Wireless battery management reverse wake up
In some examples, a battery management system (BMS) includes a set of battery cells and a secondary network node coupled to the set of battery cells. The secondary network node is configured to, responsive to determination by the secondary network node of an exception event, wirelessly transmit a series of periodically repeating reverse wake up data frames to a primary network node. The secondary network node is also configured to, responsive to receipt of a synchronization frame from the primary network node after transmitting the series of reverse wake up data frames, transmit an uplink data frame to the primary network node.
1 . A battery management system (BMS), comprising:
a set of battery cells; and
a secondary network node coupled to the set of battery cells, the secondary network node configured to:
responsive to determination by the secondary network node of an exception event, wirelessly transmit a series of periodically repeating reverse wake up data frames to a primary network node; and
responsive to receipt of a synchronization frame from the primary network node after transmitting the series of reverse wake up data frames, transmit an uplink data frame to the primary network node.
2 . The BMS of claim 1 , wherein:
the series of reverse wake up data frames is a first series of reverse wake up data frames; and
the secondary network node is configured to, responsive to not receiving a synchronization frame from the primary network node within a first amount of time after transmitting the first series of reverse wake up data frames, transmit a second series of reverse wake up data frames.
3 . The BMS of claim 2 , wherein the second series of reverse wake up data frames includes a greater number of reverse wake up data frames than the first series of reverse wake up data frames.
4 . The BMS of claim 1 , wherein each reverse wake up data frame includes an identifier of the secondary network node, an identifier of the exception event, a number of reverse wake up data frames included in the series of reverse wake up data frames, and an indicator of a current reverse wake up data frame being transmitted in the series of reverse wake up data frames.
5 . The BMS of claim 4 , wherein the indicator of the current reverse wake up data frame being transmitted in the series of reverse wake up data frames is one of a number of the current reverse wake up data frames in the series of reverse wake up data frames or a number of reverse wake up data frames remaining in the series of reverse wake up data frames.
6 . The BMS of claim 1 , wherein the BMS further comprises the primary network node wirelessly coupled to the secondary network node, the primary network node configured to:
while in a low power state, wake from the low power state for a second period of time;
perform sampling for the second period of time;
responsive to not detecting a reverse wake up data frame via the sampling, return to the low power state; and
responsive to detecting a reverse wake up data frame from among the series of reverse wake up data frames, transmit the synchronization frame after an end of the series of reverse wake up data frames.
7 . The BMS of claim 1 , wherein the secondary network node is configured to generate each reverse wake up data frame to include an identifier of the exception event.
8 . The BMS of claim 7 , further comprising:
a second set of battery cells; and
a third network node coupled to the second set of battery cells, wherein the third network node is configured to exit a low power state in response to the identifier of the exception event.
9 . A method, comprising:
a secondary network node transmitting, responsive to determination of an exception event, a periodically repeating series of reverse wake up data frames to a primary network node; and
responsive to receipt of a synchronization frame from the primary network node after transmitting the series of reverse wake up data frames, transmitting, by the secondary network node, an uplink data frame to the primary network node.
10 . The method of claim 9 , wherein the series of reverse wake up data frames is a first series of reverse wake up data frames, the method further comprising responsive to not receiving a synchronization frame from the primary network node within a first amount of time after transmitting the first series of reverse wake up data frames, transmitting a second series of reverse wake up data frames.
11 . The method of claim 9 , wherein each reverse wake up data frame includes an identifier of the secondary network node, an identifier of the exception event, a number of reverse wake up data frames included in the series of reverse wake up data frames, and an indicator of a current reverse wake up data frame being transmitted in the series of reverse wake up data frames.
12 . The method of claim 9 , further comprising:
while in a low power state, waking, by the primary network node, from the low power state for a sample duration;
performing, by the primary network node, sampling during the sample duration;
responsive to not detecting a reverse wake up data frame via the sampling, returning, by the primary network node, to the low power state; and
responsive to detecting a reverse wake up data frame from among the series of reverse wake up data frames, transmitting, by the primary network node, the synchronization frame after an end of the series of reverse wake up data frames.
13 . The method of claim 9 , further comprising providing, by the secondary network node, each reverse wake up data frame including an identifier of the exception event.
14 . The method of claim 9 , wherein controlling the secondary network node includes instructing the secondary network node to enter a low power state.
15 . The method of claim 9 , wherein the secondary network node is coupled to a set of battery cells, and wherein controlling the secondary network node includes disabling at least one battery cell of the set of battery cells.
16 . A method, comprising:
while in a low power state, waking, by a primary network node, from the low power state for a sample duration;
performing, by the primary network node, sampling during the sample duration;
responsive to not detecting a reverse wake up data frame via the sampling, returning, by the primary network node, to the low power state; and
responsive to detecting a reverse wake up data frame from among a series of reverse wake up data frames transmitted by a secondary network node, transmitting, by the primary network node, a synchronization frame after an end of the series of reverse wake up data frames.
17 . The method of claim 16 , wherein the secondary network node is coupled to a set of battery cells, the method further comprising:
responsive to determination of an exception event associated with at least one battery cell of the set of battery cells, transmitting, by the secondary network node, the series of reverse wake up data frames; and
responsive to receipt of the synchronization frame from the primary network node after transmitting the series of reverse wake up data frames, transmitting, by the secondary network node, an uplink data frame to the primary network node.
18 . The method of claim 16 , wherein each reverse wake up data frame includes an identifier of an exception event.
19 . The method of claim 18 , further comprising receiving, responsive to transmitting the synchronization frame, an uplink data frame from the secondary network node, the uplink data frame including battery cell information related to the exception event.
20 . The method of claim 19 , wherein each reverse wake up data frame further includes an identifier of the secondary network node, a number of reverse wake up data frames included in the series of reverse wake up data frames, and an indicator of a current reverse wake up data frame being transmitted in the series of reverse wake up data frames.