Management system with supervisory control for rechargeable energy storage device in electric vehicle
11225169 · 2022-01-18
Assignee
Inventors
- Yue-Yun Wang (Troy, MI)
- Lei Hao (Troy, MI)
- Brian J. Koch (Berkley, MI, US)
- Jeffrey S. Piasecki (Rochester, MI, US)
- Garrett M. Seeman (Novi, MI, US)
Cpc classification
Y02T90/16
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H02J7/0014
ELECTRICITY
B60L58/12
PERFORMING OPERATIONS; TRANSPORTING
Y04S30/12
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60L53/68
PERFORMING OPERATIONS; TRANSPORTING
B60L58/22
PERFORMING OPERATIONS; TRANSPORTING
B60L58/13
PERFORMING OPERATIONS; TRANSPORTING
Y02T10/70
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60R16/0231
PERFORMING OPERATIONS; TRANSPORTING
Y02E60/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H02J7/00047
ELECTRICITY
Y02T90/12
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60L50/64
PERFORMING OPERATIONS; TRANSPORTING
Y02T90/167
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y02T10/7072
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
H02J7/00
ELECTRICITY
B60R16/023
PERFORMING OPERATIONS; TRANSPORTING
B60L58/12
PERFORMING OPERATIONS; TRANSPORTING
B60L58/22
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Management system for a rechargeable energy storage device in an electric vehicle and corresponding method is disclosed. The rechargeable energy storage device has one or more battery packs each having a plurality of modules with one or more respective cells. A respective module management unit is embedded in each of the plurality of modules through respective microcircuits and configured to determine one or more local parameters. A supervisory controller is configured for two-way communication with the respective module management unit. The supervisory controller is configured to receive the local parameters, determine one or more global pack parameters based in part on the local parameters and transmit the global pack parameters back to the respective management unit. The supervisory controller is configured to control operation of the rechargeable energy storage device based in part on the global pack parameters and the local parameters.
Claims
1. A management system for an electric vehicle, the management system comprising: a rechargeable energy storage device having one or more battery packs, the one or more battery packs respectively having a plurality of modules with one or more respective cells; respective module management units embedded in each of the plurality of modules through respective microcircuits, the respective module management units being configured to determine one or more local parameters; a supervisory controller configured to engage in two-way communications with the respective module management units; wherein the supervisory controller is configured to receive the one or more local parameters, determine one or more global pack parameters based in part on the one or more local parameters and transmit the one or more global pack parameters to the respective module management units; and wherein the supervisory controller is configured to control operation of the rechargeable energy storage device based in part on the one or more global pack parameters.
2. The management system of claim 1, further comprising: a pack communicator configured to interface wirelessly with the respective module management units for respective data transmission; and wherein the pack communicator is directly connected to the supervisory controller via at least one communication BUS.
3. The management system of claim 1, wherein the one or more battery packs include a first battery pack and a second battery pack and further comprising: a first pack communicator configured to interface wirelessly with the respective module management units in the first battery pack, the first pack communicator being connected to the supervisory controller via a first communication BUS; and a second pack communicator configured to interface wirelessly with the respective module management units in the second battery pack, the second pack communicator being connected to the supervisory controller via a second communication BUS.
4. The management system of claim 1, wherein the one or more battery packs include a first battery pack and a second battery pack and further comprising: a shared communication BUS configured to enable direct communication between the supervisory controller, the respective module management units in the first battery pack and the respective module management units in the second battery pack.
5. The management system of claim 1, further comprising: at least two pack sensors configured to respectively measure and transmit a pack voltage and a pack current of the one or more battery packs to the supervisory controller; a fault detection module selectively executable by the supervisory controller; wherein the respective module management units are configured to determine respective module voltages and communicate the respective module voltages to the supervisory controller, the supervisory controller being configured to calculate a sum of the respective module voltages; and wherein the supervisory controller is configured to, when a difference between the sum of the respective module voltages and the pack voltage is above a predetermined threshold, determine whether an irregularity exists in the pack voltage via the fault detection module.
6. The management system of claim 5, wherein: the supervisory controller is configured to, when the difference between the sum of the respective module voltages and the pack voltage is above the predetermined threshold and the irregularity is in the pack voltage, reset a value of the pack voltage as the sum of the respective module voltages.
7. The management system of claim 6, wherein: when the difference between the sum of the respective module voltages and the pack voltage is above the predetermined threshold and the irregularity is not in the pack voltage, the supervisory controller is configured to at least one of transmit an alert and derate a respective power rating of the one or more battery packs.
8. The management system of claim 1, wherein: the one or more local parameters include an array of cell voltages, a respective cell state of charge, a respective cell state of health, an allowable module voltage limit, an allowable module temperature limit and an allowable module current limit; and the one or more global pack parameters include a power estimation for the one or more battery packs and a cell balancing target.
9. The management system of claim 1, wherein: the one or more local parameters include a respective cell state of charge, a respective cell state of health when at least one of the respective cells meets a predefined weak cell threshold, an allowable module voltage limit and an allowable module current limit; the one or more global pack parameters include a pack state of charge, a pack capacity and a weak cell state of health monitoring function; and the weak cell state of health monitoring function is configured to estimate an amount of energy remaining in the at least one battery pack.
10. The management system of claim 1, wherein: the one or more local parameters include respective current limits (I.sub.mi) for the plurality of modules, i being a module index and n being a quantity of the plurality of modules in each of the one or more battery packs; the one or more global pack parameters include an allowable pack current limit (I.sub.pL) determined as a minimum of respective current limits [I.sub.pL=min (I.sub.m1, I.sub.m2, . . . I.sub.mn)]; and the supervisory controller is configured to determine or predict a total power (P.sub.wp) at one or more time horizons for the one or more battery packs as a summation of respective module powers (P.sub.mi) such that [P.sub.wp=P.sub.m1+P.sub.m2+ . . . P.sub.mn], the respective module powers (P.sub.mi) being determined by the respective module management units based on the pack current limit.
11. The management system of claim 1, wherein: the one or more local parameters include a respective module maximum state of charge (SOC(M.sub.i)_max=max(SOC(C.sub.j), j=1,2 . . . k), with i being a module index and k being a quantity of the respective cells; the one or more local parameters include a respective module minimum state of charge (SOC(M.sub.i)_min=min(SOC(C.sub.j)), j=1,2 . . . k); the one or more global pack parameters include a pack maximum state of charge (SOC.sub.max=max (SOC(M.sub.i)_max),),i=1,2 . . . n), n being a quantity of the respective modules, a pack minimum state of charge (SOC.sub.min=min (SOC(M.sub.i)_min), i=1,2 . . . n), and a targeted pack state of charge for the at least one battery pack; and the targeted pack state of charge (SOC.sub.target) is determined as:
SOC.sub.target=½(SOC.sub.max−SOC.sub.min).
12. The management system of claim 1, wherein: the plurality of modules includes at least four modules; the one or more local parameters include a module state of charge; and the one or more global pack parameters include a real-time pack state of charge; the real-time pack state of charge is defined as at least one of a minimum module state of charge among the plurality of modules and a moving average of three lowest values of the respective module state of charge, the three lowest values being within a predetermined range.
13. The management system of claim 1, wherein: the plurality of modules includes at least four modules; the one or more local parameters include a respective module capacity; and the one or more global pack parameters include a pack capacity defined as at least one of a minimum module capacity among the plurality of modules and a mean of three lowest values of the respective module capacity, the three lowest values being within a predetermined range.
14. A method of controlling a rechargeable energy storage device having one or more battery packs in an electric vehicle having a supervisory controller with a processor and tangible, non-transitory memory, the method comprising: configuring the one or more battery packs with a plurality of modules each having one or more respective cells; installing respective module management units in each of the plurality of modules through respective microcircuits, the supervisory controller being configured for two-way communication with the respective module management units; determining one or more local parameters and transmitting the one or more local parameters to the supervisory controller, via the respective module management units; receiving the one or more local parameters, determining one or more global pack parameters based in part on the one or more local parameters and transmitting the one or more global pack parameters to the respective module management units, via the supervisory controller; and configuring the supervisory controller to control operation of the rechargeable energy storage device based in part on the one or more global pack parameters.
15. The method of claim 14, wherein the one or more battery packs include a first battery pack and a second battery pack and further comprising: connecting a first pack communicator to the supervisory controller via a first communication BUS and configuring the first pack communicator to interface wirelessly with the respective module management units in the first battery pack; and connecting a second pack communicator to the supervisory controller, via a second communication BUS, and configuring the second pack communicator to interface wirelessly with the respective module management units in the second battery pack.
16. The method of claim 14, wherein the one or more battery packs include a first battery pack and a second battery pack and further comprising: facilitating direct communication between the supervisory controller, the respective module management units in the first battery pack and the respective module management units in the second battery pack via a shared communication BUS.
17. The method of claim 14, further comprising: obtaining a pack voltage and a pack current of the one or more battery packs, via at least two pack sensors respectively; determining respective module voltages based on voltages of the respective cells and communicating the respective module voltages to the supervisory controller, via the respective module management units; calculating a sum of the respective module voltages, via the supervisory controller; and determining whether an irregularity exists in the pack voltage, via a fault detection module in the supervisory controller, when a difference between the sum of the respective module voltages and the pack voltage is above a predetermined threshold.
18. The method of claim 17, further comprising: resetting a value of the pack voltage as the sum of the respective module voltages, when the difference between the sum of the respective module voltages and the pack voltage is above the predetermined threshold and the irregularity is in the pack voltage; at least one of transmitting an alert and derating a respective power rating of the one or more battery packs, via the supervisory controller, when the difference between the respective module voltage and the pack voltage is above the predetermined threshold and the irregularity is not in the pack voltage.
19. An electric vehicle comprising: a rechargeable energy storage device having one or more battery packs, the one or more battery packs respectively having a plurality of modules with one or more respective cells; respective module management units embedded in each of the plurality of modules through respective microcircuits, the respective module management units being configured to determine one or more local parameters; a supervisory controller configured to engage in two-way communications with the respective module management units; a respective pack communicator configured to interface wirelessly with the respective module management units, the respective pack communicator being connected to the supervisory controller via at least one communication BUS; wherein the supervisory controller is configured to receive the one or more local parameters, determine one or more global pack parameters based in part on the one or more local parameters and transmit the one or more global pack parameters back to the respective module management units; wherein the one or more local parameters include a module state of charge, a module capacity, a respective cell state of charge, a respective cell state of health, an allowable module voltage limit, an allowable module temperature limit and an allowable module current limit; wherein the one or more global pack parameters include a power estimation for the one or more battery packs, a cell balancing target, a pack state of charge, a pack capacity and a weak cell state of health monitoring function; and wherein the supervisory controller is configured to control operation of the rechargeable energy storage device based in part on the one or more global pack parameters.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
DETAILED DESCRIPTION
(5) Referring to the drawings, wherein like reference numbers refer to like components,
(6) Referring to
(7) Referring to
(8) Referring to
(9) Referring to
(10) Referring to
(11) The management system 10 is characterized by a functional partition between the respective management units 30 and the supervisory controller C. In other words, the respective management units 30 and the supervisory controller C may perform mutually exclusive functions. The respective management unit 30 is configured to receive the pack current from the supervisory controller C, and to measure and monitor respective voltages from each of its respective cells 44, as well as the temperature of the module and respective cells 44. The respective management unit 30 may determine one or more local parameters, which may include a respective maximum and minimum module voltages, module state of charge, module capacity, cell state of charge, a respective cell state of health if a weaker cell is detected, an allowable module voltage limit and an allowable module current limit. The supervisory controller C is configured to receive the one or more local parameters, determine one or more global pack parameters based in part on the one or more local parameters and transmit the one or more global pack parameters back to the respective management units 30.
(12) The supervisory controller C is configured to control operation of the rechargeable energy storage device 12 based in part on the one or more global pack parameters. The global pack parameters may include a respective power estimation for the battery pack 14, a cell balancing target, a pack state of charge, a pack capacity and a weak cell state of health monitoring function. The supervisory controller C may flag a weak cell (based on data provided by the respective management unit 30) and follow up or track its state of health via the weak cell state of health monitoring function. The acceptable threshold for defining a “weak” cell may be varied based on the application at hand and may include a predefined minimum capacity. The supervisory controller C may control battery charging current and voltage and time based on one or more global parameters, such as pack voltage, temperature and current limits, and state of health of a weaker cell. Additionally, the global pack parameters may be consumed as data by other controllers in the electric vehicle 15. Referring to
(13) The respective module management unit 30 may be configured to store local parameters, e.g. module manufacture series numbers, module chemistry profile, module state of charge, module capacity, and module and/or associated cell state of health parameters, in their respective microcontroller memory 37. Thus, in the event one of the plurality of modules 20 requires servicing, a diagnostic scan tool or module repair tool may work directly with the respective module management unit 30 for service based on these parameters. A refurbished module may be updated with these parameters through the respective module management unit 30 during a module rebuilt, such that when it is reassembled back into the battery pack 14, it is immediately ready to work with the supervisory controller C without further testing and/or calibration.
(14) Alternate configurations for the rechargeable energy storage device 12 are shown in
(15) Referring to
(16) Referring to
(17) In one example, each of the plurality of modules 20 obtains its respective current limits (I.sub.mi), which may be estimated from the current limits of its respective cells 44, and sends it to the supervisory controller C, which determines an allowable pack current limit (I.sub.pL) as a minimum of the respective current limits [I.sub.pL=min(I.sub.m1, I.sub.m2, . . . I.sub.mn)]. This data is sent back to the plurality of modules 20 and the respective current limits (I.sub.mi) are replaced by the allowable pack current limit (I.sub.pL). In other words, the allowable pack current limit (I.sub.pL) is imposed as a new limit for each of the plurality of modules 20, regardless of the respective current limits (I.sub.mi).
(18) In another example, the respective module management units 30 determine a respective maximum module state of charge(SOC(M.sub.i)_max=max(SOC(C.sub.j), j=1, 2 . . . k) as a maximum state of charge of the respective cells 44, with i being a module index and k being a quantity of the respective cells. The respective module management unit determines a respective module minimum state of charge (SOC(M.sub.i)_min=min(SOC(C)), j=1, 2 . . . k), as a minimum state of charge of the respective cells 44. The global pack parameters may include a pack maximum state of charge (SOC.sub.max=max (SOC(M.sub.i)_max)), a pack minimum state of charge (SOC.sub.min=min (SOC(M.sub.i)_min)), and a targeted pack state of charge for the battery pack 14. The targeted pack state of charge is determined as: SOC.sub.target=½(SOC.sub.max−SOC.sub.min) and is sent back to the respective module management units 30. The respective module management units 30 may be configured to execute cell balancing (for the respective cells in its own module) based on the targeted pack state of charge (SOC.sub.target).
(19) In another example, the respective plurality of modules 20 includes at least four modules. The local parameters may include a respective module state of charge (SOC.sub.Mi) and the global pack parameters may include a real-time pack state of charge defined as the minimum module state of charge among the plurality of modules, or as a moving average of the three lowest values of the respective module state of charge when the three lowest values are within a predetermined range, i.e. none of them is largely deviated from the rest. The local parameters may include a respective module capacity and the global pack parameters may include a pack capacity defined as the minimum module capacity among the plurality of modules, or as a mean of three lowest values of the respective module capacity when the three lowest values are within a predetermined range.
(20) Referring now to
(21) Per block 302 of
(22) When the difference between the sum of the respective module voltages and the pack voltage is above the predetermined threshold, the method 300 proceeds to block 308. Referring to
(23) When an irregularity is in the pack voltage, the method 300 proceeds to block 310, where the supervisory controller C is configured to reset a value of the pack voltage as the sum of the respective module voltages. When the irregularity is not in the pack voltage, the method 300 proceeds to blocks 312 and 314. Per block 312, the supervisory controller C is configured to transmit an alert, for example, to a user of the electric vehicle 15 via a user interface. The supervisory controller C may be configured to transmit an alert to the remote server 52 via the wireless network 42 and/or the mobile application 56. For example, this information may be employed by a fleet supervisor when the electric vehicle 15 is an autonomous vehicle.
(24) Per block 314, the supervisory controller C is configured to derate or reduce a power rating of the battery pack 14. If the total power rating of the rechargeable storage device 12 is sufficiently reduced (i.e. reaches a predefined minimum), the supervisory controller C may be configured to switch to an alternative mode of operation, which may be a limp-home mode or other mode restricting energy consumption and/or speed of the electric vehicle 15.
(25) In summary, the management system 10 provides for focused individual cell monitoring as well as allowing cross-checking for the at least two pack sensors 60, 62. Additionally, the management system 10 allows for a wireless management strategy and reconfigurable system. In other words, removal and replacement of one module does not affect other modules. Accordingly, the management system 10 improves the functioning of the electric vehicle 15.
(26) The flowchart in
(27) The supervisory controller C includes a computer-readable medium (also referred to as a processor-readable medium), including a non-transitory (e.g., tangible) medium that participates in providing data (e.g., instructions) that may be read by a computer (e.g., by a processor of a computer). Such a medium may take many forms, including, but not limited to, non-volatile media and volatile media. Non-volatile media may include, for example, optical or magnetic disks and other persistent memory. Volatile media may include, for example, dynamic random access memory (DRAM), which may constitute a main memory. Such instructions may be transmitted by one or more transmission media, including coaxial cables, copper wire and fiber optics, including the wires that comprise a management system bus coupled to a processor of a computer. Some forms of computer-readable media include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, other magnetic media, a CD-ROM, DVD, other optical media, punch cards, paper tape, other physical media with patterns of holes, a RAM, a PROM, an EPROM, a FLASH-EEPROM, other memory chips or cartridges, or other media from which a computer can read.
(28) Look-up tables, databases, data repositories or other data stores described herein may include various kinds of mechanisms for storing, accessing, and retrieving various kinds of data, including a hierarchical database, a set of files in a file management system, an application database in a proprietary format, a relational database management system (RDBMS), etc. Each such data store may be included within a computing device employing a computer operating management system such as one of those mentioned above and may be accessed via a network in one or more of a variety of manners. A file management system may be accessible from a computer operating management system and may include files stored in various formats. An RDBMS may employ the Structured Query Language (SQL) in addition to a language for creating, storing, editing, and executing stored procedures, such as the PL/SQL language mentioned above.
(29) The detailed description and the drawings or FIGS. are supportive and descriptive of the disclosure, but the scope of the disclosure is defined solely by the claims. While some of the best modes and other embodiments for carrying out the claimed disclosure have been described in detail, various alternative designs and embodiments exist for practicing the disclosure defined in the appended claims. Furthermore, the embodiments shown in the drawings or the characteristics of various embodiments mentioned in the present description are not necessarily to be understood as embodiments independent of each other. Rather, it is possible that each of the characteristics described in one of the examples of an embodiment can be combined with one or a plurality of other desired characteristics from other embodiments, resulting in other embodiments not described in words or by reference to the drawings. Accordingly, such other embodiments fall within the framework of the scope of the appended claims.