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Capacity factor measures the ratio of actual output over an extended period to nameplate capacity. Power plants with an output consistently near their nameplate capacity have a high capacity factor. For electric power stations, the power output is expressed in Megawatt electrical (MWe). For fuel plants, it is the refinery capacity in barrels ...
power rating is specified in terms of apparent power (KVA or MVA), since the exact power factor will be determined by the external factors; [5] power factor (PF) is the nominal power factor for other ratings; usually PF = 0.8; [5] insulation class (B, F, H) for the primary coil. Typical value is F, although older generators might use class B; [5]
The power factor in a single-phase circuit (or balanced three-phase circuit) can be measured with the wattmeter-ammeter-voltmeter method, where the power in watts is divided by the product of measured voltage and current. The power factor of a balanced polyphase circuit is the same as that of any phase. The power factor of an unbalanced ...
The actual production is also influenced by local factors such as dust and ambient temperature, which ideally should be low. As for any power station, the maximum possible power production is the nameplate capacity times the number of hours in a year, while the actual production is the amount of electricity delivered annually to the grid.
Capacity credit (CC, also capacity value [1] or de-rating factor [2]) is the fraction of the installed capacity of a power plant which can be relied upon at a given time (typically during system stress), [3] frequently expressed as a percentage of the nameplate capacity.
At higher speeds, the induction motor torque has to be limited further due to the lowering of the breakaway torque [a] of the motor. Thus, rated power can be typically produced only up to 130–150% of the rated nameplate speed. Wound-rotor synchronous motors can be run at even higher speeds.
The fixed speed wind turbines without a power converter (also known as "Type 1" and "Type 2" [5]) cannot be used for voltage control. They simply absorb the reactive power (like any typical induction machine), so a switched capacitor bank is usually used to correct the power factor to unity. [7] Capability curve of a photovoltaic generator
This ability to selectively control power factor can be exploited for power factor correction of the power system to which the motor is connected. Since most power systems of any significant size have a net lagging power factor, the presence of overexcited synchronous motors moves the system's net power factor closer to unity, improving efficiency.