Tadahiro Goda

On-Line Modeling for Emergency Control Systems

Abstract In a stabilizing system, control actions are determined through stability analysis or contingency analysis. Therefore the on-line modeling method is a key technology in these analysis, and is closely inseparable with emergency control systems which make power system stable after a fault. The difficulty of the on-line modeling of an external system is caused by the lack of on-line data from the external system. In this paper, we summarize several on-line modeling methods for emergency control systems, and propose a new on-line modeling method which uses only local information after the fault.

Development and Field Experience of Digital Protection and Control Equipment in Power Systems

In applying microelectronic techniques to protective and control equipment in the power system, there is an important subject to be solved, which is the assurerance of long-term reliability. From this viewpoint, countermeasures against environmental conditions, for example temperature rise, electro-magnetic interference and dust are reconsidered.

Development of a predictive prevention method for the midterm stability problem using only local information

There has recently been a consolidation of power system stability in connection with the extension and complication of power systems, although unstable behavior after a serious fault has been expanding from the transient area to the dynamic area. We therefore undertook the development of a dynamic stabilization method based exclusively on local information. In this paper we propose a new concept of real-time modeling after a fault, using only local information. The control actions for stabilization of the power system are determined by behavioral prediction based on differential equations. The control actions of each generator are based on stability judgments at each local site. Case studies are presented to demonstrate the validity of the proposed method.