Power grid signal parameter estimation method and system based on complex spectrum conjugate interpolation

• Main Authors: LIU QIAN, LI QINGXIAN, YANG SHUAI, DENG HANJUN, XIONG DEZHI, OUYANG JIE, XIE WEIFENG
• Format: Patent
• Language: Chinese; English
• Published: 02.06.2023
• Subjects: MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

The invention discloses a power grid signal parameter estimation method and system based on complex spectrum conjugate interpolation, power grid signal parameters in the estimation method comprise frequency, amplitude and phase, and the frequency estimation method specifically comprises the following steps: S1, obtaining an N-point sampling sequence x (n), and carrying out Fourier transform on the N-point sampling sequence x (n) to obtain N DFT spectral lines V [0], V [1],..., V [N-1]; s2, obtaining the spectral line with the maximum amplitude in the N DFT spectral lines, taking the index value of the spectral line as km, and then determining the index values k0, k1 and k2 according to a predetermined criterion; and S3, obtaining the power grid frequency based on the index values k0, k1 and k2 and the process coefficient. Wherein in the amplitude and phase estimation method, the DFT spectral line V [k1] with the maximum module value is selected for amplitude and phase estimation. According to the invention, i