CN102872641A - ARM-based self-cleaning filter controller - Google Patents

Abstract

Belong to the field of automation control, the invention relates to an ARM-based self-cleaning filter controller. The hardware of the controller includes: a main chip, a differential pressure sensor, an alarm and control module, a touch screen display module, and a communication module. The control program of the controller is composed of a main program and function module subprograms.

Description

A kind of self-cleaning filter controller based on ARM

Technical field

The invention belongs to automation control area.

Background technology

Along with the growing tension of water resource, slight irrigation is used widely as one of advanced irrigation technique of a kind of the most agricultural water conservation, also is one of development trend of from now on agricultural water conservation.But the current aperture of the equipment such as drip irrigation zone, mini sprinkler is generally all very little in the irrigation system in actual application, is very easily stopped up by the various dirts in the water.And in fact any water source such as rivers and canals water, rainwater, Ku Tangshui contain various dirts and impurity to some extent, therefore reasonably choose filter and iirigation water source are carried out silt is processed and other purified treatment are requisite steps in the slight irrigation.The great majority that domestic irrigation system uses now are gravel filter and centrifugal type filter, and automaticity is low, and the performance less stable is difficult to satisfy the demand that develops.Therefore, need to research and develop the full-automatic back washing water filter, to improve the overall technology level of Industrial Agriculture in Our Country equipment.

This paper is after carrying out research and comparison to domestic and international filter, the comprehensive at present pluses and minuses of filter controller and the development trend of controller, a kind of design of differential pressure adjustable automatic backwashing filter of multi-drop is proposed, overcome the deficiency of present domestic backwash filter, filter has continuous filtration, automatic backwash blowdown advantage.The automaticity of system is high.Powerful, expansion can be set.Satisfy different user's requests.

Summary of the invention

The present invention is exactly for the problems referred to above, and a kind of self-cleaning filter controller based on ARM is provided.

For above-mentioned purpose, the present invention is achieved in that

Hardware of the present invention comprises master chip, and differential pressure pickup is reported to the police and control module touch-screen display module, communication module; Control program is comprised of main program and each functional module subprogram.

Beneficial effect of the present invention:

The invention provides a kind of mentality of designing of new filter controller, control system has adopted the development board based on embedded platform ARM, controller system can come according to pressure reduction, flow and the clock own etc. that sensor obtains the situation of analysis-by-synthesis filter, thereby take appropriate measures to guarantee the normal operation of filter, realized the real-time control of filter, full automatic working, system has intelligent, extraordinary case diagnose and warning function.

The user can use the touch-screen parameters, and is flexible and convenient to use.

System can conveniently expand with the serial ports of standard.Controller has the output of No. 12 relays, 8 road analog inputs and the input of 8 way switch amounts, can support multiple backwash Starting mode by embedded software developing, can control with the filtration backwash by environment information acquisition, also can be used as a downstream plant, form centralized filtration control system by large-scale industrial computer, it also supports note operated from a distance control simultaneously.

Description of drawings

Fig. 1 is the hardware connecting circuit block diagram of controller.

The specific embodiment

The serial LPC2368 of the ARM7 that this system selects philips company to produce is as the master chip of system.The LPC2368 chip has a plurality of IO ports, inside is integrated with AD converter, serial communication interface, Ethernet interface etc., LPC2368 is the processor of a TDMI-S, and supports the CPU of real-time simulation and tracking, can work under the operating frequency up to 72MHZ, up to the in-chip FLASH program storage of 512KB, have at System build with in the application compiling.System carries 60 WatchDog Timers.Low in energy consumption in addition in addition, support that nearly 32 vectors interrupt, various serial ports, various APB peripheral hardwares etc., functional interface is abundant, is particularly suitable for the exploitation of the systems such as Industry Control.

When sewage enters filter by water inlet pipe, impurities accumulation innerly can produce difference pressuring loss at the inner surface of filter screen in filter process; When reaching certain pressure reduction, filter screen can stop up.Therefore we find out the critical value of pressure reduction by the test of many times analysis, and critical value is stored in the memory as the benchmark that cleans, and a plurality of a reference values or a value range can be set, the supply user selection.The pressure reduction Starting mode is one of cleaning Starting mode of filter, in the native system, the differential pressure pickup that adopts is the MPX5700 series piezoresistive transducer of Freescale, MPX5700 is state-of-the art single piece of silicon pressure sensor, various application be can be widely used in, microcontroller or microprocessor application with the A/D input particularly adopted.Just be fit to the use of native system.This patented single-element sensor integrates advanced micromachining technology, thin film metallized and bipolar technology, can provide and is directly proportional by measuring pressure.Accurate high level analogue output signal.Worst error is 2.5% in 0 to 85 ℃ of scope, and output valve is the pressure sensor of 0.2-5.0v.Measurement category is 0-500kpa, two of differential pressure pickup is terminated to water inlet and the delivery outlet of filter, LPC2368 calculates dress to the voltage of measuring gained and changes the pressure difference that just can obtain correspondence, compares with intrasystem a reference value, thereby makes the decision that whether will clean.

The cleaning of filter mainly is to realize by the control magnetic valve, because what magnetic valve adopted is to exchange 24v, operating voltage than LPC2368 is high a lot, so adopted the relay isolated controlling, when controller receives pressure reduction or time when reaching the threshold value of cleaning, send order and open magnetic valve, carry out backwash.In addition, when system's abnormal as cleaning iterative cycles, magnetic valve can not start, filtration can't be carried out etc., controller control buzzer call is reported to the police, with call user's attention.Adopt corresponding measure to solve.

The very color display screen of 7 inches TFT of high brightness that native system is equipped with, touch function make control and the parameter monitoring of filtration and backwash become simple and clear.What liquid crystal display was selected is the intelligent terminal display module of Beijing Dwin Technology Co., Ltd., graphic dot matrix is 800x480., intelligent display terminal has integrated standard character library, selectable operator scheme, both can also can input with touch-screen with the keyboard input, and be based on the graphical interfaces operation.As long as MCU has serial ports, just can be connected with display terminal, connected mode is simple, and terminal both can be used TTL, also can with the work of COMS level, also can work with the RS232 level, and support the USB download pictures.The four-wire ohm touch-screen.Touch screen interaction, interface become the form of picture, and be directly perceived, easy to operate.In native system, controller is connected with serial ports with liquid crystal, and wiring is simple and convenient, and what this liquid crystal adopted in addition is the 3.3v Power supply, and voltage backlight is 4.2v.

Controller has adopted the RS485 bus standard with communicating by letter of host computer, has consisted of half duplex communication by the serial ports of MAX485 chip and LPC2368, and MAX485 is 3.3V low-power consumption Half-duplex transceiver.Message transmission rate is up to 10MBPS, by LPC2368 control transmitting-receiving Enable Pin, system adopts the UART module pin TXD0 of LPC2368, RXD0 respectively with the DI of MAX485, RO connects, in addition, because the interface of host computer is the RS232 of standard, so need the RS232/RS485 converter that signal is changed during communication.The native system equipment room communicates by the Modbus agreement, and the Modbus100 agreement is a kind of industrial communication agreement of standard, compares with other agreements, and hardware cost is low, and agreement realizes simple.

Consider the relatively dispersion because the filter website distributes, wiring cost is high, the factors such as site environment is abominable, adopt wireless system to collect with the transmission of data proper, what native system adopted is the form that GSM sends note, controller is connected with mobile module TC35i by UART, finishes read-write and the control of TC35i module.TC35i supports BLOCK, TEXT, three kinds of coded systems of PDU105.Native system has adopted present most widely used PDU coded system, and this mode has adopted 16 scale codings, can transmit English, numeral, and Chinese, system adopts and sends AT order control TC35i work, and the main AT order of using arranges messaging format: AT+CMGF; Send note length: AT+CMGS; List short message AT+CMGL, reading short message breath AT+CMGR, deleting short message breath AT+CMGD etc.

The working procedure of filter mainly is to adopt the c language compilation, and UCOS2 operating system is adopted in modularized design.Whole program is comprised of main program and each functional module subprogram.Wherein the program of slave computer is to write according to cleaning function and the flow process of automatic cleaning controller, mainly is detection hardware, and acquisition process interrupt to be processed, the parameter setting, control output etc., flow chart as shown in Figure 3,

Filter control system mainly is that 16 websites of 4 filtration groups are carried out control operation, and each filter set comprises Real Time Monitoring, parameter setting, historical query etc.Software needs the user to confirm that just can enter parameter after the identity arranges picture.Control system provides 4 kinds of Starting mode for each user's request.Greatly satisfied user's request.Comprise: manually boot, pressure reduction starts, and the water yield starts, and the time starts.In parameter arranged, the parameters that the user can system arranged.Finish the setting to communications protocol, Time of Day and I/O channel.Such as arranging startup pressure reduction, the pressure reduction of 5 startups can be set at most, the time startup arranges filtration time, scavenging period, system start-up time, starting duration, intermittently duration etc., the setting of communications protocol is that the user is to uploading channel, scan channel, Long-distance Control etc. arrange, after the parameter setting is finished, system will operate after clicking start button, the LCD liquid crystal display can clearly show the state of present filter, the state of differential pressure pickup, the state of long-range water meter, the running status of each website, state of communication etc.

This control system can be widely used in centralized filtration control, infiltrate without terminal filtration control, note operated from a distance filtration control and automatic cycle and filter in the filtration Control Engineering of the various ways such as control.According to system requirements, controller needs the duty of Real-Time Monitoring filter, and when having served as filtering medium decline, the duty of automatic switchover filter element is finished the self-cleaning of filter element; System can the online modification parameter, can select several filter elements to form filtration system according to actual conditions, and can revise each operational factor; System can move the realization filter process, controller backwash process, wash number, the station number of filtration, Starting mode, the real-time demonstration of automatic alarm; System can realize self check, communication, the functions such as warning.

Claims (6)

1. self-cleaning filter controller based on ARM, hardware comprises master chip, differential pressure pickup is reported to the police and control module touch-screen display module, communication module; Control program is comprised of main program and each functional module subprogram.

2. a kind of self-cleaning filter controller based on ARM according to claim 1 uses ARM7 series LPC2368 as the master chip of system.

3. a kind of self-cleaning filter controller based on ARM according to claim 1 adopts the MPX5700 series piezoresistive transducer of Freescale as differential pressure pickup.

4. a kind of self-cleaning filter controller based on ARM according to claim 1 adopts the very color display screen of 7 inches TFT of high brightness as touch-screen display.

5. a kind of self-cleaning filter controller based on ARM according to claim 1 has adopted the RS485 bus standard, and has been provided with the RS232/RS485 converter.

6. a kind of self-cleaning filter controller based on ARM according to claim 1, controller is connected with mobile module TC35i by UART.

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