Battery management apparatus and method for setting can baud rate

Abstract

To provide a battery management apparatus and a method thereof for automatically setting a baud rate of an external device with the battery management apparatus and automatically setting a baud rate according to the external device when one type of battery pack is used in multiple models of external devices such as e.g., laborious extra-orbital vehicle (LEV), electrical vehicle (xEV), or energy storage system (ESS).SOLUTION: A battery management apparatus includes: an interface unit configured to perform Controller Area Network (CAN) communication with an external device through a CAN bus line; and a Micro Controller Unit (MCU) configured to set a CAN baud rate based on whether an error is detected in a CAN message frame received from the external device through the interface unit. Therefore, it is not necessary to prepare a separate device for setting the baud rate and operator error can be prevented.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present disclosure relates to a battery management device and method for setting a CAN (Controller Area Network) communication speed.

Background Art

[0002] Generally, a secondary battery (battery) is different from a primary battery that cannot be charged in that it can be charged and discharged. In the case of a low-capacity battery in which one battery cell is packaged in a pack form, such a battery is used in portable small electronic devices such as mobile phones and video cameras. In the case of a high-capacity battery in which dozens of battery cells are connected, such a battery is used as a power source for motor drive such as electric bicycles, electric scooters, hybrid vehicles, and electric vehicles.

[0003] When a secondary battery is used in an external device (for example, LEV, xEV, or ESS), the secondary battery and the external device transmit and receive data using CAN communication.

[0004] On the other hand, when one type of secondary battery is used in external devices of various models (for example, LEV, xEV, or ESS) and the CAN communication speeds of the respective external devices are different, in order to make the communication speed of the secondary battery compatible, there is a method of individually setting the communication speed through external communication or providing communication speed information preset in a battery management system (BMS) using an external connector.

[0005] However, the method of individually setting the communication speed through the external communication of the battery pack before connecting the CAN communication line of the BMS to the CAN bus of the external device requires a separate setting device (for example, a PC + GUI program or a device for transmitting separate communication data) for setting the communication speed, and there is a problem that it is erroneously set due to an operator's mistake.

[0006] In addition, a method of receiving a signal from an external connector connected to a battery pack by a BMS and operating at a pre-set communication speed requires separate hardware for receiving an external signal and has a problem of being erroneously set due to an operator's mistake.

[0007] The information disclosed in the above items of the background art of the present invention is only for deepening the understanding of the background of the present invention, and thus may include information that does not constitute related art.

Summary of the Invention

Problems to be Solved by the Invention

[0008] An object of the present invention is to provide a battery management device and a method therefor for setting a CAN communication speed such that when using one type of battery pack in external devices of a plurality of models (for example, a low-speed electric vehicle (LEV), an electric vehicle (xEV), an energy storage system (ESS), etc.), the CAN communication speed can be automatically set according to the external device.

[0009] However, the technical problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can also be clearly understood by those skilled in the art from the description of the invention described below.

Means for Solving the Problems

[0010] A battery management device according to an embodiment of the present invention for solving the above technical problems is characterized in that it automatically sets the CAN communication speed based on whether an error is detected in a CAN message frame received from an external device through a CAN bus line.

Effects of the Invention

[0011] According to the present invention, when using one type of battery pack in a plurality of models of external devices (e.g., LEV, xEV, ESS, etc.), the battery management device can automatically detect the communication speed of the external device and automatically set the communication speed suitable for the external device. Therefore, there is no need to prepare a separate device for setting the communication speed, and it is effective in preventing operator errors.

[0012] However, the effects that can be obtained through the present invention are not limited to those described above, and other technical effects not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

Brief Description of the Drawings

[0013] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further understand the technical idea of the present invention together with the detailed description of the invention to be described later. Therefore, the present invention should not be construed as being limited only to the matters described in such drawings.

Figure 1

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Figure 4

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Figure 8

Best Mode for Carrying Out the Invention

[0014] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and the claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor should conform to the principle that he can appropriately define the concept of the terms in order to explain his own invention in the best way, and should be construed in a meaning and concept that conforms to the technical idea of the present invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only some of the most preferred embodiments of the present invention, and do not represent all of the technical ideas of the present invention. It should be understood that there may be various equivalents and modifications that can replace them at the time of this application. Also, when used in this specification, "comprise", "include" and / or "comprising", "including" are used to specify the presence of the recited shape, number, step, operation, member, element and / or group thereof, and do not exclude the presence or addition of one or more other shapes, numbers, operations, members, elements and / or groups. Also, when describing the embodiments of the present invention, "can be" and "can be" can include "one or more embodiments of the present invention".

[0015] Also, for the purpose of assisting in the understanding of the invention, the attached drawings are not shown at actual scale, and the dimensions of some components may be exaggerated. Also, the same reference numerals may be assigned to the same components in different embodiments.

[0016] The reference that two comparison targets are "identical" means "substantially identical". Therefore, substantial identity can include cases having a deviation regarded as a low level in the art, for example, a deviation within 5%. Also, the fact that a parameter in a predetermined region is uniform may mean that it is uniform from an average point of view.

[0017] Although the terms first, second, etc. may be used to describe various components, it goes without saying that these components are not limited by these terms. These terms are merely used to distinguish one component from another, and it goes without saying that, unless otherwise stated, the first component may be the second component.

[0018] Throughout the specification, unless otherwise stated, each component may be singular or plural.

[0019] The statement that any configuration is disposed "above (or below)" a component or "on (or under)" a component means not only that any configuration is disposed in contact with the upper (or lower) surface of the component, but also that other configurations may be interposed between the component and any configuration disposed on (or under) the component.

[0020] Also, when a component is described as "connected", "coupled" or "joined" to another component, it should be understood that the components may be directly connected or joined to each other, or that other components may be "interposed" between the components, or that each component may be "connected", "coupled" or "joined" to another component through other components. Also, when a part is said to be electrically coupled to another part, this includes not only the case where they are directly connected, but also the case where other elements are interposed therebetween.

[0021] Throughout the specification, "A and / or B" means A, B, or A and B, unless otherwise stated. That is, "and / or" includes all combinations or any combination of the listed multiple items. "C to D" means C or more and D or less, unless otherwise stated.

[0022] FIG. 1 illustrates a CAN communication speed setting system for a battery pack according to an embodiment of the present invention. FIG. 2 illustrates a circuit of a battery pack according to an embodiment of the present invention. FIG. 3 illustrates a CAN bus line connecting an external device and a battery pack according to an embodiment of the present invention. FIG. 4 schematically illustrates a configuration of a battery management device according to an embodiment of the present invention. FIG. 5 illustrates an example of a CAN frame. FIG. 6 illustrates an example of an interrupt generation time interval according to an embodiment of the present invention.

[0023] Referring to FIGS. 1 and 2, a communication speed setting system for a battery pack according to an embodiment of the present invention may include an external device 10 and a battery pack 100.

[0024] The external device 10 may have a structure that is electrically connected through a positive connection terminal (P(+)) and a negative connection terminal (P(−)) of the battery pack 100.

[0025] The external device 10 may be a load that receives power supply from the battery pack 100, or may be a charging device that supplies power to the battery pack 100 to charge a plurality of battery modules 110.

[0026] When the external device 10 is a load, the battery pack 100 may discharge by operating as a power source that supplies power to the load. The external device 10 operating as a load may be, for example, an electronic device, a moving means, or an energy storage system (ESS), and the moving means may be, for example, an electric vehicle, a hybrid vehicle, or smart mobility.

[0027] Also, while the external device 10 is connected to the battery pack 100, it may transmit a predetermined communication signal at a predetermined period. In this case, the external device 10 and the battery pack 100 can perform transmission and reception of signals (data) through CAN communication. That is, an upper controller (not shown) of the external device 10 (for example, an electric system, an electric vehicle) (for example, a VCU (Vehicle Control Unit), an ECU (Electronic Control Unit), etc.) and the battery pack 100 may be connected to a CAN bus line, and data may be transmitted and received through the CAN bus line illustrated in FIG. 3.

[0028] The upper controller of the external device 10 can transmit a CAN message frame to the battery pack 100 through the CAN bus line. Also, the upper controller of the external device 10 can receive a CAN message frame from the battery pack 100 through the CAN bus line.

[0029] The battery pack 100 is connected to the external device 10 through a connector 140, and the power terminals of the external device 10 may be connected to the first pack terminal (P+) and the second pack terminal (P-) of the connector 140.

[0030] The battery pack 100 may include a first pack terminal (P+) and a second pack terminal (P-) corresponding to a plurality of battery cells, and may be connected to the external device 10 through the first pack terminal (P+) and the second pack terminal (P-).

[0031] The battery pack 100 is provided to be installable in the external device 10 (for example, an electric vehicle), and may include at least one battery module 110, a switch 130, and a battery management device (BMS) 120. Needless to say, in various embodiments, the battery pack 100 can further include other components.

[0032] The battery module 110 may include a plurality of battery cells and a module housing. The battery module 110 may include a plurality of cells connected in series or in parallel with each other. The battery module 110 may be connected in series or in parallel with each other.

[0033] The battery cells may be housed inside the module housing in a stacked form. The battery cells may include a positive electrode lead and a negative electrode lead. Depending on the form of the battery, circular, rectangular, or pouch-type battery cells may be used.

[0034] In the battery pack 100, one module may be composed of a single stacked cell stack instead of the battery module 110. The cell stack may be housed in the accommodation space of the pack housing or in an accommodation space partitioned by a frame, a partition wall, etc.

[0035] The battery cells generate a large amount of heat during charging / discharging. The generated heat is accumulated in the battery cells and accelerates the degradation of the battery cells. Therefore, the battery pack 100 can further include a cooling member to suppress the degradation of the battery cells. The cooling member is provided at the lower part of the accommodation space where the battery cells are provided, but is not limited thereto and may also be provided at the upper part or the side surface by the battery pack 100.

[0036] The exhaust gas inside the battery cells generated under abnormal operating conditions, also known as thermal runaway or thermal events of the battery cells, can be discharged to the outside of the battery cells. The battery pack 100 or the battery module 110 can be equipped with an exhaust port or the like for discharging the exhaust gas to suppress damage to the battery pack 100 or the module.

[0037] The switch 130 is connected between the battery module 110 and at least one of the first and second pack terminals (P+, P−) to be able to cut off / allow the electrical connection between the battery module 110 and the external device 10.

[0038] The switch 130 can be installed in the current path for charging and discharging of the battery module 110.

[0039] The switch 130 can control the electrical connection between the battery pack 100 and the external device 10. When the switch 130 is turned on, the battery pack 100 and the external device 10 can be electrically connected and charging or discharging can be performed. When the switch 130 is turned off, the battery pack 100 and the external device 10 can be electrically separated. That is, when the switch 130 is turned on, power can be supplied from the battery module 110 to the external device 10 or power can be supplied from the external device 10 to the battery module 110. While the switch 130 is turned off, the charging and discharging of the battery module 110 can be interrupted. At this time, the switch 130 can be turned on or off under the control of the battery management device 120.

[0040] Such a switch 130 may be realized as a mechanical relay (contact) turned on / off by the magnetic force of a coil, a semiconductor switch such as a MOSFET (Metal Oxide Semiconductor Field Effect transistor), or the like.

[0041] The battery management device 120 diagnoses the presence or absence of an abnormality in the battery pack 100 based on battery state data representing the state of the battery module 110. When there is no abnormality in the battery pack 100, it turns on the switch 130 to receive a CAN message frame from the external device 10 through the CAN bus line, and can set the CAN communication speed based on whether an error is detected in the received CAN message frame. At this time, if no error is detected in the CAN message frame, the battery management device 120 can determine that the CAN communication speed is the same as that of the external device 10. If an error is detected in the CAN message frame, the battery management device 120 determines that the CAN communication speed is not the same as that of the external device 10 and can change the preset CAN communication speed to a different CAN communication speed.

[0042] Such a battery management device 120 can include a memory 122, a detection unit 124, an interface unit 126, and an MCU (Micro Controller Unit, 128).

[0043] The memory 122 is configured to store data related to the operation of the battery management device 120. In particular, the memory 122 may store a program (application or applet) that enables the CAN communication speed to be set based on the presence or absence of error detection of the CAN message frame received from the external device 10, and the stored information can be selectively retrieved by the processor as needed. That is, the memory 122 stores various types of data generated during the operation system for driving the battery management device 120 and the execution process of the program (application or applet). Also, the memory 122 stores the configurable CAN communication speeds. Here, the configurable CAN communication speeds may include all the communication speeds of the available external devices 10, or may include all the commonly set CAN communication speeds. For example, the configurable CAN communication speeds can include 100 kbps, 125 kbps, 250 kbps, 500 kbps, 1 Mbps, etc. Therefore, the memory 122 may store a communication speed table with a plurality of different CAN communication speeds set therein.

[0044] The memory 122 is a general term for a non-volatile storage device that continues to maintain the stored information even when power is not supplied and a volatile storage device that requires power to maintain the stored information. Also, the memory 122 can perform the function of temporarily or permanently storing the data processed by the processor. Here, the memory 122 can include a magnetic storage media or a flash storage media in addition to the volatile storage device that requires power to maintain the stored information, but the scope of the present invention is not limited thereto.

[0045] The detection unit 124 can sense the state (such as voltage, current, temperature, etc.) of the battery module 110 and detect battery state data representing the state of the battery. The detection unit 124 can detect the voltage of each cell or each battery module 110 constituting the battery. The detection unit 124 can also detect the current flowing through the battery module 110 or each battery module 110 constituting the battery pack 100. The detection unit 124 can also detect the ambient temperature at at least one point of the battery.

[0046] Such a detection unit 124 may include a voltage sensor, a current sensor, a temperature sensor, etc.

[0047] The detection unit 124 can be configured to periodically output battery state data representing the voltage and current of the battery module 110, ambient temperature, etc., detected at regular intervals (for example, per unit time) to the MCU 128.

[0048] The interface unit 126 enables CAN communication with the external device 10 through the CAN bus line.

[0049] The interface unit 126 can be CAN communication between the MCU 128 and a host controller (not shown) of the external device 10 (for example, an electric system, an electric vehicle) (for example, VCU, ECU, etc.).

[0050] When the external device 10 is connected to the connector 140 of the battery pack 100, the interface unit 126 can enable CAN communication between the battery management device 120 and the external device 10. At this time, the external device 10 and the battery pack 100 are connected to the CAN bus line and can transmit and receive data through the CAN bus line.

[0051] Therefore, the interface unit 126 can transmit or receive CAN message frames through the CAN bus line. That is, the interface unit 126 can transmit the CAN message frames received from the CAN bus line to the MCU 128, or transmit the CAN message frames representing information about the battery pack 100 or battery management information to the CAN bus line under the control of the MCU 128.

[0052] The MCU 128 can sense the CAN message frames received from the external device 10 through the interface unit 126. At this time, the MCU 128 can determine the presence or absence of the CAN message frame based on the number of bits of the bit signal received through the interface unit 126. That is, when the received bit signal is a frame according to the CAN communication protocol, the MCU 128 can determine it as a CAN message frame.

[0053] A CAN frame for CAN communication can have a structure as shown in FIG. 5. As shown in FIG. 5, the CAN frame includes a SOF (Start Of Frame) that indicates the start of the frame, an Arbitration ID Field for inserting an arbitration ID for data priority arbitration, an RTR (Remote Transmission Request) bit for requesting data transmission of a specific ID (Identification), a Control Field for transmitting control signals, a Data Field on which data having a predetermined data length is loaded, a CRC (Cyclic Redundancy Check) field composed of a CRC Sequence and a CRC Delimiter for error detection, an ACK (Acknowledgement) field composed of an ACK slot and an ACK Delimiter for indicating the accuracy of data reception, and an EOF (End of Frame). The Control Field generally includes an IDE (Identifier Extension) for indicating whether the length of the arbitration ID is standard (11 bits) or extended (29 bits) and a DLC (Data Length Code) representing the data length.

[0054] Therefore, when the bit signal fed back has a structure as shown in FIG. 5, the MCU128 can determine that the corresponding bit signal is a CAN frame.

[0055] The MCU128 can set the CAN communication speed based on the presence or absence of error detection in the CAN message frame received from the external device 10 through the interface unit 126. At this time, the MCU128 can set the CAN communication speed through error detection of the CAN message frame or set the CAN communication speed based on the pulse width of the CAN message frame. The communication speed set by the MCU128 can be the same as the CAN communication speed of the external device 10.

[0056] Hereinafter, a method for the MCU128 to set the CAN communication speed to be the same as that of the external device 10 will be specifically described.

[0057] First, a method for the MCU128 to set the CAN communication speed through error detection of the CAN message frame will be described.

[0058] When the battery management device 120 is woken up, the MCU128 initializes the CAN communication speed to the most recently used CAN communication speed, checks whether there is an error in the CAN message frame received from the external device 10 at the initialized CAN communication speed. When no error is detected, the initialized CAN communication speed is set as the final CAN communication speed. When an error is detected, it can be changed to a CAN communication speed that has not been used among the CAN communication speeds set in the communication speed table.

[0059] Specifically, when a signal for operating the external device 10 is input or a signal for turning on the battery pack 100 is input, the battery management device 120 can be woken up.

[0060] For example, when an electric vehicle is connected and the engine is started, the battery management device 120 can be woken up. Also, in the case of the battery pack 100 with an external switch 130, when the external switch 130 is turned on, the battery management device 120 can be woken up.

[0061] When the battery management device 120 is woken up, the MCU128 can initialize the CAN communication speed to the communication speed stored in the memory 122. Here, the communication speed stored in the memory 122 may mean the most recently used CAN communication speed.

[0062] When the CAN communication speed is initialized, the MCU 128 can diagnose whether there is an abnormality in the battery pack 100. At this time, the MCU 128 can diagnose whether there is an abnormality in the battery pack 100 based on the battery state data detected through the detector 124.

[0063] The MCU 128 receives the battery state data representing the state of the battery module 110 from the detector 124, and can diagnose whether there is an abnormality in the battery pack 100 based on the battery state data. That is, the MCU 128 can receive the state data (such as voltage, current, temperature, etc.) of the battery module 110 from the detector 124. After that, the MCU 128 can monitor and calculate the state (such as voltage, current, temperature, state of charge (SOC), state of health (SOH), etc.) of the battery module 110 based on the state data received from the detector 124. In addition, the MCU 128 can also execute control functions (such as temperature control, balancing control, charge and discharge control, etc.), protection functions (such as over-discharge, over-charge, over-current prevention, short circuit, fire extinguishing function, etc.), etc. based on the state monitoring result.

[0064] The MCU 128 controls the battery to operate stably through the diagnosis of the battery state. When the diagnosis result determines that the operation of the battery is no longer possible, the MCU 128 controls the battery pack 100 not to operate any more, and can prevent various problems that may be caused by the battery in advance. That is, the MCU 128 can diagnose the abnormalities that may occur in the battery pack 100 based on the battery state data.

[0065] The MCU 128 can control the on or off state of the switch 130 based on the diagnostic result of the battery pack 100. That is, when it is diagnosed that no abnormality has occurred in the battery pack 100, the MCU 128 can turn on the switch 130. When it is diagnosed that an abnormality has occurred in the battery pack 100, the MCU 128 can turn off the switch 130. For example, when it is diagnosed that the voltage, current, temperature are above the threshold value or a sensor failure has occurred, the MCU 128 can prevent the battery pack 100 from being used by not turning on the switch 130.

[0066] When the switch 130 is turned on, the MCU 128 can receive a CAN message frame from the external device 10 through the interface unit 126. That is, when the switch 130 is turned on, the external device 10 and the battery module 110 are connected, and the external device 10 can transmit a CAN message frame to the MCU 128 through the CAN bus line.

[0067] For example, when the switch 130 is turned on, components constituting the external device 10 that operate by receiving power from the battery pack 100 (for example, in the case of an electric vehicle, other components sharing the CAN bus such as an instrument panel and a motor controller) receive power supply and are woken up. When the components constituting the external device 10 are woken up, the external device 10 can transmit a CAN message frame to the MCU 128 through the CAN bus line. Also, in the case of a charger, since the charger is receiving the application of ac power and is in a wake-up state, the charger can transmit a CAN message frame to the MCU 128 through the CAN bus line.

[0068] On the other hand, the CAN message frame may not be transmitted to the battery management device 120 during the initially set communication speed setting time according to the type of the external device 10. In such a case, the MCU 128 can transmit the CAN message frame to the external device 10.

[0069] That is, if no CAN message frame is received from the external device 10 during a preset initial communication speed setting time, the MCU 128 can transmit a CAN message frame (for example, a CAN message frame for wake-up) to the external device 10 and can receive a response CAN message frame for that CAN message frame. For example, when the MCU 128 transmits a CAN message frame for wake-up to the external device 10, the external device 10 can transmit a response CAN message frame as a response to the wake-up.

[0070] If the CAN communication speeds of the battery management device 120 and the external device 10 are set to be the same, the MCU 128 will receive a normal CAN message frame. If the CAN communication speeds of the battery management device 120 and the external device 10 are different, an error will be detected in the CAN message frame.

[0071] Thereby, the MCU 128 can inspect whether there is an error in the CAN message frame received from the external device 10. That is, the MCU 128 can analyze the CAN message frame to detect an error.

[0072] For example, the MCU 128 can detect bit errors, Stuff errors, Form errors, CRC (Cyclic Redundancy Check) errors, and acknowledgement bit errors. A bit error occurs when information transmitted from one node is not represented on the CAN bus. A Stuff error occurs when six consecutive bit values appear in the CAN protocol even though they should not in principle. A Form error occurs when bit values specified as 0 or 1 appear differently. A CRC error occurs when it is confirmed through CRC calculation for the CRC area of the received information that some bits have been changed. An acknowledgement bit error occurs when the control unit receives the received information without error and the acknowledgement bit having a bit value of 0 has a different value.

[0073] If no error is detected in the CAN message frame, the MCU 128 can set the initialized CAN communication speed to the final communication speed and save it in the memory 122. That is, if no error is detected in the CAN message frame, the MCU 128 can determine that the communication speed is the same as that of the external device 10 and set the initialized CAN communication speed to the final communication speed.

[0074] If an error is detected in the CAN message frame, the MCU 128 can use a counter (not shown) to count the number of detected errors, compare the number of errors with a preset threshold, and change the initialized CAN communication speed to a different CAN communication speed. That is, if the number of errors detected in the CAN message frame is equal to or greater than the threshold, the MCU 128 can determine that the communication speed is different from that of the external device 10 and automatically change the initialized CAN communication speed to a different CAN communication speed. Here, the threshold is an arbitrarily set number and can be set to vary depending on the number of CAN message frames on the CAN bus line.

[0075] When the number of detected errors is equal to or greater than the threshold, the MCU 128 changes the initialized CAN communication speed to a different CAN communication speed, determines whether there is an error in the CAN message frame received from the external device 10 at the changed CAN communication speed, and if no error is detected, can determine the changed CAN communication speed as the final communication speed and save it in the memory 122. At this time, the MCU 128 can select a CAN communication speed different from the initialized CAN communication speed from the CAN communication speeds in the communication speed table stored in the memory 122 and change to the selected CAN communication speed.

[0076] For example, if 100 kbps, 125 kbps, 250 kbps, 500 kbps, and 1 Mbps are set as the CAN communication speeds in the communication speed table and the initialized CAN communication speed is 125 kbps, the MCU 128 can change the communication speed to 250 kbps.

[0077] When the CAN communication speed is changed, the MCU 128 can receive a CAN message frame from the external device 10 at the changed CAN communication speed and check whether an error has occurred in the received CAN message frame.

[0078] If no error is detected in the CAN message frame received from the external device 10 at the changed CAN communication speed, the MCU 128 can determine the changed CAN communication speed as the final communication speed.

[0079] If an error is detected in the CAN message frame received from the external device 10 at the changed CAN communication speed, the MCU 128 can compare the number of detected errors with the threshold and change the changed communication speed to a different CAN communication speed again. At this time, the MCU 128 can select and change a CAN communication speed that has not been used from the communication speed table.

[0080] For example, 100kbps, 125kbps, 250kbps, 500kbps, and 1Mbps are set as the CAN communication speeds in the communication speed table. As a result of changing the initialized CAN communication speed from 125kbps to 250kbps, if the number of errors exceeds the threshold, the MCU128 can change the communication speed to 250kbps.

[0081] The MCU128 can obtain the CAN communication speed not used in the communication speed table until no error is detected in the CAN message frame, and continuously change the communication speed to the obtained CAN communication speed.

[0082] In this way, the MCU128 can select one of the CAN communication speeds stored in the memory 122 and continuously change it until no error is detected and a normal CAN message frame is received.

[0083] The MCU128 can save the CAN communication speed at which the communication is successful to the memory 122 (NVM).

[0084] Changing the CAN communication speed when a CAN error is sensed can only operate for a certain period of time after the wake-up of the battery management device 120 to actually detect a CAN communication error.

[0085] The MCU128 can transmit a test message at the changed CAN communication speed through the CAN bus line to the external device 10. If there is no error, the communication speed can be finally determined. At this time, the MCU128 checks whether an error occurs. If no error occurs, it finally determines the communication speed as the final communication speed, so as to enable smooth communication between the battery management device 120 and the external device 10. That is, the MCU128 changes the CAN communication speed of the battery pack 100 to match the CAN communication speed of the external device 10, thereby enabling smooth communication between the battery management device 120 and the external device 10.

[0086] Next, a method of changing the communication speed by using the pulse width of the CAN message frame will be described.

[0087] When the CAN RX pin is set to the external interrupt mode, the MCU128 calculates the interrupt occurrence time interval each time an interrupt occurs, calculates the communication speed based on the interrupt occurrence time interval within a preset fixed time, obtains the communication speed most similar to the calculated communication speed from the communication speed table, initializes it to the CAN communication speed, checks whether there is an error detection of the CAN message frame received from the external device 10 at the initialized CAN communication speed, and can set the initialized CAN communication speed to the final CAN communication speed when no error is detected.

[0088] Specifically, when the external device 10 is connected, the MCU128 can diagnose whether there is an abnormality in the battery pack 100. At this time, the MCU128 can diagnose whether there is an abnormality in the battery pack 100 based on the battery state data detected through the detection unit 124.

[0089] The MCU128 can control the on or off of the switch 130 according to the diagnosis result of the battery pack 100. That is, when it is diagnosed that an abnormality has occurred in the battery pack 100, the MCU128 can turn off the switch 130. When it is diagnosed that no abnormality has occurred in the battery pack 100, the MCU128 can turn on the switch 130.

[0090] When the switch 130 is turned on, the MCU128 can receive a CAN message frame from the external device 10 through the interface unit 126. That is, when the switch 130 is turned on, the external device 10 and the battery module 110 are connected, and the external device 10 can transmit a CAN message frame to the MCU128 through the CAN bus line.

[0091] At this time, if no CAN message frame is received from the external device 10 during the preset initial communication speed setting time, the MCU128 can transmit a CAN message frame (for example, a CAN message frame for wake-up) to the external device 10 and receive a response CAN message frame for that CAN message frame. For example, when the MCU128 transmits a CAN message frame for wake-up to the external device 10, the external device 10 can transmit a response CAN message frame as a response to the wake-up.

[0092] When a CAN message frame is received from the external device 10, the MCU128 can calculate the time interval at which the interrupt occurred each time an interrupt occurs. At this time, the interrupt can be set to occur at all rising edges and falling edges.

[0093] Therefore, the MCU128 can use the timer to calculate the time interval at which the interrupt occurs each time an interrupt occurs at the rising edge and the falling edge. At this time, the CAN RX Pin of the MCU128 can be set to the external interrupt mode. The CAN RX Pin of the MCU128 can be used in the CAN communication mode, the external interrupt mode, etc., but these cannot be used simultaneously. Therefore, when the CAN RX Pin of the MCU128 is set to the external interrupt mode, the time is calculated each time an interrupt occurs, and when the CAN communication speed is determined, the CAN RX Pin can be changed to the CAN communication mode.

[0094] After the interrupt occurrence time interval is calculated, the MCU128 can select the minimum time (tmin) among the interrupt occurrence time intervals for a preset fixed time as 1 bit time (time), and calculate the communication speed using the selected minimum time. At this time, the MCU128 can calculate the communication speed (baud rate) by calculating the reciprocal of the selected minimum time. That is, the MCU128 can calculate "1 / minimum time" as the communication speed.

[0095] For example, when an interruption occurs as shown in Fig. 6(a), since 1μm is the minimum time, the MCU128 can calculate 1Mbps (1 / 1μm = 1Mbps) as the communication speed.

[0096] When an interruption occurs as shown in Fig. 6(b), since 2μm is the minimum time, the MCU128 can calculate 500kbps (1 / 2μm = 500kbps) as the communication speed.

[0097] Once the communication speed is calculated, the MCU128 can initialize the CAN communication speed to the communication speed that is most similar to the calculated communication speed in the communication speed table stored in the memory 122.

[0098] The calculated communication speed may not be the exact communication speed due to measurement errors of the timer, etc. The commonly used CAN communication speeds such as 100kbps, 125kbps, 250kbps, 500kbps, 1Mbps, etc. are pre-stored in the memory 122. Therefore, the MCU128 can select the communication speed that is most similar to the calculated communication speed from the CAN communication speeds set in the communication speed table stored in the memory 122 as the CAN communication speed.

[0099] On the other hand, if the CAN communication speeds of the battery management device 120 and the external device 10 are set to be the same, the MCU128 will receive a normal CAN message frame. If the CAN communication speeds of the battery management device 120 and the external device 10 are different, an error will be detected in the CAN message frame.

[0100] Therefore, when the CAN communication speed is initialized, the MCU128 receives a CAN message frame from the external device 10 at the initialized CAN communication speed, checks whether an error occurs in the received CAN message frame, and if no error occurs, can determine the initialized communication speed as the final communication speed.

[0101] Specifically, the MCU 128 can inspect whether there is an error in the CAN message frame received from the external device 10. That is, the MCU 128 can analyze the CAN message frame to detect errors.

[0102] For example, the MCU 128 can sense bit errors, Stuff errors, Form errors, CRC (Cyclic redundancy check) errors, and acknowledgement bit errors.

[0103] If no error is detected in the CAN message frame received from the external device 10, the MCU 128 can finally determine the initialized CAN communication speed as the final communication speed.

[0104] When an error is detected in the CAN message frame received from the external device 10, the MCU 128 calculates the interrupt occurrence time interval again each time an interrupt occurs, re - selects the minimum time (tmin) among the interrupt occurrence time intervals within a preset fixed time as 1 bit time (time), recalculates the communication speed using the selected minimum time, and re - selects the communication speed most similar to the communication speed calculated in the communication speed table stored in the memory 122 to initialize the CAN communication speed.

[0105] In this way, the MCU 128 can continuously change the communication speed until an error is not detected and a normal CAN message frame is received.

[0106] The MCU 128 can store the communication speed at which the communication is successful in the memory 122 (NVM).

[0107] Here, the MCU 128 can be implemented by a processor, a central processing unit (CPU), or a system on chip (SoC), drive an operation system or an application, control a plurality of hardware or software components connected to the MCU 128, and execute various data processing and operations. The MCU 128 can be configured to execute at least one instruction stored in the memory 122 and store the execution result data in the memory 122.

[0108] FIG. 7 illustrates a CAN communication speed setting method according to an embodiment of the present invention.

[0109] Referring to FIG. 7, when the external device 10 is connected (S702) and the battery management device 120 is woken up (S704), the MCU 128 initializes the CAN communication speed to the communication speed stored in the memory 122 (S706). The battery management device 120 can be woken up when a signal for operating the external device 10 is input or a signal for turning on the battery pack 100 is input. Here, the communication speed stored in the memory 122 may mean the most recently used CAN communication speed.

[0110] When step S706 is executed, the MCU 128 diagnoses whether there is an abnormality in the battery pack 100 (S708). At this time, the MCU 128 can diagnose whether there is an abnormality in the battery pack 100 based on the battery state data detected through the detector 124.

[0111] If there is no abnormality in the battery pack 100 as a result of the diagnosis in step S708 (S710), the MCU 128 turns on the switch 130 (S712) and determines whether a CAN message frame is received from the external device 10 within a preset period of time (S714).

[0112] If, as a result of the determination in step S714, a CAN message frame is received from the external device 10 within a certain period of time, the MCU 128 checks whether there is an error detection in the CAN message frame received from the external device 10 (S716).

[0113] If, as a result of the inspection in step S716, an error is detected in the CAN message frame, the MCU 128 uses a counter to count the number of detected errors and determines whether the number of errors is equal to or greater than a threshold value (S718).

[0114] If, as a result of the determination in step S718, the number of errors is equal to or greater than the threshold value, the MCU 128 changes the initialized CAN communication speed to a different CAN communication speed (S720) and executes step S716.

[0115] If, as a result of the determination in step S718, the number of errors is not less than the threshold value, the MCU 128 executes step S716.

[0116] If, as a result of the inspection in step S716, no error is detected in the CAN message frame, the MCU 128 saves the initialized CAN communication speed as the final CAN communication speed (S722).

[0117] If, as a result of the determination in step S714, a CAN message frame is not received from the external device 10 within a certain period of time, the MCU 128 transmits a CAN message frame to the external device 10 (S724) and executes step S714.

[0118] If, as a result of the diagnosis in step S708, there is an abnormality in the battery pack 100, the MCU 128 turns off the switch 130 (S726).

[0119] FIG. 8 illustrates a CAN communication speed setting method according to another embodiment of the present invention.

[0120] Referring to FIG. 8, when the external device 10 is connected (S802) and the battery management device 120 is woken up (S804), the MCU 128 diagnoses whether there is an abnormality in the battery pack 100 (S806). At this time, the MCU 128 can diagnose whether there is an abnormality in the battery pack 100 based on the battery state data detected through the detection unit 124.

[0121] If there is no abnormality in the battery pack 100 based on the diagnosis result at step S806 (S808), the MCU 128 turns on the switch 130 (S810) and receives a CAN message frame from the external device 10 (S812).

[0122] When step S812 is executed, the MCU 128 calculates the time interval at which an interrupt occurs each time an interrupt occurs (S814). At this time, the interrupt can be set to occur at both the rising edge and the falling edge. Therefore, the MCU 128 can use a timer to calculate the time interval at which an interrupt occurs each time an interrupt occurs at the rising edge and the falling edge. At this time, the CAN RX Pin of the MCU 128 can be set to the external interrupt mode.

[0123] When step S814 is executed, the MCU 128 calculates the CAN communication speed based on the interrupt occurrence time interval within a preset fixed time (S816). At this time, the MCU 128 can select the minimum time (tmin) among the interrupt occurrence time intervals as 1 bit time (time) and calculate the communication speed using the selected minimum time. The MCU 128 can calculate the communication speed (baud rate) by calculating the reciprocal of the selected minimum time. That is, the MCU 128 can calculate "1 / minimum time" as the communication speed.

[0124] When step S816 is executed, the MCU 128 initializes the CAN communication speed to the communication speed most similar to the communication speed calculated using the communication speed table stored in the memory 122 (S818).

[0125] When the S818 stage is executed, the MCU 128 receives a CAN message frame from the external device 10 at the initialized CAN communication speed, and checks whether there is an error detection in the received CAN message frame (S820).

[0126] If an error is detected in the CAN message frame as a result of the inspection in the S820 stage, the MCU 128 executes the S814 stage.

[0127] If no error is detected in the CAN message frame as a result of the inspection in the S820 stage, the MCU 128 stores the initialized CAN communication speed as the final CAN communication speed (S822).

[0128] If there is an abnormality in the battery pack 100 as a result of the diagnosis in the S808 stage, the MCU 128 turns off the switch 130 (S824).

[0129] As described above, according to the present invention, when using one type of battery pack with various models of external devices (for example, LEV, xEV, ESS, etc.), the battery management device 120 automatically detects the communication speed of the external device and automatically sets the communication speed to match the external device. Thus, there is no need to provide a separate device for setting the communication speed, and it is possible to prevent operator errors.

[0130] The term "unit" used in this specification can include a unit implemented in hardware, software, or firmware, and can be used interchangeably with terms such as, for example, logic, logic block, component, or circuit. A "unit" can be an integrally configured component or the minimum unit or a part of the component that executes one or more functions. For example, according to one embodiment, a "unit" can be implemented in the form of an ASIC (Application-Specific Integrated Circuit).

[0131] The embodiments described in this specification may be embodied, for example, in a method or process, an apparatus, a software program, a data stream, or a signal. Even if discussed in the context of only a single form of embodiment (e.g., only as a method), the embodiments of the features discussed may also be embodied in other forms (e.g., an apparatus or a program). The apparatus may be embodied in appropriate hardware, software, firmware, and the like. The method may be embodied, for example, in an apparatus such as a processor that generally refers to a processing device including a computer, a microprocessor, an integrated circuit, or a programmable logic device. The processor may also include communication devices such as a computer, a cellular phone, a personal digital assistant (PDA), and other devices that facilitate the communication of information among end-users.

[0132] The present invention has been described with reference to the embodiments illustrated in the drawings, which are merely exemplary, and it will be understood by those of ordinary skill in the art to which the technology pertains that various modifications and equivalent other embodiments are possible therefrom. Therefore, the technical protection scope of the present invention should be determined by the following claims.

Claims

1. an interface unit that performs CAN (Controller Area Network) communication with an external device through a CAN bus line; and an MCU (Micro Controller Unit) that sets a CAN communication speed (baud rate) based on whether an error is detected in a CAN message frame received from the external device through the interface unit. Battery management device.

2. The MCU includes: When the battery management device wakes up, the battery management device initializes the CAN communication speed to a most recently used CAN communication speed, checks whether an error is detected in the CAN message frame received from the external device at the initialized CAN communication speed, and if no error is detected, sets the initialized CAN communication speed as a final CAN communication speed. The battery management device of claim 1 .

3. The MCU includes: When an error is detected in the CAN message frame, the number of detected errors is counted, and when the number of counted errors is equal to or greater than a preset threshold, the initialized CAN communication speed is changed to a different CAN communication speed, and it is checked whether an error is detected in the CAN message frame received from the external device at the changed CAN communication speed, and when no error is detected, the changed CAN communication speed is set as a final CAN communication speed. The battery management device according to claim 2 .

4. The MCU includes: a CAN communication speed different from the initialized CAN communication speed is obtained from a communication speed table in which a plurality of different CAN communication speeds are set, and the initialized CAN communication speed is changed to the obtained different CAN communication speed. The battery management device according to claim 3 .

5. The MCU includes:

5. The battery management device of claim 4, characterized in that when an error is detected in a CAN message frame received from the external device at the changed CAN communication speed, the number of detected errors is counted, and when the number of counted errors is equal to or greater than the threshold, the device continues to obtain a CAN communication speed that is not used in the communication speed table and change to the obtained CAN communication speed until no errors are detected.

6. The MCU includes: When a CAN receiving pin (CAN RX pin) is set to an external interrupt mode, the method includes: calculating an interrupt generation time interval each time an interrupt occurs; calculating a communication speed based on the interrupt generation time interval during a preset fixed time; obtaining a communication speed that is most similar to the calculated communication speed from a communication speed table; initializing the communication speed to the CAN communication speed; checking whether an error is detected in a CAN message frame received from the external device at the initialized CAN communication speed; and setting the initialized CAN communication speed as a final CAN communication speed if no error is detected. The battery management device of claim 1 .

7. The MCU includes: Each time the interrupt occurs at a rising edge and a falling edge, a timer is used to calculate the interrupt occurrence time interval. The battery management device according to claim 6.

8. The MCU includes: A minimum time among the interrupt generation time intervals during the fixed time is selected as 1 bit time, and the communication speed is calculated using the reciprocal of the selected minimum time. The battery management device according to claim 6.

9. The MCU includes: When an error is detected in the CAN message frame, a minimum time among the interrupt generation time intervals during a preset fixed time is selected as 1 bit time, the selected minimum time is used to calculate the communication speed, and a communication speed most similar to the calculated communication speed is obtained from the communication speed table to change the CAN communication speed. The battery management device according to claim 6.

10. A detection unit detects battery status data including at least one of a voltage, a current, and a temperature of the battery module, and transmits the detected battery status data to the MCU, The MCU diagnoses whether an abnormality occurs in the battery pack based on the battery state data, and if an abnormality does not occur in the battery pack, turns on a switch to receive the CAN message frame from an external device through the CAN bus line. The battery management device of claim 1 .

11. The MCU includes: If no error is detected in the CAN message frame, it is determined that the CAN communication speed is the same as the communication speed of the external device; When an error is detected in the CAN message frame, it is determined that the CAN communication speed is not the same as a communication speed of the external device, and the preset CAN communication speed is changed to a different CAN communication speed. The battery management device of claim 1 .

12. initializing, by the MCU, the CAN communication speed to the most recently used CAN communication speed when the battery management unit wakes up; Diagnosing whether an abnormality occurs in the battery pack based on the battery state data by the MCU; If no abnormality occurs in the battery pack, the MCU turns on a switch to receive a CAN message frame from an external device through a CAN bus line; checking by the MCU whether an error is detected in the CAN message frame, and setting the initialized CAN communication speed as a final CAN communication speed when no error is detected. How to set CAN communication speed.

13. Setting the initialized CAN communication speed as the final CAN communication speed includes: When an error is detected in the CAN message frame, the MCU counts the number of detected errors, and when the number of counted errors is equal to or greater than a preset threshold, the MCU changes the initialized CAN communication speed to a different CAN communication speed, checks whether an error is detected in a CAN message frame received from the external device at the changed CAN communication speed, and when no error is detected, sets the changed CAN communication speed as a final CAN communication speed. The CAN communication speed setting method according to claim 12.

14. Setting the initialized CAN communication speed to the final CAN communication speed includes: The MCU acquires a CAN communication speed different from the initialized CAN communication speed from a communication speed table in which a plurality of mutually different CAN communication speeds are set, and changes the initialized CAN communication speed to the acquired different CAN communication speed. The CAN communication speed setting method according to claim 13.

15. Setting the initialized CAN communication speed to a final CAN communication speed includes: When an error is detected in a CAN message frame received from the external device at the changed CAN communication speed, the MCU counts the number of detected errors, and when the number of counted errors is equal to or greater than the threshold, continues to acquire a CAN communication speed that is not used in the communication speed table and change to the acquired CAN communication speed until no errors are detected. The CAN communication speed setting method according to claim 14.

16. Diagnosing whether or not an abnormality occurs in the battery pack based on the battery state data by the MCU; If no abnormality occurs in the battery pack, the MCU turns on a switch to receive a CAN message frame from an external device through a CAN bus line; calculating an interrupt generation time interval by the MCU every time an interrupt occurs due to reception of the CAN message frame; Calculating a communication speed based on an interrupt generation time interval during a preset fixed time period by the MCU; obtaining a communication speed most similar to the calculated communication speed from a communication speed table by the MCU, and initializing the communication speed to a CAN communication speed; checking by the MCU whether an error is detected in a CAN message frame received from the external device at the initialized CAN communication speed, and if no error is detected, setting the initialized CAN communication speed as a final CAN communication speed. How to set CAN communication speed.

17. Calculating the interrupt occurrence time interval The MCU sets a CAN receiving pin (CAN RX pin) to an external interrupt mode and calculates an interrupt generation time interval. The CAN communication speed setting method according to claim 16.

18. Calculating the interrupt occurrence time interval The MCU calculates the interrupt generation time interval using a timer every time the interrupt occurs at a rising edge and a falling edge. The CAN communication speed setting method according to claim 17.

19. Calculating a communication speed based on the interrupt generation time interval The MCU selects a minimum time among the interrupt generation time intervals during the fixed time as 1 bit time, and calculates the communication speed using the reciprocal of the selected minimum time. The CAN communication speed setting method according to claim 16.

20. Setting the initialized CAN communication speed as the final CAN communication speed includes: When an error is detected in the CAN message frame, the MCU selects a minimum time among the interrupt generation time intervals during the fixed time as 1 bit time, calculates the communication speed using the selected minimum time, and obtains a communication speed that is most similar to the calculated communication speed from the communication speed table to change the CAN communication speed. The CAN communication speed setting method according to claim 16.

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