ACCURATE DETECTION OF HARMONICS DUE TO NONLINEAR LOADS IN POWER SYSTEM NETWORK USING FFT ANALYSES

The main aim of this paper is to reduce the harmonic disturbances created by nonlinear loads; it has been a significant problem to maintain power quality. It is very essential to analyze power signal and find different harmonics. To finding the harmonic parts of some specific system currents and voltage references. Some harmonics are harmful to sensitive equipments and also cause power losses. In this paper, tries to finding the supply harmonics is downstream with relevance the nodes caused due to linear and nonlinear load. Here study the effectiveness of the concept with change in position of loads at corresponding nodes. The Fast Fourier Transform (FFT) is introduced with a new structure, capable of harmonic detection and type of load in single and three-phase systems. An analysis of the convergence of the FFT based on a linear and non-linear load under firing angles is presented. This algorithm is developed based on a design to find out the harmonics for combination of suspicious nodes. Systems with a more number of suspicious nodes, the system may divide into sub-system and the certain algorithm is applied to each sub-system to identify the harmonics. Simulations are carried out on performance analysis and to support the theoretical development. The decomposition of an input signal in its harmonic components using the Fast Fourier theory is based on previous knowledge of the signal fundamental frequency, which cannot be easily implemented with input signals with varying frequencies. In this scenario, the main contribution of this paper is the association of a FFT under the results showed the node combinations which are represent the harmonic sources yields an estimation error which approaches zero asymptotically