The Research Of Modular Self-Cleaning Filter Controller

Water is the most important resource to human. Men can not survive without water. By reusing the treated sewage, men can not only reduce the harm caused by the effluent to the environment, but also find an important way to solve the shortage of water resource. Filtering is a basic and important process in water treatment. To solve the defects of filters at present, this paper studies the theory of self-cleaning filtration system consisted of small self-cleaning filtration modules, and develops a controller based on microprocessor.This paper studies the mechanism of filtration, analyses the reasons for the decline in the quality of a filter. According to Darcy theorem, this paper introduces a solution which controls the filter's self-cleaning operation by monitoring the pressure difference between in and out water. Based on this theory, the paper introduces the technique of manufacture filtration system by using self-cleaning filtration modules, analyses the two different work status of individual filtration modules, studies the theory of shifting the work status of filtration modules to implement the continual clean water supply and self-cleaning on line.In order to enlarge filtration capacity, real-time supply water, reduce the manufacturing difficulties and cost, this paper analyses the control theory of self-cleaning module filter. In terms of function, the system is divided into four modules: status monitor module, control & performance module, communication module, and configuration module. This paper analyses the feasibility of the project and makes a final choice.This paper introduces the overall performance and main characters of MSP430F123, designs hardware circuits of various modules. For lack of IO ports of MCU, this paper studies the serial and parallel IO ports expending methods, and provides a solution which using MAX7301 to expand IO ports based on SPI protocols. This paper uses SSR as power interface, introduces the operating principles and main features of SSR, and designs the application circuit.This paper analyses the software's function and compartmentalizes it to modules, completes the development and debug work with the integrated development tools: Embedded Workbench.Under the cooperation with DALIAN AUTO-FILTER EQUIPMENT LTD., we have finished the manufacture of filtration system. With practical operation and test, the system has been proved reliable and robust;the design is correct and attains its expectd goals.