Generator protection, calculating resistance for protection

Thread Starter

Lambo Av

Joined Apr 24, 2019
A 20kV, 100VA generator is protected by differential protection. 70% of the winding will be protected against the phase. What is the value of resistance to be located at the "Neutral to Ground" protection if the relay operates 30% out of the balance current?
Below are my steps to the solution. Is it correct? (I do not have the final answer, sorry)
If there is any mistake, mind pointing them out and explain what to correct on?