CN203174694U - Constant-pressure variable frequency water supply control device based on ARM - Google Patents

Abstract

The utility model discloses an ARM-based constant pressure frequency conversion water supply control device. The water pressure signal acquisition and processing module uses the water supply pipe network pressure transmitter to convert the water pressure information into a 0~5vDC signal, which is adjusted by a preprocessing circuit. The voltage signal of 0~+3.3v realizes the digital processing of the water pressure signal through the analog-to-digital conversion module of the ARM9 main controller; uses the embedded expert fuzzy PID controller to complete the comparison between the set value of the pipe network pressure and the actual pressure, intelligent PID Operational control, finally convert the new operating parameters of the control system into analog signals to control the output frequency of the inverter, and then control the speed of the pump motor, and finally achieve a new balance between the water supply flow and water flow, and realize the variable speed operation of the water pump unit Control and adjust the water pressure of the water supply network in real time, so as to achieve the purpose of energy saving control. The utility model is easy to maintain, and because the system is simple, the maintenance is greatly facilitated and the maintenance cost is reduced.

Description

Constant pressure variable frequency water supply control device based on ARM

technical field

The utility model relates to a water supply and drainage device, in particular to an ARM-based constant pressure variable frequency water supply control device.

Background technique

With the continuous development of the economy, more and more people live in cities, and the burden on the water supply system is gradually increasing. How to effectively solve the problem of water supply for residents is one of the key factors related to the quality of life of residents. For a long time, technologies such as residential water supply, industrial production circulating water supply, municipal water supply, and fire-fighting water supply have been relatively backward, and the contradiction between water supply and demand has become more prominent. Due to insufficient water supply, the economic loss of urban industry is as high as hundreds of billions of yuan, and the quality of life of urban residents has seriously declined, which has become a major problem in the process of urbanization in my country.

The contradiction between water supply and demand is mainly manifested in insufficient water supply or excess water supply. That is, during the peak period of water consumption, there is a phenomenon that the water pressure decreases and the supply exceeds the demand. For example, it is difficult for high-rise users to use water during the peak period of water consumption in residential areas. In the low peak period of water use, there will be an oversupply phenomenon, resulting in a waste of water resources. The contradiction between water supply requirements is mainly caused by two reasons. On the one hand, the traditional water supply mainly uses water supply from water towers or high-level water tanks, water supply from pressure tanks, and water supply from pump components. Its main disadvantages are large floor space, high investment, frequent start-up of the pump motor, difficult maintenance and overhaul, etc., which are far from meeting the high-pressure water supply requirements of high-rise buildings and industries. On the other hand, due to the randomness of users' water consumption, it is difficult to guarantee the real-time performance of water supply, and the traditional water supply method is mainly a constant speed control system. Water supply companies usually make the water pump work at full load. During the low peak period, not only the working efficiency of the water pump is reduced, the water supply pressure is unstable, but also the waste of electric energy is caused. According to statistics, the power consumption of water pump motors accounts for more than 20% of the country's total power consumption.

Therefore, in order to solve the above problems, research on the constant pressure variable frequency water supply control system with intelligent processing capabilities can not only keep the water supply pressure constant, that is, maintain a balance between the user's water consumption and the water supply volume, so that the water supply pressure can be stabilized within a specific range , and can save water supply energy consumption to a certain extent, is the main research motivation of this patent.

In recent years, the continuous development and maturity of power electronics and computer technology, AC frequency conversion speed regulation technology, intelligent control and remote communication technology have also laid a theoretical foundation for the research of this patent. At the same time, the technology based on ARM embedded system is also Continuous advancement, it is easy to learn, easy to use, simple in structure, complete in function, simplifies system design, reduces system scale, shortens design cycle, reduces production design cost, and it also has fast computing speed, low power consumption, network communication The advantage of convenience, which also provides technical support for the hardware design of the intelligent constant pressure variable frequency water supply control system.

Utility model content

The purpose of the utility model is to provide an ARM-based constant-voltage variable-frequency water supply control device in order to make up for the defects of the prior art.

The utility model is achieved through the following technical solutions:

A constant pressure variable frequency water supply control device based on ARM, including ARM9 main controller with fuzzy-PID control algorithm, DA converter, pressure transmitter, frequency converter, contactor group, water pump unit, water supply pipe network and RJ-45 Ethernet interface, the output ends of the frequency converter are respectively connected to a plurality of contactors of the contactor group, and the plurality of contactors of the contactor group are respectively connected to a plurality of water pumps of the water pump unit machine, the water pump unit is connected to the inlet of the water supply pipe network, the outlet of the water supply pipe network is provided with a pressure transmitter, and the positive and negative pins of the pressure transmitter are respectively connected to the ARM9 Channel 2 and channel 3 in the ADC conversion channel of the main controller, the output port of the ARM9 main controller is connected to the input port of the DA converter, and the output port of the DA converter is connected to the input of the frequency converter At the end, the RTL8019 network interface plug-in of the ARM9 main controller is connected to the RJ-45 Ethernet interface.

The model of the ARM9 main controller is ARM9S3C2440, the model of the pressure transmitter is SMP131, the model of the frequency converter is MM430, and the model of the DA converter is AD5552.

、DIN和SCLK连接。 The connection between the ARM9 main controller and the DA converter is that the pins GPB.2, GPB.3, GPB.4 and TXD of the ARM9 main controller are respectively connected with the pins of the DA converter ,

, DIN, and SCLK connections.

The ADC conversion channels in the ARM9 main controller are eight 10-bit conversion channels.

The working principle of the utility model is: the water pressure acquisition and processing module of the water supply pipe network is connected by the ARM9 main controller through the external pressure transmitter, the current and voltage isolation transmission unit and the built-in ADC conversion channel of the ARM9 main controller to realize The water pressure information is collected regularly and the average value of each time period is calculated to reduce the real-time water pressure error.

The ARM9 main controller first reads the real-time pressure value from the conversion register of the ADC conversion channel, obtains the given value of the frequency conversion control frequency parameter according to the intelligent expert PID control algorithm, and then uses the DAC conversion module to filter and transmit it to the frequency converter to realize Motor frequency conversion speed control.

The pressure and frequency conversion control parameters are packaged and uploaded to the remote monitoring host through the RJ-45 Ethernet interface through the network interface RTL8019 inside the ARM9, and the intelligent remote monitoring system design is realized on the monitoring host side.

The utility model has the advantages of:

1. The utility model uses S3C2440 as the core of the ARM9 embedded system to construct constant voltage variable frequency control real-time acquisition processing and expert intelligent variable frequency control device, which replaces the traditional PLC control device and improves the operation speed and precision of the control system. The strong storage capacity of the system realizes the effective transplantation of the expert-fuzzy PID algorithm, and the use of the embedded system's multi-process and other efficient computing and processing capabilities reduces the time-consuming problem of complex control algorithms, improves the real-time processing capabilities of the system, and significantly improves performance. On the other hand, because the network interface card that comes with the embedded system can effectively and conveniently connect the control system to the Internet, the remote communication function of the pressure frequency conversion control system is significantly enhanced, and the efficiency of the water supply control link is effectively improved. Remote intelligent monitoring, you can browse and check the status of constant voltage and frequency conversion control from the host computer at any time.

2. The utility model transplants the expert fuzzy adaptive PID control algorithm into the embedded system, so that the pressure control device has strong adaptability, fast response speed, simple control system, and the simple setting of the system control part further brings high reliability of the system.

3. The system of this utility model adopts unitized setting, which makes the system connection intuitive and simple, and the installation, debugging and maintenance of the system become extremely simple. Through programming control, water pressure monitoring and drawing of water pressure history curves can be realized.

4. The utility model is easy to maintain, and because the system is simple, it greatly facilitates maintenance and reduces maintenance costs.

Description of drawings

Fig. 1 is a block diagram of the utility model system.

Fig. 2 is the main control unit of the network intelligent control system of the present invention.

Fig. 3 is the D/A conversion frequency conversion output control driving unit of the utility model.

Fig. 4 is the driving unit of the network communication interface circuit of the utility model.

Detailed ways

As shown in Figures 1, 2, 3, and 4, an ARM-based constant-pressure variable-frequency water supply control device includes an ARM9 main controller 1 with a fuzzy-PID control algorithm, a DA converter 2, and a pressure transmitter 4 , frequency converter 3, contactor group 5, water pump unit 6, water supply pipe network 7 and RJ-45 Ethernet interface 8, the output ends of the frequency converter 3 are respectively connected to multiple contactors of the contactor group 5 A plurality of contactors of the contactor group 5 are respectively connected to multiple water pumps of the water pump unit 6, and the water pump unit 6 is connected to the inlet of the water supply pipe network 7, and the water supply pipe network The outlet of 7 is provided with a pressure transmitter 4, and the positive and negative pins of the pressure transmitter 4 are respectively connected to channel 2 and channel 3 in the ADC conversion channel of the ARM9 master controller 1, and the ARM9 master The output port of the controller 1 is connected to the input port of the DA converter 2, the output port of the DA converter 2 is connected to the input end of the frequency converter 3, and the network interface plug-in of the RTL8019 of the ARM9 main controller 1 Connect the RJ-45 Ethernet port 8 as described.

The model of the ARM9 main controller 1 is ARM9S3C2440, the model of the pressure transmitter 4 is SMP131, the model of the frequency converter 3 is MM430, and the model of the DA converter 2 is AD5552.

、

、DIN和SCLK连接。 The connection between the ARM9 main controller 1 and the DA converter 2 is that the pins GPB.2, GPB.3, GPB.4 and TXD of the ARM9 main controller 1 are respectively connected with the pins of the DA converter 2

,

, DIN, and SCLK connections.

The ADC conversion channels in the ARM9 main controller 1 are eight 10-bit conversion channels.

Shown in Fig. 1 is that the utility model system forms a block diagram. The amount of water demanded by users of the water supply system determines the actual water pressure that the pipe network should achieve. As can be seen from Figure 1, the entire control system is connected by the pressure transmitter 4 to the water supply pipe network 7, the water pump unit 6 and the main control part. The signal is converted into an electrical signal, connected to the ADC conversion module inside the ARM9 main controller 1 through the pressure transmitter to convert it into a digital signal, and then after calculation and processing, it is compared with the pressure value set by the water supply system to obtain the pressure signal The deviation value, and then get the new frequency conversion control parameters of the control system through the embedded expert fuzzy-PID adaptive controller, convert it into an analog signal to control the output frequency of the frequency converter, and then control the speed of the water pump motor, and finally make the water supply flow and water consumption The flow reaches a new balance, and the pipe network pressure remains constant at the set value. Among them, the constant pressure water supply system uses SMP131 general-purpose pressure transmitter 4 for the detection, display and transmission of pressure, and finally converts the water pressure signal into a voltage signal of 0~+3.3v and connects it to the embedded system ADC for conversion Channels AIN1 and AIN2 are converted into voltage digital quantities; the frequency conversion control of the water pump uses the intelligent expert fuzzy PID control module transplanted in the embedded system to compare the real-time pressure value with the set value, intelligent expert fuzzy PID calculation, and frequency conversion control The output is completed in three steps. The calculation result of the intelligent expert fuzzy PID control is a digital quantity, which needs to be connected with the external DA converter AD5552 through the serial interface, and continuously use the digital output to adjust the frequency output parameters of the inverter MM430; when adjusting the water pump unit When the rotation speed is high, one frequency conversion is used, and the rest work in the power frequency mode, which effectively improves the control efficiency and energy saving effect; the monitoring module uses socket technology and TCP/IP protocol to realize the communication with the host computer through the RJ45 interface of the Ethernet network. Connection and remote communication, complete the remote monitoring of parameters such as pipe network water pressure, inverter frequency parameters, and pump unit working status, and finally complete the design of the embedded constant pressure variable frequency control device.

Figure 2 shows the main control unit of the utility model, that is, the embedded minimum control system, which mainly includes a power supply system module, which can provide a power supply signal of 1.8 to 5V for the kernel, Ethernet communication, JTAG debugging, and A/D conversion; The crystal oscillator circuit provides various clock signals for the system; the system reset circuit uses a special microprocessor power monitoring chip SP708S, which can effectively improve the reliability of the system and prevent the CPU from sending wrong instructions; the internal ADC interface can regularly collect pipe network pressure data, and use The internal register ADDR stores the conversion result for query; the control parameter and the external DAC interface chip realize the serial transmission of the control parameter to the DAC through serial mode; remote communication.

相连，利用GPB.3与AD5552的相连，利用串行接口GPA.4与DIN相连，实现串行数据的输入，利用TXD实现AD5552的时钟驱动信号接入，与AD5552的SCLK相连，数据在SCLK的上升沿被时钟信号引入DAC寄存器，并实现D/A转换。转换的输出通过Vout端与MM430变频器直接相连，完成变频控制参数的模拟传递。 Figure 3 shows the frequency conversion digital-analog drive circuit of the utility model, the main function is to realize the control output of the embedded system to the frequency converter through digital-to-analog conversion, and then complete the variable-speed operation of the asynchronous motor, thereby effectively adjusting the flow of the pipeline and realizing the control of the pipeline. Network constant pressure frequency conversion control and energy-saving control of water pump unit. ARM9 S3C2440 through GPA.2 and AD5552 analog-to-digital converter

connected, using GPB.3 and AD5552’s Connected, use the serial interface GPA.4 to connect with DIN to realize the input of serial data, use TXD to realize the clock drive signal access of AD5552, connect with SCLK of AD5552, the data is introduced into the DAC register by the clock signal at the rising edge of SCLK, And realize D/A conversion. The converted output is directly connected to the MM430 frequency converter through the Vout terminal to complete the analog transmission of the frequency conversion control parameters.

Figure 4 shows the network communication interface circuit of the utility model, the main function is to use the RTL8019 network card and RJ45 network interface to quickly connect the embedded constant voltage frequency conversion control system to the enterprise internal Ethernet and connect it to the upper monitoring host. The hardware connection between S3C2440 and RTL8019AS is shown in Figure 4. IOCS16B is a 16-bit I/O selection pin. When the network card is powered on and reset, if the input of this pin is low, the network card works in 8-bit mode; if The input of this pin is high level, and the network card works in 16-bit mode. In this design, 16-bit mode is used to read and write the RTL8019AS chip, and the IOCS16B pin on the RTL8019AS is pulled up through a 10K resistor, and the RTL8019AS chip is read and written in IO mode. SMEMRB and SMEMWB are connected with pull-up resistors to VCC. Apply a high level RTL8019AS reset on the RSTDRV pin for more than 800ns. Address lines A0-A4 are connected to SA0-SA4, SA8-SA9 is pulled up and connected to Vcc, SA5-SA7, SA10-SA19 are grounded. Finally, the design of the Ethernet monitoring network access module is completed.

Claims (4)

1. constant pressure frequency conversion water supply control apparatus based on ARM, it is characterized in that: include the ARM9 master controller that has the fuzzy-PID control algorithm, the DA converter, pressure transmitter, frequency converter, the contactor group, water pump assembly, water supply network and RJ-45 Ethernet interface, the output of described frequency converter connects a plurality of contactors of described contactor group respectively, a plurality of contactors of described contactor group connect a plurality of water pump machines of described water pump assembly respectively, described water pump assembly is connected with the entrance of described water supply network, the exit of described water supply network is provided with pressure transmitter, the positive and negative terminal pin of pressure transmitter connects passage 2 and the passage 3 in the ADC ALT-CH alternate channel of described ARM9 master controller respectively, the output port of described ARM9 master controller connects the input port of described DA converter, the output port of DA converter connects the input of described frequency converter, and the network interface card of the RTL8019 of described ARM9 master controller connects described RJ-45 Ethernet interface.

2. the constant pressure frequency conversion water supply control apparatus based on ARM according to claim 1, it is characterized in that: the model of described ARM9 master controller is ARM9S3C2440, the model of described pressure transmitter is SMP131, the model of described frequency converter is MM430, and the model of described DA converter is AD5552.

3. the constant pressure frequency conversion water supply control apparatus based on ARM according to claim 1 is characterized in that: pin GPB.2, the GPB.3, GPB.4 and the TXD that are connected to the ARM9 master controller between described ARM9 master controller and the DA converter respectively with the pin of DA converter

,

, DIN is connected with SCLK.

4. the constant pressure frequency conversion water supply control apparatus based on ARM according to claim 1, it is characterized in that: the ADC ALT-CH alternate channel in the described ARM9 master controller is 8 tunnel 10 ALT-CH alternate channels.

Images