Active filtering of electric power has now become a mature technology for harmonic and reactive power compensation in two-wire (single phase), three-wire (three phase without neutral), and four-wire (three phase with neutral) AC power networks with nonlinear loads. This paper presents a comprehensive review of active filter (AF) configurations, control strategies, selection of components, other related economic and technical considerations, and their selection for specific applications. It is aimed at providing a broad perspective on the status of AF technology to researchers and application engineers dealing with power quality issues. A list of more than 200 research publications on the subject is also appended for a quick reference.

A review of active filters for power quality improvement

This paper documents the modeling of harmonic sources with nonlinear voltage-current characteristics such as transformers, iron-core reactors, rotating machines, arc furnaces, energy efficient lightings, and some household electronic appliances. The harmonic generating characteristics of these apparatus are reviewed. Different modeling techniques are summarized and suggestions for the use of different models are also provided whenever possible.

Modeling devices with nonlinear Voltage-current Characteristics for harmonic studies

This paper presents an active filter using the synchronous detection method. The equal current synchronous detection method is applied to calculate the reactive and harmonic current compensation components for triggering an active power filter in an unbalanced three-phase power system. The simulation and experimental results show that active filter operation using the synchronous detection method is effective to eliminate line current harmonics and compensate the reactive current component. The merits of the proposed method are its capability to operate under an unbalanced three-phase system by perphase calculation, to avoid conversion error by force waveform calculation, to balance the unbalanced load and to accomplish good performance by very simple implementation. >

An active filter for unbalanced three-phase system using synchronous detection method

A new parallel processing uninterruptible power supply (UPS) configuration is proposed in this paper. It provides active power line conditioning to minimize mains current distortion. This performance is superior to a conventional UPS. A prototype has been implemented and tested to verify its performance. The experimental results show that the input power factor of the proposed UPS is nearly unity, and the total harmonic distortion (THD) of the input current under nonlinear loading is only 3.618% for a mains voltage with THD of 1.633%.

A new UPS scheme provides harmonic suppression and input power factor correction

https://www.daaam.info/Downloads/Pdfs/proceedings/proceedings_2014/155.pdf

Investigation Performance of Marine Equipment with Specialized Information Technology

This paper presents the design of an electronic compensator that can compensate the reactive current drawn by an arc furnace. Consisting of three independent single-phase pulse-width modulated (PWM) inverters, the proposed compensator responds quickly to any sudden load changes and compensates both the fundamental displacement current and the harmonic distortion current drawn by the load. Unlike conventional static var compensators, the electronic compensator can also supply the active current demanded by the load if an energy source independent of the utility is available. Simulations are conducted, including the modelling of the furnace current and voltage waveforms during the early stage of scrap melting, in order to determine the effectiveness of several suggested detection methods that can be used to separate the active and reactive components of the furnace current. Actual waveforms observed on a local furnace are included that corroborate the computer modelling. Experimental results indicate that the electronic compensator equipped with a suitable detection circuit can accurately compensate an arc furnace.

A. Mirbod

Papers

A New Static Var Compensator for an Arc Furnace