Power quality monitoring and analysis of industrial institutions and optimum harmonic filter selection

Key Words: Power Systems, Power Quality in Industrial Processes, Harmonic Analysis, Harmonic Filter Selection,Data Acquisition.The quality of electric energy used in industrial institutions plays a very important role in terms of having the electrical equipments work properly and efficiently. By the technology which is being developed days by days the loads of the system gain a number of varieties. The institutions want these loads to be linear. However, by the impact of a semiconductor technology, it is observed that there has been an increase in loads that are non-linear. Non-linear loads are the loads that have non-linear current and voltage characteristics. The damaging effects of machines which work in different institutions and have the same resources affect the other machines. Thus, this causes a number of characteristics which are not appropriate for the machines in the institutions.The loads and the system, cause harmonic currents and voltage. This harmonics are the primary damaging effects which destruct the quality of the electric energy. Harmonics give harm to the sinusoid formation of the mains energy. As a result, the electrical equipments cannot work properly. Industrial loads that cause harmonic formation such as electronic power elements, drivers, uninterruptible power supplies, inverters and high powered induction machines can be numbered. These harmonics also may be produce energy losses, heating and isolation problems and they shorten life of electronic elements. Therefore it is necessary to suppress of these harmonic effects before occurrence and afterwards.In this study a harmonic analysis has been realized from parameters which are gathered from high sample frequencies from various industrial institutions which have a variable load characteristic in order to gather data, electric signals gathered from current and voltage transducers were loaded on a computer by a data acquisition card. In order to monitor the power quality and record the data a visual user which has a LabVIEWTM data base was designed. The software helps to monitor the waveform, total harmonic distortion level and changes in power parameters. The data gathered for a harmonic analysis which belongs to different working conditions, different industrial institutions were analyzed by MATLAB. The signals of time domain were analyzed in the frequency domain and the phase data output was taken, for the dominant harmonics, filtration has been suggested.Also, an artificial neural network based intelligent monitoring system has been designed for harmonics.