A state estimation algorithm for identification and measurement of power system harmonics

Abstract Electrical power networks may be subject to harmonic injection due to the presence of non-linear loads or sources such as converters of all kinds, including HVDC transmission and solid state switching for static VAR systems, and also due to increased use of variable speed motors, dimmer switches, microwave ovens, battery chargers, etc. This paper presents a new application of the least squares parameter estimation error algorithm for the measurement and identification of power system harmonics. The proposed technique uses the digitized bus voltage and current to identify the source, order and amplitude of the harmonic signals. The mathematical model for the algorithm is presented; the effects of data window size, sampling frequency and time reference are also examined.