Sampling value product curve fitting detection algorithm used in custom power devies power devies

Custom power devices are used currently to deal with voltage sag and interruptions. Study on detection algorithm become urgent. In order to master sampling value product curve fitting detection algorithm, in theory, compared it with others detection algorithm, studied on DSP emulate system, achieved it's many merits ; in practice, used it in 10 kV SSTS, and validated it's quick utility chracteristic. Study it's localization, three results those larger calculation deviation brought by higher order harmonic component with identical amplitude, calculation result influenced little by allowable frequency deviation and less calculation deviation brought by more digit capacity of A/D transfer were achieved. From synthesis research, the final conclusions that, sampling value product curve fitting detection algorithm was more suitable to dispose voltage signal with better stability and less harmonic component in medium power system and special low-tension power system, and low-pass filter technology was used to detect voltage sag in low-tension power system with larger harmonic component by sampling value product curve fitting detection algorithm, were achieved.