The Research And Design Of Embedded Power Quality Monitoring Terminal

Power is a kind of important energy, the quality of which not only relates with people' life, but also relates to the whole interests of natinal economy. In a sense, the quality of the electricity reflects the situation of one country's economy and technology. In order to build our country into a conservation oriented society, it appears particularly important that supervising the quality of the electricity.In this paper, considering that the system will acquire and process a large number of data, and at the same time, in order to meet the requirements of real-time, the design is proposed based on ARM+DSP+CPLD dual CPU architecture ultimately under comprehensive comparing advantages and disadvantages of several original design methods. Modular designing ideas are adopted in hardware department, and the main design includes that the pre-gathering data module using AD7656 as the core chip, the DSP data processing module using TMS320VC5402 as the core chip, the ARM controlling management module using S3C2410 as the core chip. The HPI interface belonging to TMS320VC5402 itself is adopted to realize the communication between the DSP and ARM. The DM9000 Ethernet interface circuit is designed to achieve the remote monitoring of power quality, Simultaneously, the related circuit board is designed and debugged. In software department, it includes that the software design of DSP data processing module and ARM master management module. The flow chat of program is presented in the DSP data processing module, and the software design of ARM master management module is introduced in great detail in the paper.In data sampling, the CPLD is responsible for logic controll. The FSM is designed by using VHDL language to realize controlling the A/D conversion and data storage. In data processing, by the simulating of real-time signal processing in MATLAB, it is verified that the theoretical correctness of resolving the difficult problem such as reducing spectrum leakage to detect the harmonics by FFT after synchronous sampling by phase-locked multiplier circuit.Finally, the Qt/X11 and Qt/Embedded graphics development tool is installed successfully, and the GUI interface of the monitoring terminal is designed in the paper to achieve the purpose of remote monitoring and analysis of power quality.