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POWER QUALITY SOLUTIONS

There are four ways to solve power quality problems:

1- Design equipment and electrical systems to prevent electrical disturbances from causing equipment or systems to malfunction. Where, manufactures of sensitive equipment can reduce or eliminate the effect of power quality problems by designing their equipment to be less sensitive to disturbances. They can add some devices to their equipment according to situation, for instance a capacitor to provide temporary energy storage when the voltage sags are too low. They can also alter their equipment to desensitize it to power quality problem for example; they can design special K factor transformers that tolerate harmonics.
2- Analyze the symptoms of power quality problems to determine its cause and solution. It is important to determine source and type of power quality problems, the type of power quality problem and its cause often determine the solution.

3-Identify the medium that is transmitting the electrical disturbances and reduce or eliminate the effect of that medium.

4- Treat the symptoms of the power quality problems by use of power conditioning equipment. It provides essential protection against disturbances. Power conditioning equipment include devices that reduce or eliminate the effect of a power quality disturbance. It can be used to condition the source, the transmitter, or the receiver of the power quality problems. The equipment can be divided into ten categories, surge suppressors, noise filter, isolation transformer, low-voltage line reactors, various line voltage regulators, motor-generator sets, dual feeders with static transfer, uninterruptible power supplies, harmonic filters and Dynamic voltage restorer (DVR).

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