| Title |
Improved Direct Method for Calculating the Closest Voltage Collapse Point and Voltage Stability Enhancement by Generation Redispatch |
| Authors |
남해곤(Nam, Hae-Kon) ; 송충기(Song, Chung-Gi) ; 김동준(Kim, Dong-Jun) |
| Keywords |
voltage stability ; closest saddle node bifurcation ; direct method ; left eigenvector ; generation redispatch |
| Abstract |
The distance in load parameter space to the closest saddle node bifurcation (CSNB) point provides the worst case power margin to voltage instability and the left eigenvector at CSNB identifies the most effective direction to steer the system to maximize voltage stability under contingency. This paper presents an improved direct method for computing CSNB: the order of nonlinear systems equations is reduced to about twice of the size of load flow equations in contrast to about three-times in Dobson's direct method; the initial guess for the direct method is computed efficiently and robustly by combined use of continuation power flow, a pair of multiple load flow solution with Lagrange interpolation. It is also shown that voltage stability may be enhanced significantly with shift of generations in the direction of the left eigenvector at CSNB. |