Physical Meaning of the Advantage of A-phi Method in Convergence

In this paper, we present numerical results confirming that the advantage of the A-phi method in the convergence of iterative solvers derives from the reduction of the error of the kernel of the discrete curl operator in the conductive region. We describe a fundamental theory for calculating errors. Using this theory, redundancies in the solution vectors in the A-method or the A-phi method can be processed. We can also define various errors that are used as a tool for examining both methods.