Restarting network from power saving mode in WBMS

Abstract

In an example, a wireless battery management system (200) includes one or more sets of battery cells (208). The wireless battery management system (200) includes a master node (102) configured to broadcast a downlink packet in a first superframe. The wireless battery management system (200) also includes a first secondary node (206) coupled to a first set of battery cells (208). The first secondary node (206) is configured to receive the downlink packet and transmit a first uplink packet to the primary node (102) during the first superframe. The wireless battery management system (200) includes a second secondary node (210) coupled to a second set of battery cells (212). The second secondary node (210) is configured to receive the first uplink packet from the first secondary node (206) in the first superframe. The second secondary node (210) is also configured to transmit a second uplink packet to the primary node (102) during a second superframe.

Description

Background Art

[0001] Modern vehicles may contain multiple battery cells. Sensors may monitor information associated with the cells, such as temperature, voltage, and other indicators of cell status and health, for vehicle safety and to ensure proper operation. Summary of the invention

[0002] According to at least one example of the present specification, a wireless battery management system includes one or more groups of battery cells. The wireless battery management system includes a master node configured to broadcast a downlink packet in a first superframe. The wireless battery management system also includes a first node coupled to the first group of battery cells. The first node is configured to receive the downlink packet and transmit a first uplink packet to the master node during the first superframe. The wireless battery management system includes a second node coupled to a second group of battery cells. The second node is configured to receive the first uplink packet from the first node in the first superframe. The second node is also configured to transmit a second uplink packet to the master node during a second superframe.

[0003] According to at least one example of the present specification, a method includes transmitting, in a wireless battery management system, a downlink packet from a primary node to one or more secondary nodes in a first superframe. The method includes receiving the downlink packet at a primary node. The method also includes transmitting a first uplink packet from the primary node to the primary node in the first superframe. The method also includes receiving the first uplink packet at a secondary node in the first superframe. The method includes transmitting a second uplink packet from the secondary node to the primary node during a second superframe.

[0004] According to at least one example of the present specification, a method includes transmitting a first downlink packet from a primary node to one or more secondary nodes in a first superframe. The method also includes receiving the first downlink packet at a first subnode in the first superframe. The method includes failing to receive the first downlink packet at a second subnode in the first superframe. The method also includes transmitting a first uplink packet from the first subnode to the primary node in the first superframe. The method includes transmitting a second downlink packet from the primary node to the one or more secondary nodes in a second superframe. The method includes receiving the second downlink packet at the second subnode in the second superframe. The method also includes transmitting a second uplink packet from the second subnode to the primary node in the second superframe. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1is a block diagram of a wireless battery management system according to various examples.

[0006] Figure 2 is a block diagram of a wireless battery management system according to various examples.

[0007] Figure 3A is a superframe interval that may be used by a wireless battery management system according to various examples.

[0008] Figure 3B is a superframe interval that may be used by a wireless battery management system according to various examples.

[0009] Figure 4A and 4B Continuous superframe intervals that may be used by a wireless battery management system are shown according to various examples.

[0010] Figure 5A is a diagram of scaled power consumption for secondary network nodes according to various examples.

[0011] Figure 5B is a graph of scaled power consumption for a master node according to various examples.

[0012] Figure 6 is a table of approximate power consumption at primary and secondary nodes according to various examples.

[0013] Figure 7 is a flow chart of a method for network restart from power save mode according to various examples.

[0014] Figure 8 is a flow chart of a method for network restart from power save mode according to various examples herein.

[0015] The same reference numbers or other reference designators are used in the drawings to indicate the same or similar features (functionally and / or structurally). DETAILED DESCRIPTION

[0016] Some electronic devices operate using batteries. For example, electric vehicles include multiple battery cells that provide power to these vehicles. Because the battery cells in electronic devices can provide large amounts of power, and further because the power provided by the battery cells can be critical to the operation of the electronic devices, the electronic devices may include systems to manage the battery cells.

[0017] A battery management system (BMS) can manage the battery cells of an electronic device in various ways. For example, a BMS can monitor the health (e.g., voltage, current, temperature) of battery cells in an electronic device. In addition, the BMS can control various battery cells to manage the amount of power provided by the battery cells and direct the power into the electronic device. Typically, a BMS includes multiple components, such as multiple battery modules and a controller to manage the battery modules. Each battery module can, in turn, be coupled to multiple battery cells and include a battery monitor to monitor those battery cells. Thus, the battery cells coupled to the battery modules provide power to the electronic device; the battery monitors in the battery modules monitor the health and operation of the battery cells in the battery modules; and the controller communicates with the battery monitor to ensure that the battery module and its cells are operating correctly. The controller may also communicate with the battery monitor to control the operation of the battery cells so as to connect, disconnect, redirect, or otherwise balance the power provided by those battery cells.

[0018] The BMS may incorporate wireless technology to produce a wireless battery management system (WBMS). For example, a primary network node contains or is coupled to a controller, and a secondary network node contains a battery module that controls a plurality of battery cells. The primary network node and the secondary network node may communicate with each other wirelessly, for example using radio frequency. In some protocols, a superframe may be used to facilitate wireless communication between the primary network node and the secondary network node. In the superframe, the primary network node first broadcasts a downlink (DL) communication (or packet) to a plurality of secondary network nodes. The secondary network nodes individually respond to the primary network node using an uplink (UL) communication (or packet) in a serial manner. Superframes are further described below.

[0019] A WBMS may have certain requirements for reliable operation, such as certain throughput levels, data speeds, packet error rates, power consumption at each device (including the master node), and guarantees of the speed at which sensors or monitors send data collected from battery cells. Some example requirements may include bandwidth of 600 kilobits per second (kbps), data latency of less than 100 milliseconds (ms), and a latency of better than 10 -5 The system provides a packet error rate of 0.001% and power consumption of less than 1 milliamp (mA) at the primary node and less than 300 microamps (μA) at the secondary node.

[0020] Power consumption can be considered during two states: when the vehicle is turned on, and when the vehicle is turned off. If the vehicle is turned on, the vehicle battery or other high voltage battery can power the wireless node. If the vehicle is turned off, the wireless node enters a shutdown mode that consumes less power. However, in one example, after turning the vehicle back on, the wireless node should start up and have the WBMS network operating in less than 300ms, and preferably as fast as possible.

[0021] Wireless nodes in a WBMS network can communicate with each other using time intervals called superframes. Superframes are divided into time slots, which can be further allocated as downlink time slots and uplink time slots. Downlink time slots transmit packets from a master node to a secondary node. Uplink time slots transmit packets from a secondary node to a master node. In some examples, the master node transmits a broadcast packet in a downlink time slot, and the broadcast packet is received by all secondary nodes.

[0022] If the vehicle is turned off and the WBMS is not active, in some instances, a keep alive method may be applicable. During some superframe intervals, no activity will occur. Then, an active keep alive superframe occurs, which may have one downlink and multiple uplinks. After the active keep alive superframe, one or more quiet superframes occur. After the quiet superframe, another active keep alive superframe occurs, and the process repeats as necessary. This method maintains power when the vehicle is turned off.

[0023] If the vehicle is turned off and then turned on, an interrupt is sent to the master node. The interrupt can arrive in an idle superframe or in an active superframe. If the master node is active and may have interrupt information in the downlink packet, it does so and sends the information to each secondary node (e.g., a wake-up signal). The secondary node may then respond. However, if an interrupt occurs during an idle superframe, the secondary node may not be active and listen. Alternatively, the secondary node may be idle and wait for the next active keep-alive superframe. In the scenario, the master node waits for the next active superframe to transmit the wake-up signal. However, for various reasons, such as interference with the wireless signal, the secondary node may not receive the downlink packet during the next active superframe. In the case, the WBMS will have to wait for another active superframe for all secondary nodes to wake up and respond. This scenario increases the time for the network to restart.

[0024] In the examples herein, a first time node that fails to receive an expected downlink packet from a master node during an active superframe can be configured to turn on its receiver to opportunistically listen for other frames to be transmitted from other secondary nodes to the master node during the active superframe. If the first time node receives a transmission from another secondary node, the first time node wakes up and enters an active state. In other examples herein, a first time node that misses a downlink packet from a master node can be configured to use its receiver to listen during the next superframe, rather than listening during the current superframe. If there is any activity in the next superframe, the WBMS is active and the first time node can continue to operate normally.

[0025] Figure 11 is a perspective view of an exemplary system 100, such as a motor vehicle, that includes a WBMS 101. In some examples, system 100 is any system that may include a wireless battery management system to power one or more components of system 100. As shown, WBMS 101 includes a main network node 102 (also referred to herein as a primary node), a battery controller 104, a plurality of secondary network nodes 106, and a plurality of battery cells 108. In one example, WBMS 101 may include a plurality of main network nodes. Although the present disclosure describes communication techniques primarily in the context of wireless systems, these techniques may also be applicable to wired systems (e.g., where the connection between nodes 102 and 106 is wired). Main network nodes may also be referred to herein as primary nodes, and secondary network nodes may also be referred to herein as secondary nodes.

[0026] In one example, the master network node 102 is coupled to the battery controller 104 using a first wired connection 110. In one example, the first wired connection 110 between the master network node 102 and the battery controller 104 is a universal asynchronous receiver / transmitter (UART), an interconnect integrated circuit (I2C), or the like. The secondary network node 106 is wirelessly coupled to the master network node 102 and is coupled to the battery unit 108 using a second wired connection 112.

[0027] In one example, WBMS 101 provides wireless radio frequency (RF) communication between primary network node 102 and secondary network node 106. In one example, the wireless RF communication uses the license-free 2.4 gigahertz (GHz) industrial, scientific and medical (ISM) band from 2.4 GHz to 2.483 GHz, which complies with the Bluetooth Special Interest Group (SIG). In an example, WBMS 101 uses 2 megabits per second (Mbps) Bluetooth low energy (BLE) across the physical layer (PHY). The open system interconnection (OSI) model includes PHY as a layer for transmitting raw bits on a physical medium. In this case, the PHY is free space, and WBMS 101 uses it to communicate wirelessly between primary network node 102 and secondary network node 106. In one example, the transmission power of WBMS 101 is less than or equal to 10 decibel-milliwatts (dBm). Additional exemplary details for establishing a communication channel in a WBMS may be found in commonly assigned U.S. patent application Ser. No. 17 / 233,106, filed on April 16, 2021, entitled “Wireless Protocol for Battery Management,” and U.S. patent application Ser. No. 17 / 399,793, filed on August 11, 2021, entitled “Wireless Battery Management System Setup,” each of which is incorporated by reference in its entirety.

[0028] In one example, wireless RF communication between the primary network node 102 and the secondary network node 106 utilizes frequency hopping and time slot allocation to transmit and receive data across a superframe (SF). A superframe, also referred to as a superframe interval, is a time interval including time and frequency allocations for data exchange between the primary network node 102 and the secondary network node 106, including the interframe spacing between these allocations. Frequency hopping includes transmitting RF signals by rapidly changing the transmission frequency among many different frequencies occupying a spectrum band. Time slot allocation is a time slot assigned to one or more of the primary network node 102 or the secondary network node 106 for transmitting to one or more of the secondary network node 106 or the primary network node 102. Time slot allocation occurs in half-duplex mode because both the primary network node 102 and the secondary network node 106 switch between transmission mode and reception mode according to the moment specified in the scanning / pairing frame of the exchanged data in the downlink / uplink duration. Additional exemplary details of pairing can be found in commonly assigned U.S. patent application Ser. No. 17 / 576,001, filed on Jan. 14, 2022, entitled “Operating Modes for Testing Monitor Circuits,” which is incorporated by reference in its entirety.

[0029] The WBMS 101 manages the battery unit 108 using the primary network node 102, the battery controller 104, and the secondary network node 106. The primary network node 102 and the secondary network node 106 communicate with each other regarding the status of the battery unit 108.

[0030] As described above, the keep alive process is useful if the vehicle is turned off. For a given keep alive interval N, the keep alive process skips N-1 superframes to wake up in the Nth superframe to handle any activity and then enters the sleep state again. Different methods may be applied to the keep alive process. The first example is a fully active process. In this process, the primary network node turns on its receiver during the uplink portion of the Nth superframe, and the secondary network node transmits its response to the primary network node. The second example is a partially active process. In this process, the primary network node disconnects its receiver during the uplink portion of the Nth superframe, and the secondary network node is not expected to transmit a response. Partially active superframes consume less power than fully active superframes. The keep alive process may have any combination of idle superframes, partially active superframes, and fully active superframes.

[0031] Figure 2 An exemplary WBMS 200 is shown. WBMS 200 is an example of WBMS 101 described above. As shown, WBMS 200 includes a primary network node 102, a battery controller 104, a memory 202, a processor 204, a first primary network node 206, a first plurality or first group of battery cells 208, a second secondary network node 210, and a second plurality or second group of battery cells 212. Additional secondary network nodes 206, 210 may be included, but they are not explicitly shown. The primary network node 102 includes a memory 202 and a processor 204, which is configured to execute a code 218 stored on the memory 202 to perform one or more of the actions attributed to the primary network node 102 herein. In an example, a portion of the memory 202 may be non-transitory, and a portion of the memory 202 may be transient. The secondary network nodes 206, 210 may also include a processor and a memory. For example, as shown, the first sub-network node 206 includes a processor 220 coupled to a memory 222 storing code 224 executable by the processor 220 to perform one or more of the actions attributed herein to the first sub-network node 206 .

[0032] The primary network node 102 is coupled to the battery controller 104 using a first wired connection 110 and wirelessly coupled to each of the secondary network nodes 206, 210. The primary network node 206 is coupled to a first plurality or first group of battery cells 208 using a third wired connection 214 and wirelessly coupled to the primary network node 102. The secondary network node 210 is coupled to a second plurality or second group of battery cells 212 using a fourth wired connection 216 and wirelessly coupled to the primary network node 102. Figure 2 The number of secondary network nodes in WBMS 200 is not limited; rather, the naming convention indicates that each of the secondary network nodes is coupled to a plurality of battery cells.

[0033] In one example, the primary network node 102 is wirelessly coupled to at least eight secondary network nodes 206, 210. In one example, each of the secondary network nodes 206, 210 can be coupled to at least sixteen battery cells using a wired connection. In an example, the WBMS 200 includes one primary network node 102. In other examples, the WBMS 200 includes multiple primary network nodes 102.

[0034] The WBMS 200 manages the first plurality of battery cells 208 and the second plurality of battery cells 212 using the master network node 102, the battery controller 104, the memory 202, the processor 204, the first network node 206, and the second network node 210. The instructions in the memory 202 cause the processor 204 to instruct the master network node 102 to wirelessly communicate with the first network node 206 and the second network node 210 regarding the status of the first plurality of battery cells 208 and the second plurality of battery cells 212. The master network node 102 and the secondary network nodes 206, 210 may communicate using any suitable protocol format.

[0035] Either or both of processors 204 and 220 may include processing circuitry, such as one or more processors. Processors 204 and 220 may include any combination of integrated circuitry, discrete logic circuitry, analog circuitry, such as one or more microprocessors, microcontrollers, digital signal processors, application specific integrated circuits, central processing units, graphics processing units, field programmable gate arrays, and / or any other processing resources. In some examples, processors 204 and 220 may include multiple components, such as any combination of the processing resources listed above, as well as other discrete or integrated logic circuitry, and / or analog circuitry.

[0036] Figure 3A is an exemplary superframe interval 300 that may be used by a wireless battery management system such as WBMS 101. Figure 3A In the embodiment, each of the secondary network nodes 106 receives the downlink from the primary network node 102 and provides an appropriate response. Figure 3B A situation is shown in which a secondary network node (eg, 206, 210, etc.) misses a downlink from the primary network node 102. Referring again to Figure 3A , the term TsMaxRx represents the maximum (Max) time (Ts) allocated for receiving a packet (Rx), and the term TsMaxTx represents the maximum (Max) time (Ts) allocated for transmitting a packet (Tx). The master network node 102 communicates with the first time network node 206, the second time network node 210, and the Nth time network node 301 using, for example, a superframe interval 300. As shown, the superframe interval 300 includes a DL transmission frame 302, a first UL reception frame 304, a second UL reception frame 306, a third UL reception frame 308, a DL protection frame 310, a DL transmission time frame 312, a first transmission to reception frame 314, a first UL reception time frame 316, a second transmission to reception frame 318, a second UL reception time frame 320, a third transmission to reception frame 322, a third UL reception time frame 324, a first DL reception frame 326, a first UL transmission frame 328, a first reception frame 329, a second UL reception frame 330, a third UL reception frame 331, a first UL reception frame 332, a first UL reception frame 333, a second UL reception frame 334, a first UL reception frame 335, a first UL reception frame 336, a second UL reception frame 337, a second UL reception frame 338, a first UL reception frame 339, a second UL reception frame 340, a third UL reception frame 341, a first UL reception frame 342, a first UL reception frame 343, a second UL reception frame 344, a first UL reception frame 345, a first UL transmission frame 346, a first UL reception frame 347, a first UL reception frame 348, a first UL reception frame 349, a second 330, a first received transmission frame 332, a first UL transmission time frame 334, a second DL received frame 336, a second UL transmission frame 338, a second received waiting time 340, a second received transmission frame 342, a second UL transmission time frame 344, a third DL received frame 346, a third UL transmission frame 348, a third received waiting time 350, a third received transmission frame 352, a third UL transmission time frame 354, a first frame 356, a second frame 358, a third frame 360, and a fourth frame 362. The frames 356, 358, 360, and 362 may be referred to herein as time slots 356, 358, 360, and 362, respectively.

[0037] The superframe interval 300 organizes the communication between the primary network node 102 and the secondary network node 106 for wireless battery management purposes. In one example, the superframe interval 300 is a medium access control (MAC) for data exchange between the primary network node 102 and the first secondary network node 206, the second secondary network node 210, and the Nth secondary network node 301. Each of the secondary network nodes 206, 210, 301 in the superframe interval 300 communicates with the primary network node 102 during the time slot as discussed with reference to FIG.

[0038] In one example, the superframe interval 300 starts with a DL protection frame 310. The DL protection frame 310 is a time period to ensure that there is no interference between subsequent SFs. At the time of the DL protection frame 310, the first network node 206 enters a first reception waiting time 330, the second network node 210 enters a second reception waiting time 340, and the Nth network node 301 enters a third reception waiting time 350.

[0039] In the first frame 356 of the superframe interval 300, after the DL protection frame 310, the master network node 102 broadcasts DL to all secondary network nodes 206, 210, 301 using the DL transmission frame 302 during the DL transmission time frame 312. The first network node 206 receives the DL using the first DL reception frame 326, the second network node 210 receives the DL using the second DL reception frame 336, and the Nth secondary network node 301 receives the DL using the third DL reception frame 346. After the DL transmission frame 302, the master network node 102 enters the first transmit-to-receive frame 314 to prepare for receiving UL from each of the secondary network nodes 206, 210, 301. At the same time as the master network node 102 enters the first transmit-to-receive frame 314, the first network node 206 enters the first receive-to-transmission frame 332 to prepare for the first UL transmission to the master network node 102.

[0040] In the second frame 358 of the superframe interval 300, the first sub-network node 206 transmits the first UL using the first UL transmission frame 328 and during the first UL transmission time frame 334. The master network node 102 receives the first UL using the first UL reception frame 304 and during the first UL reception time frame 316. In the second frame 358, the master network node 102 enters the second transmit to receive frame 318 to prepare for receiving the second UL from the second sub-network node 210. The second sub-network node 210 enters the second receive to transmit frame 342 to prepare for transmitting the second UL to the master network node 102.

[0041] In the third frame 360 ​​of the superframe interval 300, the second secondary network node 210 transmits the second UL using the second UL transmission frame 338 and during the second UL transmission time frame 344. The master network node 102 receives the second UL using the second UL reception frame 306 and during the second UL reception time frame 320. In the third frame 360, the master network node 102 enters a third transmit to receive frame 322 to prepare for receiving the third UL from the Nth secondary network node 301. The Nth secondary network node 301 enters a third receive to transmit frame 352 to prepare for transmitting the third UL to the master network node 102.

[0042] In the fourth frame 362 of the superframe interval 300, the Nth network node 301 (eg, a third network node in one example) transmits a third UL using the third UL transmission frame 348 and during the third UL transmission time frame 354. Figure 3A As shown in FIG. 3 , the fourth frame 362 is not necessarily continuous with the third frame 360. The master network node 102 receives the third UL using the third UL reception frame 308 and during the third UL reception time frame 324. The schedule of frames 328, 338, and 348 shown in FIG. 3 may be referred to herein as a default uplink packet transmission schedule.

[0043] Figure 3A An exemplary process is shown, where each time a node (206, 210, 301, etc.) properly receives a DL from the master network node 102 and responds with a UL. Figure 3B An exemplary process is shown that the WBMS may follow if at least one of the secondary nodes (206, 210, 301, etc.) misses a DL from the primary network node 102 during its corresponding frame.

[0044] Figure 3B is another exemplary superframe interval 300 that may be used by a wireless battery management system such as WBMS 101. Figure 3B In the example, the secondary network nodes (eg, 206 , 210 , 301 , etc.) miss the downlink from the primary network node 102 . Figure 3B An example of an exemplary secondary network node's response to missing a downlink from the primary network node 102 is shown. Figure 4A and 4B Another example of an exemplary secondary network node's response to a missed downlink from the primary network node 102 is shown.

[0045] Figure 3B Many of the components in Figure 3A Description, and like numbers represent like components. Figure 3B Also included are a fourth transmit-to-receive frame 368 , a fourth UL receive time frame 370 , a fourth UL receive frame 372 , a fifth transmit-to-receive frame 374 , a fifth UL receive time frame 376 , and a fifth UL receive frame 378 .

[0046] In one example, the first time network node 206 misses the DL transmission frame 302 from the master network node 102 . Figure 3B This missed DL transmission frame is shown with an “X” during the first receive wait time 330. In this example, other secondary nodes, such as the second secondary network node 210 and the Nth secondary node N, successfully receive the DL transmission frame from the primary network node 102. However, in other examples, any number of secondary nodes may miss the DL transmission frame, and then in response to missing the DL transmission frame, may perform the operations described in this example.

[0047] The secondary network node 106 may miss DL transmission frames from the primary network node 102 for various reasons, such as wireless interference (e.g., noise). In one example, the superframe interval 300 is a superframe that occurs one superframe after an idle superframe. That is, the superframe before the superframe interval 300 is a superframe in which the primary network node 102 and the secondary network node 106 are idle to save power. In the superframe interval 300, or in the superframe before the superframe interval 300, the primary network node 102 may receive an interruption that the vehicle has been turned on. In response to turning on the vehicle, the WBMS 101 attempts to start up by activating the primary network node 102 and all secondary network nodes 106. As described above, the WBMS 101 may attempt to complete this startup process within 300ms or less to meet certain performance requirements. In order to complete the startup process, the primary network node 102 checks that all secondary network nodes 106 are functional and responsive by sending DL to each secondary network node 106 and receiving UL back from each secondary network node 106. However, if one of the secondary network nodes 106 misses a DL as described herein, in some systems the secondary network node 106 will have to wait for the next superframe interval to receive the DL from the second DL transmitted by the primary network node 102. The WBMS 101 cannot start properly until all secondary network nodes 106 have received the DL from the primary network node 102 and responded to the primary network node 102. Depending on the length of the superframe interval 300, if the secondary network node 106 misses a DL, the WBMS 101 may not start in time to meet certain performance requirements.

[0048] exist Figure 3B In the example described in , the first time network node 206 is turned on and expects to receive a DL from the master network node 102 during the first frame 356. However, the first time network node 206 misses the DL transmission frame 302 from the master network node 102 during the first reception wait time 330. In response to expecting a DL but not receiving a DL, the first time network node 206 turns on its receiver and listens for other frames transmitted from other secondary network nodes 106. If the first time network node 206 receives a transmission from another secondary network node 106, the first time network node 206 recognizes that the WBMS 101 is active and completes its wake-up operation to prepare for operation.

[0049] In this example, the first time network node 206 misses the DL transmission frame 302 from the master network node 102 during the first reception wait time 330. Therefore, the first time network node 206 fails to transmit UL to the master network node 102 during the first UL transmission time frame 334 (in Figure 3BIn response to missing the DL, the first secondary network node 206 enters a fourth transmit to receive frame 368 to prepare for receiving the UL from another secondary network node 106. Here, at the third frame 360, the first secondary network node 206 receives a fourth UL receive frame 372 (shown as circled) during a fourth UL receive time frame 370. In this example, the second secondary network node 210 transmits the fourth UL receive frame, but the UL receive frame can be from any secondary network node 106.

[0050] The first sub-network node 206 may keep its receiver on during the superframe interval 300 and continue to listen for UL frames. As shown, the first sub-network node 206 enters the fifth transmit-to-receive frame 374 and receives the fifth UL receive frame 378 (shown as circled) during the fifth UL receive time frame 376. The first sub-network node 206 may receive any number of UL frames from other secondary network nodes 106. In other examples, the first sub-network node 206 may stop listening for UL frames after receiving a UL frame from another secondary network node 106.

[0051] If the first time network node 206 wakes up to listen for transmissions from other secondary network nodes 106, it does not need to wake up for the entire superframe. Instead, the first time network node 206 may stay awake long enough to receive a transmission from another secondary network node 106. If it does not receive a transmission from another secondary network node 106, the first time network node 206 may go back to sleep mode or idle mode. And, if the first time network node 206 detects a transmission from another secondary network node 106, it may wait for the next superframe interval to transmit the UL to the primary network node 102 so that it can transmit its UL during the appropriate frame.

[0052] In this example, the first time network node 206 misses the DL from the master network node 102, but is still turned on during the superframe interval 300. This example allows the WBMS 101 to wake up and become functional quickly enough to meet certain performance requirements, particularly when the WBMS 101 exits power saving mode.

[0053] Figure 4A and 4B Exemplary consecutive superframe intervals 400 and 401 are shown that may be used by a wireless battery management system, such as WBMS 101 . Figure 4A A superframe 400 is shown, and Figure 4B Show superframe 401. Figure 4A and 4B In the example, the secondary network nodes (eg, 206 , 210 , 301 , etc.) miss the downlink from the primary network node 102 . Figure 4A and 4BAn example of an exemplary secondary network node 106's response to a missed downlink from the primary network node 102 is shown. Figure 4A and 4B The same components as above for Figure 3A and 3B The same components described above operate similarly. For example, a receive time frame, a DL receive frame, a UL transmit frame, a received transmit frame, etc. are each in Figure 4A and 4B Zhongyu Figure 3A and 3B The similarly named counterparts in operate similarly.

[0054] The master network node 102 uses, for example, a superframe interval 400 (in Figure 4A ) and 401 (in Figure 4B ) communicates with the first sub-network node 206, the second sub-network node 210, and the Nth sub-network node 301. As shown, superframe intervals 400 and 401 include a first DL protection frame 402, a first DL transmission frame 403, a first UL reception frame 404, a second UL reception frame 405, a second DL transmission frame 406, a third UL reception frame 407, a fourth UL reception frame 408, and a fifth UL reception frame 409. The superframe intervals 400 and 401 also include a first DL transmission time frame 410, a first transmission-reception frame 411, a first UL reception time frame 412, a second transmission-reception frame 413, a second UL reception time frame 414, a third transmission-reception frame 415, a third UL reception time frame 416, a second DL protection frame 417, a second DL transmission time frame 418, a fourth transmission-reception frame 419, a fourth UL reception time frame 420, a fifth transmission-reception frame 421, a fifth UL reception time frame 422, a sixth transmission-reception frame 423 and a sixth UL reception time frame 424.

[0055] The superframe intervals 400 and 401 also include a first reception wait time 425, a first received transmission frame 426, a first UL transmission time frame 427, a second reception wait time 428, a second received transmission frame 429, and a second UL transmission time frame 430. The superframe intervals 400 and 401 include a first DL reception frame 431 and a first UL transmission frame 432.

[0056] The superframe intervals 400 and 401 further include a third reception wait time 433, a third reception received transmission frame 434, a third UL transmission time frame 435, a fourth reception wait time 436, a fourth reception received transmission frame 437, and a fourth UL transmission time frame 438. The superframe intervals 400 and 401 further include a second DL reception frame 439, a second UL transmission frame 440, a third DL reception frame 441, and a third UL transmission frame 442.

[0057] The superframe intervals 400 and 401 include a fifth reception wait time 443, a fifth reception transmission frame 444, a fifth UL transmission time frame 445, a sixth reception wait time 446, a sixth reception transmission frame 447, and a sixth UL transmission time frame 448. The superframe intervals 400 and 401 also include a fourth DL reception frame 449, a fourth UL transmission frame 450, a fifth DL reception frame 451, and a sixth UL transmission frame 452. The superframe intervals 400 and 401 also include a first frame 453, a second frame 454, a third frame 455, a fourth frame 456, a fifth frame 457, a sixth frame 458, a seventh frame 459, and an eighth frame 460. The frames 453 to 460 may be referred to herein as time slots 453 to 460, respectively.

[0058] For simplicity, the Figure 4A and 4B However, Figure 4A and 4B Similar to Figure 3A and 3B Operation. Figure 4A and 4B In the example, the master network node 102 transmits the first DL transmission frame 403 during the first frame 453. In this example, the first network node 206 misses the DL transmission. Figure 4A The "X" in refers to a missed DL transmission. In this example, other secondary network nodes 106 (210, 301, etc.) receive the DL transmission. Because the first time network node 206 missed the DL transmission, the first time network node 206 does not transmit an UL transmission frame during the first UL transmission time frame 427. In this example, the first time network node 206 listens for DL ​​transmissions from the primary network node 102 during the next superframe interval 401, rather than listening for UL transmissions from other secondary network nodes 106 during the superframe interval 400 (as described above with respect to Figure 3B If the transmission occurs during superframe interval 401, then WBMS 101 may be operating and first network node 206 may continue to operate normally. Figure 4A , the first sub-network node 206 does not listen for UL transmissions from other secondary network nodes 106 during superframe interval 400. Instead, the first sub-network node 206 listens for transmissions during superframe interval 401, and in this example, receives a DL transmission at a first DL receive frame 431. The first sub-network node 206 then responds to the primary network node 102 with a first UL transmission frame 432. Thus, in this exemplary scenario, the maximum delay is one superframe.

[0059] Figure 5A and 5Bis an example graph of node power consumption according to various examples described herein. Figure 5A Graph 500 of scaled power consumption for secondary network nodes according to various examples herein. The y-axis of graph 500 shows the scaled power consumption, while the x-axis shows the number of network nodes for four different scenarios. Examples are shown for 8 nodes, 16 nodes, 24 nodes, and 32 nodes. The four scenarios shown for each node count are the original scenario, the increased keep-alive frequency scenario, the receive (RX) scenario in the UL frame, and the RX scenario in the next superframe. In one example, the primary node may transmit keep-alive frames at intervals of less than 300ms in this scenario. In the original scenario, the node that missed the DL waits for the next active frame. In the increased keep-alive frequency scenario, the keep-alive frequency is increased so that relatively more superframes have keep-alive signals, while relatively fewer superframes remain idle. The RX scenario in the UL frame includes if the first network node misses the DL in the first superframe, the first network node listens for UL from other secondary network nodes in the first superframe. The above description of Figure 3B This scenario is described in the following. The RX scenario in the next superframe includes if the first time network node misses DL in the first superframe, the first time network node listens to UL from other secondary network nodes in the second superframe. Figure 4A and 4B Describe the situation.

[0060] In the original scenario in graph 500, the scaled power consumption is approximately 4.0 per node for each node count (8, 16, 24, and 32). In the increase keep alive frequency scenario, the scaled power consumption is approximately 7.0 per node for each node count. In the RX scenario in the UL frame, the scaled power consumption per node is between about 4.1 and 4.3 for various node counts. In the RX scenario in the next superframe, the scaled power consumption per node is approximately 5.0 for various node counts. Therefore, graph 500 shows that the RX scenario in the UL frame or the RX scenario in the next superframe consumes less power at the secondary node than the increase keep alive frequency scenario.

[0061] Figure 5B 550 is a graph of scaled power consumption for a primary node (e.g., master network node 102) according to various examples herein. The y-axis of graph 550 shows scaled power consumption, while the x-axis shows the number of network nodes for four different scenarios. Examples are shown for 8 nodes, 16 nodes, 24 nodes, and 32 nodes. The four scenarios shown for each node count are the original scenario described above, the increase keep alive frequency scenario, the receive (RX) scenario in the UL frame, and the RX scenario in the next superframe.

[0062] In the original scenario in graph 550, the scaled power consumption at the primary node is approximately 11 for 8 secondary nodes, approximately 19 for 16 secondary nodes, approximately 27 for 24 secondary nodes, and approximately 35 for 32 secondary nodes. In the increased keep alive frequency scenario, the scaled power consumption at the primary node is approximately 14 for 8 secondary nodes, approximately 22 for 16 secondary nodes, approximately 30 for 24 secondary nodes, and approximately 39 for 32 secondary nodes. In the RX scenario in the UL frame, the scaled power consumption at the primary node is approximately 11 for 8 secondary nodes, approximately 19 for 16 secondary nodes, approximately 27 for 24 secondary nodes, and approximately 35 for 32 secondary nodes. In the RX scenario in the next superframe, the scaled power consumption at the primary node is approximately 11 for 8 secondary nodes, approximately 19 for 16 secondary nodes, approximately 27 for 24 secondary nodes, and approximately 35 for 32 secondary nodes. Thus, graph 500 illustrates that the RX scenario in the UL frame or the RX scenario in the next superframe consumes less power at the secondary node than the increase keep alive frequency scenario. Thus, graph 550 illustrates that the RX scenario in the UL frame or the RX scenario in the next superframe consumes less power at the primary node than the increase keep alive frequency scenario.

[0063] Figure 6 600 is a table according to various examples herein, which shows the approximate power consumption at the primary node and the secondary network node for a network of N nodes. In this example, the secondary node transmits once every 3T and receives once every T, where T is the time interval. The primary node transmits once every T and receives once every 3T. Column 602 shows different scenarios. Column 604 shows the approximate power consumption at the secondary node, where it is assumed that the transmission power is approximately equal to the received power. Column 606 shows the approximate power consumption at the primary node, where it is assumed that the transmission power is approximately equal to the received power. Row 608 is a header row, and rows 610, 612, 614 and 616 respectively show the four different scenarios described above (original, increase keep-alive frequency, RX in UL frame, and RX in next superframe). The values ​​in Table 600 are approximate.

[0064] In one example, the original scenario (row 610) has a secondary node power consumption of 4, and a primary node power consumption of 3+N. The increase keepalive frequency scenario (row 612) has a secondary node power consumption of 7, and a primary node power consumption of 6+N. Therefore, this scenario consumes more power than the original scenario, which is also reflected in Figure 5A and 5B Displayed in.

[0065] Reference again Figure 6, the RX scenario in the UL frame has a secondary node power consumption of 4+(N-1)*p, where p is the probability of error. The RX scenario in the UL frame has a primary node power consumption of 3+N. As an example, in a system with 8 secondary nodes and a 10% probability of error, in this scenario, the secondary node power consumption will be 4+(8-1)(0.10), or approximately 4.7. If the probability of error is 0.1%, the secondary node power consumption will be 4+(8-1)(0.001), or approximately 4.007. Therefore, power consumption decreases as the probability of error decreases. In addition, in this scenario, the secondary node power consumption increases as N increases.

[0066] The RX scenario in the next superframe has a secondary node power consumption of 4+1 / (1-p), where p is the error probability. The RX scenario in the next superframe has a primary node power consumption of 3+N. As an example, in a system with 8 secondary nodes and an error probability of 10%, in this scenario, the secondary node power consumption will be 4+1 / (0.9), or approximately 5.1. If the error probability is 0.1%, the secondary node power consumption will be 4+1 / (0.999), or approximately 5.001. Therefore, in this scenario, power consumption also decreases as the error probability decreases.

[0067] Figure 7 is a flow chart of a method for performing a network restart from a power saving mode according to various examples herein. The steps of method 700 may be performed in any suitable order. In some examples, the above description of Figures 1 to 2 The described hardware components may perform method 700 .

[0068] Method 700 begins at 710, where master network node 102 transmits downlink packets to one or more secondary nodes in a first superframe in a WBMS. In one example, the first superframe may be superframe 300, and the secondary nodes may be secondary nodes 206, 210, and / or 301.

[0069] Method 700 continues at 720, where the first subnode receives a downlink packet. In one example, secondary node 206 fails to receive a downlink packet, and secondary node 210 receives a downlink packet. Thus, in this example, secondary node 210 is the first subnode. In response to failing to receive an expected downlink packet, secondary node 206 may turn on its receiver to listen for uplink packets from other secondary nodes (210, 301, etc.).

[0070] Method 700 continues at 730 where the first sub-node (eg, node 210) transmits a first uplink packet from the first sub-node to the master network node 102 in a first superframe (eg, superframe 300). In one example, the first uplink packet is transmitted using the second UL transmission frame 338.

[0071] The method 700 continues at 740, where the second secondary node (e.g., node 206) receives a first uplink packet in the first superframe. In one example, the first uplink packet is received at the fourth UL receive frame 372. As described above, the second secondary node 206 listens for uplink packets from other secondary nodes, such as node 210. If the second secondary node 206 receives the uplink packet, the second secondary node 206 knows that the WBMS 101 is functioning and can then prepare for operation.

[0072] The method 700 continues at 750, where the second time node transmits a second uplink packet to the master network node 102 during the second superframe. The second time node (e.g., node 206) waits until the next superframe after the first superframe so that the second time node 206 can transmit the second uplink packet during the appropriate time slot.

[0073] Figure 8 is a flow chart of a method for performing a network restart from a power saving mode according to various examples herein. The steps of method 800 may be performed in any suitable order. In some examples, the above description of Figures 1 to 2 The described hardware components may perform the method 800. The method 800 may be performed when the WBMS exits a low power state (eg, a sleep or idle state) and all nodes are reactivated in the WBMS.

[0074] Method 800 begins at 810, where master network node 102 transmits a first downlink packet to one or more secondary nodes in a first superframe in a WBMS. In one example, the first superframe may be superframe 400, and the secondary nodes may be secondary nodes 206, 210, and / or 301. The first downlink packet may be transmitted in a first time slot of superframe 400.

[0075] Method 800 continues at 820, where the first sub-node receives a first downlink packet in a first superframe (e.g., superframe 400). The first downlink packet may be received in a first time slot of superframe 400. In one example, secondary node 206 fails to receive the downlink packet, and secondary node 210 receives the downlink packet. Thus, in this example, secondary node 210 is the first sub-node. In response to failing to receive the expected downlink packet, secondary node 206 may be configured to turn on its receiver to listen for uplink packets from other secondary nodes (210, 301, etc.).

[0076] Method 800 continues at 830, where a second time the node (e.g., node 206) fails to receive the first downlink packet in the first superframe. In one example, the first reception wait time 425 is Figure 4AThe "X" in refers to a missed DL transmission at the node 206. The secondary node 206 may miss the first downlink packet due to interference or because the secondary node 206 was not listening to the first downlink packet when the primary node sent it.

[0077] The method 800 continues at 840, where the first node (e.g., node 210) transmits a first uplink packet to the master network node 102 in the first superframe 400. As an example, the first uplink packet is transmitted using the second UL transmission frame 440. The node 210 sends the first uplink packet in response to receiving the first downlink packet. Each of the secondary nodes may be able to determine its corresponding time slot within the superframe 400, as explained in commonly assigned U.S. patent application Ser. No. 17 / 828,895, entitled “Efficient Unicast Super Frame Communications,” filed on May 31, 2022, which is incorporated by reference in its entirety.

[0078] Method 800 continues at 850, where the master network node 102 transmits a second downlink packet to the one or more secondary nodes in a second superframe. In one example, the second superframe can be superframe 401, and the first and second superframes can be consecutive superframes. In one example, the second downlink packet can be transmitted using a second DL transmission frame 406. The second downlink packet can be transmitted in a second time slot in superframe 401.

[0079] Method 800 continues at 860 where the second node (e.g., node 206) receives a second downlink packet in the second superframe 401. As an example, the second downlink packet is received at the first DL receive frame 431. The second downlink packet may be received in a second time slot of the second superframe 401.

[0080] The method 800 continues at 870, where the secondary node (e.g., node 206) transmits a second uplink packet to the master network node 102 in the second superframe 401. As an example, the second uplink packet is transmitted at the first UL transmission frame 432. The second uplink packet may be transmitted in a third time slot of the second superframe 401.

[0081] In the examples herein, a first time node that fails to receive an expected downlink packet from a master node during an active superframe may turn on its receiver to opportunistically listen for other frames transmitted from other secondary nodes to the master node during an active superframe. If the first time node receives a transmission from another secondary node, the first time node wakes up and enters an active state. In other examples herein, a first time node that misses a downlink packet from a master node may use its receiver to listen during the next superframe instead of the current superframe. If there is any activity in the next superframe, the WBMS is active and the first time node may continue to operate normally. In the examples herein, the node may consume minimal power during a disconnected state (e.g., a keep-alive power saving state) while still being able to quickly start up and operate the WBMS in less than 300ms.

[0082] The term "coupled" is used throughout this specification. The term may encompass connections, communications, or signal paths that achieve a functional relationship consistent with this specification. For example, if device A generates a signal to control device B to perform an action, then: in a first instance, device A is coupled to device B; or in a second instance, device A is coupled to device B through an intermediate component C, provided that the intermediate component C does not substantially change the functional relationship between device A and device B, so that device B is controlled by device A via the control signal generated by device A.

[0083] A device "configured to" perform a task or function may be configured (e.g., programmed and / or hardwired) to perform the function when manufactured by a manufacturer, and / or may be configurable (or reconfigurable) by a user after manufacture to perform the function and / or other additional or alternative functions. Configuration may be performed through firmware and / or software programming of the device, through the construction and / or layout of the device's hardware components and interconnections, or a combination thereof.

[0084] Unless otherwise stated, "about," "approximately," or "substantially" preceding a value means + / - 10% of the stated value. Modifications are possible in the described examples, and other examples are possible within the scope of the claims.

Claims

1. A wireless battery management system (WBMS), comprising: one or more battery cells; a master node configured to broadcast a downlink packet in a first superframe; a first subnode coupled to the first group of battery cells, the first subnode being configured to: receiving the downlink packet; as well as transmitting a first uplink packet to the master node during the first superframe; as well as a second secondary node coupled to the second group of battery cells, the second secondary node being configured to: receiving the first uplink packet from the first sub-node in the first superframe; as well as A second uplink packet is transmitted to the master node during a second superframe. 2 . The WBMS according to claim 1 , wherein the first superframe and the second superframe are consecutive superframes. The WBMS according to claim 1 , wherein the second time node fails to receive the downlink packet.

4. The WBMS of claim 3, wherein the second node comprises a receiver, and wherein, In response to failing to receive the downlink packet, the second node turns on the receiver. 5 . The WBMS of claim 1 , wherein the first time node receives the downlink packet in a first time slot of the first superframe and transmits the first uplink packet in a second time slot of the first superframe.

6. The WBMS of claim 5, wherein the second secondary node receives the first uplink packet in the second time slot.

7. A method comprising: transmitting a downlink packet from a primary node to one or more secondary nodes in a first superframe in a wireless battery management system (WBMS); receiving the downlink packet at a first receiving node; transmitting a first uplink packet from the first sub-node to the master node in the first superframe; receiving the first uplink packet at a secondary node in the first superframe; as well as A second uplink packet is transmitted from the secondary node to the primary node during a second superframe. 8 . The method of claim 7 , wherein the first subnode is coupled to a first group of battery cells and the second subnode is coupled to a second group of battery cells.

9. The method of claim 7, wherein the master node transmits the downlink packet in a first time slot of the first superframe, and the first sub-node receives the downlink packet in the first time slot.

10. The method of claim 9, wherein the first time node transmits the first uplink packet in a second time slot of the first superframe.

11. The method of claim 10, wherein the second time node fails to receive the downlink packet.

12. The method of claim 11, wherein the second node comprises a receiver, and wherein, In response to failing to receive the downlink packet, the second node turns on the receiver.

13. The method of claim 12, wherein the second secondary node receives the first uplink packet in the second time slot.

14. The method of claim 7, wherein the first superframe and the second superframe are consecutive superframes.

15. A method comprising: transmitting a first downlink packet from the primary node to the one or more secondary nodes in a first superframe; receiving the first downlink packet at a first sub-node in the first superframe; failure to receive the first downlink packet at a secondary node in the first superframe; transmitting a first uplink packet from the first sub-node to the master node in the first superframe; transmitting a second downlink packet from the primary node to the one or more secondary nodes in a second superframe; receiving, at the secondary node, the second downlink packet in the second superframe; as well as A second uplink packet is transmitted from the secondary node to the primary node in the second superframe.

16. The method of claim 15, wherein the first superframe and the second superframe are consecutive superframes.

17. The method of claim 15, wherein the first subnode is coupled to a first group of battery cells and the second subnode is coupled to a second group of battery cells.

18. The method of claim 15, wherein the master node transmits the first downlink packet in a first time slot of the first superframe, and the first sub-node receives the first downlink packet in the first time slot.

19. The method of claim 18, wherein the primary node transmits the second downlink packet in a second time slot of the second superframe, and the secondary node receives the second downlink packet in the second time slot of the second superframe.

20. The method of claim 19, wherein the second sub-node transmits the second uplink packet in a third time slot of the second superframe.

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