Load rejection

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Load rejection in an electric power system is the condition in which there is a sudden load loss in the system which causes the generating equipment to be over-frequency.

Electric power system

An electric power system is a network of electrical components deployed to supply, transfer, and use electric power. An example of an electric power system is the grid that provides power to an extended area. An electrical grid power system can be broadly divided into the generators that supply the power, the transmission system that carries the power from the generating centres to the load centres, and the distribution system that feeds the power to nearby homes and industries. Smaller power systems are also found in industry, hospitals, commercial buildings and homes. The majority of these systems rely upon three-phase AC power—the standard for large-scale power transmission and distribution across the modern world. Specialised power systems that do not always rely upon three-phase AC power are found in aircraft, electric rail systems, ocean liners and automobiles.

An electrical load is an electrical component or portion of a circuit that consumes (active) electric power. This is opposed to a power source, such as a battery or generator, which produces power. In electric power circuits examples of loads are appliances and lights. The term may also refer to the power consumed by a circuit.

Power outage loss of electric power to an area

A power outage is a short-term or a long-term loss of the electric power to a particular area.

A load rejection test is part of commissioning for power systems to confirm that the system can withstand a sudden loss of load and return to normal operating conditions using its governor. [1] Load banks are normally used for these tests.

Project commissioning application of a set of engineering techniques and procedures to check, inspect and test every operational component of a project

Project commissioning is the process of assuring that all systems and components of a building or industrial plant are designed, installed, tested, operated, and maintained according to the operational requirements of the owner or final client. A commissioning process may be applied not only to new projects but also to existing units and systems subject to expansion, renovation or revamping.

A governor, or speed limiter or controller, is a device used to measure and regulate the speed of a machine, such as an engine.

Load bank

A load bank is a device which develops an electrical load, applies the load to an electrical power source and converts or dissipates the resultant power output of the source. A load bank includes load elements with protection, control, metering and accessory devices required for operation. Load banks can either be permanently installed at a facility and permanently connected to a power source or portable versions can be used for testing power sources such as standby generators and batteries. Load banks are the best way to replicate, prove and verify the real-life demands on critical power systems..

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Load testing is the process of putting demand on a system and measuring its response.

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Combined cycle power plant type of power station

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Surface condenser Steam engine component which condenses excess steam for reuse as water

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