Modelling of adjustable speed AC drives for harmonic studies using Kalman filtering algorithm

AC adjustable-speed drives (ASDs) have become the primary choice for most new and retrofit precision motor-control applications with increased system efficiency and reduced system losses. The significant increase in the use of ASDs brings the need for understanding compatibility issues between them and their electrical environment in order to design the electrical systems appropriately. A three-phase equivalent circuit model is developed to model adjustable speed drives (ASDs) for power system harmonic analysis by impedance model using Kalman filtering algorithm (KFA). The validity and accuracy of the model were validated by comparing Fast Fourier transform (FFT) from simulation results with equivalent impedance model using KFA. Theoretical derivations and simulation results are presented in this paper.