Assessment of voltage stability and static ATC with expanded NR-S and CPF-GMRES

Abstract

Voltage collapse is an event that causes major concern to the power system utility nowadays. The effect can be catastrophic to the power system where it can cause total collapse to the operation of the system. The study of the voltage collapse phenomenon can provide way to prevent this event from happening. Static analysis provides the best way to study this phenomenon and there had been many methods developed to study the criteria of this phenomenon. Conventional Newton Raphson method has the singularity problem on its Jacobian matrix and thus could not give the solution. To overcome this problem, many methods had been proposed that can avoid the problem and one of them is the Continuation Power Flow (CPF) method. CPF method is a very powerful method that can give the solution without having the singularity problem. The CPF method is improved using the new CPF-GMRES (Generalized Minimum Residual) method. As practically NRS (Newton – Raphson – Seydel) is an old method but it is a fast and accurate one. This paper expands NRS method and proves that the Expanded NRS is more reliable and faster than CPFGMRES and NRS. The idea is demonstrated on 350 bus network in IRAN (Khorasan region).