Maximally Flat-Frequency-Response Multiple-Resonator-Based Harmonic Analysis

Dynamic Phasors Estimation Based on Taylor-Fourier Expansion and Gram Matrix Representation

“…The same situation is for subharmonics components on 20 Hz. The obtained results are better than the results obtained in [5,39].…”

“…It can be concluded that the error occurring is above all the results of the introduced delay, similar to that of [15,21]. Owing to the modification made in calculating the parameters of the phasors, the magnitudes of this calculated error are smaller than in other methods based on the least squares method, with their size becoming comparable to [16,17,23,38], therefore being much smaller than [27,[39][40][41]. The proposed approach can calculate the derivatives of the phasor-phasor speed and acceleration, which reduces the estimation error.…”

“…The proposed approach in estimation of phasor values was also tested in a situation when processing the input signal contains the third harmonic with amplitude settled to 20% of the fundamental component, and an interharmonic frequency 75 Hz. This level of the harmonics is very commonly present in current waveforms in the control applications such as a current tracking in shunt active power filters (APFs) in marine networks or smart distributed grids with renewable energy sources [39]. TVE in estimation of third harmonics in this test was about 1%.…”

“…The hardware features of the following characteristics were used: Intel(R) Core(TM) i5-4460, 3.2GHz, 16 GB RAM. The proposed modification in the algorithm described here showed that the time required for the calculation was significantly less than in other methods based on the least squares method [24,27], and approaching the speed by methods [22,23,[39][40][41].…”

“…In order to obtain an even more complete picture of the performance of the phasor estimation method described here, a subharmonic frequency of 20 Hz, as well as two interharmonic components frequency of 57.5 Hz and 85 Hz [5], with a 10% amplitude with respect to the fundamental component amplitude, has been added to a sinusoidal signal with the aforementioned contents. An out-of-band interference test is defined to test the capability to filter interfering signals that could be aliased into the measurement, and it is considered only for M class and it is eliminated for P class [39].…”