Zero-IF receiver has some advantages, such as small factor, low cost and easily integrated on a chip. They make it competitive of RF receivers. However, DC Offset and flicker noise, etc., have profound effects in zero-IF receiver, which need not be considered in super-heterodyne receiver. Following a major study of flicker noise, possible solutions are given, especially those based on the passi...

Abnormal increase of low frequency flicker noise in analog nMOSFETs with gate oxide in valence band tunneling domain is investigated. In 15Å oxide devices, valence-band electron tunneling from Si substrate to poly-gate occurs at a positive gate voltage and results in the splitting of electron and hole quasi Fermi-levels in the channel. The excess low frequency noise is attributed to electron an...

Abstrac t In the paper a virtual instrument for power quality measurement and research is proposed. The instrument is divided in several modules which provide generation, measurement and recording of the typical power quality (PQ) disturbances such as: harmonics, voltage dips, interruptions, flicker, unbalance etc. The virtual instrument allows setting different measurement parameters which exp...

The detection and classification of power quality events that disturb the voltage and/or current waveforms in electrical distribution networks is very important to generate energy deliver this end-user equipment at an acceptable voltage. Various property extraction methods are used determine type disturbances signal. In study, seven distortions including sag, swell, harmonics, sag with swell fl...

A new instrument for the evaluation of disturbances caused by variations in lamp voltage (light flicker) is proposed, based on light intensity measurements. Unlike current standard (IEC EN 61000-4-15), which determines flicker severity by filtering powering voltage measurements with a standard lamp model (230V/60W), the presented methodology includes the lamp itself in the measurement process, ...

This paper proposes an on-line neural network based Distributed Static Compensator (DSTATCOM) for a three-phase, three-wire grid connected distribution system to mitigate the voltage flicker. The technique is based on instantaneous tracking of the voltage envelope and phase angle using online neural network based estimator. These estimated values are used by neural controllers to compute inputs...

A novel method to mitigate voltage flicker problem usually caused by DC Arc Furnaces has been presented in this paper. This method called Direct Current Ripple Re-injection is applied to a multi-step switching reactor in the output of the AC/DC converter to make the output load current as smoother as possible. This method would lessen harmonic effects properly. The proposed approach is simulate...

Voltage fluctuation is one of the important types of power quality aspects originated from heavy fluctuating loads. This phenomenon can influence the behavior of induction motors, produce excessive vibration and increase the ohmic losses. In this paper a simplified model to evaluate the electrical characteristics of three phase induction motors under voltage fluctuation conditions will be prese...

Wind-energy systems cause fluctuations more than any other sources and hence, voltage fluctuations are expected with these units. This paper addresses the problem of voltage fluctuation caused by doubly fed induction generators (DFIG)-based variable-speed wind turbines. Flicker emission of these units is investigated during continuous operation. The effects of grid strength, angle of grid imped...