Power system harmonics estimation using adaptive Kalman filter and its nonlinear variants

Department of Electrical Engineering, National Institute of Technology Durgapur, Durgapur-713 209, West Bengal, India E-mail: pravir.yadav.15@gmail.com Manuscript received online 30 May 2020, revised and accepted 26 August 2020 This paper aims to investigate the efficacy of adaptive Kalman filers for power system harmonics estimation. Significant increment of non-linear loads is responsible for the presence of harmonics in power signals which deteriorates the power quality. Towards the improvement of power quality, estimation of the harmonic components is an essential task which has been proposed to be carried out by adaptive Kalman filter and its nonlinear variants. The paper investigates the suitability of adaptation algorithms for harmonics estimation and recommends an appropriate choice of adaptation algorithm. In addition to this, this paper presents a scheme of joint estimation of fundamental frequency along with the harmonic parameters using the nonlinear variants of Adaptive Kalman filter. From the relative performance comparison of adaptive nonlinear filters during harmonics estimation adaptive Cubature Quadrature Kalman filter is recommended for power system harmonics estimation for its performance accuracy, numerical stability and reasonable computation cost