Battery management system

Abstract

A battery management system includes a control device (40) and monitoring devices (30) arranged in a case that houses a battery. The monitoring devices include (i) monitoring ICs (33) capable of acquiring battery information and (ii) wireless ICs (35). At a start-up time of the plurality of monitoring devices, each wireless IC performs an advertising operation in a periodic advertising event for establishing a connection of wireless communication between the plurality of monitoring devices and the control device, and the control device performs a scanning operation. The wireless IC of each of the two or more monitoring devices has an event management unit (352) that manages a generation period of the advertising event for performing the advertising operation at a respective different time, respectively.

Description

Technical Field

[0001] This disclosure generally relates to a battery management system. Background Technology

[0002] Patent document 1 (Japanese Patent No. 6093448) discloses a comparative battery management system. The disclosure of that comparative document is incorporated herein by reference as an explanation of the technical elements thereof.

[0003] Considering the ease of installation in vehicles and the like, comparative battery management systems are housed in a housing along with the battery to be monitored (i.e., together with the monitored target). Specifically, multiple battery cell management devices (i.e., monitoring devices) and a modular battery management device (i.e., control device) constituting the battery management system are arranged within the housing containing the battery. In this way, wireless communication occurs between the multiple monitoring devices and the control device within the housing. When the multiple monitoring devices are activated at startup, each device periodically performs a notification operation, which may cause radio wave interference. In view of the above points or other points not mentioned, the battery management system requires further improvement. Summary of the Invention

[0004] One object of this disclosure is to provide a battery management system capable of suppressing radio wave interference during startup.

[0005] The battery management system disclosed in this article includes:

[0006] Monitoring devices are arranged in a housing for containing batteries, and each monitoring device includes:

[0007] (i) A monitoring circuit capable of acquiring battery information indicating the battery's state, and

[0008] (ii) a monitor transceiver capable of performing wireless communication by sending data to and receiving data from the monitoring circuit; and

[0009] A control device, housed within a housing, performs predetermined processing based on battery information via wireless communication with various monitor transceivers in the monitoring device, wherein...

[0010] At the startup time of the monitoring device, each monitoring transceiver performs an announcement operation during a periodic advertising event to establish a wireless communication connection between the monitoring device and the control device, and the control device performs a scanning operation.

[0011] Each of the two or more monitoring devices has an event management unit that manages the generation cycle of the notification events so that notification operations can be performed at different times.

[0012] In one of the battery management systems disclosed above, the monitoring device with the event management unit is arranged at different positions on the circumference of a virtual circle centered on the control device. In another battery management system disclosed above, the monitoring device with the event management unit includes a first monitoring device and a second monitoring device, and the control device is arranged at the midpoint between the first and second monitoring devices. In yet another battery management system disclosed above, the monitoring device with the event management unit includes a third monitoring device and a fourth monitoring device, and the third and fourth monitoring devices are arranged symmetrically with respect to a virtual line passing through the control device.

[0013] According to the disclosed battery management system, each transceiver of the monitoring device has an event management unit that manages the generation cycle of the notification events. The transceiver with the event management unit can manage the event generation cycle to perform notification operations at different times. As a result, radio wave interference can be suppressed during startup.

[0014] The aspects disclosed in this specification employ different technical solutions to achieve their respective purposes. The reference numerals in parentheses described in the claims and this section exemplarily illustrate the correspondence between parts / configurations and the embodiments described later, and are not intended to limit the scope of the technology. The purposes, features, and advantages disclosed in this specification will become apparent from the following detailed description and drawings. Attached Figure Description

[0015] The purpose, features, and advantages of this disclosure will become more apparent from the following detailed description with reference to the accompanying drawings, in which:

[0016] Figure 1 It is a picture showing a vehicle equipped with a battery pack;

[0017] Figure 2 It is a plan view showing a schematic structure of a battery pack including a battery management system according to the first embodiment;

[0018] Figure 3 It is a diagram showing the positional relationship between the monitoring device and the control device;

[0019] Figure 4 It is a block diagram showing the structure of the battery management system;

[0020] Figure 5This is a diagram showing an example of the communication timing between the monitoring device and the control device;

[0021] Figure 6 This is a diagram showing an example of the communication timing until the connection is established;

[0022] Figure 7 This is a flowchart showing the notification processing.

[0023] Figure 8 This is a graph showing the generation cycle of notification events;

[0024] Figure 9 This is a graph showing the notification operation times of the two monitoring devices in the reference example;

[0025] Figure 10 This is a diagram showing the timing of the notification operations of the two monitoring devices in the first embodiment;

[0026] Figure 11 This is a flowchart showing the processes performed by the event management unit in the battery management system according to the second embodiment;

[0027] Figure 12 It is a graph showing the timing of the notification operations from the two monitoring devices;

[0028] Figure 13 This is a diagram explaining the reconnection;

[0029] Figure 14 This is a flowchart showing the processes performed by the event management unit in the battery management system according to the third embodiment;

[0030] Figure 15 This is another diagram showing the generation cycle of notification events;

[0031] Figure 16 It is a flowchart showing the notification process performed by the monitoring device;

[0032] Figure 17 It is a flowchart showing the scanning process performed by the control device;

[0033] Figure 18 This is a block diagram showing another example of the structure of a battery management system; and

[0034] Figure 19 This is another example of a diagram showing the positional relationship between a monitoring device and a control device. Detailed Implementation

[0035] In the following description, several embodiments will be illustrated with reference to the accompanying drawings. In each embodiment, the same reference numerals are assigned to corresponding elements, thus redundant descriptions may be omitted. In each embodiment, when only a portion of the configuration is described, the remainder of that configuration may be derived from corresponding portions of other embodiments. Furthermore, not only are combinations of configurations explicitly shown in the descriptions of the various embodiments, but configurations of multiple embodiments may also be partially combined even if they are not explicitly shown, provided that such combination is not particularly difficult.

[0036] (First Embodiment)

[0037] First, based on Figure 1 The structure of a vehicle equipped with a battery management system according to this embodiment, and particularly with respect to the structure of a battery pack equipped with the battery management system, will be described. Figure 1 This is a schematic diagram showing the structure of a vehicle. The vehicle is electrically powered, such as an electric vehicle or a hybrid vehicle.

[0038] <Vehicles>

[0039] like Figure 1 As shown, vehicle 10 includes a battery pack (BAT) 11, a power control unit 12, an electric generator 13, and an ECU 14. PCU is an abbreviation for Power Control Unit. MG is an abbreviation for Motor Generator. ECU is an abbreviation for Electronic Control Unit.

[0040] Battery pack 11 includes assembled battery 20, which will be described later, and provides a DC voltage source capable of being charged and discharged. Battery pack 11 supplies power to the electrical loads of vehicle 10. Battery pack 11 supplies power to electric generator (MG) 13 via power control unit (PCU) 12. Battery pack 11 is charged via power control unit 12. Battery pack 11 is sometimes referred to as the main battery.

[0041] The battery pack 11 is located in the front compartment of the vehicle 10, for example, as Figure 1 As shown. The battery pack 11 can also be located in the rear compartment, under the seats, under the floor, etc. For example, in the case of a hybrid vehicle, the compartment where the engine is located may sometimes be referred to as the engine compartment or engine room.

[0042] The power control unit 12 performs bidirectional power conversion between the battery pack 11 and the electric generator 13 based on control signals from the ECU 14. The power control unit 12 may sometimes be referred to as a power converter. The power control unit 12 includes, for example, an inverter. The inverter converts DC voltage to AC voltage, such as three-phase AC voltage, and outputs the AC voltage to the electric generator 13. The inverter converts the power generated by the electric generator 13 back to DC voltage and outputs that DC voltage to the converter. The power control unit 12 may include a converter. The converter is arranged in the power path between the battery pack 11 and the inverter. The converter has the function of increasing and decreasing DC voltage.

[0043] The electric generator 13 is an AC rotating motor, such as a three-phase AC synchronous motor with permanent magnets embedded in the rotor. The electric generator 13 serves as the driving power source for the vehicle 10, i.e., the electric motor. The electric generator 13 is driven by the power control unit 12 to generate rotational driving force. The driving force generated by the electric generator 13 is transmitted to the drive wheels. The electric generator 13 acts as a generator when the vehicle 10 is braked and performs regenerative power generation. The electricity generated by the electric generator 13 is supplied to the battery pack 11 via the power control unit 12 and stored in the assembled batteries 20 within the battery pack 11.

[0044] ECU 14 is configured to include a computer, which includes a processor, memory, input / output interfaces, buses connecting them, etc. The processor is hardware used for arithmetic processing. The processor includes, for example, a CPU as its core. CPU is an abbreviation for Central Processing Unit. Memory is a non-transitory, physical storage medium that non-transitory stores or remembers programs and data that can be read by a computer. Memory stores various programs executed by the processor.

[0045] ECU 14 obtains information about the assembled battery 20 from battery pack 11, for example, and controls power control unit 12 to control the drive of electric generator 13 and the charging / discharging of battery pack 11. ECU 14 can obtain information from battery pack 11 such as the voltage, temperature, current, state of charge (SOC), and state of health (SOH) of the assembled battery 20. ECU 14 can obtain battery information of the assembled battery 20, such as voltage, temperature, and current, to calculate SOC and SOH. SOC is an abbreviation for State of Charge. SOH is an abbreviation for State of Health.

[0046] The processor of ECU 14 executes multiple instructions contained in a PCU control program, for example, stored in memory. As a result, ECU 14 constructs multiple functional units for controlling the power control unit 12. In ECU 14, multiple functional units are constructed / provided by causing the processor to execute multiple instructions under the control of a program stored in memory. ECU 14 may be referred to as an EV ECU.

[0047] <Battery Pack>

[0048] Next, refer to Figure 2 This describes a configuration example for battery pack 11. Figure 2 This is a plan view showing the internal structure of battery pack 11. Figure 2 In the diagram, the shell is represented by a double-dotted line.

[0049] like Figure 2 As shown, the battery pack 11 includes an assembled battery 20, multiple monitoring devices 30, a control device 40, and a housing 50.

[0050] The housing 50 houses other components constituting the battery pack 11, namely the assembled battery 20, the monitoring device 30, and the control device 40. The housing 50 can be formed of either a metallic or resin material. The housing 50 may have both metallic and resin portions. The housing 50 has a generally rectangular parallelepiped shape. Figure 2 In this design, the longitudinal direction of the mounting surface of the housing 50 on the vehicle 10 is represented by the X direction, and its transverse direction is represented by the Y direction. Furthermore, the vertical direction perpendicular to the mounting surface is represented by the Z direction. The X, Y, and Z directions are orthogonal to each other. In the following text, unless otherwise specified, the shape observed in a plane from the Z direction, i.e., the shape along the XY plane defined by the X and Y directions, is referred to as the planar shape. Furthermore, the planar view observed from the Z direction is simply referred to as the planar view.

[0051] In this embodiment, the left-right direction of the vehicle 10 corresponds to the X direction, the front-back direction corresponds to the Y direction, and the up-down direction corresponds to the Z direction. The direction from the battery stack 21 towards the monitoring device 30 is the upward direction, and the direction from the monitoring device 30 towards the battery stack 21 is the downward direction. The mounting surface of the housing 50 on the vehicle 10 is the downward surface relative to the battery stack 21. Figure 2 The arrangement may be merely an example, and the battery pack 11 may be arranged in any direction relative to the vehicle 10.

[0052] The assembled battery 20 has multiple battery stacks 21 arranged side-by-side in the X direction. The battery stacks 21 can also be referred to as battery blocks or battery modules. The assembled battery 20 is constructed by connecting multiple battery stacks 21 in series. Each battery stack 21 has multiple battery cells 22. The battery stack 21 has multiple battery cells 22 connected in series. In this embodiment, the battery stack 21 is constructed by connecting multiple battery cells 22 arranged side-by-side in the Y direction in series. The assembled battery 20 provides the aforementioned DC voltage source. The assembled battery 20, battery stacks 21, and battery cells 22 correspond to batteries.

[0053] Battery element 22 is a secondary battery that generates electromotive force through a chemical reaction. Examples of secondary batteries include lithium-ion batteries and nickel-metal hydride batteries. Lithium-ion batteries use lithium as the charge carrier. In addition to general lithium-ion batteries with a liquid electrolyte, so-called all-solid-state batteries using a solid electrolyte can also be included.

[0054] On the upper surface of each battery stack 21, linear bus bar units 23 are arranged at both ends in the X direction. That is, a pair of bus bar units 23 are arranged in each battery stack 21. The bus bar units 23 electrically connect multiple battery cells 22. Each battery cell 22 is formed in a flat shape and is laminated / stacked such that its sides overlap each other in the Y direction. The battery cell 22 has positive and negative terminals (not shown) protruding in the Z direction (more specifically, in the upward direction) at both ends in the X direction. The battery cells 22 are stacked such that the positive and negative terminals are arranged alternately in the Y direction.

[0055] Each busbar unit 23 has multiple busbars and busbar covers (not shown). The busbars are plate-shaped members made of a metal with good conductivity, such as copper. The busbars electrically connect the positive and negative terminals of adjacent battery cells 22 in the Y direction. As a result, in each battery stack 21, multiple battery cells 22 are connected in series. Note that in each battery stack 21, the positive terminal of the battery cell 22 at one end arranged in the Y direction is connected to a predetermined positive wiring, and the negative terminal of the battery cell 22 at the other end arranged in the Y direction is connected to a predetermined negative wiring.

[0056] The busbar cover is formed using an electrically insulating material such as resin. The busbar cover is linearly arranged along the Y direction from one end of the battery stack 21 to the other to cover multiple busbars.

[0057] A monitoring device 30 is installed for each of the multiple battery stacks 21. For example... Figure 2As shown, the monitoring device 30 is arranged between a pair of bus units 23 in each battery stack 21. The monitoring device 30 is fixed to the bus unit 23 using screws or similar means. The monitoring device 30 has a circuit board (not shown) and is fixed such that the thickness direction of the circuit board is substantially aligned with the Z-direction. As described later, the monitoring device 30 is configured to communicate wirelessly with the control device 40. The antenna 37 (described later) included in the monitoring device 30 is arranged so as not to overlap with the bus unit 23 in the Z-direction, i.e., it protrudes upward from the bus unit 23 in the Z-direction.

[0058] The control device 40 is positioned between the battery stacks 21 in the X direction. The control device 40 has a circuit board (not shown), and the thickness direction of the circuit board is arranged approximately in line with the X direction. The control device 40 can be fixed, for example, to the side of the battery stacks 21, or to the lower surface of the housing 50. The control device 40 is configured to wirelessly communicate with each of the monitoring devices 30. The antenna 42 included in the control device 40 (described later) is arranged at approximately the same height in the Z direction as the antenna 37 of the monitoring device 30. That is, the antenna 42 included in the control device 40 is positioned to protrude from the bus unit 23 in the Z direction.

[0059] In the battery pack 11, the monitoring device 30 and the control device 40 provide a battery management system 60. That is, the battery pack 11 is equipped with a battery management system 60.

[0060] <Positional relationship between monitoring device and control device>

[0061] Next, refer to Figure 2 and Figure 3 The positional relationship between the multiple monitoring devices 30 and the control device 40 housed in the housing 50 is explained. Figure 3 It is a display Figure 2 A diagram showing the positional relationship between the multiple monitoring devices 30 and the control device 40 in the battery pack 11. Figure 3 In the diagram, monitoring device 30 is displayed as SBM, and control device 40 is displayed as ECU. SBM is an abbreviation for Satellite Battery Module. Figure 3 In the plan view, the virtual circle centered on the control device 40 is displayed by a single-dotted line. The virtual straight line IL passing through the control device 40 is displayed by a double-dotted line.

[0062] like Figure 2 and Figure 3As shown, the battery pack 11 includes multiple monitoring devices 30 and a control device 40. The multiple monitoring devices 30 include monitoring device 30A, monitoring device 30B, monitoring device 30C, monitoring device 30D, monitoring device 30E, monitoring device 30F, monitoring device 30G, and monitoring device 30H. The multiple monitoring devices 30 are arranged side by side in the X direction in the order of monitoring device 30G, monitoring device 30E, monitoring device 30C, monitoring device 30A, monitoring device 30B, monitoring device 30D, monitoring device 30F, and monitoring device 30H.

[0063] In the plan view, two or more of the plurality of monitoring devices 30 are arranged at different positions on the circumference of a virtual circle centered on the control device 40. This circle is a complete circle / true circle. For example, the number of monitoring devices 30 arranged on a single circle can be two, or it can be three or more. All monitoring devices 30 can be arranged on the circumference of a single circle.

[0064] In this embodiment, two monitoring devices 30 are arranged on a circumference (i.e., on a virtual circle). These virtual circles are concentric, and two monitoring devices 30 are arranged on the circumference of each virtual circle. Instead of being arranged on the circumferences of multiple circles, a single monitoring device 30 is arranged on the circumference of a single circle. Specifically, monitoring devices 30A and 30B are arranged on the circumference of the first circle, which is closest to the control device 40. Monitoring devices 30C and 30D are arranged on the circumference of the second circle, which is outside and adjacent to the first circle. Monitoring devices 30E and 30F are arranged on the circumference of the third circle, which is outside the second circle. Monitoring devices 30G and 30H are arranged on the circumference of the fourth circle, which is outside the third circle. The two monitoring devices 30 arranged on the same circle have a double symmetry centered on the control device 40.

[0065] Furthermore, in the plan view, the two monitoring devices 30 are arranged symmetrically with respect to the virtual straight line IL passing through the control device 40. This symmetrical arrangement can include not only the two monitoring devices 30 being completely symmetrical with respect to the straight line IL, but also the two monitoring devices 30 being approximately symmetrical with respect to the straight line IL. One of the two symmetrically arranged monitoring devices 30 corresponds to the first monitoring device, and the other corresponds to the second monitoring device. The straight line IL extends in a direction orthogonal to the alignment direction of the two monitoring devices 30. Specifically, the straight line IL extends in the Y direction. Monitoring devices 30A and 30B are arranged symmetrically with respect to the straight line IL. Monitoring devices 30C and 30D are arranged symmetrically with respect to the straight line IL. Monitoring devices 30E and 30F are arranged symmetrically with respect to the straight line IL. Monitoring devices 30G and 30H are arranged symmetrically with respect to the straight line IL. Monitoring devices 30A, 30C, 30E, and 30G are arranged symmetrically with respect to monitoring devices 30B, 30D, 30F, and 30H with respect to the straight line IL. That is, all monitoring devices 30 are arranged symmetrically with respect to the straight line IL.

[0066] Furthermore, in the plan view, the control device 40 is positioned at the midpoint between the two monitoring devices 30. The midpoint can be defined not only as a state where the distance between the control device 40 and each monitoring device 30 is precisely equal, but also as a state where the distances are nearly equal. One of the two monitoring devices 30 corresponds to a third monitoring device, and the other corresponds to a fourth monitoring device. Specifically, the control device 40 is approximately positioned at the center of the plurality of monitoring devices 30 in the X direction. The control device 40 is positioned between monitoring devices 30A and 30B in the X direction. The control device 40 is positioned at the midpoint between monitoring devices 30A and 30B in the X direction. Similarly, the control device 40 is positioned at the midpoint between monitoring devices 30C and 30D in the X direction. The control device 40 is positioned at the midpoint between monitoring devices 30E and 30F in the X direction. The control device 40 is positioned at the midpoint between monitoring devices 30G and 30H in the X direction.

[0067] Battery Management System

[0068] Next, refer to Figure 4 Explain the schematic structure of the battery management system. Figure 4 It is a block diagram showing the configuration of the battery management system.

[0069] like Figure 4As shown, the battery management system 60 includes a control unit (ECU) 40 and multiple management units (SBMs) 30. The control unit 40 may be referred to as a battery ECU or BMU. BMU is an abbreviation for Battery Management Unit. The battery management system 60 is a system that manages the battery using wireless communication. In the battery management system 60, wireless communication occurs between a control unit 40 and multiple monitoring units 30.

[0070] <Monitoring Device>

[0071] First, the monitoring device 30 is described. Since the configuration of the monitoring device 30 is almost identical to that of all devices 30, the common configuration is described below. The monitoring device 30 includes a power supply circuit (PSC) 31, a multiplexer (MUX) 32, a monitoring IC (MIC) 33, a microcomputer (MC) 34, a wireless IC (WIC) 35, a front-end circuit (FE) 36, and an antenna (ANT) 37. Communication between these components in the monitoring device 30 is via cables.

[0072] Power supply circuit 31 uses the voltage supplied from battery stack 21 to generate operating power for operating other circuit elements included in monitoring device 30. In this embodiment, power supply circuit 31 includes power supply circuits 311, 312, and 313. Power supply circuit 311 uses the voltage supplied from battery stack 21 to generate a predetermined voltage and supplies it to monitoring IC 33. Power supply circuit 312 uses the voltage generated by power supply circuit 311 to generate a predetermined voltage and supplies it to microcomputer 34. Power supply circuit 313 uses the voltage generated by power supply circuit 311 to generate a predetermined voltage and supplies it to wireless IC 35.

[0073] Multiplexer 32 is a selection circuit that takes the detection signals from the multiple sensors 70 included in the battery pack 11 as inputs and outputs them as a single signal. Multiplexer 32 selects (i.e., switches) the inputs based on a selection signal from monitoring IC 33 and outputs them as a single signal. Sensors 70 include sensors that detect physical quantities of each battery cell 2, sensors for determining / identifying which of the multiple battery cells 22 is currently involved, etc. Physical quantity detection sensors include, for example, voltage sensors, temperature sensors, current sensors, etc.

[0074] The monitoring IC 33 senses (i.e., acquires) battery information, such as cell voltage, cell temperature, and cell status, via multiplexer 32, and sends the battery information to microcomputer 34. The monitoring IC 33 is sometimes referred to as a Cell Supervising Circuit (CSC). CSC is an abbreviation for Cell Supervising Circuit. The monitoring IC 33 may have the following functions: (i) performing fault diagnosis on the circuitry of the monitoring device 30 (including the IC 33 itself), and (ii) sending the diagnostic results along with the battery information as monitoring data. When the monitoring IC 33 receives data requesting the acquisition of battery information sent from microcomputer 34, the monitoring IC 33 senses (i.e., picks up) the battery information via multiplexer 32 and sends monitoring data, including at least the battery information, to microcomputer 34. The monitoring IC 33 corresponds to a monitoring unit.

[0075] The microcomputer 34 is a microcomputer equipped with a CPU as a processor, ROM and RAM as memory, input / output interfaces, and buses for connecting them. The CPU constitutes multiple functional units by executing various programs stored in ROM while using the temporary storage function of RAM. ROM is an abbreviation for Read Only Memory. RAM is an abbreviation for Random Access Memory.

[0076] The microcomputer 34 controls the sensing and self-diagnostic schedule (or process) via the monitoring IC 33. The microcomputer 34 receives monitoring data sent from the monitoring IC 33 and transmits it to the wireless IC 35. The microcomputer 34 also sends data requesting battery information to the monitoring IC 33. As an example, when the microcomputer 34 in this embodiment receives data requesting battery information from the wireless IC 35, it sends the data requesting battery information to the monitoring IC 33.

[0077] The wireless IC 35 includes an RF circuit (RF) 350 and a microcomputer (MC) 351 for wirelessly transmitting and receiving data. The wireless IC 35 has a transmission function that modulates the transmitted data and oscillates at the frequency of the RF signal. The wireless IC 35 also has a reception function for demodulating the received data. RF is an abbreviation for Radio Frequency.

[0078] The wireless IC 35 modulates the data containing battery information transmitted from the microcomputer 34 and transmits it to the control device 40 via the front-end circuitry 36 and antenna 37. The wireless IC 35 adds data necessary for wireless communication, such as communication control information, to the transmitted data including the battery information and transmits that data. Data required for wireless communication includes, for example, identifiers (IDs) and error detection codes. The wireless IC 35 controls the data size, communication format, schedule (process), error detection, etc., of the communication between the SBM 30 and the control device 40.

[0079] The wireless IC 35 receives data transmitted from the control device 40 via the antenna 37 and the front-end circuitry 36, and demodulates the data. When the wireless IC 35 receives data, for example, including a request to acquire and transmit battery information, the wireless IC 35 acquires monitoring data containing battery information via the monitoring IC 33, and transmits the monitoring data to the control device 40 in response to the request. The wireless IC 35 corresponds to a wireless circuit unit.

[0080] The wireless IC 35 has an event management unit (EM) 352. The event management unit 352 manages the generation cycle of advertising events for the wireless IC 35 to perform advertising operations. For example, the event management unit 352 is one of the functional units, for example, constructed by a CPU, that executes various programs stored in ROM while utilizing the temporary storage function of RAM in the microcomputer 351 included in the wireless IC 35. Advertising operations and event management will be described later.

[0081] The front-end circuit 36 ​​has a matching circuit for impedance matching between the wireless IC 35 and the antenna 37, and a filtering circuit for removing unwanted frequency components.

[0082] Antenna 37 converts the RF signal, which is an electrical signal, into radio waves and transmits it into space. Antenna 37 receives radio waves propagating in space and converts them into electrical signals.

[0083] <Control Device>

[0084] Next, refer to Figure 4 The control device 40 is described below. The control device 40 includes a power supply circuit (PSC) 41, an antenna (ANT) 42, a front-end circuit (FE) 43, a wireless IC (WIC) 44, a main microcomputer (MMC) 45, and a sub-microcomputer (SMC) 46. Communication between each of these components in the control device 40 is via cables.

[0085] Power supply circuit 41 uses the voltage supplied from battery (BAT) 15 to generate operating power for running other circuit elements included in control device 40. Battery 15 is a DC (direct current) voltage source installed on vehicle 10 and is different from battery pack 11. Battery 15 is sometimes referred to as an auxiliary battery because it provides power to auxiliary devices of vehicle 10. In this embodiment, power supply circuit 41 includes power supply circuits 411 and 412. Power supply circuit 411 uses the voltage supplied from battery 15 to generate a predetermined voltage and supplies this voltage to main microcomputer 45 and auxiliary microcomputer 46. For simplicity of the drawings, the electrical connection between power supply circuit 411 and auxiliary microcomputer 46 is omitted. Power supply circuit 412 uses the voltage generated by power supply circuit 411 to generate a predetermined voltage and supplies it to wireless IC 44.

[0086] Antenna 42 converts the RF signal, which is an electrical signal, into radio waves and transmits it into space. Antenna 42 receives radio waves propagating in space and converts them into electrical signals.

[0087] The front-end circuit 43 includes a matching circuit for impedance matching between the wireless IC 44 and the antenna 42, and a filtering circuit for removing unwanted frequency components.

[0088] Wireless IC 44 has RF circuitry for wirelessly transmitting and receiving data and a microcomputer. Similar to Wireless IC 35, Wireless IC 44 has both transmitting and receiving functions. Wireless IC 44 receives data transmitted from monitoring device 30 via antenna 42 and front-end circuitry 43, and demodulates the data. The monitoring data, containing battery information, is then sent to main microcomputer 45. Wireless IC 44 receives data transmitted from main microcomputer 45, modulates it, and transmits it to monitoring device 30 via front-end circuitry 43 and antenna 42. Wireless IC 44 adds data required for wireless communication (such as communication control information) to the transmitted data and transmits it. Data required for wireless communication includes, for example, an identifier (ID) and an error detection code. Wireless IC 44 controls the data size, communication format, schedule, error detection, etc., of the communication between monitoring device 30 and control device 40.

[0089] The main microcomputer 45 is a microcomputer equipped with a CPU, ROM, RAM, input / output interfaces, and buses connecting them. The ROM stores various programs executed by the CPU. The main microcomputer 45 generates a command requesting the monitoring device 30 to process monitoring data containing battery information, and sends transmission data containing the command to the wireless IC 44. In this embodiment, the main microcomputer 45 generates a command requesting the acquisition and transmission of monitoring data containing battery information. This request may also be referred to herein as an instruction.

[0090] The main microcomputer 45 receives monitoring data containing battery information transmitted from the wireless IC 44 and performs predetermined processing based on the monitoring data. For example, the main microcomputer 45 performs processing to send the acquired battery information to the ECU 14. The main microcomputer 45 can calculate the SOC and / or SOH based on the battery information and can send the battery information including the calculated SOC and / or SOH to the ECU 14. The main microcomputer 45 can perform equalization processing to equalize the voltage of each battery cell 22 based on the battery information. The main microcomputer 45 can acquire the IG signal of the vehicle 10 and perform the above processing according to the driving state of the vehicle 10. The main microcomputer 45 can perform processing to detect anomalies in the battery cells 22 based on the battery information, or it can send anomaly detection information to the ECU 14.

[0091] The sub-microcomputer 46 is a microcomputer equipped with a CPU, ROM, RAM, input / output interfaces, and buses connecting them. The ROM stores various programs executed by the CPU.

[0092] The secondary microcomputer 46 performs monitoring processing for monitoring components / data in the monitoring and control device 40. For example, the secondary microcomputer 46 can monitor data exchanged between the wireless IC 44 and the main microcomputer 45. The secondary microcomputer 46 can also monitor the status of the main microcomputer 45.

[0093] The secondary microcomputer 46 can monitor the status of the wireless IC 44.

[0094] Wireless Communication

[0095] Next, refer to Figure 5 This describes the wireless communication between the monitoring device 30 and the control device 40. Figure 5 This is a diagram showing an example of the communication timing between the monitoring device 30 and the control device 40. Figure 5 Wireless communication between one of the monitoring devices 30 and the control device 40 is described. Figure 5 In this context, monitoring IC 33 is designated as MIC33, wireless IC 35 as WIC35, and control device 40 as ECU 40.

[0096] like Figure 5 As shown, the wireless IC 35 of the monitoring device 30 establishes a wireless communication connection with the control device 40 (step S10). The connection establishment process will be described later.

[0097] When a connection is established, the wireless IC 35 and the control device 40 then perform a pairing process (step S20). Specifically, this involves exchanging specific information, i.e., pairing, for encrypted communication. The pairing process ends when the pairing information remains between the wireless IC 35 and the control device 40, i.e., when they are in a paired state.

[0098] When pairing is complete, wireless circuit unit 35 and control device 40 communicate data. For example... Figure 5 As shown, the control device 40 sends request data to the monitoring device 30 (step S30), that is, sends sending data including a request to acquire and send monitoring data containing battery information.

[0099] When the wireless IC 35 of the monitoring device 30 receives the request data, the wireless IC 35 sends an acquisition request to the monitoring IC 33 to obtain monitoring data containing battery information (step S31). In this embodiment, the wireless IC 35 sends the acquisition request to the monitoring IC 33 via the microcomputer 34.

[0100] Upon receiving an acquisition request, the monitoring IC 33 performs sensing (step S32). The monitoring IC 33 performs sensing via the multiplexer 32 and acquires battery information for each battery cell 22. Additionally, the monitoring IC 33 performs circuit fault diagnosis.

[0101] Next, the monitoring IC 33 sends monitoring data containing battery information to the wireless IC 35 (step S33). In this embodiment, the monitoring data containing fault diagnosis results is sent together with the battery information. The monitoring IC 33 sends data to the wireless IC 35 via the microcomputer 34.

[0102] When the wireless IC 35 receives the monitoring data acquired by the monitoring IC 33, the wireless IC 35 will send the transmission data, i.e. the response data, including the monitoring data to the control device 40 (step S34).

[0103] When the control device 40 receives the response data, it performs a predetermined process based on the monitoring data (step S35). Note that the control device 40 that performs the request processing can be referred to as the master device, and the monitoring device 30 that performs the response processing can be referred to as the slave device.

[0104] The processes described in steps S10 to S35 are performed between each of the monitoring devices 30 and the control device 40. For example, the battery management system 60 first executes the processes in steps S10 and S20. After executing the processes in steps S10 and S20, data communication processes, namely the processes in steps S30 to S35, are performed periodically.

[0105] <Connection Establishment Processing>

[0106] Next, refer to Figure 6 This explains the processing of step S10 above, namely the connection establishment process. Figure 6 This is a diagram showing an example of the communication timing until the connection is established. Figure 6 Corresponding to Figure 5 .

[0107] Each of the monitoring devices 30 and the control device 40 executes steps S10 and S20 during startup. Startup refers to, for example, the time when operating power is supplied. In a configuration where operating power is continuously supplied from the battery stack 21 and the battery 15, the vehicle is started after the manufacturing process of the vehicle 10 or after parts are replaced at a repair shop. Startup can also be the time when a start signal, such as an IG signal, is supplied. For example, startup occurs when the IG signal is switched from off to on by user operation. During startup, steps S10 and S20 are executed between the control device 40 and all the monitoring devices 30 that have established wireless communication with the control device 40.

[0108] like Figure 6 As shown, firstly, the control device 40 performs a scanning operation (step S11), and the wireless IC 35 performs an announcement operation (step S12). The scanning operation may begin earlier than the announcement operation, or they may begin at approximately the same time. Alternatively, the scanning operation may begin later than the announcement operation. The control device 40 that performs the scanning operation may sometimes be referred to as a central device or a scanner. The wireless IC 35 that performs the announcement operation may sometimes be referred to as a peripheral device or an announcer.

[0109] The wireless IC 35 performs an announcement operation to notify the control device 40 of its presence. The event management unit 352 of the wireless IC 35 periodically generates announcement events. The wireless IC 35 sends an announcement packet (ADV_PKT) for each announcement event. That is, the wireless IC 35 periodically performs the announcement operation. The announcement packet includes its own ID information and ECU 14, etc. At startup, the wireless ICs 35 of multiple monitoring devices 30 send announcement packets to the control device 40. The announcement packet may sometimes be referred to as an announcement frame, announcement data, etc.

[0110] When the control device 40 detects an advertisement packet, i.e. a wireless IC 35, through a scanning operation, the control device 40 sends a connection request (CONNECT_RQ) to the detected wireless IC 35 (step S13).

[0111] Then, when the wireless IC 35 receives a connection request, a connection is established between a monitoring device 30 and a control device 40 (step S14). The wireless IC 35 of the monitoring device 30 with the established connection stops sending announcement packets. The control device 40 continues the scanning operation until a connection is established with the wireless IC 35 of all monitoring devices 30. The monitoring device 30 periodically performs announcement operations until a connection is established with the control device 40.

[0112] <Advertising event>

[0113] Next, refer to Figure 7 and Figure 8 Explanation of the announcement event. Figure 7 This is a flowchart illustrating an example of event management processing performed by the event management unit 352 of the wireless IC 35. The event management unit 352 performs the following processing during the connection establishment process (step S10).

[0114] like Figure 7 As shown, the event management unit 352 of the wireless IC 35 generates a notification event (step S100). The event management unit 352 generates the first notification event after the wireless IC 35 starts up, referencing the startup of the wireless IC 35. In this embodiment, the generation time of the first notification event is substantially the same for multiple wireless ICs 35. The wireless IC 35 sends a notification packet in response to the notification event.

[0115] Next, the event management unit 352 randomly sets the period (step S110). That is, the event management unit 352 sets a random duration as the "period" of the notification event. The event management unit 352 uses a unique value held by the wireless IC 35, such as the ID or address identifying the network interface, to calculate and set the period using a specific function such as a generator polynomial. Instead of using the aforementioned unique values, the wireless IC 35 uses input information from components of the monitoring device 30 other than the wireless IC 35, such as monitoring information acquired by the monitoring IC 33 and commands (instructions) from the microcomputer 34, to calculate and set the period using a specific function such as a generator polynomial. In other words, the event management unit 352 uses values ​​specific to the monitoring device 30, including the associated event management unit 352, to calculate and set the period using a specific function such as a generator polynomial.

[0116] In this way, the event management unit 352 randomly sets the period by using an operation of a specific function, such as a generator polynomial. That is, a random number is set as the period. In this embodiment, as an example, the period is randomly set by (i) calculating a delay amount using a specific function and (ii) adding such a delay to a predetermined period. The predetermined period is a value common to multiple monitoring devices 30.

[0117] Next, the event management unit 352 determines whether a connection request has been received from the control device 40 (step S120). When the event management unit 352 receives a connection request within the period set in step S110, the event management unit 352 stops generating notification events (step S130) and ends a series of processes.

[0118] On the other hand, if no connection request is received within the period set in step S110, the event management unit 352 will re-execute the processing after step S100 when the period set in step S110 expires. That is, when the period set in step S110 expires, the event management unit 352 will generate a new notification event.

[0119] In the above event management process, steps S120 and S130 can be performed by the wireless IC 35 as a combined process for determining the continuation and stopping of the notification operation. The period setting process can be performed before the notification event generation process, or the two processes can be performed in parallel.

[0120] Figure 8 This is a graph showing the generation cycle of notification events. Figure 8 In the diagram, the notification event is displayed as EVT, the generation period of the notification event is displayed as T, the aforementioned predetermined period is displayed as INT, and the delay amount is displayed as DLY.

[0121] As described above, the predetermined period INT is a value shared by multiple monitoring devices 30. The delay amount DLY is a random value, i.e., a random number, calculated by the event management unit 352 using a specific function. In this way, the event management unit 352 randomly sets the generation period T of the notification event. Figure 8 In the example, the first period T1 and the second period T2 are different because the delay DLY is different at each position.

[0122] <Summary of the First Embodiment>

[0123] Figure 9 This is a graph showing the timing of the notification operations of the two monitoring devices 30 in the reference example. Figure 10 This is a diagram showing the notification operation times of the two monitoring devices 30 in the battery management system 60 according to this embodiment. Figure 9 and Figure 10In the diagram, monitoring devices 30A and 30B are shown as two monitoring devices 30. Monitoring device 30A is referred to as SBM 30A, and monitoring device 30B is referred to as SBM 30B.

[0124] The wireless IC 35 of the monitoring devices 30A and 30B in the reference example does not have the aforementioned event management unit 352. In each wireless IC 35, the generation time of the first notification event after startup is substantially the same for each other. Each wireless IC 35 generates notification events at a common cycle. Therefore, as... Figure 9 As shown, the notification operations of monitoring devices 30A and 30B overlap periodically (repeatedly). Therefore, if monitoring devices 30A and 30B send notification packets upon startup, radio wave interference may occur.

[0125] In this embodiment, the wireless IC 35 of monitoring devices 30A and 30B each has an event management unit 352. The event management unit 352 randomly sets the generation cycle of notification events. Therefore, as Figure 10 As shown, it is possible to prevent the notification operations of monitoring devices 30A and 30B from overlapping periodically / repeatedly. Therefore, even if monitoring devices 30A and 30B send notification packets upon startup, radio wave interference is less likely to occur compared to the reference example.

[0126] As described above, in the battery management system 60 according to this embodiment, the event management unit 352 manages the generation cycle of notification events so that notification operations are performed at different times. Specifically, the event management unit 352 uses values ​​specific to the monitoring device 30 having the event management unit 352 to randomly set the generation cycle of notification events using a specific function such as a generator polynomial. Therefore, even if multiple monitoring devices 30 perform notification operations at startup, the occurrence of radio wave interference can be suppressed. In this embodiment, since the period of the notification event changes randomly each time, the possibility of avoiding external noise, etc., can be improved. In particular, the possibility of avoiding periodic noise can be improved. That is, a reliable connection can be established.

[0127] A control device 40 and multiple monitoring devices 30 constituting the battery management system 60 are housed within the casing 50 of the battery pack 11. The control device 40 and the multiple monitoring devices 30 are arranged in an enclosed space (i.e., a limited, narrow / small space). Within this enclosed space, wireless communication is performed between one control device 40 and the multiple monitoring devices 30, i.e., one-to-many wireless communication. In this embodiment, each of the multiple monitoring devices 30 has an event management unit 352. The event management unit 352 randomly sets the generation cycle for notification events in the multiple monitoring devices 30. Therefore, even if the multiple monitoring devices 30 perform notification operations upon startup, the occurrence of radio wave interference can be suppressed. Although in Figure 10The diagram shows two monitoring devices 30A and 30B. The generation time of the notification event (i.e., the time of the notification operation) can similarly move (change) between the other devices 30, i.e., between devices 30A and 30H.

[0128] In this embodiment, for example, two monitoring devices 30A and 30B are arranged on the circumference of a virtual circle centered on the control device 40. The monitoring devices 30A and 30B arranged in this way have approximately the same distance from the control device 40 in a plan view. However, each monitoring device 30A and 30B has an event management unit 352. Therefore, even if each monitoring device 30A and 30B performs an announcement operation upon startup, the occurrence of radio wave interference can be suppressed.

[0129] In this embodiment, a virtual circle centered on the control device 40 is used as a concentric circle, and two monitoring devices 30 are arranged on each of these concentric circles. Monitoring devices 30A and 30B are arranged on the circumference of the first circle. Monitoring devices 30C and 30D are arranged on the circumference of the second circle. Monitoring devices 30E and 30F are arranged on the circumference of the third circle. Monitoring devices 30G and 30H are arranged on the circumference of the fourth circle. Therefore, even if each of the monitoring devices 30 arranged on the same circumference performs an announcement operation upon startup, the occurrence of radio wave interference can be suppressed.

[0130] The number of monitoring devices 30 arranged on the circumference of a circle is not limited to two. Three or more monitoring devices 30 may also be arranged on the circumference of a circle. An example is shown in concentric circles where the number of monitoring devices 30 arranged on the circumference of each circle is equal, but this disclosure is not limited to such a configuration. For example, the number of monitoring devices 30 may differ between the first and second circles. In this embodiment, the example of concentric circles is shown as a virtual circle, but this disclosure is not limited to such a configuration. Only one circle may be used.

[0131] In this embodiment, for example, two monitoring devices 30A and 30B are arranged symmetrically with respect to the virtual straight line IL passing through the control device 40. Monitoring devices 30A and 30B arranged in this manner have approximately the same distance from the control device 40 in a plan view. However, each monitoring device 30A and 30B has an event management unit 352. Therefore, even if each monitoring device 30A and 30B performs an announcement operation upon startup, the occurrence of radio wave interference can be suppressed. This also applies to the positional relationship between monitoring devices 30C and 30D, between monitoring devices 30E and 30F, and between monitoring devices 30G and 30H.

[0132] In this embodiment, the control device 40 is arranged at, for example, the midpoint between two monitoring devices 30A and 30B. Monitoring devices 30A and 30B arranged in this manner have substantially the same distance from the control device 40 in a plan view. However, each monitoring device 30A and 30B has an event management unit 352. Therefore, even if each monitoring device 30A and 30B performs an announcement operation upon startup, radio wave interference can be suppressed. This also applies to the positional relationship between monitoring devices 30C and 30D, between monitoring devices 30E and 30F, and between monitoring devices 30G and 30H.

[0133] In this embodiment, the event management unit 352 adds a delay amount DLY, which is a random value calculated based on ID, to a predetermined period INT, which is a common value for each wireless IC 35, to set the random generation period of the announcement event. However, the method of randomly setting the generation period of the announcement event is not limited to the example described above. For example, the generation period of the announcement event can be randomly set solely by the delay amount DLY described above.

[0134] (Second Embodiment)

[0135] The second embodiment is a modification of the foregoing embodiment used as the basic configuration, and can be combined with the description of the foregoing embodiment. In the foregoing embodiment, the generation period of the notification event is set by a random number. Instead of the above, the time of the first notification event after startup can be varied.

[0136] Figure 11 This is a flowchart of the process performed by the event management unit 352 during the connection establishment process in the battery management system 60 according to this embodiment.

[0137] like Figure 11 As shown, the event management unit 352 of the wireless IC 35 sets the waiting time until the generation of the first announcement event and the period of the announcement event (step S200). The waiting time is the time from the reference timing based on the startup time of the wireless IC 35 with the event management unit 352 to the generation time of the first announcement event. For each wireless IC 35, the waiting time is preset to a different value from each other. The period is a fixed value (constant value), that is, not a variable value as in the previous embodiments. The reference timing can be the startup time, or it can be a startup time with a predetermined value added (i.e., a fixed value). The predetermined value is a value common to multiple wireless ICs 35. The event management unit 352 reads and sets the waiting time and period pre-stored in the memory.

[0138] Next, the event management unit 352 generates a notification event according to the waiting time and period set in step S200 (step S210). The event management unit 352 generates a first notification event after a predetermined waiting time has elapsed from the reference time. The event management unit 352 generates a second and subsequent notification events at the aforementioned predetermined period. The wireless IC 35 sends a notification packet in response to the notification event.

[0139] Next, the event management unit 352 determines whether a connection request has been received from the control device 40 (step S220). When the event management unit 352 receives a connection request within the period set in step S200, the event management unit 352 stops generating notification events (step S230) and ends a series of processes.

[0140] On the other hand, if no connection request is received within the period set in step S200, the event management unit 352 will re-execute the processing of step S210 when the period set in step S200 has elapsed. That is, when the period set in step S200 has elapsed, the event management unit 352 will generate a new notification event.

[0141] In the event management process described above, the processing of steps S220 and S230 can be combined with the continuation determination and stop processing of the notification operation by the wireless IC 35. In the battery management system 60, the configuration, except for the processing performed by the event management unit 352, is the same as that described in the preceding embodiments. For example, the positional relationship between the control device 40 and the plurality of monitoring devices 30 is also the same.

[0142] <Summary of the Second Embodiment>

[0143] Figure 12 This is a diagram showing the timing of the notification operations of the two monitoring devices 30 in the battery management system 60 of this embodiment. Figure 12 In the diagram, monitoring devices 30A and 30B are shown as two monitoring devices 30. Furthermore, monitoring device 30A is referred to as SBM30A, and monitoring device 30B is referred to as SBM30B. Figure 12 In this context, the reference time is denoted by ST, and the waiting time from the reference time ST to the generation time of the first notification event after startup is denoted by WT. The generation cycle of the notification event, i.e., the cycle of the notification operation, is denoted by T0.

[0144] The startup time of the wireless IC 35 of monitoring device 30A and the startup time of the wireless IC 35 of monitoring device 30B are approximately the same as described above. Therefore, the reference time ST is also approximately the same for both. The waiting time WT1 of monitoring device 30A and the waiting time WT2 of monitoring device 30B are different from each other. Due to the difference between the waiting times WT1 and WT2, the generation time of the first notification event after startup deviates between the two devices 30A and 30B. The period T0 is a fixed value (i.e., a constant value) and is a common value for monitoring devices 30A and 30B. Each wireless IC 35 generates a notification event within the common period T0. Due to the difference between the waiting times WT1 and WT2, the generation times of the second and subsequent notification events are different (i.e., vary between the two devices). Therefore, it is possible to prevent the periodic overlap of the notification operations of monitoring devices 30A and 30B. Even if monitoring devices 30A and 30B send notification packets at startup, radio wave interference is not possible.

[0145] As described above, in the battery management system 60 of this embodiment, the event management unit 352 manages the generation cycle of notification events, enabling notification operations to be performed at different times. Specifically, the generation cycle of notification events is set such that the generation time of the first notification event differs from each other based on (i.e., with reference to) the startup of each wireless IC 35. Therefore, even if multiple monitoring devices 30 perform notification operations at startup, radio wave interference can be suppressed. In this embodiment, since the cycle itself is fixed, the control device 40 can easily determine how long (i.e., how many cycles) is needed to complete the connection establishment of multiple monitoring devices 30. This improves the controllability of the control device 40.

[0146] In this embodiment, wireless communication, i.e., one-to-many wireless communication, between a control device 40 and multiple monitoring devices 30 occurs within an enclosed space. Each of the multiple monitoring devices 30 has an event management unit 352. In the multiple monitoring devices 30, the event management unit 352 sets the generation cycle of notification events, such that the generation times of the first notification events are different from each other. Therefore, even if the multiple monitoring devices 30 perform notification operations upon startup, radio wave interference can be suppressed. Although in Figure 12 Two monitoring devices 30A and 30B are shown. Similarly, the generation time of the notification event (i.e. the time of the notification operation) can also be different for multiple monitoring devices 30A to 30H.

[0147] (Third Embodiment)

[0148] The third embodiment is a modification of the foregoing embodiments used as the basic configuration, and can be combined with the description of the foregoing embodiments. In the foregoing embodiments, the announcement event at startup has been described. In this embodiment, the announcement event at reconnection is described.

[0149] Figure 13 It is a graph showing the data transmission and reception times of the control device 40, in order to explain reconnection after disconnection. Figure 13 The example illustrates wireless communication with three monitoring devices 30 (30A, 30B, 30C). Tx represents the transmission time of request data sent from control device 40 to monitoring device 30. Rx represents the reception time of response data sent from monitoring device 30 to control device 40. The end of Rx (i.e., the appended character) indicates which monitoring device 30 sent the response data. For example, RxA represents the response data sent from monitoring device 30A.

[0150] When the connection between the control device 40 and a monitoring device 30 is lost, the control device 40 reconnects to the disconnected monitoring device 30 (establishes a connection) while continuing communication with the remaining monitoring devices 30 with which connections have already been established. For example, the disconnection may occur due to a deterioration in the communication environment. Figure 13 In the example shown, the connection between control device 40 and monitoring device 30B is disconnected. Control device 40 continues to connect with the remaining monitoring devices 30. Specifically, data is sent to and received from monitoring device 30C. Then, when communication with the three monitoring devices 30 is complete (successfully or unsuccessfully), control device 40 performs a scan operation to reconnect with monitoring device 30B. Furthermore, monitoring device 30B performs an announcement operation. In this way, the connection between control device 40 and monitoring device 30B is re-established. When the reconnection process is complete, data transmission / reception with the three monitoring devices 30 is performed in a predetermined order.

[0151] Figure 14 This is a flowchart of the process performed by the event management unit 352 during the connection establishment process in the battery management system 60 according to this embodiment.

[0152] First, the event management unit 352 generates a notification event as in step S100 (step S300). Next, the event management unit 352 determines whether it is during startup (step S310). That is, it determines whether the connection was established at startup or during reconnection.

[0153] When it is determined that the connection is at startup, the event management unit 352 randomly sets the generation period of the notification event as in the process of step S120 (step S320). For example, as in the aforementioned embodiment, the generation period is randomly set by adding a delay amount (DLY) as a random number calculated by a specific function to a predetermined period (INT).

[0154] On the other hand, if it is determined that the event is not during startup, i.e. during reconnection, the event management unit 352 sets a period shorter than the period set in step S320 (step S330). For example, a predetermined period (INT) is set as the generation period. Since no delay is added, it is shorter than the period set in step S320.

[0155] Next, as in step S120, the event management unit 352 determines whether a connection request has been received from the control device 40 (step S340). When the event management unit 352 receives a connection request within the period set in step S320 or step S330, the event management unit 352 stops generating notification events (step S350) and ends a series of processes, as in step S130.

[0156] On the other hand, if no connection request is received within the period set in step S320 or step S330, the event management unit 352 will re-execute the processing after step S300 when the set period has elapsed. That is, when the set period has elapsed, the event management unit 352 will generate a new notification event.

[0157] In the above event management process, the processes in steps S340 and S350 can be combined with the continuation determination and stop processing of the announcement operation by the wireless IC 35. The processes in steps S310, S320, and S330, i.e., the start determination process and the period setting process, can be executed before the announcement event generation process (step S300), or these two processes can be executed in parallel. In the battery management system 60, the configuration other than the processes performed by the event management unit 352 is the same as the configuration described in the foregoing embodiments.

[0158] <Summary of the Third Embodiment>

[0159] When the connection between one of the multiple monitoring devices 30 and the control device 40 is lost, the wireless communication between the remaining monitoring devices 30 and the control device 40 continues (i.e., remains). That is, only one disconnected monitoring device 30 performs an announcement operation to re-establish the connection. Therefore, the announcement operations of the multiple wireless ICs 35 do not overlap, thus preventing radio wave interference. Furthermore, the frequency bands used for sending and receiving request and response data are different from the frequency bands used for announcement and scanning operations. Therefore, even if the wireless IC 35 of the disconnected monitoring device 30 performs an announcement operation to re-establish the connection, it is impossible or impossible to interfere with other radio waves during data communication.

[0160] In this embodiment, when the wireless communication connection between one of the multiple monitoring devices 30 and the control device 40 is disconnected and then reconnected, the event management unit 352 of the monitoring device 30 that establishes the connection is set to an event generation period shorter than the start-up period. For example... Figure 15 As shown, at startup, the generation period is randomly set by adding a delay amount (DLY) to the predetermined period (INT), which is a random number calculated by a specific function. Upon reconnection, the predetermined period (INT) is set as the generation period. Therefore, the generation period for notification events is shorter upon reconnection than at startup. That is, notification events occur earlier upon reconnection than at startup. More notification events occur during the predetermined period, thus more notification operations are performed.

[0161] As described above, the possibility of radio wave interference is very low during reconnection, even if an announcement operation is performed. Therefore, the generation cycle of the announcement event can be shortened, and the reconnection time can be shortened compared to the startup time. In this way, delays in another monitoring device 30 that continues data communication, such as delays in the control device 40 acquiring battery information (i.e., monitoring data), can be suppressed. According to this embodiment, the reconnection time can be shortened while suppressing radio wave interference during startup.

[0162] The generation cycle of notification events is not limited to the examples above. For example, in the examples above, the reconnection cycle can be shorter than the predetermined cycle (INT). Furthermore, in the configuration shown in the second embodiment (see...), Figure 11 and 12 The generation cycle during reconnection can be shorter than the generation cycle T0 during startup. Furthermore, the waiting time can be shorter than the waiting time WT during startup.

[0163] (Fourth Embodiment)

[0164] This embodiment is a modification of the foregoing embodiments used as the basic configuration, and can be combined with the description of the foregoing embodiments. Although not specifically mentioned in the foregoing embodiments, the cessation of notification or scanning operations can be determined based on identification information. That is, the target of establishing a connection can be limited.

[0165] Figure 16 This is a flowchart showing the notification process performed by each wireless IC 35 when establishing a connection in the battery management system 60 according to this embodiment. This notification process excludes the event management process performed by the event management unit 352 from the process performed by the wireless IC 35 when establishing a connection. Figure 17 This is a flowchart showing the scanning process performed by the control device 40 when a connection is established in the battery management system 60 according to this embodiment.

[0166] The control device 40 has pre-existing identification information for each of the plurality of monitoring devices 30 (i.e., wireless ICs 35) to be connected. Each of the wireless ICs 35 of the plurality of monitoring devices 30 has identification information for the control device 40 (i.e., wireless IC 44) to be connected. The identification information is, for example, an ID assigned to each device.

[0167] like Figure 16 As shown, the wireless IC 35 of the monitoring device 30 first performs an announcement operation (step S400). The wireless IC 35 performs the announcement operation based on the announcement event generated by the event management unit 352. The wireless IC 35 performs the announcement operation periodically.

[0168] When the wireless IC 35 receives a connection request (step S410), it determines whether it has already connected to all connection targets, that is, whether it has reached the predetermined number of connections (step S420). The wireless IC 35 determines whether all connection targets have been connected by comparing the identification information of the connection targets held by the wireless IC 35 with the identification information included in the connection request data.

[0169] When multiple connection targets exist, if connections to all targets are not completed, the process returns to step S400. When connections to all targets are completed, the process proceeds to step S430. For example, when the connection target is a control device 40, if a connection request is received in step S410, the subsequent confirmation process in step S420 is also "yes".

[0170] Once connections with all connected targets are complete, the wireless IC 35 stops the announcement operation (step S430) and ends a series of processes.

[0171] like Figure 17 As shown, the control device 40 (i.e., the wireless IC 44) first performs a scanning operation (step S500).

[0172] When the control device 40 receives a notification packet, indicating that a connection target has been detected (step S510), the control device 40 sends a connection request to the detected connection target (step S520). Furthermore, the control device 40 determines whether all connection targets have been connected, i.e., whether a predetermined number of connections has been reached (step S530). The control device 40 determines whether all connection targets have been connected by comparing the identification information of the connection targets held by the control device 40 with the identification information contained in the notification packet. If connections with all connection targets have not been completed, the process returns to step S400.

[0173] When connections with all connected targets are completed, the control device 40 stops the scanning operation (step S540) and ends a series of processes.

[0174] After the connection is established, if the communication environment deteriorates due to noise or other factors during data communication and data cannot be sent / received for a certain period of time, the wireless IC 35 of the monitoring device 30 will execute again. Figure 16 The process is shown, and the control device 40 performs it again. Figure 17 The process is as shown. For example, if monitoring data containing battery information cannot be transmitted for a certain period of time, the wireless IC 35 performs the above-mentioned notification operation again. When the control device 40 cannot receive monitoring data containing battery information for a certain period of time, the control device 40 re-executes the above-mentioned notification operation.

[0175] In the battery management system 60, apart from the notification processing performed by the monitoring device 30 and the scanning processing performed by the control device 40, the configuration is the same as that described in the foregoing embodiments.

[0176] <Summary of the Fourth Embodiment>

[0177] As described above, in this embodiment, the monitoring device 30 has pre-existing identification information of the control devices 40 to be connected, and stops the notification operation when a connection is established with all control devices 40 that have the identification information (i.e., a connection is established with all connection targets). In this way, erroneous connections can be suppressed. For example, it is possible to suppress the establishment of connections with the control devices of another vehicle (e.g., the same model) located around the vehicle 10.

[0178] Similarly, the control device 40 has pre-existing identification information for the monitoring devices 30 to be connected, and the scanning operation stops when a connection is established with all monitoring devices 30 that have the identification information (i.e., all connection targets). In this way, erroneous connections can be suppressed. For example, it is possible to suppress the establishment of connections with monitoring devices of another vehicle (e.g., of the same model) present around the vehicle 10.

[0179] The configuration described in this embodiment can be combined with any of the configurations described in the preceding embodiments.

[0180] (Other embodiments)

[0181] This disclosure in this specification and accompanying drawings is not limited to exemplary embodiments. This disclosure includes illustrative embodiments and variations thereof made by those skilled in the art. For example, this disclosure is not limited to the combinations of parts and / or elements shown in the embodiments. The disclosed combinations can be implemented in a variety of combinations. The disclosed combinations may have additional parts / parts that can be added to the embodiments. This disclosure includes those parts and / or elements of the embodiments that are omitted. This disclosure includes the reassignment or combination of parts and / or elements between one embodiment and another. The scope of the disclosed technology is not limited to the description of these embodiments. It should be understood that some of the scope of the disclosed technology (i) is represented by the description of the claims, and (ii) includes all modifications within the equivalent meaning and scope of the claims.

[0182] The present disclosure in the specification, drawings, etc., is not limited to the description in the claims. The present disclosure in the specification, drawings, etc., includes the technical ideas described in the claims, and further extends to variations beyond those described in the claims. Therefore, various technical ideas can be extracted from the present disclosure in the specification, drawings, etc., and are not limited to the description in the claims.

[0183] When an element or layer is described as “arranged above” or “connected”, the element or layer may be directly arranged above or connected to another element or layer, or an intermediate element or layer may exist between them. Conversely, when an element or layer is described as “directly arranged above” or “directly connected”, there is no intermediate element or layer. Other terms used to describe relationships between elements (e.g., “between” vs. “directly between”, and “adjacent” vs. “directly adjacent”) should be interpreted similarly. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. For example, the term A and / or B includes only A, only B, or both A and B.

[0184] Spatial terms such as “inside,” “outside,” “back,” “bottom,” “low,” “top,” and “high” are used herein to facilitate the description of the relationship between one element or feature and another. In addition to the orientations depicted in the accompanying drawings, spatial terms can be intended to encompass different orientations of the device in use or operation. For example, when the device in the accompanying drawings is flipped, an element described as being “below” or “directly below” another element or feature points “above” another element or feature. Therefore, the term “below” can include both above and below. The device may be oriented in another direction (i.e., rotated 90 degrees or in any other direction), and the spatial terms used herein are interpreted accordingly.

[0185] Examples of means and / or functions provided by a microcomputer or IC have been shown, but this disclosure is not limited thereto. It can be implemented by a dedicated computer using a processor programmed to perform one or more functions embodied by a computer program. Alternatively, it can be implemented using dedicated hardware logic circuitry. Furthermore, it can be implemented by combining a processor executing a computer program with one or more hardware logic circuits to form one or more dedicated computers. The computer program can also be stored as instructions to be executed by a computer in a computer-readable, non-transitory, tangible recording medium. Means and / or functions can be provided by software recorded in a substantial storage device and a computer executing such software, software only, hardware only, or a combination thereof. For example, some or all of the functions provided by the processor can be implemented as hardware. Modes of implementing a function as hardware include using one or more ICs. The processor can be implemented by using an MPU, GPU, or DFP instead of a CPU. The processor can be implemented by combining multiple types of arithmetic processing units such as CPUs, MPUs, and GPUs. The processor can be implemented as a system-on-a-chip (SoC). Furthermore, various processing units can be implemented using FPGAs or ASICs. Various programs can be stored in a non-transitory, substantial recording medium. DFP stands for Data Flow Processor, which can use various storage media such as HDD, SSD, flash memory, and SD card as program storage media. SoC stands for System on Chip. FPGA stands for Field Programmable Gate Array. ASIC stands for Application Specific Integrated Circuit. HDD stands for Hard Disk Drive. SSD stands for Solid State Drive. SD stands for Secure Digital.

[0186] For example, an example has been shown where the monitoring device 30 includes a microcomputer 34, but this disclosure is not limited to the above. Figure 18 As shown, a battery management system 60 with a monitoring device 30 but excluding a microcomputer 34 can be used. Figure 18 Corresponding to Figure 14 In this configuration, the wireless IC 35 sends data to / receives data from the monitoring IC 33. The wireless IC 35 can perform sensing using the monitoring IC 33 and a self-diagnostic schedule control, or the main microcomputer of the control unit 40 can perform the same operation.

[0187] The arrangement and number of the battery stack 21 and battery cells 22 constituting the assembled battery 20 are not limited to the examples described above. The arrangement of the monitoring device 30 and / or control device 40 in the battery pack 11 is also not limited to the examples described above.

[0188] For example, in Figure 19 In the example shown, two battery stacks 21 are arranged side-by-side in the Y direction to form a pair. Then, the stack rows of the paired battery stacks 21 are arranged side-by-side in the X direction. Figure 19 In this configuration, battery pack 11 has eight rows. A monitoring device 30 is disposed in each battery pack 21. The monitoring device 30 is disposed on a side surface of the battery pack 21 in the Y direction, which is opposite to the facing surface of the paired battery packs 21. A control device 40 is substantially arranged at the center of the plurality of rows in the X direction. The control device 40 is substantially arranged at the center of the paired battery packs 21 in the Y direction.

[0189] In the plan view, four monitoring devices 30 are arranged at different positions on the circumference of a virtual circle centered on the control device 40. Figure 19 For simplicity, only a virtual circle is shown, but the virtual circles are concentric, and four monitoring devices 30 are arranged on the circumference of each circle. Furthermore, in the plan view, two monitoring devices 30 are arranged symmetrically with respect to the virtual straight line IL1 passing through the control device 40. Similarly, two monitoring devices 30 are arranged symmetrically with respect to the virtual straight line IL2 passing through the control device 40. Straight line IL1 is approximately parallel to the Y-direction, and straight line IL2 is approximately parallel to the X-direction. Additionally, in the plan view, the control device 40 is positioned at the midpoint between the two monitoring devices 30.

[0190] An example of arranging a monitoring device 30 for each battery stack 21 has been shown, but this disclosure is not limited to the above. For example, one monitoring device 30 may be arranged for multiple battery stacks 21. Multiple monitoring devices 30 may be arranged for one battery stack 21.

[0191] An example of a battery pack 11 including a control device 40 is shown, but this disclosure is not limited to the above. Multiple control devices 40 may be provided. That is, the battery pack 11 may include one or more control devices 40. The battery management system 60 may include multiple sets of wireless communication systems constructed between a control device 40 and multiple monitoring devices 30.

[0192] An example of a monitoring device 30 including a monitoring IC 33 is shown, but this disclosure is not limited to the above. Multiple monitoring ICs 33 may be provided. In this case, a wireless IC 35 may be provided for each monitoring IC 33, or a wireless IC 35 may be provided for multiple monitoring ICs 33.

[0193] Although all monitoring devices 30 that perform wireless communication with control device 40 in the above example have an event management unit 352, for example, only two monitoring devices 30 may have an event management unit 352. In two monitoring devices 30 each having an event management unit 352, the occurrence of radio wave interference at startup can be suppressed. That is, two or more monitoring devices 30 may have an event management unit 352. Since the event management unit 352 manages the generation cycle of notification events to perform notification operations at different times, radio wave interference at startup can be suppressed in two or more monitoring devices 30 having an event management unit 352.

[0194] The monitoring IC 33 is also known as the "monitor cell supervisor".

[0195] The microcomputer 34 is also known as a "monitor computer".

[0196] Wireless circuit unit 35 is also called a “monitor transceiver”.

Claims

1. A battery management system, comprising: Monitoring devices (30) are arranged in a housing (50) for accommodating batteries, wherein each monitoring device includes: (i) A monitoring circuit (33) capable of acquiring battery information representing the state of batteries (20, 21, 22), and (ii) a monitor transceiver (35) capable of performing wireless communication by sending data to and receiving data from the monitoring circuit; and A control device (40), arranged in the housing, performs predetermined processing based on the battery information by wirelessly communicating with various monitor transceivers in the monitoring device, wherein When the monitoring device is activated, each monitor transceiver performs an announcement operation during a periodic announcement event to establish a wireless communication connection between the monitoring device and the control device, and the control device performs a scanning operation. Each of the two or more monitoring devices has its own event management unit (352) that manages the generation cycle of the notification events so that the notification operation can be performed at different times.

2. The battery management system as described in claim 1, wherein... The event management unit sets the generation cycle of the notification event using random numbers.

3. The battery management system as described in claim 1, wherein... The event management unit sets the generation cycle of the notification event, such that the generation time of the first notification event after startup is different for each of the monitor transceivers.

4. The battery management system as described in any one of claims 1-3, wherein The monitoring device, which has the event management unit, is arranged at different positions on the circumference of a virtual circle centered on the control device.

5. The battery management system as described in claim 4, wherein... The virtual circle includes concentric circles, and The two or more monitoring devices having the event management unit are arranged on the circumference of each of the concentric circles.

6. The battery management system as described in any one of claims 1-3, wherein The monitoring device having the event management unit includes a first monitoring device and a second monitoring device, and The control device is located at the midpoint between the first monitoring device and the second monitoring device.

7. The battery management system as described in any one of claims 1-3, wherein The monitoring device having the event management unit includes a third monitoring device and a fourth monitoring device, and The third and fourth monitoring devices are arranged symmetrically with respect to a virtual straight line passing through the control device.

8. The battery management system as described in any one of claims 1 to 3, wherein After the wireless communication connection between one of the monitoring devices having the event management unit and the control device is lost, the event management unit of the monitoring device that re-establishes the connection sets the generation cycle of the notification event to a shorter cycle than the generation cycle of the notification event at startup.

9. The battery management system as described in any one of claims 1 to 3, wherein The monitoring device has pre-existing identification information for the control devices to be connected, and when a connection is established with all the control devices that have the identification information, the notification operation is stopped. The control device has pre-existing identification information for the monitoring devices to be connected, and stops the scanning operation when a connection is established with all the monitoring devices that have the identification information.

10. A battery management system, comprising: The first monitoring device (30A) includes: (i) First processor (33, 34, 35), (ii) a first non-transitory computer-readable storage medium (33, 34, 35), and (iii) First antenna (37); The second monitoring device (30B) includes: (i) Second processors (33, 34, 35), (ii) a second non-transitory computer-readable storage medium (33, 34, 35), and (iii) The second line (37); and Control device (40), comprising: (i) Control processors (44, 45, 46), (ii) Control of non-transitory computer-readable storage media (44, 45, 46), and (iii) Control antenna (42).

11. The battery management system of claim 10, wherein the battery management system is configured as follows: (a1) The scanning operation is performed by the control device (S11). (b1) The first monitoring device performs a first notification operation (S12), the first notification operation including sending a first notification packet, the first notification packet including first identification information associated with the first monitoring device. (c1) The first notification packet is detected by the control device (S13). (d1) The control device sends a first connection request to the first monitoring device. (e1) Establish a first connection between the control device and the first monitoring device (S14), and (f1) The first monitoring device stops the first notification operation. (a2) The control device continues to perform the scanning operation (S11). (b2) The second monitoring device performs a second notification operation (S12), the second notification operation including sending a second notification packet, the second notification packet including second identification information associated with the second monitoring device. (c2) The control device detects the second notification packet (S13). (d2) The control device sends a second connection request to the second monitoring device. (e2) Establish a second connection between the control device and the second monitoring device (S14), and (f2) The second notification operation is stopped by the second monitoring device.

12. The battery management system of claim 10, wherein the first monitoring device is configured to perform a first event management process during the first notification operation, and wherein the first event management process includes: (i) Generate a first notification event, the first notification event including sending a first notification packet (S100); (ii) Using a first pseudo-random generator, a first delay amount (DLY) is pseudo-randomly generated for the first monitoring device (S110); (iii) Determine that the first generation period (T1) is equal to the sum of the predetermined period (INT) and the first delay amount (DLY) of the first monitoring device, wherein the predetermined period is greater than the event time (EVT) required to generate the first notification event; and (iv) Determine whether a connection request was received before the first generation cycle terminates (S120 = ?).

13. The battery management system of claim 12, wherein the first event management process further includes: (v) Determine that the connection request was received before the first generation cycle terminates (S120 = Yes); as well as (vi) Stop generating the first notification event (S130).

14. The battery management system of claim 12, wherein the first event management process further includes: (v) Determine that no connection request was received before the first generation cycle terminates (S120 = No); as well as (vi) Generate a subsequent first notification event, the subsequent first notification event including sending a subsequent notification packet (S100); (vii) Using a first pseudo-random generator, a subsequent first delay amount (DLY) is generated pseudo-randomly for the first monitoring device, wherein the subsequent first delay amount may not be equal to the first delay amount (S110); (viii) Determine that the subsequent first generation cycle (T2) is equal to the sum of the predetermined cycle (INT) and the subsequent delay amount (DLY); as well as (ix) Determine whether the connection request was received before the termination of the subsequent first generation cycle (S120).

15. The battery management system of claim 10, wherein the first monitoring device is configured as: After the start event, wait until the first wait time (WT1) has elapsed, then execute the first notification event; and After the first waiting time has elapsed, wait until a fixed period of time (T0) has elapsed, and then execute the subsequent first notification event.

16. The battery management system of claim 15, wherein the second monitoring device is configured as: After the start event, wait until the second wait time (WT2) has elapsed, then execute the second notification event; and After the second waiting time has elapsed, wait until the fixed periodic time has elapsed, and then execute the subsequent second notification event.

17. The battery management system of claim 16, wherein The difference between the second waiting time and the first waiting time is greater than the time required to execute the first notification event, and The first waiting time and the second waiting time are predetermined and are provided to the first monitoring device and the second monitoring device respectively in the setting process.

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