Frequency response analysis is the technique whereby a sinusoidal test signal is used to measure points on the frequency response of a transfer function or impedance function. Sweep Frequency Response Analysis (SFRA) testing provides insight into the mechanical and electrical integrity of transformers.
Main Purpose of SFRA Test: Transformer Core displacement Winding displacement for both rotor and transformer Broken or loosen clamp connections Inter turn short circuit Internal short circuit Winding to Core Earth fault Winding Open circuit condition
The tendency of a Reach of Distance Relay to operate at impedance larger than its setting value is known as overreach. Overreach is the presence of d.c. offset in the fault current wave, as the offset current has a higher peak value than that of a symmetrical wave for which the relay is set.
Bus Type - Known Parameter - Unknown Parameter Load Bus -P, Q - V, phase angle Generator Bus - P, V (magnitude) - Q, Voltage phase angle Slack Bus Voltage - magnitude and phase angle - P, Q
For the cut-in speed is the point at which the wind turbine is able to generate power. Between the cut-in speed and the rated speed, where the maximum output is reached, the power output will increase cubically with wind speed. Pmax directly propotional to cubical of wind speed. So, by double the speed of wind power will be increased by 8 times.