What are the hazards of high or low power factor in diesel imported generator group operation?

What is the capacity factor? Usually, when a current passes through an appliance, it consumes a certain amount of electrical energy to convert it into other forms of energy. The consumed electrical energy consists of two parts, one is the active power actually used by the appliance, and the other part is the reactive power consumed by other aspects of the appliance application. Capacity factor is the percentage of active power in the apparent capacity. The greater the power factor, the higher the effective utilization of power, but not equal to 1.

1, diesel imported generator in operation, capacity factor is too high, that is, the reactive power is too low. Reducing the reactive power margin of the system will affect the steady state integration of the imported generator. Although the cost has been optimized, from Cummins’ point of view, it is to increase the probability of accidents. In the event of a sudden accident, the generator cannot withstand small perturbations or vibrations and may lose step.

When the power factor increases, the reactive power capacity decreases (when the capacity factor is 1, the reactive power capacity is 0). In this case, the excitation current decreases, and the suction between the rotor and the stator pole decreases, thus destroying the static stability of the generator. When the Cummins power capacity factor decreases, the reactive power increases. Due to the induction reactive power demagnetization, in order to keep the stator voltage unchanged, it is necessary to increase the excitation current, thus increasing the temperature and overheating of the rotor windings.

In addition, low reactive power will cause voltage drops at the generator terminals and affect the auxiliary generator. The current absorbed by the generator rises, lowering the voltage, creating a vicious cycle that can cause the entire system to collapse. During the advance phase of the generator, the ends are light and hot.

In addition, the greater the capacity consumption in the transmission process, the greater the generator consumption. A low capacity factor increases the voltage at the generator end, increases the flux density in the core, delays consumption, and raises the core temperature. When operating under rated load, if the power factor of the generator is too low, the force will be limited, and the compliance of the generator will be greatly reduced.

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Post time: Sep-29-2022