Research On Reactive Power Compensation And Harmonic Suppression Methods Based On Fft

With the deepening of oil field development, oil and gas production of electricity more and more dependent, especially for power quality have become increasingly demanding. Power quality problems can be divided into voltage quality and current quality of the two major aspects. Voltage will affect the quality of the user equipment refers to the normal operation of the system voltage is not ideal, including voltage flicker (Flick), transient over-voltage (Swell), harmonic distortion (Harmonics), the phase voltage imbalance (Unbalance), etc. ; current power quality refers to non-linear loads such as electronic equipment brought to the power grid current distortion, including the inflow of the grid harmonic current surge transients, as well as reactive power, unbalanced load current, low-frequency load change such as flashing.Oil extraction plants in the area power grid, because of the emotional load of the main three-phase asynchronous motor, with the result that oil the lower the power factor, energy waste, while in power system operation, power loss and power loss is inevitable , but it should be possible to adopt measures to reduce the wear and tear, this save resources, reduce energy costs and improve equipment utilization, etc. is very important.Because there are dificulfies in performing synchonized sampling and integral period truncation in theharmonic an alysis of power system with the fast Fourier trmmform technique.However, not to satisfy these conditions,the results will be disturbedby the frequencyleakage.Some efforts have been made including the utilization of window functions and interpolation algorithms to correct the measured frequency,phase and amplitude by FFT.In order to overcome some shortcomings of exsting correction methods,an improved algorithm is present in this paper to be applied in the oil fild ,with which the amplimde of harmonics Can be estimated from the two neighboring spectral lines.The polynomial approximation method is also employed to obtain simple formulas for frequency an d amplitude correction.By these methods,the disturbance of the frequency leakage an d the noise can bereduced and the accuracy of the harmonic an alysis can be improved.Based on the propo sed algorithm,the practical correction formulas for some typical window functions are developed. The simulation results have verified theefectiveness andpracticabifity ofthe algorithm.