Reasons and countermeasures for computation failures of continuation power flow

The classification, reasons and countermeasures of the computational failures of continuation power flow are proposed in this paper. The computational failures can be divided into the turning point failures and the non-turning point failures. The reason of the turning point failure is that the global parameterization such as arc-length or pseudo arc-length parameterization cannot overcome the singularity of Jacobian matrix for some voltage instability cases with strong local characteristic. The reason of the non-turning point failure is that some nonsingular points of original system are translated to the singular points of the extended Jacobian matrix by the parameterization process. Two countermeasures are proposed to handle the failures. The local parameterization is used instead of the global parameterization to avoid the turning point failure and a forced parameter switching strategy is used to overcome the non-turning point failures. Case studies with a practical 3000-bus power system indicate that the proposed countermeasures are very efficient