FormulasΒΆ

\[\begin{split}\sf \left[ {\begin{array}{cc} \sf Y_{VV} & \sf Y_{VI} \\ \sf Y_{IV} & \sf Y_{II} \\ \end{array} } \right] \left[ {\begin{array}{c} \sf \underline V_k \\ \sf \underline V_u \\ \end{array} } \right] = \left[ {\begin{array}{c} \sf \underline I_u \\ \sf \underline I_k \\ \end{array} } \right]\end{split}\]
\[\sf \underline V_u = Y_{II}^{-1} \left( \underline I_k - Y_{IV} \underline V_k \right)\]
\[\sf \underline I_u =Y_{VV} V_k + Y_{VI} \underline V_u\]
\[\begin{split}\sf \underline V_p = V_u[m] \\ \sf \underline I_p^{pq} = \frac{\vec S_p}{\vec V_p} \\ \sf i\; in\; a,b,c\end{split}\]