1998 Volume 118 Issue 1 Pages 15-22
This paper investigates a multimachine control system based on the modern control theory to enhance the stability of a local multimachine power system connected to a large-scale primary power system. Most modern control theory-based designs have been proposed on the assumption of an infinite-scale primary power system, while in most actual power systems fairly large voltage and phase fluctuations are induced by various kinds of system's faults. The local multimachine control system is then designed so as to be very effective in controlling the disturbances from the primary power system. The design is improved by using no assumption of the infinite-scale primary system. In the system design, moreover, a decentralized multimachine control system is proposed so that the control system for each machine can be designed independently from the others. It is demonstrated by computer simulations that the proposed system is effective and robust in stability enhancement by using an example of local power systems even when some fluctuations in the primary power system exist.