JP2021142821A - Electrical device - Google Patents

Abstract

To maintain communication connection even in a stop state and suppress power consumption by a master unit.SOLUTION: An electrical device 91 includes a master unit 10 and a plurality of slave units 20a to 20c. In an operation state, the master unit 10 performs a predetermined master function F1 and each of the slave units 20a to 20c performs a slave function f2 consuming lower power than that in the master function F1, so that wireless communication connection is maintained. On the other hand, in a stop state Q, substitute states Q1 to Q3 are established in which the slave unit 20 performs the master function F1 and the master unit 10 performs the slave function f2 in at least a predetermined period, the communication connection is maintained while suppressing the power consumption by the master unit 10 as compared with a case where the master unit 10 always performs the master function F1.SELECTED DRAWING: Figure 2

Description

The present invention relates to an electric device having a wireless device.

Some electrical devices have a master unit and a plurality of slave units, and predetermined information is transferred between the master unit and the plurality of slave units by wireless communication. Then, as a document showing such a technique, there is the following Patent Document 1.

Japanese Patent No. 6093448

Normally, in such an electric device, the master unit and each slave unit stop wireless communication in the stopped state in which the above-mentioned delivery is not performed. Then, when the operating state is reached, which is the state in which the above-mentioned delivery should be performed, the master unit and each slave unit start a communication connection for wireless communication.

However, since it takes time to connect to the communication, it is not possible to start wireless communication promptly when the operation is started. Therefore, the present inventor has examined maintaining a communication connection between the master unit and the slave unit even in the stopped state. In this case, since the communication connection is maintained, wireless communication can be started promptly when the operation state is established. However, the present inventor has focused on the following problems.

That is, in such an electric device, wireless communication is usually performed by the master unit having a predetermined parent function and the slave unit having a child function that consumes less power than the parent function. Therefore, if the communication connection is maintained even in the stopped state, the power consumption by the master unit becomes even larger. Therefore, for example, if the power supply that supplies power to the master unit and the power supply that supplies power to the slave unit are different, the power consumption of the power supply that supplies power to the master unit becomes large.

The present invention has been made in view of the above circumstances, and a main object of the present invention is to maintain a communication connection even in a stopped state and to suppress power consumption by a master unit.

The electric device of the present invention has a master unit and a plurality of slave units. In an operating state in which predetermined information is exchanged between the master unit and the slave unit by wireless communication, the master unit performs a predetermined parent function and each slave unit is the parent. By carrying out a child function that consumes less power than the function, the communication connection of the wireless communication is maintained.

In the stopped state in which the predetermined information is not exchanged between the master unit and the slave unit, the slave unit takes on the master function and the master unit performs the master function at least for a predetermined period of time. By becoming a surrogate state that bears the child function, the communication connection is maintained while suppressing the power consumption by the master unit as compared with the case where the master unit always bears the parent function.

According to the present invention, in the stopped state, the communication connection is maintained while suppressing the power consumption by the master unit by acting as a proxy state for at least a predetermined period. Therefore, it is possible to maintain the communication connection even in the stopped state and suppress the power consumption by the master unit.

Schematic diagram showing communication in the operating state of the electrical equipment of the first embodiment Schematic diagram showing communication in a stopped state of electrical equipment Time chart showing communication when electrical equipment is stopped Image diagram showing power consumption in communication when electrical equipment is stopped Schematic diagram showing communication in a stopped state of the electric device of the second embodiment Time chart showing communication when electrical equipment is stopped

Next, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments, and can be appropriately modified and implemented without departing from the spirit of the invention.

[First Embodiment]
First, the outline of the first embodiment will be described. As shown in FIG. 1, the electric device 91 is a battery monitoring system that monitors an assembled battery 40 having a plurality of cell batteries 45, and is mounted on a vehicle. The electric device 91 has a master unit 10 and a plurality of slave units 20. The slave unit 20 is installed in each battery group 44 in which a plurality of cell batteries 45 are grouped, and acquires battery information which is information about the cell battery 45 from the battery group 44 corresponding to the slave unit 20. The master unit 10 acquires battery information from each slave unit 20a to 20c by wireless communication. The master unit 10 is supplied with power from an auxiliary battery 30 different from the assembled battery 40, and each slave unit 20 is supplied with power from a battery group 44 corresponding to itself.

When the power switch 50 of the vehicle is turned on, the electric device 91 is in the operating state P as shown in FIG. 1, and when the power switch 50 is turned off, the electric device 91 is in the stopped state Q as shown in FIG. In the operating state P shown in FIG. 1, the slave unit 20 transmits battery information to the master unit 10 by wireless communication, while in the stopped state Q shown in FIG. 2, the slave unit 20 sends battery information to the master unit 10. Do not send.

In the operating state P shown in FIG. 1, the electric device 91 is a master unit because the master unit 10 is responsible for a predetermined parent function F1 and each slave unit 20 is responsible for a child function f2 that consumes less power than the master function F1. A communication connection for wireless communication is maintained between the 10 and each slave unit 20.

On the other hand, in the stopped state Q shown in FIG. 2, the master unit 10 is always the parent because the slave unit 20 takes charge of the parent function F1 and the master unit 10 takes charge of the child function f2 in the surrogate states Q1 to Q3 for at least a predetermined period. The communication connection of wireless communication is maintained while suppressing the power consumption by the master unit 10 as compared with the case of carrying out the function F1. In the proxy states Q1 to Q3, the slave unit 20 responsible for the parent function F1 performs wireless communication with the master unit 10 and also wirelessly communicates with each slave unit 20 other than itself. Specifically, the electric device 91 executes the following predetermined order control and equalization control in the stopped state Q.

In the predetermined order control, for example, as shown by the broken line arrow in FIG. 2, a plurality of slave units 20a to 20c take turns taking charge of the parent function F1 in a predetermined order. Then, when the stopped state Q is changed to the operating state P, the predetermined order shown in FIG. 2 is interrupted, the master unit 10 takes charge of the parent function F1 as shown in FIG. 1, and the interrupted timing in the predetermined order is changed. Be remembered. After that, when the operating state P changes to the stopped state Q shown in FIG. 2, the slave unit 20 takes charge of the parent function F1 in order based on the memory in the continuation of the predetermined order.

In the following, the ratio of the time that one slave unit 20 takes charge of the parent function F1 within a predetermined unit time is referred to as the "parent function charge rate" of the slave unit 20.

In the equalization control, each slave unit 20 changes the parent function charge rate based on the state of its own power source as the battery group 44 that supplies power to itself. Specifically, in each of the slave units 20a to 20c, the slave unit 20 having a charge amount of the own power supply larger than the predetermined amount has a parent function than the slave unit 20 having a predetermined amount of charge of the own power source. The charge rate is high. As a result, the charge amount of each battery group 44a to 44c is equalized. Further, each slave unit 20 does not carry the parent function F1 when the charge amount of the own power source is less than a predetermined threshold value. As a result, it is possible to avoid a situation in which each slave unit 20 takes on the parent function F1 even though the charge amount of its own power source is small.

Next, the details of the present embodiment will be described in a form supplementing the outline of the first embodiment shown above.

FIG. 1 is a schematic view showing an operating state P in the electric device 91 of the present embodiment. The assembled battery 40 has a first battery group 44a, a second battery group 44b, and a third battery group 44c as the battery group 44. These battery groups 44a to 44c are electrically connected in series. A plurality of cell batteries 45 constituting each battery group 44 are also electrically connected in series. Each cell battery 45 is a lithium battery or the like.

The electric device 91 has a first slave unit 20a, a second slave unit 20b, and a third slave unit 20c as the slave unit 20. The first slave unit 20a corresponds to the first battery group 44a, the second slave unit 20b corresponds to the second battery group 44b, and the third slave unit 20c corresponds to the third battery group 44c. Each slave unit 20 is electrically connected to the battery group 44 corresponding to itself by a power supply wiring 24, whereby power can be supplied from the battery group 44 corresponding to itself.

Further, each slave unit 20 has a plurality of detection lines 25, and the plurality of detection lines 25 can detect the voltage of each cell battery 45 in the battery group 44 corresponding to the slave unit 20. Specifically, the detection line 25 is electrically connected to both ends of the battery group 44 and between the cell batteries 45 constituting the battery group 44. Each slave unit 20 has a slave unit antenna 21 for wireless communication with the master unit 10. The battery information transmitted by each slave unit 20 to the master unit 10 includes, for example, information regarding the voltage of each cell battery 45, information regarding the temperature, and the like.

Further, each slave unit 20 equalizes the charge amount of each cell battery 45 by discharging the cell battery 45 having a charge amount larger than that of the other cell battery 45 via the detection line 25. It is configured to be able to perform processing. Then, each slave unit 20 performs the cell battery equalization processing described above based on a command from the master unit 10 by wireless communication.

The master unit 10 has a master unit antenna 12 for wireless communication with each slave unit 20a to 20c. Further, the master unit 10 is electrically connected to the auxiliary battery 30 such as a lead battery by the power supply wiring 13, and is also connected to the power switch 50 of the vehicle by the signal line 15. Then, when the power switch 50 is turned on at the timing when the master unit 10 is responsible for the child function f2 in the stopped state Q, the master unit 10 maintains the slave unit 20 which is responsible for the master function F1. Send a parent function conversion command by the existing communication connection. As a result, the master unit 10 takes charge of the parent function F1 and the slave unit 20 takes charge of the child function f2, and the transition from the stopped state Q to the operating state P occurs.

On the other hand, when the power switch 50 is turned on at the timing when the master unit 10 is in charge of the master function F1 in the stopped state Q, the master unit 10 is in the stopped state as it is without sending the master function conversion command to the slave unit 20. Transition from Q to operating state P. In the operating state P, the master unit 10 charges the charge amount of each battery group 44a to 44c and the charge of each cell battery 45 in each battery group 44 based on the battery information transmitted from each slave unit 20a to 20c. Recognize variations in quantity. Then, various commands and the like are transmitted from the master unit 10 to each slave unit 20 by wireless communication.

When the power switch 50 is turned off, the master unit 10 transmits a stop command for setting the stop state Q to the slave units 20a to 20c by a wireless signal. As a result, the electric device 91 transitions from the operating state P to the stopped state Q. In the stopped state Q, battery information, commands, and the like are not transmitted wirelessly, and the communication connection is simply maintained.

Next, the parent function F1 and the child function f2 will be described. The parent function F1 is an active function for maintaining a communication connection with a device responsible for the child function f2. Specifically, for example, a function for scheduling communication with each device responsible for the child function f2 and a child function. It includes a function of actively transmitting radio waves to each device responsible for f2. On the other hand, the child function f2 is a passive function for maintaining a communication connection with the device carrying the parent function F1, for example, a function of returning a radio wave to a radio wave transmitted from the device carrying the parent function F1. include. Therefore, when the parent function F1 is carried out, more power is consumed than when the child function f2 is carried out. The size of "◯" surrounding "F1" and "f2" in FIGS. 1, 2, 4, and 5 indicates the magnitude of power consumption.

The master unit 10 is supplied with power only from the auxiliary battery 30 and is not supplied with power from the assembled battery 40, at least in the stopped state Q. Further, each slave unit 20 is also supplied with power only from the battery group 44 corresponding to itself, and is not supplied with power from the other battery group 44 or the auxiliary battery 30 at least in the stopped state Q. Therefore, at least in the stopped state Q, the master unit 10 and the slave units 20a to 20c are supplied with power from separate and independent power sources.

FIG. 2 is a schematic view showing communication in the stopped state Q of the electric device 91. In the following, a state in which the master unit 10 is responsible for the parent function F1 and each slave unit 20a to 20c is responsible for the child function f2 is referred to as a “normal state Q0”. Further, a state in which the first slave unit 20a is responsible for the parent function F1 and the master unit 10, the second slave unit 20b, and the third slave unit 20c are responsible for the child function f2 is defined as the "first proxy state Q1". Further, a state in which the second slave unit 20b is responsible for the parent function F1 and the master unit 10, the first slave unit 20a, and the third slave unit 20c are responsible for the child function f2 is referred to as a "second proxy state Q2". Further, a state in which the third slave unit 20c is responsible for the parent function F1 and the master unit 10, the first slave unit 20a, and the second slave unit 20b are responsible for the child function f2 is referred to as a "third surrogate state Q3".

In the predetermined order control, for example, as shown by the broken line arrow in FIG. 2, the states are changed in the order of the normal state Q0 → the first surrogate state Q1 → the second surrogate state Q2 → the third surrogate state Q3 → the normal state Q0 again. Specifically, in the normal state Q0 shown in the upper right of FIG. 2, the master unit 10 wirelessly communicates with each of the slave units 20a to 20c. After that, in the first surrogate state Q1 shown in the upper left of FIG. 2, the first slave unit 20a wirelessly communicates with the master unit 10, the second slave unit 20b, and the third slave unit 20c. After that, in the second surrogate state Q2 shown in the lower left of FIG. 2, the second slave unit 20b wirelessly communicates with the master unit 10, the first slave unit 20a, and the third slave unit 20c. After that, in the third surrogate state Q3 shown in the lower right of FIG. 2, the third slave unit 20c wirelessly communicates with the master unit 10, the first slave unit 20a, and the second slave unit 20b.

FIG. 3 is a time chart when the predetermined order control is performed as described above. When shifting from the normal state Q0 to the first surrogate state Q1, the parent function F1 and the child function f2 are exchanged between the master unit 10 and the first slave unit 20a, and the second slave unit 20b is replaced. And the third slave unit 20c changes the communication connection from the master unit 10 to the first slave unit 20a. When the reconnection is established, the first surrogate state Q1 is reached. Then, in the present embodiment, for each of the slave units 20a to 20c and the master unit 10, such a change of communication connection establishes a new communication connection from a state in which no communication connection is made with any of the devices. The protocol is faster than in the case.

After that, when shifting from the first surrogate state Q1 to the second surrogate state Q2, the parent function F1 and the child function f2 are exchanged between the first slave unit 20a and the second slave unit 20b. , The master unit 10 and the third slave unit 20c change the communication connection from the first slave unit 20a to the second slave unit 20b. When the reconnection is established, the second surrogate state Q2 is reached.

After that, when shifting from the second surrogate state Q2 to the third surrogate state Q3, the parent function F1 and the child function f2 are exchanged between the second slave unit 20b and the third slave unit 20c. , The master unit 10 and the first slave unit 20a change the communication connection from the second slave unit 20b to the third slave unit 20c. When the reconnection is established, the third surrogate state Q3 is reached.

After that, when shifting from the third surrogate state Q3 to the normal state Q0, the parent function F1 and the child function f2 are exchanged between the third slave unit 20c and the master unit 10, and the first child is replaced. The machine 20a and the second handset 20b change the communication connection from the third handset 20c to the base unit 10. When the reconnection is established, the normal state Q0 is reached.

FIG. 4 is a time chart showing an image of power consumption when the predetermined order control is performed as described above. In the normal state Q0, the power consumption of the master unit 10 increases because the master unit 10 takes charge of the master function F1. In the first surrogate state Q1, the power consumption of the first slave unit 20a increases because the first slave unit 20a takes charge of the parent function F1. In the second surrogate state Q2, the power consumption of the second slave unit 20b increases because the second slave unit 20b takes charge of the parent function F1. In the third surrogate state Q3, the power consumption of the third slave unit 20c increases because the third slave unit 20c takes charge of the parent function F1.

Then, in the middle of this predetermined order control, when the power switch 50 of the vehicle is turned from OFF to ON and the electric device 91 changes from the stopped state Q to the operating state P, the memory and the like possessed by the master unit 10 and the like are generated. The interrupted timing in this predetermined order control is stored in. Then, when the stop state Q is reached again, the predetermined order control is restarted from the interrupted timing based on the memory.

Next, equalization control will be described with reference to FIG. In this equalization control, the states are changed in the order different from the broken line arrow shown in FIG. In this equalization control, for example, the frequency of carrying out the parent function F1 in each of the slave units 20a to 20c may be changed according to the charge amount of each battery group 44a to 44c, or each time the parent function F1 is carried out. The time may be changed, or both may be changed. The charge amount of each of the battery groups 44a to 44c is calculated based on, for example, the battery information acquired by the master unit 10 from the slave units 20a to 20c in the operating state P.

Specifically, for example, when the charge amount of the first battery group 44a is larger than the charge amount of the second battery group 44b and the third battery group 44c, as equalization control, it is usually shown in the upper right of FIG. The repeating state is changed in the order of the state Q0 → the first surrogate state Q1 shown in the upper left of FIG. 2 → the normal state Q0 shown in the upper right of FIG. 2 again. As a result, it is estimated that the charge amount of the first battery group 44a is reduced and the charge amount is substantially equal to the charge amount of the second battery group 44b and the third battery group 44c. conduct.

Further, for example, when the charge amount of the first battery group 44a is larger than the charge amount of the second battery group 44b and the charge amount of the second battery group 44b is larger than the charge amount of the third battery group 44c. The equalization control is controlled as follows. That is, the normal state Q0 shown in the upper right of FIG. 2 → the first surrogate state Q1 shown in the upper left of FIG. 2, the second surrogate state Q2 shown in the lower left of FIG. Transition the state. Then, at this time, the period of the first surrogate state Q1 is made longer than the period of the second surrogate state Q2. That is, the time per time for the first slave unit 20a to take charge of the parent function F1 is made longer than the time per time for the second handset 20b to take charge of the parent function F1. As a result, the charge amount of the first battery group 44a is reduced, the charge amount of the second battery group 44b is smaller than that, and the charge amount of the first battery group 44a and the second battery group 44b is reduced to that of the third battery group. When it is estimated that the charge amount of 44c is substantially equal to that of the charge amount, the above-mentioned predetermined order control is performed thereafter.

According to this embodiment, the following effects can be obtained. In the stopped state Q, the communication connection is maintained while suppressing the power consumption by the master unit 10 as compared with the case where the master unit 10 always bears the parent function F1 by being in the proxy states Q1 to Q3 for at least a predetermined period. Therefore, the communication connection can be maintained even in the stopped state Q, and the power consumption by the master unit 10 can be suppressed.

Specifically, the master unit 10 is supplied with power from the auxiliary battery 30, and each slave unit 20 is supplied with power from the assembled battery 40. Therefore, as compared with the case where the master unit 10 always bears the master function F1, a part of the power consumption of the auxiliary battery 30 is taken over by the power consumption of the assembled battery 40. Therefore, it is possible to avoid intensive consumption of the electric power of the auxiliary battery 30.

Further, the slave units 20a to 20c are supplied with power from the separate battery groups 44a to 44c in the assembled battery 40. Then, in the stopped state Q, the plurality of slave units 20 take turns taking charge of the parent function F1. Therefore, it is possible to avoid intensive consumption of the electric power of any one of the plurality of battery groups 44a to 44c.

Further, in the equalization control, each slave unit 20a to 20c has a charge amount of its own power source more than the predetermined amount than the slave unit 20 in which the charge amount of its own power source as the battery group 44 that supplies power to itself is a predetermined amount. The handset 20 with many handsets has a higher rate of parent function charge. Therefore, the charge amount of each battery group 44a to 44c can be equalized.

Therefore, this equalization control equalizes the charge amount of each battery group 44, and the cell battery equalization process by each slave unit 20 equalizes the charge amount of each cell battery 45 in each battery group 44. Therefore, the charge amount of all the cell batteries 45 constituting the assembled battery 40 can be equalized to the same amount.

Further, each slave unit 20 does not carry the parent function F1 when the charge amount of the own power source is less than a predetermined threshold value. Therefore, it is possible to avoid a situation in which each slave unit 20 takes on the parent function F1 even though the charge amount of its own power source is small.

Further, in the predetermined order control, in the stopped state Q, the plurality of slave units 20a to 20c and the like take charge of the parent function F1 in the predetermined order. Then, when the stopped state Q is changed to the operating state P, the above-mentioned predetermined order is interrupted, the master unit 10 takes charge of the parent function F1, and the interrupted timing in the above-mentioned predetermined order is stored. After that, when the operating state P is changed to the stopped state Q again, the slave units 20a to 20c and the like take charge of the parent function F1 in order based on the memory, in the continuation of the predetermined order. Therefore, it does not start from the beginning of the predetermined order again. Therefore, it is possible to avoid intensive consumption of the electric power of the battery group 44 that supplies power to the first slave unit 20 in the predetermined order.

Further, in each of the proxy states Q1 to Q3, the slave unit 20 responsible for the parent function F1 makes a communication connection with the other slave unit 20. Therefore, when the stopped state Q is changed to the operating state P, the other slave units 20 can respond by changing the communication connection from the slave unit 20 that has been responsible for the parent function F1 to the master unit 10. .. In the present embodiment, such a reconnection of communication connections is a faster protocol than a case where a new communication connection is established from a state in which no communication connection is established with any of the devices. Therefore, when the stopped state Q is changed to the operating state P, wireless communication can be efficiently and promptly started between the master unit 10 and the other slave units 20.

[Second Embodiment]
Next, the second embodiment will be described. In the following embodiments, the same or corresponding members as those in the previous embodiments are designated by the same reference numerals. However, the electric device itself is designated by a different reference numeral for each embodiment. The present embodiment will be described with reference to the first embodiment and focusing on differences from the first embodiment.

First, the outline of the second embodiment will be described. As shown in FIG. 5, in the electric device 92 of the present embodiment, in the proxy states Q1 to Q3, the slave unit 20 carrying the parent function F1 and the other slave unit 20 do not perform wireless communication. That is, in the electrical device 92, in the proxy states Q1 to Q3, the slave unit 20 and the master unit 10 that carry out the parent function F1 perform wireless communication, while the other slave units 20 are the slave unit 20 and the slave unit that bears the parent function F1. Wireless communication is disabled for any of the master units 10. After that, before the wireless communication between the other slave unit 20 and the master unit 10 is interrupted, the master unit 10 reaches the normal state Q0 which is responsible for the master function F1, so that the wireless communication between the other slave unit 20 and the master unit 10 is performed. Communication is resumed.

In the operating state P, each slave unit 20 determines that the communication with the master unit 10 is interrupted on the condition that the communication with the master unit 10 is not performed for the predetermined first interruption determination time or longer. On the other hand, in the stopped state Q, each slave unit 20 communicates with the master unit 10 on the condition that communication with the master unit 10 is not performed for the second determination time, which is longer than the first interruption determination time. Judged as interrupted.

Next, the details of the second embodiment will be described in a form supplementing the outline of the second embodiment shown above.

FIG. 5 is a schematic view showing communication in the stopped state Q of the electric device 92. In the predetermined order control, for example, as shown by the broken line arrow in FIG. 5, the normal state Q0 → the first surrogate state Q1 → the normal state Q0 → the second surrogate state Q2 → the normal state Q0 → the third surrogate state Q3 → the normal state again. The states are changed in the order of Q0. In the normal state Q0 shown on the upper side of FIG. 5, the master unit 10 takes charge of the master function F1, so that the master unit 10 wirelessly communicates with each of the slave units 20a to 20c.

After that, in the first surrogate state Q1 shown in the upper left of FIG. 5, the first slave unit 20a takes charge of the parent function F1, so that the wireless communication between the master unit 10 and the first slave unit 20a is maintained and the first slave unit 20a is the first. The 2 slave unit 20b and the 3rd slave unit 20c cannot communicate with the master unit 10. After that, in the normal state Q0 shown in the lower left of FIG. 5, the master unit 10 takes charge of the master function F1, so that the wireless communication between the master unit 10 and the first slave unit 20a is maintained and the second slave unit 20b is maintained. And the third slave unit 20c resumes wireless communication with the master unit 10.

After that, in the second surrogate state Q2 shown on the lower side of FIG. 5, the second slave unit 20b takes charge of the parent function F1, so that the wireless communication between the master unit 10 and the second slave unit 20b is maintained and at the same time, the wireless communication between the master unit 10 and the second slave unit 20b is maintained. The first slave unit 20a and the third slave unit 20c cannot communicate with the master unit 10. After that, in the normal state Q0 shown in the lower right of FIG. 5, the master unit 10 takes charge of the master function F1, so that the wireless communication between the master unit 10 and the second slave unit 20b is maintained and the first slave unit is maintained. The 20a and the third slave unit 20c resume wireless communication with the master unit 10.

After that, in the third surrogate state Q3 shown in the upper right of FIG. 5, the third slave unit 20c takes charge of the parent function F1, so that the wireless communication between the master unit 10 and the third slave unit 20c is maintained and the third slave unit 20c is third. The first slave unit 20a and the second slave unit 20b cannot communicate with the master unit 10. After that, in the normal state Q0 shown on the upper side of FIG. 5, the master unit 10 takes charge of the master function F1, so that the wireless communication between the master unit 10 and the third slave unit 20c is maintained and the first slave unit 20a is maintained. And the second slave unit 20b resumes wireless communication with the master unit 10.

FIG. 6 is a time chart when the predetermined order control is performed as described above. When shifting from the normal state Q0 to the first surrogate state Q1, the parent function F1 and the child function f2 are exchanged between the master unit 10 and the first slave unit 20a. As a result, the master unit 10 and the first slave unit 20a maintain wireless communication, and the second slave unit 20b and the third slave unit 20c, which have been wirelessly communicating with the master unit 10 until then, communicate with the master unit 10. It becomes impossible.

After that, when shifting from the first surrogate state Q1 to the normal state Q0, the child function f2 and the parent function F1 are exchanged between the master unit 10 and the first slave unit 20a, so that the parent function is replaced. The function F1 returns to the master unit 10, and the slave function f2 returns to the first slave unit 20a. As a result, the master unit 10 and the first slave unit 20a maintain wireless communication, and the second slave unit 20b and the third slave unit 20c resume wireless communication with the master unit 10.

After that, when shifting from the normal state Q0 to the second surrogate state Q2, the parent function F1 and the child function f2 are exchanged between the master unit 10 and the second slave unit 20b. As a result, the master unit 10 and the second slave unit 20b maintain wireless communication, and the first slave unit 20a and the third slave unit 20c, which had been wirelessly communicating with the master unit 10 until then, communicate with the master unit 10. It becomes impossible.

After that, when shifting from the second surrogate state Q2 to the normal state Q0, the child function f2 and the parent function F1 are exchanged between the master unit 10 and the second slave unit 20b, so that the parent function is replaced. The function F1 returns to the master unit 10, and the slave function f2 returns to the second slave unit 20b. As a result, the master unit 10 and the second slave unit 20b maintain wireless communication, and the first slave unit 20a and the third slave unit 20c resume wireless communication with the master unit 10.

After that, when shifting from the normal state Q0 to the third surrogate state Q3, the parent function F1 and the child function f2 are exchanged between the master unit 10 and the third slave unit 20c. As a result, the master unit 10 and the third slave unit 20c maintain wireless communication, and the first slave unit 20a and the second slave unit 20b, which had been wirelessly communicating with the master unit 10 until then, communicate with the master unit 10. It becomes impossible.

After that, when shifting from the third surrogate state Q3 to the normal state Q0, the child function f2 and the parent function F1 are exchanged between the master unit 10 and the third slave unit 20c, so that the parent function is replaced. The function F1 returns to the master unit 10, and the slave function f2 returns to the third slave unit 20c. As a result, the master unit 10 and the third slave unit 20c maintain wireless communication, and the first slave unit 20a and the second slave unit 20b resume wireless communication with the master unit 10.

Next, a specific example of equalization control will be described with reference to FIG. In this equalization control, the states are changed in the order different from the broken line arrow shown in FIG. For example, when the charge amount of the first battery group 44a is larger than the charge amount of the second battery group 44b and the third battery group 44c, the normal state Q0 → FIG. 5 shown on the upper side of FIG. 5 is used as equalization control. The repeating state is changed in the order of the first surrogate state Q1 shown in the upper left of FIG. As a result, it is estimated that the charge amount of the first battery group 44a is reduced and the charge amount is substantially equal to the charge amount of the second battery group 44b and the third battery group 44c. conduct.

Further, for example, when the charge amount of the first battery group 44a is larger than the charge amount of the second battery group 44b and the charge amount of the second battery group 44b is larger than the charge amount of the third battery group 44c. The equalization control is controlled as follows. That is, the normal state Q0 shown on the upper side of FIG. 5 → the first surrogate state Q1 shown on the upper left of FIG. 5 → the normal state Q0 shown on the lower left of FIG. The repeating state is changed in the order of the normal state Q0 shown on the upper side of. Then, at this time, the period of the first surrogate state Q1 is made longer than the period of the second surrogate state Q2. As a result, the charge amount of the first battery group 44a is reduced, the charge amount of the second battery group 44b is smaller than that, and the charge amount of the first battery group 44a and the second battery group 44b is reduced to that of the third battery group. When it is estimated that the charge amount of 44c is substantially equal to that of the charge amount, the above-mentioned predetermined order control is performed thereafter.

According to this embodiment, the following effects can be obtained. In each of the proxy states Q1 to Q3, the slave unit 20 other than the slave unit 20 responsible for the parent function F1 cannot wirelessly communicate with any of the slave unit 20 and the master unit 10 responsible for the parent function F1. .. However, after that, before the communication connection between the other slave unit 20 and the master unit 10 is interrupted, the normal state Q0 is reached, so that the wireless communication between the other slave unit 20 and the master unit 10 is resumed. Therefore, it is not necessary for the other slave units 20 to change the communication connection from the master unit 10 to the slave unit 20 that bears the master function F1, and each slave unit 20a to 20c can maintain the communication connection with the master unit 10. can. Therefore, when the stopped state Q is changed to the operating state P, each slave unit 20 can promptly start communication with the master unit 10 by the communication connection with the master unit 10 that is maintained.

Further, in the stopped state Q, each slave unit 20 is conditioned that wireless communication with the master unit 10 is not performed for the second interruption determination time or longer, which is longer than the first interruption determination time, which is the interruption determination time in the operating state P. In addition, it is determined that the communication connection with the master unit 10 is interrupted. Therefore, in the stopped state Q, each slave unit 20 can maintain the communication connection with the master unit 10 while prolonging the time during which wireless communication with the master unit 10 is not performed. Therefore, each of the proxy states Q1 to Q3 can be maintained for a long time, and the power consumption by the master unit 10 can be suppressed more efficiently. However, if the time during which wireless communication with the master unit 10 is not performed is made too long, the response when the state is changed from the stopped state Q to the operating state P will be poor, so it is necessary to lengthen the time within an appropriate range. There is.

[Other Embodiments]
The embodiment shown above can be modified and implemented as follows. For example, in each embodiment, the number of slave units 20 is three, but it may be two or four or more.

Further, for example, in each embodiment, in the stopped state Q, either one of the predetermined order control and the equalization control is selectively performed depending on the situation. Instead, for example, the stopped state Q is performed. Then, the predetermined order control may always be performed.

Further, for example, in each embodiment, when the power switch 50 of the vehicle is OFF, the electric devices 91 and 92 are always in the stopped state Q, but instead of this, for example, when the power switch 50 of the vehicle is OFF. , The electric devices 91 and 92 may be brought into the operating state P at a predetermined cycle. Further, for example, in each embodiment, the equalization control is performed based on the charge amount of each battery group 44, but the equalization control may be performed based on the voltage of each battery group 44.

Further, for example, the rotation in charge of the parent function F1 in the stopped state Q of the first embodiment includes the master unit 10, but instead, the rotation includes only the slave unit 20 and is a parent. The machine 10 may always carry out the child function f2 in the stopped state Q. In this case, the power consumption by the master unit 10 can be further suppressed.

Further, for example, in each embodiment, the electric devices 91 and 92 are mounted on the vehicle, but may be mounted on a vehicle, an article, or the like other than the vehicle. Further, for example, in each embodiment, the electric devices 91 and 92 are battery monitoring systems, but may be other electric devices.

Specifically, for example, the electrical devices 91 and 92 may be a tire pressure monitoring system (TPMS). In this case, the slave unit is installed for each tire and acquires tire pressure information which is information on the tire pressure from the tire corresponding to itself. Then, the master unit acquires tire pressure information from each slave unit by wireless communication. In this case, the master unit is supplied with power from, for example, a battery mounted on the vehicle. On the other hand, each slave unit is supplied with power from, for example, each battery installed in each tire or in itself.

10 ... Master unit, 20 ... Slave unit, 20a ... 1st slave unit, 20b ... 2nd slave unit, 20c ... 3rd slave unit, 91, 92 ... Electrical equipment, F1 ... Parent function, f2 ... Child function, P ... Operating state, Q ... stopped state, Q1 ... first surrogate state, Q2 ... second surrogate state, Q3 ... third surrogate state.

Claims (13)

In the operating state (P) in which a master unit (10) and a plurality of slave units (20a to 20c) are provided and predetermined information is exchanged between the master unit and the slave unit by wireless communication. An electric device that maintains the communication connection of the wireless communication by the master unit having a predetermined parent function (F1) and each slave unit having a child function (f2) that consumes less power than the master function. In
In the stopped state (Q) in which the predetermined information is not passed between the master unit and the slave unit, the slave unit takes on the parent function and the master unit performs the child at least for a predetermined period. An electric device that maintains the communication connection while suppressing power consumption by the master unit as compared with the case where the master unit always performs the master function by being in a proxy state (Q1 to Q3) that bears the function. The electric device according to claim 1, wherein at least in the stopped state, the master unit is supplied with power from a predetermined power source (30), and the slave unit is supplied with power from a power source (40) different from the predetermined power source. .. At least in the stopped state, each of the slave units is powered by a separate power source (44a to 44c).
The electric device according to claim 1 or 2, wherein in the stopped state, a plurality of the slave units take turns taking charge of the parent function. The ratio of the time during which one slave unit takes on the parent function within a predetermined unit time is defined as the parent function charge rate of the slave unit.
The electric device according to any one of claims 1 to 3, wherein each of the slave units has its own parent function charge rate changed based on the situation of its own power source (44) as a power source for supplying power to itself. In each of the slave units, the rate of charge for the parent function is higher in the slave unit in which the charge amount of the own power source is larger than the predetermined amount than in the slave unit in which the charge amount of the own power source is a predetermined amount. The electric device according to claim 4, wherein the amount of charge of the power supply that supplies power to each of the slave units is equalized. The electric device according to claim 4 or 5, wherein each slave unit does not carry out the parent function when the charge amount of the self-power supply is less than a predetermined threshold value. In the stopped state, the plurality of slave units carry out the parent functions in a predetermined order.
When the stopped state is changed to the operating state, the predetermined order is interrupted, the master unit takes on the parent function, and the interrupted timing in the predetermined order is stored.
The electric device according to any one of claims 1 to 6, wherein when the operating state is changed to the stopped state, the slave unit sequentially takes on the parent function in the continuation of the predetermined order based on the memory. .. In the proxy state, the slave unit carrying the parent function and the master unit perform wireless communication, and the slave unit carrying the parent function and the other slave unit perform wireless communication. The electrical equipment according to any one of the above. In the proxy state, while the slave unit carrying the parent function and the master unit perform wireless communication, wireless communication between the master unit and another slave unit as the slave unit other than the slave unit carrying the parent function. Is disabled, and then, before the communication connection between the other slave unit and the master unit is interrupted, the master unit enters the normal state (Q0) in which the master unit takes on the master function, so that the other slave unit is in a normal state (Q0). The electric device according to any one of claims 1 to 7, wherein wireless communication between the device and the master unit is resumed. In the operating state, each of the slave units determines that the communication connection with the master unit has been interrupted, provided that wireless communication with the master unit is not performed for the predetermined first interruption determination time or longer.
In the stopped state, the communication connection with the master unit is interrupted on condition that each slave unit does not perform wireless communication with the master unit for the second interruption determination time, which is longer than the first interruption determination time. The electric device according to claim 9, wherein it is determined that the device has been used. The electric device is an in-vehicle device mounted on a vehicle, and is in the operating state when the power switch (50) of the vehicle is turned on, and is in the stopped state when the power switch is turned off. The electrical device according to any one of 10 to 10. The electric device is a battery monitoring system that monitors an assembled battery (40) having a plurality of cell batteries (45).
The slave unit is installed for each battery group (44a to 44c) in which a plurality of the cell batteries are grouped, and obtains battery information which is information about the cell battery from the battery group corresponding to the slave unit.
The master unit acquires the battery information as the predetermined information from each slave unit by wireless communication.
The electrical device according to any one of claims 1 to 11. The electric device according to claim 12, wherein the master unit is supplied with power from an auxiliary battery (30) different from the assembled battery, and each slave unit is supplied with power from the battery group corresponding to the master unit.

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