Thyristor controlled static compensators consist of two basic schemes, TCR and TSC. Owing to the discontinuous current in TCR, current harmonics are generated in the supply system. This paper introduces two methods for the reduction of these harmonics. On the basis of the coordination or uncoordination of turn ratios with harmonic reduction levels, each method is described in two alternative sc...

In this paper, a new approach is proposed for voltage and current harmonics compensation in grid-connected microgrids (MGs). If sensitive loads are connected to the point of common coupling (PCC), compensation is carried out in order to reduce PCC voltage harmonics. In absence of sensitive loads at PCC, current harmonics compensation scenario is selected in order to avoid excessive injection of...

This paper presents a new control method for simultaneous compensation of instantaneous reactive power and current harmonics by parallel active filters (PAFs). Reference compensating currents of PAF are calculated using the subtraction of instantaneous power from its average value. In this way, it is possible omitting high/low pass filter(s) from the control circuit of PAF, which usually result...

electric arc furnace (eaf) is one of the largest loads in electric power systems. it is highly time varying and nonlinear. its reactive power variations cause voltage fluctuations in nearby system which is known as flicker. on the other hand the nonlinear voltage-current characteristic causes strong voltage and current harmonics in eaf. to this end flexible ac transmission systems (facts) techn...

This paper proposes an improved control method based on modified Delta-Sigma Modulator (DSM) to enhance transient response and improve harmonic contents of buck DC-DC converter. The main advantages of the proposed method are improving the output voltage frequency spectrum, correction of the output voltage harmonic contents and sideband harmonics, reduction of switching noise peaks at the output...

nowadays with increasing use of numerous nonlinear loads, voltage and current harmonics in power systems are one of the most important problems power engineers encounter. many of these nonlinear loads, because of their dynamic natures, inject time-varying harmonics into power system. common techniques applied for harmonics measurement and assessment such as fft have significant errors in presen...

in this paper, the operation of helix traveling wave tube in interaction region is investigated by using a three dimensional large signal lagrangian model in frequency domain. the complete simulation of these tubes is essential for optimum design and minimum manufacturing cost. this 3d code can compute interception current (or current losses ), beam radius changes in interaction region and the ...

this paper presents an innovative active power filter design method to simultaneously compensate the current harmonics and reactive power of a nonlinear load. the power filter integrates a passive power filter which is a rl low-pass filter placed in series with the load, and an active power filter which comprises an rl in series with an igbt based voltage source converter. the filter is assumed...

Electric arc furnace (EAF) is one of the largest loads in electric power systems. It is highly time varying and nonlinear. Its reactive power variations cause voltage fluctuations in nearby system which is known as flicker. On the other hand the nonlinear voltage-current characteristic causes strong voltage and current harmonics in EAF. To this end Flexible AC Transmission Systems (FACTS) techn...

Harmonics in power distribution system are current or voltage that are integer multiples of fundamental frequency. For example if the fundamental frequency 50 Hz, then the 2-nd harmonics is 100Hz, the 3-rd is 150Hz, etc. A pure voltage or current sine wave has no distortion and no harmonics but non sinusoidal wave has distortion and harmonics. To quantify the distortion, the term total harmonic...