1. Very sensitive transverse difference protection of the generator. The cross difference protection installed on the line connecting the two neutral points of the generator is used as the main protection against inter-turn short circuits, open branch welding faults and phase short circuits of the stator winding of the generator. generator.
2. Export logic to protect against horizontal differences. A highly sensitive cross differential protection operates at the trigger output. Once the generator rotor is grounded at one point, the protection switches to an adjustable delay.
3. Horizontal difference protection TA disconnection alarm. Under normal operating conditions, the third harmonic component is too small and is not easy to implement.
4. Vertical zero sequence voltage protection. The longitudinal homopolar voltage installed on theTV opening triangle dedicated to the generator output is used to protect the inter-turn short circuit of the generator stator winding. Since the protection adopts frequency tracking, digital filtering and full-cycle Fourier algorithm, the filtering ratio of zero-sequence voltage to third harmonics reaches more than 100, and the protection only reflects the component of fundamental wave.