| This paper is subject to national emphasized groundword research item about the disposal of the city waste using incineration, and it focuses on the research of the monitoring system and controlling system of the multilayer Circulation Fluidized Bed boiler which is used in Wuhu Power Plant and Hangzhou Qiaosi Power Plant of waste-incinerated, while considering an utilizing advanced technology and experience domestically and abroad. The key points of this paper include the design of software and hardware of the system, the realization of automatic control function , and upgrade of system software.The monitoring and controlling system adopts a total distributed control system(DCS) constituted by a programmable logic controller(PLC)N a computer(PC) and thermal power engineering signal sensors sender controller, etc. PLC is used to collect data and perform automatic control mostly, while PC is adopted to monitor the thermal engineering parameters, analyze, display and store data.This paper contents software development of PLC and PC. The software for PC developed by Visual C++ proves to be effective and friendly to operators, which can realize many functions such as process display, list-display of boiler parameters, alarming, history data querying, automatic creation of worksheet, and trend monitor, etc. We also upbuild intranet between the different DCS systems and computers to transfer the real time data and communicate. The software for PLC programmed by SETP 7, which can successfully detects signals and controls the loops.This paper has also carried out product alteration on thermal engineering monitoring and controlling software developed by ourselves, including newly constructing software, improving software capability, strengthening configuration software , controlling software edition and enhancing software quality, etc. The upper machine' software in Wuhu plant is analyzed and designed with object-oriented method. On developing new system the software is constructed renewedly, and especially the data management is renewed through improving the class of CDataManage, so much stronger and more flexible functions of data services are offered. Introducing the technology of multithreading has enhanced the using of CPU; Using the technology of double buffers has eliminated dithering of the curve of program display; Developing relative GUI for the new class of CDataManage has improved the level of software configuration. In order to improve the competition power of the monitoring and controlling system, I try to perfect logic and graph function of the software, for instance, I develop more practical report-form system,more elegant interface-display, and more complete alarm system.The design of an automatic control system for the Hangzhou Qiaosi Power Plant is also included in this paper. The system uses PID controller and fuzzy controller to design automatic control loops, a study of fuzzy three-element feed-water control system for a CFB municipal waste incinerator is introduced. The incinerator is faced with problems such as large-scale fluctuation of furnace heat load and low regulation resolution of main control feed-water valve. The fuzzy logic control system is applied to modulate PI control parameters according to steam drum water level to fit fluctuated heat load, the inner and outer control loops are realized in an asynchronous way to effectively decrease regulation time and improve regulation precision. |
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