WO2021250764A1

WO2021250764A1 - Wireless connection method for bluetooth device

Info

Publication number: WO2021250764A1
Application number: PCT/JP2020/022610
Authority: WO
Inventors: 宏明大西
Original assignee: 三菱電機株式会社
Priority date: 2020-06-09
Filing date: 2020-06-09
Publication date: 2021-12-16
Also published as: JP6976463B1; JPWO2021250764A1

Abstract

The present invention causes an advertising frame (AF) interval of a first device (4a to 4c), which corresponds to a Bluetooth device, to change for a certain period of time, and a change of the interval is detected by a second device (1), whereby wireless connection between the first device (4a to 4c) and the second device (1) can be established preferentially. Accordingly, it is possible to establish connection with a necessary Bluetooth device quickly and simply.

Description

Wireless connection method for Bluetooth devices

This application relates to a wireless connection method for Bluetooth (Bluetooth is a registered trademark) device.

For example, in the method of connecting (pairing) a mobile phone and a speaker that is a Bluetooth device, if a speaker (peripheral) is placed near the mobile phone (central), the mobile phone on the host side will check the speaker and confirm it. It is connected by the user selecting this speaker on the screen displaying what has been done. Anyone can easily connect by such a connection method (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2018-85773

On the other hand, electric power measuring devices such as watt-hour meters often do not have a display screen or an input device. In addition, the protection relay that is connected to the measuring device and cuts off the current when the measuring device detects an overcurrent has only a simple display device and several button-type input units. Therefore, when making settings for connecting the protection relay and the measuring device via Bluetooth, in order to make the protection relay recognize the address of a specific measuring device from among multiple measuring devices, the protection relay is used as a personal computer (PC). ) Is required to register the address, which causes problems such as time and effort.

The present application has been made to solve the above-mentioned problems, and aims to provide a method that can be easily connected to a Bluetooth device to be preferentially connected.

The wireless connection method of the Bluetooth device disclosed in the present application changes the period of the advertisement frame of the first device for a certain period of time, and after the change of this cycle is detected by the second device, the first device and the first device are used. It is characterized by making a wireless connection for transmitting / receiving data to / from the device of 2.

According to the wireless connection method of the Bluetooth device disclosed in the present application, the period of the advertisement frame of the first device to be connected to the second device is changed for a certain period, so that the device can be easily connected to the first device. A wireless connection for sending and receiving data can be made.

It is a circuit block diagram which connected the measuring instrument and the protection relay which concerns on Embodiment 1. FIG. It is a functional block diagram of the measuring instrument and protection relay which concerns on Embodiment 1. FIG. It is a figure which shows the display operation part of the protection relay which concerns on Embodiments 1 to 3. It is a hardware block diagram of the control part which concerns on Embodiment 1. FIG. It is a flowchart explaining the connection method of the measuring instrument and a protection relay which concerns on Embodiment 1. FIG. It is a figure explaining the transmission cycle of an advertisement frame. It is a figure explaining the address display of the measuring instrument which concerns on Embodiment 1. FIG. It is another figure explaining the address display of the measuring instrument which concerns on Embodiment 1. FIG. It is a flowchart explaining the connection method of the measuring instrument and a protection relay which concerns on Embodiment 2. It is a functional block diagram of the measuring instrument and protection relay which concerns on Embodiment 3. FIG. It is a flowchart explaining the connection method of the measuring instrument and a protection relay which concerns on Embodiment 3.

Embodiment 1.
Hereinafter, a preferred embodiment of the wireless connection method for the Bluetooth device according to the present application will be described with reference to the drawings. The same contents and corresponding parts are designated by the same reference numerals, and detailed description thereof will be omitted. Similarly, in the subsequent embodiments, duplicate description of the configurations with the same reference numerals will be omitted.

FIG. 1 is a circuit configuration diagram when applied to a protection relay 1 and measuring instruments 4a to 4c as a Bluetooth device of the wireless connection method according to the first embodiment. Transformers 3a to 3c to be protected are connected to the power system power supply (not shown) via circuit breakers 2a to 2c (CB: Circuit Breaker). Further, measuring instruments 4a to 4c such as a current transformer (CT: Circuit Transferr) for extracting an alternating current for each phase are provided between the circuit breakers 2a to 2c and the transformers 3a to 3c. The low voltage side of the transformers 3a to 3c is connected to the load via a no-fuse breaker (MCCB: Molded Case Circuit Breaker) 5. The AC current measurement data measured by the measuring instruments 4a to 4c is transmitted to the protection relay 1, and the circuit breakers 2a to 2c are cut off by the open / close signal of the protection relay 1 for protection from the overcurrent generated due to a system failure or the like. It operates and the transformers 3a to 3c are protected.

FIG. 2 is a functional block diagram of the protection relay 1 and the measuring instruments 4a to 4c in the first embodiment. FIG. 2A shows a functional block diagram of the protection relay 1, and FIG. 2B shows a functional block diagram of the measuring instruments 4a to 4c. Here, the measuring instrument 4a will be described, but the

measuring instruments

4b and 4c have the same configuration. The alternating current Iw is converted into an appropriate size by the current measuring unit 41 of the measuring instrument 4a. The A / D conversion unit 42 samples the alternating current converted by the current measurement unit 41 at regular time intervals, and transmits the measured value from the transmission / reception unit 43 to the protection relay 1.

The protection relay 1 receives the current value from the measuring instrument 4a in the transmission / reception unit 11, and performs statistical processing such as calculation of the average value of the received current values in the arithmetic processing unit 12, for a certain period of time or a certain number of times or more. When an overcurrent flows, the control unit 13 gives a cutoff instruction to the circuit breaker 2a.

FIG. 3 is a diagram showing an image example of the display operation unit 1a of the protection relay 1. The indicator lamp 6 indicates the operating state by lighting or blinking, respectively, and the circuit breaker ON lamp 6a is turned on when the circuit breakers 2a to 2c are turned on. The circuit breaker OFF lamp 6b is turned on when the circuit breakers 2a to 2c are opened. The overcurrent protection function operation lamp 6c blinks when the circuit breakers 2a to 2c are opened by the protection operation when a fault current occurs. The system abnormality lamp 6d lights up when an abnormality occurs in the protection relay 1. The switch 7 is a switch that turns on and off the operation of the device, and the switch 7a turns on the circuit breakers 2a to 2c. The switch 7b opens the circuit breaker. The switch 7c is a remote switch for performing remote control. The switch 7d is a reset switch for resetting the abnormal state of the protection relay. The display unit 14 displays a quantitative numerical value of each operation, an address of the connected measuring instrument, and the like. Further, as described in the third embodiment, the speaker 8 may be provided.

Transmission and reception between the protection relay 1 and the measuring instruments 4a to 4c conforms to the Bluetooth standard, and in particular, conforms to the standard format of Bluetooth Low Energy (Bluetooth Low Energy is a registered trademark, hereinafter referred to as BLE). Control related to BLE is performed by the control unit 13 of the protection relay 1 and the control unit 44 of the measuring instruments 4a to 4c.

FIG. 4 shows an example of the hardware configuration of the microcomputers of the control unit 44 and the control unit 13 mounted on the measuring instruments 4a to 4c and the protection relay 1. It is composed of a processor 100 and a storage device 200, and although not shown, the storage device includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory. Further, the auxiliary storage device of the hard disk may be provided instead of the flash memory. By executing the program input from the storage device 200, the processor 100 controls, for example, the above-mentioned operation or the transmission / reception described below. In this case, a program is input from the auxiliary storage device to the processor 100 via the volatile storage device. Further, the processor 100 may output data such as a calculation result to the volatile storage device of the storage device 200, or may store the data in the auxiliary storage device via the volatile storage device. Further, a plurality of processors 100 and storage devices 200 may exist.

[Registration of measuring instrument address]
The protection relay 1 needs to register the address of each measuring instrument in order to identify which of the measuring instruments 4a to 4c the information is from. In BLE, 48 bits are allocated as an address for specifying each measuring instrument 4a to 4c. The 48 bits to be allocated are set in the advertisement frame determined by the BLE standard. This advertisement frame is transmitted from each of the measuring instruments 4a to 4c so that the measuring instruments 4a to 4c are identified by the protection relay 1. For example, when the protection relay 1 is within the range in which the advertisement frame of the measuring instrument 4a can be received, the address in the advertisement frame received by the protection relay 1 is read out, and the control unit 13 displays the existence of the measuring instrument 4a. can do.

The cycle in which the measuring instrument 4a can transmit an advertisement frame can be set as an integral multiple of 0.625 milliseconds from 20 milliseconds to 10.24 seconds. For example, assuming that the protection relay side tries to connect for 30 seconds after turning on the power of the measuring instrument 4a, transmission is performed at intervals of 20 milliseconds, and if the connection is not established, the transmission cycle is gradually lengthened thereafter for measurement. Although it takes some time to discover the vessel 4a, it is possible to preset the cycle interval, such as suppressing power consumption.

By forcibly changing the period of the advertising frame of the measuring instrument 4a by utilizing the characteristic of BLE that can make the period of the advertising frame variable, the protection relay 1 quickly recognizes the measuring instrument 4a. You can register the address. This will be described in detail below with reference to the flowchart of FIG.

Before arranging the measuring instrument 4a in the above-mentioned power distribution equipment, it is necessary to register the address of the measuring instrument 4a in the protection relay 1. Therefore, for example, the protection relay 1 and the measuring instrument 4a are brought close to each other to register the address. The details of the registration are described below.

First, the power of the measuring instrument 4a is turned on, and an advertised frame AF having a fixed period t as shown in FIG. 6A is transmitted (step S10 in FIG. 5).

When the advertisement frame AF is transmitted in the cycle t of the protection relay 1, the address 04a of the measuring instrument 4a is displayed on the display unit 14 as shown in FIG. On the display unit, the addresses of BLE devices other than the measuring instrument 4a that can be received by the protection relay 1 are also displayed at the same time.

Next, as shown in FIG. 2B, by performing a specific operation X such as pressing a switch mounted on the measuring instrument 4a, the control unit 44 shows the period of the advertise frame as shown in FIG. 6B. For example, during the time P, the transmission is performed at a cycle three times the cycle t (step S11).

The shortened advertisement frame cycle is received by the transmission / reception unit 11 of the protection relay 1 for a predetermined time. From the change in the received cycle, the control unit 13 of the protection relay 1 determines that the measuring instrument 4a, which is the source of the received radio wave, indicates the intention of connection, and displays the protection relay 1 as shown in FIG. The address is highlighted in the unit 14, and the operator is made to recognize the confirmation of the connection (step S12). This highlighting can be, for example, enclosing the address in a frame, changing the display color, changing the font, prefixing the address with a symbol such as "*", blinking the address, placing it at the top of the display, or Only the highlighted address is displayed on the display unit 14. Alternatively, a plurality of them may be combined and displayed.

The operator inputs [No], which ignores the confirmation, to the protection relay 1 or leaves it as it is, indicating that there is no intention of connection, and the protection relay 1 indicates data with the measuring instrument 4a. The transmission / reception operation is not started (step S13).

When the operator inputs [Yes] to be connected to the protection relay 1, the operation of transmitting / receiving data to / from the measuring instrument 4a is started, and the control unit 13 inputs the address of the measuring instrument 4a and the like to the advertise frame AF. Obtained from the above and stored in the storage device 200 (step S14). This completes the address registration of the measuring instrument 4a. The input of [Yes] may be performed by changing the function of the existing switch 7 (holding down, etc.), and when the display unit 14 is a touch screen, touch on the highlighted address. You may do it.

After that, data such as the measured value of the measuring instrument 4a can be transmitted and received according to the procedure of BLE wireless communication (step S15).

Registration of the address to the protection relay 1 is particularly effective when, for example, only two measuring

instruments

4a and 4c are to be registered instead of all the measuring instruments 4a to 4c among the plurality of measuring instruments 4a to 4c. That is, when the three measuring instruments 4a to 4c are within the range in which the protection relay 1 can receive, if each of the measuring instruments 4a to 4c transmits an advertisement frame in the same cycle, the protection relay 1 can see. After displaying all the addresses 04a to 04c of the measuring instruments 4a to 4c, it is necessary to specify the

addresses

04a and 04c of the two necessary measuring

instruments

4a and 4c. However, by shortening the transmission cycle of the advertisement frame of the measuring

instruments

4a and 4c, as shown in FIG. 8, the protection relay 1 requires the registration of the address, and the

addresses

04a and 04c of the measuring

instruments

4a and 4c are required. Can be highlighted and can be quickly identified.

In the above example, the transmission cycle of the advertisement frame is set short, but the same effect can be obtained by setting the transmission cycle longer for a certain period of time.

The switch mounted on the measuring instruments 4a to 4c for making the transmission cycle of the advertise frame variable is to operate the existing switch by pressing and holding the existing switch or pressing it multiple times within a certain period of time. You may change the function of the switch by changing the method of.

By forcibly changing the transmission cycle of the advertisement frame when registering the address of the measuring instrument in the protection relay as described above, there is no need to connect a device such as a PC externally and register the address. It is possible to easily register the required measuring instrument address in the protection relay in a short time.

In the present embodiment, the measuring instruments 4a to 4c have been described as current transformers, but they may be transformers for measuring instruments, and can be applied even if the current transformer and the transformer for measuring instruments are mixed.

In addition, when multiple BLE devices other than measuring instruments are mixed, for example, when there are multiple display devices, audio devices, input devices, etc., it is also possible to quickly register the address of only the devices that need to be connected. Applicable.

Embodiment 2.
[Registration of measured values in the protection relay]
As shown in FIG. 1, when measuring instruments 4a to 4c are installed in a distribution system and the measuring instruments 4a to 4c measure a current exceeding a predetermined threshold value, the protection relay 1 stores the number of times. Is also applicable. FIG. 9 is a flowchart showing this procedure. Such measured values are useful as data when performing maintenance of the system or maintenance of the measuring instrument itself.

When the measuring instrument 4a measures a current value exceeding a predetermined threshold value among the measuring instruments 4a to 4c (step S20), the transmission cycle of the advertisement frame is forcibly changed (shortened) for a certain period by using this as a trigger. ) (Step S21).

The protection relay 1 detects a change in the transmission cycle of the advertisement frame, confirms the connection with the measuring instrument 4a, and stores the number of times such an event occurs in the protection relay 1 (step S22).

When an event occurs, the address of the detected measuring instrument 4a may be displayed on the display unit 14 of the protection relay 1 to notify the operator (step S23). Further, detailed data such as a current value may be transmitted / received in the connected state (step S24). Further, when the number of detections exceeds a predetermined number of times, a warning may be issued to the operator, or the circuit breaker 2a may be operated after issuing the warning.

As described above, when an unusual event occurs without performing any special operation on the measuring instrument, it is possible to check the connection status between the protection relay and the measuring instrument and memorize the number of occurrences of that event. It can be used as useful data when maintaining the system or measuring instrument.

Embodiment 3
[Display of measuring instrument abnormality protection relay]
Hereinafter, the third embodiment according to the present application will be described. As shown in FIG. 10A, the measuring instruments 4d to 4f have a self-diagnosis unit 44a for performing a self-diagnosis in addition to the functions of the measuring instruments 4a to 4c of the first embodiment. Further, as shown in FIG. 10B, the protection relay 1 has a display unit 14 that can display the self-diagnosis results of the measuring instruments 4d to 4f, and a speaker 15 that warns the operator to register. Hereinafter, the measuring instrument 4d will be described with reference to the flowchart of FIG.

The self-diagnosis function is, for example, when a specific operation Y is performed such as pressing a switch mounted on the measuring instrument 4d (step S30), the measuring instrument 4d performs a self-diagnosis before transmitting an advertisement frame. Start (step S31).

Specifically, for example, when a current Id of a predetermined magnitude is applied to the measuring instrument 4d, whether or not the current value measured by the current measuring unit 41 correctly measures the current Id of the predetermined magnitude. Is diagnosed by the self-diagnosis unit 44a (step S32).

If the measurement is correct and the diagnosis is normal, an advertisement frame having a period t is transmitted from the transmission / reception unit 43, and the operations described in steps S11 to S15 of the first embodiment are performed as necessary. (Step S33).

If the measurement is not performed correctly and an abnormality is diagnosed, the control unit 44 determines that there is an abnormality in the current measurement unit 41 or the A / D conversion unit 42, and changes to a cycle different from the cycle t transmitted at normal time. Then, an advertise frame is transmitted (step S34).

The protection relay 1 that has received the advertisement frame changed to a cycle different from the cycle t displays a highlighting different from the highlighting of the address 04d described in the first embodiment on the display unit 14 and displays the highlighting on the display unit 14 and the measuring instrument 4d. It is displayed that there is an abnormality in (step S35). For example, if the display in the operation X is a display in which a frame is attached to the address, the display in the operation Y is a display in which the address is blinked.

Further, when the operator tries to register the measuring instrument 4d having an abnormality, the display unit may display a display indicating that the measuring instrument 4d cannot be registered or a display indicating that the measuring instrument 4d has an abnormality, from the speaker 15. The operator may be notified by a warning sound.

As described above, even if the measuring instrument does not have a display function or a warning function, the abnormality of the measuring instrument can be quickly notified to the protection relay, and the operator can display the abnormal measuring instrument by the display or warning on the protection relay. It is possible to prevent registration in advance.

The self-diagnosis unit 44a may be provided outside the control unit 44. Further, a current having a predetermined magnitude may be applied from the outside or may be generated inside the measuring instrument. Further, there may be a plurality of current values of the predetermined current.

Although the present application describes various exemplary embodiments and examples, the various features, embodiments, and functions described in one or more embodiments are applications of a particular embodiment. It is not limited to, but can be applied to embodiments alone or in various combinations.
Therefore, innumerable variations not exemplified are envisioned within the scope of the techniques disclosed herein. For example, it is assumed that at least one component is modified, added or omitted, and further, at least one component is extracted and combined with the components of other embodiments.

1: Protection relay, 2a, 2b, 2c: Circuit breaker, 3a, 3b, 3c: Transformer, 4a, 4b, 4c: Measuring instrument, 5: No fuse breaker, 11, 43: Transmission / reception unit, 12: Arithmetic processing unit , 13, 44: Control unit, 14: Display unit, 41: Current measurement unit, 42: A / D conversion unit, 100: Processor, 200: Storage device

Claims

After changing the period of the advertise frame of the first device for a certain period and detecting the change in the cycle by the second device, the radio for transmitting and receiving data between the first device and the second device. A wireless connection method for Bluetooth devices, which is characterized by making a connection.
There are a plurality of the first devices, and the wireless connection between the selected device and the second device is performed by changing the period of the advertise frame of the device selected from the plurality of devices for a certain period of time. The wireless connection method for a Bluetooth device according to claim 1.
Claim 1 is characterized in that the second device that has detected the change in the cycle displays an address extracted from the advertisement frame of the first device so that it can be distinguished from the address of another device. How to connect the Bluetooth device wirelessly as described in.
2. The second device that has detected a change in the cycle displays an address extracted from the advertisement frame of the selected device so that it can be distinguished from the address of another device. The wireless connection method of the Bluetooth device described in.
One of claims 1 to 4, wherein the second device is provided with a display unit for notifying the necessity of the wireless connection before the wireless connection for data transmission / reception is performed. The wireless connection method of the Bluetooth device described in.
The wireless of the Bluetooth device according to claim 4 or 5, wherein the second device is provided with a means for determining the necessity of a wireless connection based on an address displayed so as to be identifiable. Connection method.
The wireless connection of the Bluetooth device according to any one of claims 1 to 6, wherein the first device includes a switch for changing the period of the advertise frame for a certain period of time. Method.
The wireless connection method for a Bluetooth device according to claim 1, wherein the number of times the second device detects a change in the cycle is stored.
The first device is a measuring instrument, the second device is a protection relay, and when the measuring instrument detects a current equal to or higher than a predetermined threshold value, the period of the advertised frame is changed for a certain period of time. The wireless connection method for a Bluetooth device according to claim 7 or 8, wherein the protection relay recognizes the address of the measuring instrument and transmits / receives data.
The cycle of the advertisement frame of the first device is changed for a certain period, and after the change of the cycle is detected by the second device, the address extracted from the advertisement frame of the first device is used by another device. A method for wirelessly connecting a Bluetooth device, characterized in that it is displayed on the second device so that it can be identified from the address of the Bluetooth device.
One of claims 1 to 4, and claim 10, wherein when an abnormality is detected in the first device, the period of the advertisement frame of the first device is changed for a certain period of time. The wireless connection method for the Bluetooth device described in paragraph 1.
The wireless connection method for a Bluetooth device according to claim 11, wherein the first device is provided with a self-diagnosis unit for detecting an abnormality.