOS triode Q2 is closed, and the discharging MOS triode Q1 is originally in a closed state; at the moment, the MOS triode Q1 and the MOS triode Q2 of the bus are both closed and return to an idle state, and the parallel operation logic has no charge and discharge capacity, generally 1S after sufficient time delay and in a starting state before the battery is started;
and in the idle mode, a charging switch, a discharging switch and a weak discharging switch of the battery are all in a closed state, so that safety and reliability in parallel operation installation are realized.
When the output switch is identified, the discharging switch of the battery is opened, and the charging switch is only used when discharging current exists or no signal is output by the voltage comparison module, namely the battery voltage is greater than or equal to the bus voltage. And the charging MOS is opened, so that safe and reliable parallel operation is realized. The possibility of mutual filling among the batteries does not exist. Meanwhile, the highest battery voltage of the bus can be ensured to be started, and the regeneration charging capability of the bus can be absorbed at any time.
After the access of the charger is identified, unidirectional weak discharge is started, the power supply requirements of a control module, an instrument and the like of the bus are maintained, meanwhile, the discharge switch is closed, and the charge switch is started after short time delay to enter a unidirectional charge state. When charging current exists, the discharging switch is forcibly turned on, and when charging current does not exist, the discharging switch is turned off.
The negative end same-port protection is taken as an example for the BMS frame, but the invention is not limited to the BMS frame, and the invention is also suitable for the high-side same-port BMS.
The voltage comparison module can also use a comparison circuit to realize voltage comparison, and can also use software to collect P +/C +, C +/C-voltage, and then compare the P +/C +, C +/C-voltage with the total voltage of the battery through the software to realize the voltage comparison function. The method is also used in the protection scope of the invention.
TABLE 1MOS triode and BMS mode relation table
Claims (10)
1. A control device for supporting multi-machine parallel charging and discharging of a battery BMS is characterized by comprising a BMS module, a voltage comparison module, an output switch module, a charger identification module and a one-way weak discharging module;
the voltage comparison module is used for comparing the voltage difference between the internal voltage of the battery and the P +/C +, P-/C-output voltage;
the output switch module is used for turning off the charging and discharging functions of the battery in the transportation process, namely turning off the charging and discharging MOS; when the connection is good in the load system, an output switch signal is required to inform that the battery pack can be opened for output at the moment;
the charger identification module is used for transmitting a signal to the BMS when the charger is connected to identify and confirm that the charger is normally connected;
the unidirectional weak discharge module ensures that weak discharge can be carried out only through the circuit and charging cannot be carried out;
and the AFE module of the BMS module is in communication connection with the MCU for information interaction.
2. The control device of claim 1, wherein each control device comprises a BMS module, a voltage comparison module, an output switch module, a charger identification module, and a unidirectional weak discharge module;
the BMS module comprises a battery, an MCU, an MOS triode Q1, an MOS triode Q2, a fuse F1 and an AFE module, wherein the end 1 of the AFE module is respectively connected with one end of the battery and one end of the fuse F1, and the other end of the fuse F1 is connected with the end P + \ C +; the No. 2 end of the AFE module is respectively connected with the other end of the battery, the grounding end, the S pole of the MOS triode Q1 and one end of the unidirectional weak discharge module, the G pole of the MOS triode Q1 is connected with the No. 10 end of the AFE module, the D pole of the MOS triode Q1 is connected with the S pole of the MOS triode Q2, the G pole of the MOS triode Q2 is connected with the No. 9 end of the AFE module, and the D pole of the MOS triode Q2 is respectively connected with the other end of the unidirectional weak discharge module, one end of the voltage comparison module and the P- \\ C-end;
no. 3 end of AFE module is connected with VCC and MCU's No. 3 end respectively, 4, 5, 6, 7 ends of AFE module are connected with MCU's 4, 5, 6, 7 ends respectively, 8 ends of AFE module are connected with GND and MCU's 8 ends respectively, MCU's 9 ends are connected with the other end of voltage comparison module, voltage comparison module's third end ground, MCU's 1 end is connected with charger identification module's one end, charger identification module's the other end is connected with the charger input signal end, MCU's 2 ends is connected with output switch module's one end, output switch module's the other end is connected with battery output switch signal end.
3. The control device of claim 2, wherein the one-way weak discharge module comprises a MOS transistor Q3, a resistor R1 and a diode D1, wherein the S-pole of the MOS transistor Q3 is connected to the 2-terminal of the AFE module, the other terminal of the battery, the ground terminal and the S-pole of the MOS transistor Q1, respectively, the G-pole of the MOS transistor Q3 is connected to the 10-terminal of the MCU, the D-pole of the MOS transistor Q3 is connected to one terminal of the resistor R1, the other terminal of the resistor R1 is connected to the negative terminal of the diode D1, and the positive pole of the diode D1 is connected to the D-pole of the MOS transistor Q2, one terminal of the voltage comparison module and the P- \\ C-terminal, respectively.
4. The control device of claim 3, wherein when a plurality of control devices are connected in parallel, a plurality of P + \ C + terminals are connected and then lead out a P + \ C + terminal, a plurality of charger connection input signal terminals are connected and then lead out a charger connection input signal terminal, a plurality of battery output switch signal terminals are connected and then lead out a battery output switch signal, and a plurality of P- \ C-terminals are connected and then lead out a P- \ C-terminal.
5. The operating method of a control device for a battery BMS supporting multi-machine parallel charging and discharging according to any one of claims 1 to 4, wherein the operating mode of the control device specifically comprises an idle mode, a discharging mode and a charging mode, wherein the control device is switched to the discharging mode when the idle mode has a discharging switch signal and no charging signal, and is switched to the charging mode when the idle mode has no discharging switch signal and a charging signal;
when the discharging mode has no discharging switch signal and no charging signal, the discharging mode is switched to an idle mode; when the charging mode has no discharging switch signal, the charging mode is switched to an idle mode when no charging signal exists;
when the discharging mode has no discharging switch signal, the charging mode is switched to the charging mode when the charging signal exists; when the charging mode has the discharging switch signal, the discharging mode is switched to when the charging mode has no charging signal.
6. The operating method of the control device for supporting multi-machine parallel charging and discharging of the battery BMS according to claim 5, wherein the control device specifically comprises an idle mode, a discharging mode and a charging mode,
the idle mode is specifically that the battery does not enter a discharging mode and a charging mode, and the MCU does not detect KEY and CHG _ DET signals; the charging and discharging of the battery are closed, and the battery does not have the charging and discharging capabilities;
the discharging mode is specifically that the battery receives a signal of the output switch, the MCU detects the KEY signal, and meanwhile, the charger is not identified, namely, no CHG _ DET signal exists, and the battery is in a discharging state and has the capability of absorbing feedback charging of equipment;
the charging mode is specifically that when the charger is connected, the MCU detects a CHG _ DET signal, and the battery has unidirectional weak discharging capability and charging capability but does not have strong discharging capability.
7. The control method of the control device for a battery BMS supporting multi-machine parallel charging and discharging according to any one of claims 1 to 4, wherein the control method is specifically,
based on the same-port BMS framework, a voltage comparison module, an output switch module, a charger identification module and a one-way weak discharge module are added and assembled;
when the battery is not connected to the load and no output switch signal is connected, the battery pack is in an idle mode, the battery pack cannot be discharged or charged, and the discharging FET MOS triode Q1, the charging FET MOS triode Q2 and the unidirectional weak discharging MOS triode Q3 are all closed;
when the output signals of the batteries are detected, all the batteries connected in parallel detect KEY signals, the battery pack enters a discharging mode, the discharging function of the battery pack is started, the MOS triode Q1 is opened, but the MOS triode Q2 and the MOS triode Q3 are closed; the voltage of the P +/C + and P-/C-buses is determined by the battery voltage in a high SOC state;
at the moment, the BMS detects a voltage comparison module to compare the voltage difference between the current battery and the external bus P +/C +, P-/C-; when the external voltage is higher than the battery voltage, the VOL _ DET outputs a signal, and the current battery pack decides not to turn on the MOS triode Q2 to charge the MOS, so that the possibility that large current is poured into other battery packs is avoided; the voltage comparison circuit of the battery pack with high electric quantity of the bus does not have a VOL _ DET signal, the voltage of the bus is judged to be consistent with the voltage of the battery, and an MOS triode Q2 is safely turned on to charge the MOS so as to absorb the regenerated charging current possibly existing in the bus at any time; if the voltages of a plurality of batteries connected with the bus are consistent, all the batteries detect that the bus voltage is close to the voltage of the batteries, the charging MOS triode Q2 is started, and the charging and discharging parallel operation state is completely started.
8. The method as claimed in claim 7, wherein when the voltage of the battery is close to the bus voltage, or when a transient large current is applied to pull down the bus, other low voltage batteries are close to the bus voltage, the low battery enters a discharging state, and when a discharging current is applied, the battery BMS will force the charging MOS transistor Q2 to turn on to reduce the loop temperature rise, and when the voltage of the battery is consistent with the bus, the voltage comparison module VOL _ DET outputs a signal, and the charging MOS transistor Q2 is continuously turned on to enter a full parallel operation state.
9. The control method of the control device for the battery BMS supporting the multi-machine parallel charging and discharging according to claim 7, wherein when the charger is connected and the BMS detects that the CHG _ DET of the charger identification module has a signal, the BMS switches to a charging mode; if the charging mode is in the discharging mode, the BMS exits the discharging mode and is forced to be switched into the charging mode, and the charging mode has the highest priority; then the BMS starts the one-way weak discharging module and simultaneously closes a discharging loop of the MOS triode Q1, after the charger is connected, the system is prohibited from riding, and meanwhile, the one-way weak discharging module needs to continuously work to maintain the system to run for system power supply; meanwhile, after sufficient time delay, all bus batteries are ensured to be completely closed to discharge the MOS, and then all the batteries gradually open the charging MOS triode Q2;
at the moment, all the batteries on the system become batteries with unidirectional charging capacity, but the batteries do not have any discharging function; at the moment, the voltage output of the charger can be charged to a battery with low electric quantity preferentially, the bus voltage is determined by the battery with low electric quantity, and when the current battery has charging current, the discharging MOS triode Q1 is immediately opened to reduce the temperature rise of a loop; when the current disappears, the MOS triode Q1 is also closed, so that the bus can continuously keep the unidirectional current capability; as the lowest battery is gradually charged, the voltage of the bus is continuously increased, when the voltage of other batteries is exceeded, other batteries are also charged, and finally all the batteries are uniformly charged.
10. The method as claimed in claim 7, wherein if the BMS is in idle mode before the charger is inserted, the charger recognition signal CHG _ DET wakes up the BMS and simultaneously turns on the one-way weak discharging module, and then maintains the discharging MOS transistor Q1 off, turns on the charging MOS transistor Q2 to enter the one-way charging mode, drives the discharging MOS on when there is charging current, reduces the loop voltage drop and temperature rise, and turns off the discharging MOS in time when there is no charging current;
if the previous mode of the battery is the charging mode, but the KEY detects a signal at the same time; when the CHG _ DET signal is removed by the charger and disappears, the battery returns to a discharging mode, the unidirectional weak discharging loop is continuously started at the moment to maintain the voltage use requirement of the bus, then the charging MOS triode Q2 is closed, and the discharging MOS triode Q1 is originally in a closed state; at the moment, the MOS triode Q1 and the MOS triode Q2 of the bus are both closed and return to an idle state, and the parallel operation logic has no any charge and discharge capacity and is in a power-on state before the battery is started after sufficient time delay.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211565259.1A CN115912562A (en) | 2022-12-07 | 2022-12-07 | Control device for supporting multi-machine parallel charging and discharging of battery BMS, control method and working mode thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211565259.1A CN115912562A (en) | 2022-12-07 | 2022-12-07 | Control device for supporting multi-machine parallel charging and discharging of battery BMS, control method and working mode thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115912562A true CN115912562A (en) | 2023-04-04 |
Family
ID=86491228
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211565259.1A Pending CN115912562A (en) | 2022-12-07 | 2022-12-07 | Control device for supporting multi-machine parallel charging and discharging of battery BMS, control method and working mode thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115912562A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117728551A (en) * | 2024-02-07 | 2024-03-19 | 绿进新能源科技(常熟)有限公司 | BMS (Battery management System) for realizing parallel connection of master pack and slave pack of battery pack, method and battery pack with BMS |
| CN117879119A (en) * | 2024-03-13 | 2024-04-12 | 深圳市沃尔德储能技术有限公司 | Control system and method for capacity expansion of energy storage power supply |
-
2022
- 2022-12-07 CN CN202211565259.1A patent/CN115912562A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117728551A (en) * | 2024-02-07 | 2024-03-19 | 绿进新能源科技(常熟)有限公司 | BMS (Battery management System) for realizing parallel connection of master pack and slave pack of battery pack, method and battery pack with BMS |
| CN117728551B (en) * | 2024-02-07 | 2024-04-26 | 绿进新能源科技(常熟)有限公司 | BMS (Battery management System) for realizing parallel connection of master pack and slave pack of battery pack, method and battery pack with BMS |
| CN117879119A (en) * | 2024-03-13 | 2024-04-12 | 深圳市沃尔德储能技术有限公司 | Control system and method for capacity expansion of energy storage power supply |
| CN117879119B (en) * | 2024-03-13 | 2024-05-17 | 深圳市沃尔德储能技术有限公司 | Control system and method for capacity expansion of energy storage power supply |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6462027B2 (en) | Energy storage system for electric or hybrid vehicles | |
| CN101199094B (en) | Electric power storage system | |
| CN115912562A (en) | Control device for supporting multi-machine parallel charging and discharging of battery BMS, control method and working mode thereof | |
| CN104247198A (en) | Power supply system and charging and discharging control method for power supply system | |
| CN102195333A (en) | Direct-current power source apparatus | |
| CN102431464A (en) | Switched battery and capacitor arrangement and related operating methods | |
| CN105034991A (en) | Vehicle power grid and method for operating the vehicle power grid | |
| KR20200024227A (en) | System and method for operating a dual battery system | |
| CN113954686A (en) | Battery pack, battery management system and vehicle | |
| CN111682626A (en) | BMS battery management system and management method suitable for energy storage cabinet | |
| CN211567861U (en) | Automatic power supply device for storage battery of electric vehicle | |
| CN211320956U (en) | Charging and discharging circuit and charging and discharging system of online power supply | |
| CN115366833B (en) | Redundant power supply controller of mine unmanned vehicle | |
| CN104300605A (en) | Power circuit and control method thereof | |
| CN215883385U (en) | Battery pack, battery management system and vehicle | |
| CN218829200U (en) | Control device for battery BMS (Battery management System) supporting multi-machine parallel charging and discharging | |
| US20240106260A1 (en) | Intelligent energy storage system | |
| Li et al. | Evaluation of a module-integrated distributed battery energy storage system | |
| CN115549264A (en) | Battery management system and charge equalization control method | |
| CN115320377A (en) | Power system for vehicle | |
| CN114655071A (en) | Battery, battery control method and electric vehicle | |
| CN114400751A (en) | Battery group parallel system, control method and storage medium | |
| CN113131076A (en) | Battery system capable of being expanded in parallel | |
| CN115051451B (en) | Multi-stage battery combiner and control method | |
| CN114788118A (en) | Integration of battery and supercapacitor in an on-board power system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |