Research On Power Frequency Distortion Instrument Base On Digital-analog Multiplication OCF

In the electric power system, as the existence of non-linear loads users, low-voltage equipment and household appliance increase the steady in the power supply system. There is a negative influence on the power system itself and other electrical equipments. The production of the harmonic is a kind of signal distortion. Distortion factor meter is an instrument that used to measure the degree of signal distortion. Although the distortion measuring instrument has applied widely in Power sector, Electronics, Communication Engineering and other fields, there are still some flaws in the design methods.First, this article introduced several methods of the design of Distortion factor meter. Such as fundamental suppression method, harmonic analysis (FFT method), curve fitting method. Through analysis sever measuring distortion methods deeply, I found they all had strengths and weaknesses. Second, after described and analysis the characters and technique that based on analog—digital multiplication optimization correlative filter this dissertation. Then a new method was put forward to designing frequency signal distortion measurement system .The measurement system is based on analog—digital multiplication optimization correlative filter in this dissertation.Meanwhile, the D / A finite word-length and zero-order sample holding the affects on analog-digital multiplication OCF have done a deeply analysis. Third, measurement system hardware circuit has been designed base on the principle of analog-digital multiplication OCF. Then, the simulation results of the principle of analog-digital optimism multiplication OCF which is applied on measuring the frequency distortion by the use of MATLAB / Simulink simulation tool, then the result is given.Through the simulation results and analysis proved there is a strong anti-jamming capability and high accuracy in analog—digital multiplication optimization correlative filter, achieve the accurate measurement of signal distortion, and can achieve the accurate measurement of signal distortion.