Reduced modified nodal approach to circuit analysis

Although the modified nodal approach (MNA) has been widely used for formulating circuit equations, several limitations exist in this method including zero diagonal entries in its matrix and redundant variables like voltage source currents. Here, a new method of circuit equation formulation called "Reduced Modified Nodal Approach" (RMNA) is proposed, in which node voltages and controlling currents are adopted as the circuit variables. The circuit equations of the RMNA are formulated directly and systematically from a given circuit through three types of pivotings. In the RMNA matrix, its size is equal to the number of nodes in the circuit augmented by the short-circuit branches (SCB\´s) and zero diagonal entries are avoided.