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High Z Generator Diff Protection

Thread starter veritas
Start date Oct 6, 2014

Status: Not open for further replies.

Oct 6, 2014

veritas

Electrical

I am contemplating using high-z diff protection for a 660MW generator. Using biased diff requires enormous CT's due to the very high fault levels. High-z diff require the Ek to be a minimum of twice the stability voltage settings which is much lower than the Ek required for biased diff. The 23kV generator is connected to a 330kV grid. Has anyone applied high z to a gen and if so anything to look out for? Relays used?

Thanks.