Zaichenko Y.M. Adaptive control of the active power filter with selective harmonic compensation properties. – Manuscript
Dissertation for the candidate of technical science degree in specialty 05.09.03 “Electrotechnical Complexes and Systems” (141 – Electric Power Engineering, Electrical Engineering and Electromechanics). – National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, 2020
In the dissertation the shunt active power filters control systems are developed. Сurrent harmonics staff estimation is based on observer which utilize idea of division three-phase signal into harmonics of the positive, negative and zero sequences. This observer provides harmonics estimation and compensation current reference calculation.
In order to achieve fast convergence together with selectivity properties of harmonic estimation novel observer tuning procedure is proposed. The dynamic behavior and selectivity properties are investigated by simulations. The proposed tuning procedure simplify practical implementation of harmonic observer by reducing requirements for the computing performance of the controller.
A novel observer with taking into account the presence of phase shift caused by hardware current signal filtering is developed. The observer designed in this way provides the detection of harmonic distortions in a given frequency range, but has no selectivity properties.
Based on the active power filter model, two active power filter current control algorithms, which allow to compensate for harmonic distortion and reactive current, are developed. The first algorithm is based on a separation of harmonic detection and current regulation processes. A new nonlinear algorithm for the active power filter current control, which guarantees asymptotic current tracking and does not require “high” gains, has been developed. From the simulation results it follows that the proposed solution provides asymptotic tracking of the filter currents. The developed current controller is simpler in terms of practical implementation and provides high noise immunity. The second algorithm is the adaptive system for harmonics estimating and current control. This approach is suitable in the case when one need to evaluate and compensate for harmonics in a given range of frequencies.
A method for the SAF DC link voltage control, which provides partial linearization of the voltage subsystem and asymptotic control of the average DC link voltage have been developed.
New algorithm for active power filter current control, which allow to take into account variations of active resistance and inductance of the output filter of the active filter, have been developed. The developed active filter control system do not require a long adjustment process, which is inherent in the industrial active power filters.
The developed observers and controllers are implemented in the prototype of the active power filter, which is based on digital signal processor TMS320F28335. The conducted experimental investigations proved the presented theoretical results.
The results of the work are implemented: in the electrical power quality improvement systems by the company “Technoserviceprivod”, Kyiv, in the educational process at the National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”
Keywords: active power filter, electrical power quality, higher order harmonics, reactive power compensation.