Kirchhoff’s current law states that for any electrical circuit, the algebraic sum of all the currents at any node in the circuit equals zero. In nodal analysis, if there are n nodes in a circuit, and we select a reference node, the other nodes can be numbered from V1 through Vn-1. With one node selected as the reference node, there will be n-1 independent equations. If we assume that the admittance between nodes i and j is given as Yij , we can write the nodal equations: Y11 V1 + Y12 V2 + … Y21