VOLTAGE CONTROL BY TAP-CHANGING TRANSFORMERS FOR A RADIAL-DISTRIBUTION NETWORK

Voltage control is of interest to many researchers, and is currently b eing considered by many utilities for implementation in their energy c ontrol centres. Transformers with tap-changing facilities constitute a n important means of controlling voltage throughout the system at all voltage levels. A new method for determining the minimal changes in tr ansformer taps to control voltage levels is presented. The problem to be solved is cast into a nonlinear constraint optimisation. The constr aints are tackled in the minimisation algorithm;by forming the Lagrang ian. Necessary conditions for optimality are derived and solved using the Newton-Raphson method.