A powerful Automatic Generation Control (AGC)-type power- systems model/simulator will be developed under this proposed project. The simulator development will require structuring the model components using time-scale separation methodology, development of appropriate transmission plant thermal models and of bus voltage control device models, and developments in network processing techniques. The result will be a PC-based AGC-type simulator that not only will combine the major advantages of the engineering-class and training-class simulators, without disadvantages of each, but will go beyond the state of the art in providing a tool for across-the-board analysis of all relevant phenomena in the AGC frequency range. The extended AGC simulator will provide unparalleled capabilities for the study of power system operation and the effectiveness of potential AGC and voltage control algorithms. It will be useful to power system engineers, to universities for teaching and research, to power system operators, and to utilities and vendors for evaluation of AGC offerings.