The relation between the old and new per unit impedance values is given by:
1
\(Z_{pu}^{new} = Z_{pu}^{old}\frac{{S_B^{old}}}{{S_B^{new}}}{\left( {\frac{{V_B^{old}}}{{V_B^{new}}}} \right)^2}\)
2
\(Z_{pu}^{new} = Z_{pu}^{old}\frac{{S_B^{new}}}{{S_B^{old}}}{\left( {\frac{{V_B^{old}}}{{V_B^{new}}}} \right)^2}\)
3
\(Z_{pu}^{new} = Z_{pu}^{old}\frac{{S_B^{new}}}{{S_B^{old}}}{\left( {\frac{{V_B^{new}}}{{V_B^{old}}}} \right)^2}\)
4
\(z_{pu}^{old} = Z_{pu}^{new}\frac{{S_B^{new}}}{{S_B^{old}}}{\left( {\frac{{V_B^{old}}}{{V_B^{new}}}} \right)^2}\)