Automatic overfrequency limitation

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ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
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Section 3. Protection and automation

Automation and telemechanics. Automatic overfrequency limitation

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Encyclopedia of radio electronics and electrical engineering / Rules for the installation of electrical installations (PUE)

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3.3.84. In order to prevent an unacceptable increase in frequency at thermal plants, which may be operating in parallel with hydroelectric power plants of much higher capacity under load shedding conditions, automatic devices should be used that operate when the frequency rises above 52-53 Hz. These devices should primarily act to turn off part of the HPP generators. It is possible to use devices that act on the separation of thermal power plants with a load, if possible, corresponding to their power, from the hydroelectric power station.

In addition, at the nodes of the power system containing only HPPs, devices should be provided that limit the emergency increase in frequency by 60 Hz by turning off part of the generators to ensure the normal operation of the motor load, and at nodes containing only TPPs, devices that limit the long-term increase in frequency by the value , at which the load of power units does not go beyond their control range.

See other articles Section Rules for the installation of electrical installations (PUE).

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