Design And Implementation Of Remote Monitoring Control System For Electric Parameters Based On GPRS

Aim at meeting the requirements of electric system management automation and cyberlization , this thesis describes a system which builds up a wireless, real-time electric parameters supervisory control system depending on GPRS network of China Mobile Telecommunication Company. First, we understand the design tasks and functions of the system to be implemented by analyzing the customs'requirements. The system is divided into three parts: data acquisition of electric parameters, data communication via wireless network and real-time monitoring & managing information system. Among them, the first two parts are needed to be implemented in the GPRS network application system; The third part management system is run on the server of electric department. These are a lots of electric parameters to be measured, and the measurement process is time-consumption, their computations are complicated. In order to simplify the system hardware design, save CPU bandwidth, reduce the cost, a special power measurement IC CS5460A is taken to measure the electric parameters. Via the voltage and current mutual inductors, the measurements of transient value and voltage & current RMS, power and wattless power, energy etc. are complimented within a computation cycle. Further, power factor can be computed. The system hardware & software designs are exceedingly simplified. The network protocols are not implemented in the GPRS modem, it means that the TCP/IP stack must be implemented in the application system. Taking into account that networking data communication requires proper memory and CPU velocity, 32-bit ARM7TDMI architecture CPU is chosen as the system control and management core. Its abundant peripherial modules integrated on-chip implement seamless connection between CPU and GPRS modem and CS5460A. It further simplifies the system design. Networking communication protocols are essentially event-driven. It can't completely exert its functions without the services provided by OS(Operation System). Several factors being considered, the famous real-time kernel μC/OS-Ⅱis taken as system control & schedule kernel to make the whole system to work effectively. Because the TCP/IP stack are not embedded in the μC/OS-Ⅱkernel, according to the system requirements, a powerful, light weight TCP/IP stack –LwIP is ported to the μC/OS-Ⅱ,which includes complete PPP stack. If simple modem drive is added to the stack, a dial-up networking data transmission platform can be built up conveniently. Using the chosen components, hardware PCB is designed and manufactured. And the program is edited to test networking data communication. Its feasibility has been proven excellent.