CN110763292A - Novel ultrasonic intelligent water meter - Google Patents

Abstract

The invention relates to a new type of ultrasonic intelligent water meter, comprising a microcontroller, which is respectively connected to a power supply module, a measurement module, a liquid crystal display module, a voltage detection module, a temperature detection module, a storage module, a valve control module and a communication module , photoelectric switch and infrared communication module, and control them; the photoelectric switch transmits the switch signal to the microcontroller through the change of light irradiated on the water meter cover, triggers the microcontroller to perform switch operation, and is controlled by the microcontroller The liquid crystal display module turns pages, and the microcontroller is equipped with an EEPROM unit. The microcontroller adopts STM32, the temperature detection module adopts DS18B20 temperature sensor, and the communication module includes wired communication and wireless communication. The wired communication adopts M-BUS or 485 bus communication; The microcontroller performs timing data reporting. The present invention has the advantages of low power consumption, wide range ratio, and diversified data communication modes.

Description

A new type of ultrasonic smart water meter

technical field

The invention belongs to the field of intelligent water meters, in particular to a novel ultrasonic intelligent water meter.

Background technique

Smart water meter is a new type of water meter that uses modern microelectronic technology and modern sensing technology to measure water consumption and transmit water consumption data. Compared with traditional water meters, which generally only have the functions of flow collection and mechanical pointer to display water consumption, it is a great improvement. In addition to recording and electronically displaying water consumption, smart water meters can also control water consumption as agreed. The technology of remote transmission and automatic reading system is one direction of the development of smart water meters.

In smart water meters, expanding the measurement range and increasing the service life of the water meters are common requirements for all water meters. Therefore, the ultrasonic water meter is one of the important development directions.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the above problems and provide a new type of ultrasonic intelligent water meter control system with low power consumption, wide range ratio and diversified data communication modes.

To achieve the above object, the present invention provides the following technical solutions:

A new type of ultrasonic smart water meter includes a microcontroller, which is respectively connected to a power supply module, a measurement module, a liquid crystal display module, a voltage detection module, a temperature detection module, a storage module, a valve control module, a communication module, and a photoelectric switch. and infrared communication module, and control it; the photoelectric switch transmits the switch signal to the microcontroller through the change of light irradiated on the water meter cover, triggers the microcontroller to perform the switch operation, and the microcontroller controls the liquid crystal display module Turning the page, the microcontroller is equipped with an EEPROM unit.

Further, the power supply module, the voltage detection module, the temperature detection module and the photoelectric switch are connected to the input end of the microcontroller, the liquid crystal display module is connected to the output end of the microcontroller, the measurement module, the storage module, and the valve control module. , communication module and infrared communication module are bidirectionally connected with microcontroller.

Further, the communication module includes wired communication and wireless communication, and the wired communication adopts M-BUS or 485 bus communication; the wireless communication adopts NB-IOT or LoRa, and reports timing data to the microcontroller.

Preferably, the microcontroller adopts STM32, which is an ARM Cortex-M3 series chip with ultra-low power consumption and high performance, the current in the low-power operation mode is less than 30μA, and the operating voltage is 1.8-3.6V.

Preferably, the power module adopts a 3.6V lithium battery; the measurement module is composed of a TDC_GP22 chip, an ultrasonic probe, a transmission control circuit, and an ultrasonic signal processing circuit; the liquid crystal display module includes a liquid crystal driver and a liquid crystal screen, forming a human-computer interaction interface; the voltage detection module collects the voltage signal through the AD conversion interface of the microcontroller; the temperature detection module adopts the DS18B20 temperature sensor for collecting the real-time temperature of the water flow of the water meter; the storage module adopts a built-in large-capacity Flash chip The valve control module adopts an electric ball valve, and drives the electric ball valve to rotate forward or reverse through a DC motor to control the opening and closing of the valve; the infrared communication module adopts an infrared transmitting tube and an infrared receiving tube, both of which are connected to the microcomputer. on the IO port of the controller.

Compared with the prior art, the beneficial effects of the present invention are:

1) Low power consumption: select a low-power chip suitable for the present invention, turn off the peripheral circuits that consume a lot of power when not in use, set the unused IO ports reasonably, and set the system clock to the internal clock to reduce power consumption , before the system enters low power consumption, the peripheral clocks that are not used will be turned off to reduce power consumption and low power consumption, and the current is less than 30uA.

2) Wide range ratio: STM32-bit microcontroller is used as the core control device of the present invention, which can more accurately measure the propagation time difference of ultrasonic beams in water. Through many experiments, the most suitable configuration mode of GP22 chip is determined to ensure the accuracy of the measured ultrasonic beam propagation time difference in water; a large amount of data is obtained to obtain the law, and the measurement algorithm is realized; due to the propagation speed of ultrasonic waves in water with different temperatures Different, it is necessary to select an accurate functional relationship through testing to ensure that the speed of ultrasonic waves at different water temperatures is calculated correctly.

3) A variety of data communication methods are available: M-BUS or 485 bus communication can be selected for wired remote transmission, which can realize one-to-many transmission mode, greatly reducing the cost of manual meter reading and improving the meter reading rate. The wireless remote transmission can choose NB-IOT or LoRa, and report the data regularly to the microcontroller.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the drawings in the following description are only for the purpose of illustrating the present invention more clearly. For the embodiments or technical solutions in the prior art, for those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

Fig. 1 is the system hardware connection block diagram of the present invention;

2 is a hardware circuit diagram of a peripheral power switch of the present invention;

Fig. 3 is the hardware circuit diagram of infrared communication part of the present invention;

Fig. 4 is the photoelectric switch hardware circuit diagram of the present invention;

Fig. 5 is the electric motor drive hardware circuit diagram of the present invention;

Fig. 6 is the hardware circuit diagram of the measuring part of the present invention;

FIG. 7 is a flow chart of the software implementation of the measurement part of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand that the technical solutions of the present invention can be implemented, the present invention will be further described below in conjunction with specific embodiments, but the given embodiments are only used as descriptions of the present invention, not as limitations of the present invention.

As shown in Figures 1-7, a new type of ultrasonic smart water meter includes a microcontroller 1, which is respectively connected to a power supply module 2, a measurement module 3, a liquid crystal display module 4, a voltage detection module 5, and a temperature detection module. Module 6, storage module 7, valve control module 8, communication module 9, photoelectric switch 10 and infrared communication module 11, and control them; the photoelectric switch 10 communicates with the microcontroller 1 through the change of light irradiated on the water meter cover. The switch signal is transmitted, and the microcontroller 1 is triggered to perform a switch operation, and the microcontroller 1 controls the liquid crystal display module 4 to turn pages, and the microcontroller 1 is provided with an EEPROM unit.

The power module 2, the voltage detection module 5, the temperature detection module 6 and the photoelectric switch 10 are connected to the input end of the microcontroller 1, the liquid crystal display module 4 is connected to the output end of the microcontroller 1, the measurement module 3, the storage The module 7 , the valve control module 8 , the communication module 9 and the infrared communication module 11 are all bidirectionally connected with the microcontroller 1 .

Microcontroller 1 of this system adopts ultra-low power consumption STM32 as the core control device, and controls the modules of signal detection, data processing, liquid crystal display, data storage and communication. It is an ultra-low-power, high-performance ARM Cortex-M3 series chip, the low-power operating mode current is less than 30μA, and the operating voltage is 1.8-3.6V.

The contents of each module in the system are as follows:

Power module 2: A 3.6V lithium battery is used for the power supply of the system. The low-power power conversion chip and filter circuit design ensure reliable and stable operation of the system, and the battery life can reach 6 years.

Measurement module 3: The measurement part consists of TDC_GP22, ultrasonic probe, emission control circuit, ultrasonic signal processing circuit, etc. TDC_GP22 and ultrasonic probe are the main components of the measurement part. TDC_GP22 is a time interval and temperature measurement chip with functions such as high-speed pulse generator, stop signal enable, temperature measurement and clock control. It can be used as an external device and microcomputer through four-wire SPI. Controller 1 is connected. The measurement process is:

TDC_GP22 transmits a high-speed pulse drive signal to two ultrasonic probes, the ultrasonic probe starts to vibrate, and is ready to receive ultrasonic signals. The received ultrasonic signals are amplified and filtered to filter out high-frequency noise to obtain sinusoidal ultrasonic signals. The signals are compared and shaped by zero-crossing Then it is sent to the two stop channels of TDC_GP22. After the two channels respectively receive the transition of the signal, the time interval between the two transitions is measured.

Liquid crystal display module 4: It is mainly composed of liquid crystal driver and liquid crystal screen. The module constitutes a human-computer interaction interface. The liquid crystal is always on and can display information such as cumulative flow, instantaneous flow, real-time time, and battery voltage.

Voltage detection module 5: This system uses a 3.6V lithium battery as the power supply. After a period of use, the battery energy will be lost. In order to ensure the normal operation of the entire system, the voltage signal is collected through the microcontroller 1AD conversion interface. When When the voltage cannot meet the system requirements, the LCD will display a low voltage symbol.

Temperature detection module 6: Since the propagation speed of ultrasonic waves in the water flow is related to the temperature, in order to ensure the accuracy of the measurement time difference, this system adopts the DS18B20 temperature sensor. The time difference is collected, and the real-time temperature of the water flow is collected.

Memory module 7: A large-capacity Flash chip is used as memory in the design to store historical flow, accumulated flow, real-time time, user ID and other information. The EEPROM unit inside the microcontroller 1 can restore data after power down.

Valve control module 8: This part is realized by DC motor, solenoid valve and drive circuit. Valve control is a very sensitive part in the water meter control system. The poor reliability of closing and opening the valve will bring great problems to the water supply department. This system uses an electric ball valve, the working voltage is 3V, and the current is only 50mA during operation. In the design, the DC motor is used to drive the forward or reverse rotation of the hemispherical valve to control the opening and closing of the valve, and whether the switch state of the motor is in place is judged by the in-position switch signal.

Communication module 9: Various wired/wireless remote communication modes are optional, realizing remote reading of user data. The wireless communication adopts NB-IOT or LoRa for regular reporting, and the communication module 9 is usually turned off to reduce power consumption. The wired communication method can use MBUS mode, and the communication is powered by M-BUS or 485 bus, which reduces the power consumption of the product itself.

Photoelectric switch 10: The photoelectric switch 10 is combined with the structural design. When the upper cover of the water meter is buckled, no external light enters. When the upper cover is opened, the light illuminates the optical switch. The output signal of the optical switch triggers the interrupt of the microcontroller 1, which is controlled by the microcontroller 1. The LCD display turns pages, and the user mode and verification mode can also be switched according to the duration of the optical switch signal.

Infrared communication module 11 : an infrared transmitting tube and an infrared receiving tube are used, both of which are connected to the IO port of the microcontroller 1 . The specific principle of infrared communication can be the content of the existing technology. For details, please refer to the introduction of infrared communication and DS18B20 temperature sensor in "Single-chip Microcomputer Learning Course".

The ultrasonic water meter of the present invention adopts a battery-powered mode, and the battery can hold a limited amount of power. In order to prolong the service cycle of the battery, a low-power microcontroller 1 and a low-power design of software and hardware must be used. Therefore, it can meet the needs of this low-power system.

After the installation of the water meter, use the calibration software to calibrate the water meter, and write the calibration result into the water meter to ensure the accuracy of the water meter. The software flow chart of the ultrasonic water meter measurement part is shown in Figure 7.

Symbols in the flow chart of software implementation of measurement module 3:

TOF: time difference

X: zero offset value

When I:i>=19, it means that the water flows. When i<19, it means that the water flow was still before.

w_speed: flow velocity

TOF_ave: Average of the first 9 numbers in TOF_10[10]

TOF_10[10]: 10 numbers in the array. The data stored in the benchmark V1, TOF_10 [10] for the first time is updated after each TOF data is collected.

The present invention has the following advantages:

1) Low power consumption: select a low-power chip suitable for the present invention, turn off the peripheral circuits that consume a lot of power when not in use, set the unused IO ports reasonably, and set the system clock to the internal clock to reduce power consumption , before the system enters low power consumption, the peripheral clocks that are not used will be turned off to reduce power consumption and low power consumption, and the current is less than 30uA.

2) Wide range ratio: STM32-bit microcontroller 1 is used as the core control device of the present invention, which can more accurately measure the propagation time difference of ultrasonic beams in water. Through many experiments, the most suitable configuration mode of GP22 chip is determined to ensure the accuracy of the measured ultrasonic beam propagation time difference in water; a large amount of data is obtained to obtain the law, and the measurement algorithm is realized; due to the propagation speed of ultrasonic waves in water with different temperatures Different, it is necessary to select an accurate functional relationship through testing to ensure that the speed of ultrasonic waves at different water temperatures is calculated correctly.

3) A variety of data communication methods are available: M-BUS or 485 bus communication can be selected for wired remote transmission, which can realize one-to-many transmission mode, greatly reducing the cost of manual meter reading and improving the meter reading rate. The wireless remote transmission can choose NB-IOT or LoRa, and report the data to the microcontroller 1 regularly.

Contents that are not described in detail in the present invention are all in the prior art.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (5)

1. A novel ultrasonic intelligent water meter is characterized by comprising a microcontroller (1), wherein the microcontroller (1) is respectively connected with a power supply module (2), a measuring module (3), a liquid crystal display module (4), a voltage detection module (5), a temperature detection module (6), a storage module (7), a valve control module (8), a communication module (9), a photoelectric switch (10) and an infrared communication module (11) and controls the same; the photoelectric switch (10) transmits a switching signal to the microcontroller (1) through light change irradiated on the water meter cover, the microcontroller (1) is triggered to perform switching operation, the microcontroller (1) controls the liquid crystal display module (4) to turn pages, and the microcontroller (1) is internally provided with an EEPROM unit.

2. The novel ultrasonic intelligent water meter according to claim 1, wherein the power module (2), the voltage detection module (5), the temperature detection module (6) and the photoelectric switch (10) are connected with an input end of the microcontroller (1), the liquid crystal display module (4) is connected with an output end of the microcontroller (1), and the measurement module (3), the storage module (7), the valve control module (8), the communication module (9) and the infrared communication module (11) are all in bidirectional connection with the microcontroller (1).

3. A novel ultrasonic intelligent water meter as claimed in claim 1, characterized in that said microcontroller (1) employs STM32, which is an ultra low power, high performance ARM Cortex-M3 chip, low power mode current less than 30 μ Α, and operating voltage of 1.8-3.6V.

4. A novel ultrasonic intelligent water meter as claimed in claim 1, wherein the communication module (9) includes wired communication and wireless communication, and the wired communication adopts M-BUS or 485 BUS communication; the wireless communication adopts NB-IOT or LoRa to report the timing data of the microcontroller (1).

5. A novel intelligent ultrasonic water meter as claimed in any one of claims 1 to 4, wherein said power module (2) employs a 3.6V lithium battery; the measuring module (3) consists of a TDC _ GP22 chip, an ultrasonic probe, an emission control circuit and an ultrasonic signal processing circuit; the liquid crystal display module (4) comprises a liquid crystal driver and a liquid crystal screen, and a man-machine interaction interface is formed; the voltage detection module (5) collects voltage signals through an AD conversion interface of the microcontroller (1); the temperature detection module (6) adopts a DS18B20 temperature sensor and is used for collecting the real-time temperature of water flow of the water meter; the storage module (7) adopts a memory internally provided with a high-capacity Flash chip; the valve control module (8) adopts an electric ball valve, and the opening and closing of the valve are controlled by driving the electric ball valve to rotate forwards or reversely through a direct current motor; the infrared communication module (11) adopts an infrared transmitting tube and an infrared receiving tube which are connected to an IO port of the microcontroller (1).

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