By Hans De Keulenaer / Published on Tue, 2008-09-09 10:07
The problem of voltage sags and Swells and its severe impact on sensitive loads is well known. To solve this problem, custom power devices are used. One of those devices is the Dynamic Voltage Restorer (DVR), which is the most efficient and effective modern custom power device used in power distribution networks. Its appeal includes lower cost, smaller size, and its fast dynamic response to the disturbance. This paper describes DVR principles and voltage restoration methods at the point of common coupling (PCC ).
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By Angelo Baggini / Published on Mon, 2008-03-10 17:42
During normal operation supply voltage is provided by the network to the load at rated value.
In the event of a voltage dip, it is possible to maintain rated voltage by installing a dynamic voltage restore.
This animation shows the principle of automatic voltage dip mitigation equipment's operation.
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By Hans De Keulenaer / Published on Wed, 2008-01-16 14:09
By A K Ramasamy et al
A Dynamic Voltage Restorer (DVR) is a custom power device that is used to compensate voltage sag.
The DVR generally consists of voltage source inverter (VSI), injection transformers, passive filters and energy storage (battery). The efficiency of the DVR depends on the efficiency of the control technique involved in switching the inverters. The inverters are switched using Space Vector Pulse Width Modulation pulses (SVPWM) to maximize the usage of DC link voltage.
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By Hans De Keulenaer / Published on Wed, 2008-01-16 14:03
By Z L Liew et al
The paper presents a Dynamic Voltage Restorer (DVR) system using a three-dimensional space vector pulse width modulation (3D-SVPWM).
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By Hans De Keulenaer / Published on Wed, 2008-01-02 18:03
A power quality case study
By Michiel Van Lumig, Laborelec
Various departments at a car manufacturing plant are suffering from regular process outages due to voltage dips. These dips are causing production losses in the Metal Operation, Spray Coating, and Assembly departments that directly affect the productivity of the plant. The cost of those losses is directly related to the profile of the voltage dip (duration and depth).
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By Hans De Keulenaer / Published on Mon, 2007-11-26 18:16
By Y Zhang et al
This paper aims to provide both utilities and customers with a methodology to investigate their sag performance with incorporated mitigation devices. The sag performance is valued technically and financially, and presented by ‘generalized sag table’ and ‘annual sag losses’ respectively. By applying this approach, new indices for both supply system and load buses can be drawn. The paper also presents an example to illustrate the applicability of proposed methodology.
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By David Chapman / Published on Wed, 2006-12-20 01:00
Both are used to mitigate the effects of voltage dips. Dips are characterised by the depth - the retained voltage - and the duration. Short and deep dips are best served by a DVR while long and shallow dips are the province of the voltage regulator.
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By Hans De Keulenaer / Published on Mon, 2006-03-20 12:05
In this compact webcast, Marcel Didden from Laborelec shares a wealth of information and experience. If you're considering investment in a mitigation solution, this may be one of your best 15 minutes ever spent.Installing a UPS is in theory the easiest way to protect sensitive equipment to voltage dips. However, due to their considerable purchase and maintenance costs, UPS's are only installed on a structural basis with installations where the costs resulting from power supply problems are very high such as in hospitals or financial institutions.
Triggered by problems in industrial processes containing variable speed drives, solutions to protect equipment only against voltage dips are now commercially available. This webcast analyses the technical and economic considerations of different options to protect specifically against voltage dips, such as: Dynamic Voltage Restorer (DVR), Flywheel, Statcom and Active Front End.
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