Abstract: Along with the increasing demand on improving power quality i.e generally defined as any change in power (voltage, current, or frequency) that interferes with the normal operation of electrical equipment, the most popular technique that has been used is Active Power Filter (APF); This is because Passive filters performance is limited to a few harmonics and they can introduce resonance...

This paper presents a three-phase four-wire Shunt Active Filter that compensates power quality problems and can also interface renewable energy sources with the electric grid. The inverter stage of the active filter is based in a two-level four-leg inverter and its control is based in the Theory of Instantaneous Reactive Power (p-q Theory). The filter is capable of compensating power factor, un...

IIn this paper, a tunable single-amplifier biquadratic lowpass filter is presented. It consists of one balanced low-gain current amplifier and a second-order MOSFET-C feedback network. The filter was integrated in a double-poly 0.6 pm CMOS process and operates from a 3.3 V power supply. The pole frequency is tunable from 15.2 to 17.2 MHz, the pole Q is 3, the spurious-free dynamic range is at l...

This paper describes different power quality problems in distribution systems and their solutions with power electronics based equipment. A hybrid power filter in combined system of shunt passive and series active power filter has been designed and simulate with Matlab/Simulink. This filter is a three level PWM voltage source inverter and we use a fuzzy logic controller algorithm to control the...

This paper analyses the characteristics of LCL filter in active power filter (APF) and provides an accurate for mula to determine the resonant frequency of system. Based on a single-phase equivalent circuit model, a systematic approach to design APF with LCL filter is proposed. Total inductance is determined by the capability of APF. Moreover, damping ratio, resonant frequency and attenuation d...

purpose: to evaluate the role of active uveitis on refractive errors changes. methods: a cohort single group study was conducted on patients with acute or recurrent uveitis. cyclorefraction was performed in both phases of active and quiescent. sphere, cylinder and sphere equivalent power were compared in active and quiescent phases and analyzed statistically. results: sixty-six patients (eighty...