The Design Of Regional Alarm And Control Units For Electric Fire Prevention Based On STM32

Along with substantial growth of electricity consumption in production and life in China, the rate of electric fire incidence is rising, and electric fire is becoming a serious disaster which is a danger to life and property safety. How to effectively monitor the electrical fire, and early detect its hazards to prevent it is a serious problem to be solved in electric fires prevention field.At present, most of alarm and control system for electric fire prevention has limited data processing capacity, inefficient communication, leading to it has many inconveniences in building system. This is mainly because that alarm and control unit for electric fire prevention which is in the middle layer of the system is not equipped to handle large quantity of data and multi-way communication. This paper designs an improved unit, which uses the STM32 microprocessor based on ARM-core, and supports four communication methods, such as GPRS, RS-485 bus, Two-wire bus and Ethernet, with a friendly interactive interface to compensate for the shortcomings of similar products, and improve performance of the system.First, this paper gives a detailed description in the principle of three electric fire detection technologies, which are leakage current detection method, wire temperature detection method and infrared temperature measurement method, they are the basis of the system. Then, refer to national standards about the system design, this paper describes the hierarchical distributed structure and its work procedures of the system, and points out that the limited performance of regional alarm and control unit for electric fire prevention is the bottleneck of the system. Then, it proposes an improved unit, and gives the functional requirements and implementation of the unit.Program is implemented in two parts:hardware design and software design. According to the architecture of alarm and control unit for electric fire prevention, we design the hardware modules, and explain how they work, and compare the performance of them with other programs. Then, we chooseμC/OS-Ⅱas our software development platform, which is an embedded Real-time operating system, and has many advantages in embedded development. On this platform, the software is divided into several modules, and this paper highlight the idea of program design and several key technologies for four methods to communicate and LCD display. Finally, this paper describes the signal processing algorithms for electrical fire which is commonly used, and presents the simulation and analysis of the alaorithms.