LoRaWAN + wMBus dual-communication intelligent water meter

Abstract

The invention relates to a LoRaWAN + wMBus dual-communication intelligent water meter, and belongs to the technical field of intelligent communication of water meters. Comprising a main control chip U2 and a dual-mode communication module. The main control chip U2 is an FM33LE026 chip; a chip U1 of the dual-mode communication module is an EWRF 1022MLA; a pin 3 of the chip U1 is connected with a pin 31 of the main control chip U2; a pin 5 of the chip U1 is connected with a pin 32 of the main control chip U2; the system further comprises a power management circuit module, a plurality of peripheral circuit modules and a valve control output circuit module. The power management circuit module is connected with a pin 55 and a pin 56 of the main control chip U2; and the valve control output circuit module is connected with a pin 11 and a pin 12 of the main control chip. The invention provides equipment compatible with LoRaWAN + wMBus dual-mode communication. The functions of static low power consumption, long-distance transmission (about 5km), bidirectional spread spectrum transmission, private protocol communication, OTAA (over-the-air activation) encryption and the like of a LoRaWAN mode are integrated; and meanwhile, the wMBus has the characteristics of frequent transmission and low power consumption of the wMBus.

Description

Technical Field

[0001] This invention relates to a smart water meter with LoRaWAN+wMBus dual communication, belonging to the field of smart water meter communication technology. Background Technology

[0002] Water meters, as devices for measuring water flow, are typically used to measure the cumulative flow of water. To achieve intelligent remote meter reading, the main radio frequency communication methods currently available in the international market are LoRaWAN single-mode communication and wMBus single-mode communication. Very few manufacturers combine both communication modes for wireless meter reading.

[0003] In water meter applications, considering the lifespan of the water meter, LoRaWAN single-mode communication typically selects Class A mode. In this mode, the water meter uploads data at specified intervals, limiting the number of uploads per day to reduce power consumption. When the management platform needs to issue control commands, it must first send them to the network server platform. Once the device is online, the network server platform automatically sends the data. Real-time data interaction between the platform and the device is not possible. (This also means that remote time synchronization functionality is essentially unavailable.) In water meter applications, wMBus single-mode communication typically uses the T1 / C1 frequent transmission mode. This mode allows for frequent data transmission over short distances (approximately 200 meters), but it cannot send data to the device. The distance is significantly reduced when there are obstructions, making this method unsuitable for platform synchronization management (data collected from different areas varies considerably in time). Furthermore, this communication method can only adhere to the EN13757 communication standard format, making it difficult to add monitoring data content according to customer needs. Summary of the Invention

[0004] The purpose of this invention is to provide a smart water meter with LoRaWAN + wMBus dual communication, which simultaneously possesses the functions of LoRaWAN mode, such as static low power consumption, long-distance transmission, bidirectional spread spectrum transmission, private protocol communication, and OTAA (over-the-air) encryption; and the frequent low power consumption characteristics of wMBus.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A smart water meter with LoRaWAN+wMBus dual communication includes a main control chip U2 and a dual-mode communication module; The main control chip U2 is FM33LE026; the dual-mode communication module chip U1 is EWRF 1022MLA. Pin 3 of chip U1 is connected to pin 31 of main control chip U2; pin 5 of chip U1 is connected to pin 32 of main control chip U2. It also includes a power management circuit module, several peripheral circuit modules, and a valve control output circuit module; The power management circuit module is connected to pins 55 and 56 of the main control chip U2; The valve control output circuit module is connected to pins 11 and 12 of the main control chip.

[0006] A further improvement to the technical solution of the present invention is that the power management circuit module includes a working power supply voltage regulator circuit, a reporting power supply voltage regulator circuit, and a device power supply voltage detection circuit.

[0007] A further improvement to the technical solution of the present invention is as follows: the working power supply voltage regulator circuit uses chip U23 as S-1206B33-U3T1U; the reporting power supply voltage regulator circuit uses chip U9 as U23 as S-1206B33-U3T1U; A further improvement to the technical solution of the present invention is that the peripheral circuit module includes an analog sampling reference voltage circuit, an undervoltage protection circuit, a cover opening detection circuit, a multi-channel pulse detection and disconnection detection circuit, and a capacitive button detection circuit.

[0008] A further improvement to the technical solution of this invention is as follows: the analog sampling reference voltage circuit is connected to pin 54 of the main control chip U2; the undervoltage protection circuit uses chip U8, which is XC61CC2502MR-G, and chip U8 is connected to pin 1 of the main control chip U2; the cover opening detection circuit is connected to pin 62 of the main control chip U2; the multi-channel pulse detection and disconnection detection circuit is connected to pin 30 of the main control chip U2, and also to pins 35, 36, 37, and 38 of the main control chip U2; and the capacitive button detection circuit is connected to pin 4 of the main control chip U2.

[0009] A further improvement to the technical solution of the present invention is as follows: the valve control output circuit module includes a motor operating current sampling circuit and an external interface; the motor operating current sampling circuit uses a chip U7, which is MS3111S, with pin 5 of chip U7 connected to pin 12 of the main control chip U2, and pin 6 of chip U7 connected to pin 11 of the main control chip U2; pin 3 of the external interface is connected to pin 20 of the main control chip U2, and pin 3 of the external interface is connected to pin 21 of the main control chip U2.

[0010] A further improvement to the technical solution of the present invention is as follows: the LoRaWAN communication method of the water meter is as follows: the water meter and the distributed deployment gateway exchange data through spread spectrum technology.

[0011] A further improvement to the technical solution of this invention is as follows: The wMBus communication method of the water meter is as follows: the inspection personnel carry the receiver and handheld device and drive along the prescribed route. At this time, the data sent by all devices in the surrounding area can be displayed on the handheld device; the handheld device can directly upload to the server for data analysis and archiving; when the network signal is poor, the mobile phone stores the data in the form of a table locally and exports the data later.

[0012] Due to the adoption of the above technical solution, the technical effects achieved by this invention are as follows: This invention provides a device compatible with LoRaWAN + wMBus dual-mode communication. Through the dual-mode communication module, it integrates the static low power consumption, long-distance transmission (approximately 5km), bidirectional spread spectrum transmission, proprietary protocol communication, and OTAA (Over-the-Air) encryption functions of LoRaWAN mode; while also possessing the low power consumption characteristics of wMBus. A more scientific mechanism is employed to fully address the drawbacks of both modes of transmission.

[0013] The internal circuit design of this invention is compatible with multiple circuit protection mechanisms, with dual power supply management for system power supply and reporting power supply; dual detection mechanism for motor position detection and motor power supply overcurrent detection; and controllable management design for power supply to external devices (such as capacitive buttons, pulse detection, cover opening detection, etc.).

[0014] This invention makes the data transmission methods of smart water meters more diverse and secure, and can achieve stable data transmission under various conditions. Attached Figure Description

[0015] Figure 1 This is the dual-mode communication module in the water meter circuit of this invention; Figure 2 This is a schematic diagram of the main control chip in the water meter circuit of this invention; Figure 3 This is the power management module in the water meter circuit of this invention; Figure 4 This is the peripheral circuit module in the water meter circuit of this invention; Figure 5 This is the valve control output circuit module in the water meter circuit of this invention; Figure 6 This is a schematic diagram of the LoRaWAN communication network architecture for water meters in this invention; Figure 7 This is a schematic diagram of the data structure for LoRaWAN communication reporting of water meters in this invention; Figure 8 This is a schematic diagram of the wMBus communication network structure of the water meter in this invention; Figure 9 This is a schematic diagram of the discrete data transmission mechanism of the water meter wMBus communication in this invention. Detailed Implementation

[0016] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0017] This invention is a smart water meter with LoRaWAN+wMBus dual communication, featuring both LoRaWAN and wMBus communication modes, achieved through a dual-mode communication module.

[0018] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 The diagram shown is a circuit diagram of the water meter. The dual-mode communication of the water meter is achieved through the cooperation of the main control chip, the dual-mode communication module, and multiple functional circuits.

[0019] Combination Figures 1-5 The water meter's circuit mainly includes a main control chip U2 and a dual-mode communication module. The main control chip U2 is an FM33LE026, and the dual-mode communication module chip U1 is an EWRF 1022MLA. Pin 3 of chip U1 is connected to pin 31 of the main control chip U2; pin 5 of chip U1 is connected to pin 32 of the main control chip U2.

[0020] The water meter's circuit also includes a power management circuit module, several peripheral circuit modules, a valve control output circuit module, and other functional circuit modules.

[0021] The power management circuit module is connected to pins 55 and 56 of the main control chip U2; combined with Figure 3 The power management circuit module includes a working power supply voltage regulator circuit, a reporting power supply voltage regulator circuit, and a device power supply voltage detection circuit. The working power supply voltage regulator circuit uses chip U23, which is S-1206B33-U3T1U; the reporting power supply voltage regulator circuit uses chip U9, which is U23, which is S-1206B33-U3T1U.

[0022] The peripheral circuit module includes an analog sampling reference voltage circuit, an undervoltage protection circuit, a cover opening detection circuit, a multi-channel pulse detection and disconnection detection circuit, and a capacitive button detection circuit. Combined with... Figure 4The analog sampling reference voltage circuit is connected to pin 54 of the main control chip U2; the undervoltage protection circuit uses chip U8, which is XC61CC2502MR-G, and chip U8 is connected to pin 1 of the main control chip U2; the cover opening detection circuit is connected to pin 62 of the main control chip U2; the multi-channel pulse detection and disconnection detection circuit is connected to pin 30 of the main control chip U2, and also to pins 35, 36, 37, and 38 of the main control chip U2; the capacitive button detection circuit is connected to pin 4 of the main control chip U2.

[0023] The valve control output circuit module is connected to pins 11 and 12 of the main control chip. (Combined) Figure 5 The valve control output circuit module includes a motor running current sampling circuit and an external interface. The motor running current sampling circuit uses a chip U7 (MS3111S). Pin 5 of chip U7 is connected to pin 12 of the main control chip U2, and pin 6 of chip U7 is connected to pin 11 of the main control chip U2. Pin 3 of the external interface is connected to pin 20 of the main control chip U2, and pin 3 of the external interface is connected to pin 21 of the main control chip U2.

[0024] The above is a description of the circuit. The connection relationships of other pins in the circuit should be referenced in the attached diagram of the instruction manual. Figures 1-5 It is possible to know.

[0025] The smart water meter in this technical solution supports both LoRaWAN and wMBus communication methods. The LoRaWAN communication method of this water meter is as follows: data exchange between the water meter and the distributed gateway is achieved through spread spectrum technology.

[0026] The water meter uses the following wMBus communication method: the inspection personnel carry the receiver and handheld device and drive along the prescribed route. At this time, the data sent by all devices in the surrounding area can be displayed on the handheld device; the handheld device can directly upload to the server for data analysis and archiving; when the network signal is poor, the handheld device stores the data locally in the form of a table and exports the data later.

[0027] The following is a detailed explanation of the communication method of the water meter. According to the appendix Figure 1 As shown, Figure 1 The marker 1 indicates that the dual-mode water meter can be evenly distributed across different areas. Data is uploaded periodically according to a preset time interval. Figure 1 Mark 2 in the diagram represents a distributed deployment gateway, where devices and gateways exchange data via spread spectrum technology; Figure 1Mark 3 in the diagram represents the Network Server receiving platform. The device and the Network Server platform use OTAA encryption. The Network Server platform verifies the device's DevEUI, AppEUI, and AppKey parameters. It synchronously generates random communication parameters DevAddr, NwkSKey, and AppSKey for encryption and decryption communication with the device. Figure 1 Mark 4 in the diagram represents the application platform. Through the gateway and the NETWORK SERVER platform, the device can communicate directly with the platform, and the protocol can be customized privately.

[0028] To meet the needs of different customers, the water meter collects and freezes data at an hourly interval, freezing 24 data entries per day. To ensure the equipment can operate for more than 6 years on battery power, the frequency of data reporting needs to be limited; therefore, a packet upload mechanism was designed into the transmission protocol—such as... Figure 2 As shown, when the reporting interval is 1 hour, 1 hour of data is uploaded each time, and 24 reports are made per day; when the reporting interval is 2 hours, 2 hours of data is uploaded each time, and 12 reports are made per day, and so on. When the reporting interval is 4 hours, 4 hours of data is uploaded each time, and 6 reports are made per day... The packaging structure is as follows. Figure 2 As shown in the right-hand side.

[0029] In this embodiment, because the LoRaWAN communication of the device is spread spectrum communication, the signal quality will decrease as the distance between the device and the gateway increases or as more obstacles arise between them. To ensure communication quality, LoRaWAN communication increases the spreading factor SF. As the spreading factor increases, the corresponding packet byte count decreases in stages, and excessively long data packets cannot be sent. At this time, the device will automatically reduce the reporting interval and decrease the packet size according to the corresponding byte limit to ensure that the reported data can be sent normally.

[0030] In this embodiment, because the LoRaWAN communication mechanism of the device requires a subsequent upload from the device before data can be successfully transmitted (i.e., the data received by the device in this instance may be data transmitted from the center several hours ago), devices in different time zones generally cannot perform automatic time synchronization. Therefore, a differential time synchronization function is added to the device, such as... Figure 2-3As shown, the protocol stipulates that each data transmission includes the device's upload time stamp (TpE) and the platform's local real-time (TpS). These two times occur almost simultaneously, possessing real-time and simultaneity. When the device reports again and receives the data, it can determine its time difference with the local time based on the time difference between these two time stamps, thus adjusting its current time accordingly. However, the device also needs to address another issue—the report record before the time adjustment still has a time difference with the central time. Therefore, the received time stamp after the re-upload still has a significant deviation, even though the time was automatically adjusted previously. Thus, it's necessary to filter out the second response command after the time modification to ensure that the device's time doesn't continuously and overlappingly change. The device clock is precisely calibrated to have a daily error of less than 1 second. Considering that the time may become misaligned over time, but remains within a reasonable range, frequent time adjustments are not advisable. Therefore, the protocol stipulates that the time adjustment function will only be triggered when the time difference exceeds ±5 minutes.

[0031] In this embodiment, because LoRaWAN communication is bidirectional, it enables the management of device parameters and the control of valve components, providing administrators with effective remote valve control management. To ensure that valve opening is triggered in real time after user payment (rather than requiring hourly reporting), the device can be triggered online promptly via button coding to obtain valve opening commands. Therefore, this design ensures both the administrator's management rights and the timely access to water for users.

[0032] In this embodiment, while LoRaWAN communication has many advantages, it also has its drawbacks, being easily affected by external factors such as obstruction and weather. To ensure remote monitoring and management of device data, the device also supports wMBus communication monitoring mode. For example... Figure 3 The diagram shows the overall architecture of wMBus communication. Figure 3 Mark 1 indicates that multiple devices are constantly transmitting; in this mode, device power consumption can still be reduced to below 50µA. Inspection personnel can carry receivers and handheld devices (such as…). Figure 3 As shown in marker 2, drive along the prescribed route, and data from all surrounding devices will be displayed on the handheld device. The handheld device can then directly upload data to the server for analysis and archiving (e.g., ...). Figure 3 (As shown in marker 3); when the network signal is poor, the mobile phone can also store the data locally in table format for easy data export later (e.g., Figure 3 (as shown by marker 4 in the diagram).

[0033] In this embodiment, all devices normally operate in frequent WMBus communication mode. However, if multiple devices upload data simultaneously, the receiver can only respond to the first device, and data from the remaining devices cannot be received correctly. Therefore, a new "discrete centering mechanism" transmission mode is added to the devices. Figure 4 As shown, the device sends data at a time interval of 10 seconds. Figure 4 (Mark 1 is a parallel line). Every 10 seconds, the device sets and sends a marker. At this time, the device's discrete mechanism generates a time stamp with a random range of ±6 seconds and a precision of 0.1 seconds, which is accumulated in the trigger event. Figure 4 As shown in the bar chart marked 2, the data reporting time interval is represented by the "discrete centralization mechanism," where all times are randomly distributed on both sides of the set reporting interval. This mechanism effectively prevents multiple wMBus devices from reporting simultaneously, allowing this communication mode to monitor the data uploaded by all peripheral devices in real time.

[0034] In this embodiment, the power supply is managed under a dual power supply system for both the system and the reporting system. Figure 5 The part marked 2 is the working power supply voltage regulator circuit. Figure 5 The section marked 3 in the diagram represents the reporting power supply regulation circuit. During the reporting process, the main circuit voltage may fluctuate. To ensure the stability of the system's operating voltage, the two power supplies are separated, ensuring that the signal strength during reporting has no impact on the system's power supply. For example... Figure 5 The part marked 1 is the system power supply voltage detection circuit.

[0035] In this embodiment, as Figure 6 It is a dual-mode communication circuit module; it also includes peripheral circuits, such as status indicators and hardware reset circuits.

[0036] In this embodiment, as Figure 7 A collection of peripheral circuits for the system. Figure 7 The part marked 1 is the analog sampling reference voltage circuit, which can provide a 2.5V reference voltage for analog-to-analog conversion. The analog sampling will be precisely calibrated in conjunction with the system algorithm later. Figure 7 The part marked 2 is the undervoltage protection circuit. When the system voltage is lower than 3.0V, some peripherals will not work properly. At this time, the chip generates a reset signal and the system is reset. Figure 7 The part marked 3 is the cover opening detection circuit, which can effectively prevent and monitor equipment damage. Figure 7 The section marked 4 is the multi-channel pulse detection and disconnection detection circuit, which can realize counting modes such as "single pulse, double pulse, and triple pulse" depending on the configuration. "Single pulse" counting can realize high-speed counting function with a detection pulse width of <100us; "double pulse and triple pulse" counting can effectively prevent over-counting caused by jitter, and at the same time, through multi-touch detection, it can determine whether there is magnetic attack interference; "triple pulse" counting can realize the forward and reverse counting function of water meter. Figure 7 The part marked 5 is the capacitive button detection circuit, which can flexibly adjust the level state after the detection event.

[0037] Figure 7The circuits marked 3, 4, and 5 are all powered by controlled power supplies. Figure 7 The PMOS transistor in section 4 is used to control the device and prevent it from failing due to abnormal conditions.

[0038] In this embodiment, as Figure 8 This is the motor control circuit. Circuit 8-1 is the motor operating current sampling circuit. When the analog sample value is <10, it is considered no-load, indicating no motor input; when the analog sample value is >150, it is overload, indicating the valve is in position or the motor is stalled. This design can be used for two-wire motor control, while also preventing long-term motor stalling caused by malfunctioning electric shock detection in five-wire systems. To improve the compatibility of motor control, combined with... Figure 8 The part marked 2 has a 5-wire peripheral interface design, with newly added normally open (NO), normally closed (NC), and common (GND) interfaces, which can quickly stop the power supply to the motor through timely electric shock detection.

[0039] This invention provides a device compatible with LoRaWAN + wMBus dual-mode communication, integrating the static low power consumption, long-distance transmission (approximately 5km), bidirectional spread spectrum transmission, proprietary protocol communication, and OTAA (over-the-air) encryption functions of LoRaWAN mode; while also possessing the frequent low power consumption characteristics of wMBus. A more scientific mechanism is employed to fully address the drawbacks of both modes of transmission.

[0040] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A smart water meter with LoRaWAN+wMBus dual communication, characterized in that: Including the main control chip U2 and the dual-mode communication module; The main control chip U2 is FM33LE026; the dual-mode communication module chip U1 is EWRF 1022MLA. Pin 3 of chip U1 is connected to pin 31 of main control chip U2; pin 5 of chip U1 is connected to pin 32 of main control chip U2. It also includes a power management circuit module, several peripheral circuit modules, and a valve control output circuit module; The power management circuit module is connected to pins 55 and 56 of the main control chip U2; The valve control output circuit module is connected to pins 11 and 12 of the main control chip.

2. The smart water meter with LoRaWAN+wMBus dual communication as described in claim 1, characterized in that: The power management circuit module includes a working power supply voltage regulator circuit, a reporting power supply voltage regulator circuit, and a device power supply voltage detection circuit.

3. A smart water meter with LoRaWAN+wMBus dual communication as described in claim 2, characterized in that: The working power supply voltage regulator circuit uses chip U23, which is S-1206B33-U3T1U; the reporting power supply voltage regulator circuit uses chip U9, which is U23, which is S-1206B33-U3T1U.

4. The smart water meter with LoRaWAN+wMBus dual communication as described in claim 1, characterized in that: The peripheral circuit module includes an analog sampling reference voltage circuit, an undervoltage protection circuit, a cover opening detection circuit, a multi-channel pulse detection and disconnection detection circuit, and a capacitive button detection circuit.

5. A smart water meter with LoRaWAN+wMBus dual communication as described in claim 4, characterized in that: The analog sampling reference voltage circuit is connected to pin 54 of the main control chip U2; the undervoltage protection circuit uses chip U8, which is XC61CC2502MR-G, and chip U8 is connected to pin 1 of the main control chip U2; the cover opening detection circuit is connected to pin 62 of the main control chip U2; the multi-channel pulse detection and disconnection detection circuit is connected to pin 30 of the main control chip U2, and also to pins 35, 36, 37, and 38 of the main control chip U2; the capacitive button detection circuit is connected to pin 4 of the main control chip U2.

6. A smart water meter with LoRaWAN+wMBus dual communication as described in claim 1, characterized in that: The valve control output circuit module includes a motor operating current sampling circuit and an external interface. The motor operating current sampling circuit uses a chip U7 (MS3111S). Pin 5 of chip U7 is connected to pin 12 of the main control chip U2, and pin 6 of chip U7 is connected to pin 11 of the main control chip U2. Pin 3 of the external interface is connected to pin 20 of the main control chip U2, and pin 3 of the external interface is connected to pin 21 of the main control chip U2.

7. A smart water meter with LoRaWAN+wMBus dual communication according to any one of claims 1-6, characterized in that: The water meter uses the following LoRaWAN communication method: the water meter exchanges data with the distributed gateways via spread spectrum technology.

8. A smart water meter with LoRaWAN+wMBus dual communication according to any one of claims 1-6, characterized in that: The water meter uses the following wMBus communication method: the inspection personnel carry the receiver and handheld device and drive along the prescribed route. At this time, the data sent by all devices in the surrounding area can be displayed on the handheld device; the handheld device can directly upload to the server for data analysis and archiving; when the network signal is poor, the handheld device stores the data locally in the form of a table and exports the data later.

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