Study And Design Of Phase Meter With High Precision

With the development of science and technology, the phase measurement technique has gone deep into many fields and departments and it requires more and more precised.The purpose of subject is to achieve the phase difference measurement of two 50 Hz sine signals. Based on the further analysis about all kinds of phase measurement system, the research of phase measurement system for 50 Hz sine signals is made in the paper. According to the work flow, the entire system can be divided into several blocks: signal adjust model, data acquisition and management model, LCD display and data transmission units. These units can be subdivided single function parts, which are designed and tested respectively.The technique of digital signal processing(DSP) has been found to be an effective tool in phase measurement. This paper presents a solution for phase measurement using numeric zero-crossing and TMS320LF2407 16-bit fixed-point digital signal processor. In addition, the paper analyses the electronic circuits in detail. The input signals pass through the prepositive circuit which transforming the measured signals(voltage or current) into small voltage signals, the signal adjust circuit consist of programmable-gain amplifier and filter, and digital signal processor TMS320LF2407 for data acquisition and processing in turns. Provide the measuring results on LCD module. And also can transfer data to the PC's RS232 for farther analyse. The paper also analyses in detail main factors which influence the precision of phase measurement and come up with the methods of improving the precision of phase measurement.The application of advanced devices, new methods and latest technology to phase measurement results in dramatic improvement of function and precision of phase meter.