KR101974807B1 - Smart slave battery management system and method for battery management thereof - Google Patents

Abstract

The present invention provides a smart slave battery management system and a driving method thereof which can be operated without stopping the system even if a problem occurs in a master BMS unlike conventional battery management systems, and has improved stability, and increased precision and speed compared to conventional systems. The battery management system formed with a plurality of battery cells electrically connected mutually and managing a plurality of battery packs electrically connected mutually includes a plurality of smart slave SMSs, which measure and calculate data on the electrical characteristics of the battery packs each user manages in real time and monitor the state of each other in real time by communicating the measured and calculated data in real time by mutual communication and storing and updating the inside of each user. In this case, one of the smart slave BMSs is arbitrarily selected as a master mode smart slave BMS and controls the battery management system by storing and processing the measured and calculated data from each of remaining smart slave BMSs.

Description

Smart Slave Battery Management System and its Battery Management Method {SMART SLAVE BATTERY MANAGEMENT SYSTEM AND METHOD FOR BATTERY MANAGEMENT THEREOF}

The present invention relates to a battery management system (Battery Management System: "BMS"), in particular, even when a problem occurs in the master BMS can be operated without stopping the system, smart slave battery management improved stability and improved precision and speed It's about the system.

The present invention also relates to a battery management method of the system.

A rechargeable battery capable of charging and discharging, such as a lithium ion battery, and having electrical characteristics such as high energy density is suitable for application to mobile devices and devices such as electric vehicles because it can be manufactured in an eco-friendly, small, and lightweight manner.

In particular, in order to obtain a high output required in the application of an electric vehicle, the secondary battery is composed of a plurality of unit cells are electrically connected to each other. Such unit cells generally include components such as a positive electrode and a negative electrode current collector, a separator, an active material, an electrolyte, and the like, and may be repeatedly charged and discharged by an electrochemical reaction therebetween. In addition, the assembly of a plurality of interconnected unit cells form one battery pack, and such battery packs are typically provided in plural and are connected in parallel to each other to form one battery pack system as a whole.

And, in the battery pack system, the physical state of these cells or battery packs senses their voltage, current, and temperature through sensors attached to each battery pack, and based on this data, a so-called Battery Management System: " BMS ") monitors and controls the state of the cell or battery pack. The BMS includes, for example, power supply control for the driving load of each battery pack, measurement of electrical characteristics of current and voltage, charge / discharge control, voltage equalization control to reduce voltage difference between cells, and state of charge. Estimation of " SOC "

Such a BMS is generally designed in a so-called master-slave BMS scheme, which is separately composed of a master BMS and a plurality of slave BMSs attached to a battery pack and mainly detecting its state. In general, the sensing measurement function is performed by a plurality of slave BMSs as described below, and the control and calculation estimation function receives the data sensed by the master BMS from the slave BMSs and monitors the state of the battery based thereon. By controlling.

1A and 1B show a configuration diagram of a conventional battery pack system, which will be described in more detail with reference to these drawings.

First, in the conventional battery pack system shown in FIG. 1A, each slave BMS 20A is electrically connected to a plurality of battery packs 30A composed of a plurality of batteries or unit cells 40A, respectively, and thus the state of the battery 40A. (E.g., voltage, current and temperature). The slave BMS 20A transmits these state data to the master BMS 10A, and the master BMS 10A controls each battery 40A based on this. An example of related prior art is Korean Patent Publication No. 10-2012-0037163.

However, in such a system, since the master BMS 10A and the plurality of slave BMSs 20A are located on separate circuit boards independently of each other and directly connected to each other, the larger the system capacity, the more slave boards and more wires. Cable is required. Thus, this leads to difficulty in maintenance due to lower productivity, increased manufacturing cost, as well as physical damage and poor electrical connection of the wire.

On the other hand, as shown in FIG. 1B, a circuit board of the master BMS 10B and a plurality of slave BMSs 20B each arranged in a chain shape are connected to each other through a so-called daisy chain 70B, which is a serial communication network. There is a way. An example of the related art is Korean Patent No. 10-1540086.

Here, each slave BMS 20B measures the battery status of the corresponding battery pack 30B and sequentially inputs its data from the highest slave BMS 20B to the lowest slave BMS 20B one by one through the daisy chain 70B. In the same way as before, the control signals from the master BMS 10B calculated based on the received data are sequentially transmitted through the daisy chain 70B. Is transmitted to each slave BMS 20B from the top to the bottom.

However, in this case, when the master BMS 10B, which functions as a control and arithmetic function, fails to perform a normal operation due to a failure state (for example, a power out or a software bug occurs), the entire system is stopped. Occurs.

This system shutdown causes serious problems such as battery deterioration by completely shutting off the power supply from the system or generating an abnormal voltage until the problem is solved.

The present invention, unlike the conventional battery management system in order to solve the above problems, even if a problem occurs in the master BMS can operate without stopping the system, the stability is improved and the accuracy and speed compared to the conventional system smart slave is improved It is to provide a battery management system and a battery management method thereof.

In accordance with another aspect of the present invention, there is provided a battery management system for controlling a battery system in which a plurality of battery packs each configured by electrically connecting a plurality of battery cells are electrically connected to each other. Each of the plurality of battery packs measures and calculates data on electrical characteristic values of battery packs managed by the battery packs in real time, and communicates with each other to exchange their measured and calculated data in real time, and to store the data therein. And a smart slave BMS for monitoring the status of each other in real time by updating, wherein each of the plurality of smart slave BMSs has a structure configured to be capable of performing both a master function and a slave function. By switching to do one, One of the number of smart slave BMSs is switched to a master mode smart slave BMS to perform the master function and the other smart slave BMSs are switched to a slave mode smart slave BMS to perform the slave function and the master mode smart slave BMS The controller receives the measured and calculated data from each of the slave mode smart slave BMSs, collects and processes the data, controls the battery management system, and the slave mode smart slave BMS or the master mode smart slave BMS, whose status is recognized as a fault, Separate from the battery management system, wherein the separated master mode smart slave BMS is switched to one of the other smart slave BMSs selected as a new master mode smart slave BMS. It is replaced.

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In addition, the measured and computed data may in particular comprise one or more of an SOC estimate and an SOH estimate. In addition, the measured and calculated data may further include one or more of current and voltage, temperature, and ambient temperature of the battery cell or battery pack.

In addition, the master function smart slave BMS is the power supply control for the drive load externally connected to the battery management system, the charge and discharge control of the battery cells, the smoothing control of the voltage between the battery cells, of the processed data according to the external request One or more of operations and outputs can be performed.

In addition, the communication may be a CAN communication.

In addition, according to another aspect of the present invention, a plurality of battery packs each configured by electrically connecting a plurality of battery cells are configured to be electrically connected to each other, and each of the plurality of battery packs has both a master function and a slave function. A battery management method for controlling a battery system comprising a smart slave BMS configured to be executable and switched to perform one of the master function and a slave function upon selection, the method comprising:
Each of the plurality of smart slave BMSs communicate with each other to check a connection state between the plurality of smart slave BMSs, and to measure and calculate data on electrical characteristics of battery packs managed by each of them in real time, Monitoring each other's status in real time by exchanging with each other in real time and storing and updating each inside;
Check whether a master mode smart slave BMS that performs the master function is selected, and if not, switch one of the plurality of smart slave BMSs to the master mode smart slave BMS to perform a master function; The other smart slave BMS switches to a slave mode smart slave BMS to perform a slave function;
The slave mode smart slave BMS or the master mode smart slave BMS identified as the fault state is released from the battery management system to release the fault state, wherein the master mode smart slave BMS is disconnected; If one of the other smart slave BMS is selected to switch to a new master mode smart slave BMS to perform a master function;
The master mode smart slave BMS collecting and processing the measured and calculated data from each of the slave mode smart slave BMSs and controlling the battery management system.

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At this time, the master function smart slave BMS checks the voltage level of at least one of the remaining smart slave BMS in real time based on the measured and calculated data, and if the voltage level is below a predetermined reference range, the corresponding battery cell Is initially charged until it is within the above range, and when the voltage level is within a predetermined reference range, an electrical connection to an externally connected driving load of the battery management system may be initiated.

The slave mode smart slave BMS or the master mode smart slave BMS identified as the fault state is released from the battery management system to release the fault state, but the master mode smart slave BMS is disconnected. If one of the remaining other smart slave BMS is selected to switch to a new master mode smart slave BMS to perform a master function, by adding a new smart slave BMS to the battery management system to electrically connect The further other smart slave BMS selecting the one may further include the new smart slave BMS.

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Unlike the conventional system, the smart slave BMS system according to the present invention is greatly improved in stability and is very advantageous because it is operated by being replaced with another BMS without stopping the system even when a problem occurs in the master BMS. In addition, the smart slave BMS system according to the present invention, each smart slave BMS independently calculates each other's state data as well as the estimated state of the state of charge (SOC) and health state (SOH) of the battery independently and exchange and store and update them with each other. The master mode smart slave BMS only needs to collect and reconstruct these estimates in real time, which greatly improves precision and speed compared to conventional systems.

1A and 1B are schematic views showing the structure of a conventional battery pack system, respectively.
2 is a diagram schematically illustrating a structure of a smart slave BMS according to an embodiment of the present invention.
3 is a diagram schematically illustrating a structure of a smart slave BMS system 100 according to an embodiment of the present invention, in which a plurality of smart slave BMSs of FIG. 2 are connected to each other.
4 is a flowchart illustrating the operation of the smart slave BMS system according to the present invention.

First, as used herein, the term "fault" is used to encompass not only a failure of a battery cell or a BMS, but also disconnection, short circuit, and the like of these connection lines.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a plurality of so-called smart slave BMSs having a distributed structure in which a master BMS function is assigned to a slave BMS. This smart slave BMS is configured so that each board can also perform a master function.

According to the present invention, each of these smart slave BMSs are electrically connected to the respective battery packs, while communicating with each other, exchanging their own state data and estimated data calculated based on the same in real time, and communicating with each other in real time. The data of the BMS is stored and updated in each. One of these smart slave BMSs is arbitrarily selected to function as a master, and the smart slave BMSs (hereinafter referred to as "master mode smart slave BMSs") selected to function as masters receive data from the remaining smart slave BMSs and collect them. Based on this, the overall system is controlled.

Thus, in the present invention, when a smart slave BMS is in a fault state, it is recognized in real time and immediate action is possible. In particular, even when the master mode smart slave BMS that is currently functioning as a master becomes faulty, other smart slave BMSs can recognize it in real time as described above. By selecting it as a BMS and continuing to operate the system, it can be operated stably without interruption of the system. Therefore, when a problem occurs in the master BMS as in the prior art, it is very advantageous because the situation in which the entire system has to be stopped can be basically excluded.

In addition, according to the smart slave BMS according to the present invention, each smart slave BMS is a state data of each other (e.g., measurement of electrical characteristics of current and voltage, current and voltage of the battery pack, voltage and temperature of each battery cell and peripheral Sensing data such as temperature measurement) as well as estimates of the state of charge (SOC) and state of health (SOH) of the battery independently and in real time do. Thus, the master mode smart slave BMS only needs to collect and reconstruct these estimates in real time, thus greatly improving precision and speed compared to conventional systems.

The present invention as described above will now be described in detail with reference to the accompanying drawings.

2 illustrates components mounted on a board of a smart slave BMS 110 according to an embodiment of the present invention, and FIG. 3 is a schematic diagram of a smart slave BMS system 100 according to an embodiment of the present invention.

2 and 3, the smart slave BMS 110 according to the present invention is electrically connected to each battery pack 130 configured by stacking a plurality of battery cells 140 electrically connected to each other. The plurality of smart slave BMSs 100 are connected to each other as shown in FIG. 3 to form the entire smart slave BMS system 100.

As shown in FIG. 2, according to the present embodiment, the smart slave BMS 110 generally includes a sensing unit 112, a microcontroller unit (MCU) 111, a power supply unit 119, a storage unit 114, and a communication unit. Reference numeral 113 may include an interface unit 118, a protection circuit unit 117, and a mode control unit 115.

The sensing unit 112 transmits the sensing data obtained by measuring the current and voltage of the battery pack, the voltage and temperature of each battery cell, and the ambient temperature to the MCU 111. To this end, the sensing unit 112 may include a conventional analog-to-digital converter (ADC) for converting the measured analog data into digital data.

The sensor unit 170 may be connected to the sensing unit 112 including a current sensor measuring the output current of the battery pack and outputting the measured current to the sensing unit 112. In addition, as an embodiment, although not shown in FIG. 2, a cooling fan for cooling the generated heat of the battery pack based on a control signal output from the MCU 111 may be separately connected to the interface unit 118 from the outside.

In addition, the MCU 111 performs an operation based on the sensing data transmitted from the sensing unit 112 to perform a state of charge (“SOC”) and a state of health (“SOH”) of a battery. ), And generate and process information that informs the battery status and then provide it to the outside. As will be explained later, the SOC and SOH estimates thus provided are collected and the charge and discharge of the battery cell is controlled based on this.

In addition, as shown in FIG. 3, each smart slave BMS 110 is electrically connected to each other and exchanges and monitors various data including sensing data and SOC and SOH estimates. That is, as described above, each smart slave BMS 110 prepares in real time sensing data regarding its state, and calculates and extracts SOC and SOH estimates in real time from its MCU 111. In addition, the communication unit 113 of each smart slave BMS 110 exchanges each other by transmitting its various data to the other smart slave BMS 100 through the interface unit 118 and at the same time receiving their various data. The storage 140 of each smart slave BMS 110 stores and updates all data of the smart slave BMS 100 different from itself with the ID of the corresponding smart slave BMS 100. In the present invention, the storage unit 140 may be a conventional volatile or nonvolatile memory.

In addition, in the present invention, one of the plurality of smart slave BMS 110 is automatically selected by the mode controller 115 to perform a random master function, and thus the selected master mode smart slave BMS 110 is the remaining smart slave BMSs. The entire system is collectively controlled based on the general data received from the 110. In addition, as an embodiment of the present invention, a user may forcibly intervene through a switching element (for example, a dip switch) connected to the outside to manually select any master mode smart slave BMS 110.

By this. The remaining smart slave BMSs 110 are sensing data (for example, electrical characteristics of current and voltage, current and voltage of the battery pack, voltage and temperature of each battery cell, and ambient temperature) and SOC and SOH calculated based on the same. All data such as estimated values are exchanged, stored, and updated with each other, and transmitted to the selected master mode smart slave BMS 100 in real time.

In addition, the master mode smart slave BMS 110 performs power supply control, charge / discharge control, and smoothing voltage between cells based on the data transmitted from the remaining smart slave BMSs 110. It performs the function of controlling the whole system such as control. Although not shown in FIG. 2, as an embodiment, each smart slave BMS 110 of the present invention may further include a cell balancing configured with a conventional electric circuit for the voltage smoothing operation.

In addition, as an embodiment of the present invention, the master mode smart slave BMS 100 arbitrarily processes data transmitted from the remaining smart slave BMSs 100 in response to an external request, so that the master mode smart slave BMS 100 Average value, standard deviation, maximum value / minimum value, number, statistical value, etc.) may be output to an externally connected upper controller (not shown) or displayed on a display element.

In addition, the communication unit 113 of the smart slave BMS 110 communicates with an external device and the communication between the smart slave BMSs 110 through the interface unit 118 (that is, the smart slave BMS 110-smart). Communication of the slave BMS 110, communication of the smart slave BMS 110 to the master mode smart slave BMS 110).

In other words. The communication unit 113 of each smart slave BMS 110 transmits and receives each other's data with other smart slave BMSs 110. And, in the case of the communication unit 113 of the master mode smart slave BMS 110 selected as the master, while receiving all the data from the communication unit 113 of the remaining smart slave BMS 110, from the own MCU 111 Commands to the remaining smart slave BMSs 110 are transmitted to the remaining smart slave BMSs 110.

In addition, the communication unit 113 is located between the battery and the driving load (for example, the electric motor driving device) through the interface unit 118 to relay the electrical connection (Powr Relay Assembly: PRA) main relay (shown) May not be used). In addition, the communication unit 113 may use conventional RS232 / RS485 communication and / or controller area network (CAN) communication as an embodiment.

In addition, the protection circuit unit 117 shuts down the circuit when an overcharge, overdischarge, overcurrent or short circuit condition of the battery is detected, thereby preventing failure or fault of the battery cell. For example, the protection circuit unit 117 may include conventional over voltage protection (OVP), under voltage protection (UVP), over temperature protection (OTP), over current protection (OCP), and short circuit protection according to a voltage state of a battery. ), Etc. can be performed.

4 is a flowchart illustrating the operation of the smart slave BMS system 100 according to the present invention as described above.

Referring to FIG. 4, first, when the smart slave BMS system 100 is booted, each smart slave BMS 110 checks a connection state between mutually adjacent smart slave BMSs 110 and performs a real-time measurement as described above. The sensed data regarding its own state and the SOC and SOH estimates calculated based on the state thereof are interchanged with other smart slave BMSs 100 and stored and updated (S410).

At this time, whether or not a master mode smart slave BMS 110 is selected to perform a master function (S420), a failure of a battery cell or BMS from any smart slave BMS 110, disconnection or short circuit of a connection line, or the like. Check whether each fault is recognized (S440).

If the master mode smart slave BMS 110 is not selected (S420), one of the smart slave BMSs 110 is selected as the master mode smart slave BMS 110 (S430). This selection may in one embodiment be programmed based on the ID sequence number of the smart slave BMS 110 or may be programmed to be performed randomly. In another embodiment, as described above, the user may forcibly intervene in any master mode smart slave. It is also possible to manually select the BMS 110.

Here, each smart slave BMS 110 is a user or a higher level information (eg, ID or location information) of the faulted smart slave BMS 110 when a fault is recognized from any smart slave BMS 110 (S440). Output or display to the controller or the like so that immediate actions can be taken (S445). This measure separates the faulty smart slave BMS 110 and the battery pack 130 from the smart slave BMS system 100 in one embodiment of the present invention and replaces the existing smart slave BMS 110 with the existing or new smart slave BMS 110 and Electrical connection by replacing the battery pack 130, and if the faulty smart slave BMS 110 was a master mode smart slave BMS 110, the other smart And selecting one slave BMS 110 as the master mode smart slave BMS 110 to cause this new master mode smart slave BMS 110 to perform a master function. Therefore, in the present invention, the recognition and revocation of such a fault are applied both to the general smart slave BMS 110 as well as to the fault generation of the master mode smart slave BMS 110.

In addition, the master mode smart slave BMS 110 receives data including its state data and SOC and SOH estimates from the remaining smart slave BMS 110, and performs system control and arithmetic functions based on the data. Can be output or displayed as (S450).

In addition, the master mode smart slave BMS 110 checks the voltage level of the smart slave BMS 110 from the received data in real time prior to the electrical connection (S470) to the driving load (eg, the electric motor driving device) (S460). When the predetermined reference voltage range is not reached, current congestion can be prevented by initially precharging to the reference voltage range in a conventional manner (S465). When all battery packs have a predetermined reference voltage range (S460), the master mode smart slave BMS 110 turns on the main relay to electrically connect the entire system to the driving load (S470).

As described above, according to the present invention, each of the smart slave BMS checks the connection state between each other and exchanges its own state data and estimated value data calculated based on this in real time to exchange data of itself and other smart slave BMSs, respectively. In particular, one of these smart slave BMSs is arbitrarily selected as a master mode smart slave BMS, receives data from the remaining smart slave BMSs, collects data, and collectively controls the entire system based thereon.

Thus, in the present invention, when a smart slave BMS is in a fault state, it is not only recognized in real time and can take immediate action, but especially when the master mode smart slave BMS is in a fault state, it is recognized in real time and is transferred to another smart slave BMS. Immediate replacement allows for reliable operation without any system disruption. Therefore, when a problem occurs in the master BMS as in the prior art, it is very advantageous because the situation where the entire system was forced to be stopped can be basically excluded.

In addition, according to the smart slave BMS according to the present invention, each smart slave BMS independently calculates and exchanges the estimated values of the state of charge (SOC) and the state of health (SOH) of the battery as well as each other's state data. And storage updates, the master mode smart slave BMS only needs to collect and reconstruct these estimates in real time, greatly improving precision and speed compared to conventional systems.

The above-described contents of the present invention are disclosed for purposes of illustration, and any person skilled in the art may make various modifications, changes, and additions within the spirit and scope of the present invention. Etc. shall be regarded as belonging to the claims.

100: smart slave BMS system 110: smart slave BMS
111: MCU 112: sensing unit
113: communication unit 114: storage unit
115: mode control unit 117: protection circuit unit
119: power supply unit 130: battery pack
140: battery cell 170: sensor unit

Claims (12)

A battery management system for controlling a battery system in which a plurality of battery packs configured by electrically connecting a plurality of battery cells to each other are electrically connected to each other.
Each of the plurality of battery packs measures and calculates data on electrical characteristic values of a battery pack managed by the battery pack in real time, and communicates with each other to exchange their measured and calculated data in real time, and to store the data therein. And a smart slave BMS that monitors each other's status in real time by updating,
Each of the plurality of smart slave BMSs has a structure configured to perform both a master function and a slave function, and is switched to perform one of the master function and the slave function according to a selection, so that one of the plurality of smart slave BMSs is a master. Switch to mode smart slave BMS to perform the master function and the other smart slave BMSs to switch to slave mode smart slave BMS to perform the slave function, and the master mode smart slave BMS Receives and collects measured and calculated data and controls the battery management system,
The slave mode smart slave BMS or master mode smart slave BMS whose status is recognized as fault is disconnected from the battery management system, wherein the separated master mode smart slave BMS is one of the other other smart slave BMSs. Battery management system, characterized in that replaced by being selected and switched to BMS. delete delete The method of claim 1,
And the measured and calculated data comprises at least one of an SOC estimate and an SOH estimate. The method of claim 4, wherein
The measured and calculated data further comprises at least one of the current and voltage, temperature and ambient temperature of the battery cell or battery pack. The method of claim 1,
The master mode smart slave BMS performs power supply control for a driving load externally connected to the battery management system, charge / discharge control of the battery cells, smoothing control of voltages between the battery cells, and operation of the processed data according to an external request. And at least one of an output. The method of claim 1,
The communication is a battery management system, characterized in that the CAN communication. A plurality of battery packs each configured by electrically connecting a plurality of battery cells are configured to be electrically connected to each other, each of the plurality of battery packs is configured to perform both a master function and a slave function, the master function according to the selection A battery management method for controlling a battery system including a smart slave BMS switched to perform one of slave functions,
Each of the plurality of smart slave BMSs communicate with each other to check a connection state between the plurality of smart slave BMSs, and to measure and calculate data on electrical characteristic values of battery packs managed by each of them in real time, and to measure and calculate their own measured and calculated data in real time. Monitoring the status of each other in real time by exchanging with each other and storing and updating each inside;
Check whether the master mode smart slave BMS that performs the master function is selected, and if not selected, switch one of the plurality of smart slave BMSs to the master mode smart slave BMS to perform the master function and the other The smart slave BMS switches to a slave mode smart slave BMS to perform a slave function;
When the slave mode smart slave BMS or the master mode smart slave BMS identified as the fault state is released from the battery management system to terminate the fault state, but the master mode smart slave BMS is disconnected, Selecting one of the other smart slave BMSs and switching to a new master mode smart slave BMS to perform a master function;
And the master mode smart slave BMS collects and processes the measured and calculated data from each of the slave mode smart slave BMSs and controls the battery management system. The method of claim 8,
The master mode smart slave BMS
Check the voltage level of the slave mode smart slave BMS in real time based on the measured and calculated data;
If the voltage level is below the range of the predetermined reference, the battery cell is initially charged until it reaches the range,
And initiating an electrical connection to an externally connected drive load of the battery management system when the voltage level is within a predetermined reference range. The method of claim 8,
The slave mode smart slave BMS or the master mode smart slave BMS identified as the fault state is released from the battery management system to release the fault state, but the master mode smart slave BMS is disconnected. Selecting one of the other smart slave BMSs and switching to a new master mode smart slave BMS to perform a master function
Injecting a new smart slave BMS to the battery management system further comprising the step of electrically connecting, wherein the remaining other smart slave BMS to select the one battery characterized in that it comprises the new smart slave BMS How to manage. delete delete

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