Optimal reactive power control for industrial power networks

Manufacturing processes that have several main buses that supply power to other areas of the plant have to ensure the voltages on the buses remain close to the desired value. If the voltage should drop there could be loss of process functions due to under voltage tripping of motors, pumps etc. In addition, the utility often imposes a penalty for low tie line power factor. By controlling the bus voltages close to desired values while keeping tie-line power factor close to unity, reliability of plant operation is increased while minimizing costs. The authors describe a reactive power optimisation method based on the Simplex Self Directing Evolutionary Operation (SSDEVOP) method proposed by Box (1957). The construction of a static load flow analysis (SLFA) admittance matrix and network configuration adjustments are discussed. The implementation of the system, off-line SLFA program overview, the distributed control system environment and three case studies are also discussed.