Accuracy of synchrophasor measurements provided by the sine-fit algorithms

The paper analyzes the accuracies of both the half-cycle and one-cycle synchrophasor estimators provided by the three and four-parameter sine-fit algorithms when off-nominal frequency offset, amplitude modulation, and phase modulation occur. The test conditions comply with the IEEE Standard C37.118.1-2011 for synchrophasor measurements for power systems. The algorithm accuracy is evaluated in terms of the Total Vector Errors (TVEs) expressed as a function of the relative error in the a-priori available sine-wave frequency estimate used as input to the algorithms. The achieved TVEs are compared with the related accuracy threshold specified in the Standard. From this comparison some interesting conclusions concerning advantages achieved by applying the sine-fit algorithms to synchrophasor measurements are drawn.