STUDY OF THE INFLUENCE OF POWER FLUCTUATION ON POWER TRANSFORMERS ABDELKADER ABDELMOUMENE & HAMID BENTARZI Signals and Systems Laboratory, IGEE, Boumerdes University, ALGERIA ABSTRACT The study of the transformer in disturbed working mode and the identification of these disturbances and their origins have a particular importance for the choice and the dimensioning of the transformer; and even for the optimization of the exploitation of the electrical energy placed at the disposal of the consumer. The aim of this paper is to study the behavior of the power transformers following brutal load variations by simulating the different electric parameters of the transformer during the increase or the reduction in power required by the receivers. This study permit to identify and analyze the phenomena accompanying the change of operating condition in order to be considered in the selection of transformers characteristics in the event that these maneuvers will likely happen. KEY WORDS: Simulation, Power Transformer, Disturbed Mode, Loads Variation. INTRODUCTION In our modern world we use more and more technology in our everyday life, to the point where we have become completely dependent on electric power, both in our personal life and for our commercial and industrial activities. The electric power required by consumers varies with time due to various factors: 1. Climate: seasons sucsusion, presence or absence of sunlight in the day .... 2. Sociological: weekly or annual vacancy .... 3. Cultural: with television shows in the evening (football matchs, special event .... In July 1969, landing a man on the moon during the night, triggered in Europe a high demand of electrical power in a less time. 4. Economics: - in long-term industrial development, recession. - in short-term startup and shutdown of industries, and the connection \disconnection of electrical machines (motors, pumps ....). International Journal of Industrial Engineering & Technology (IJIET) ISSN 2277-4769 Vol.2, Issue 2 Sep 2012 31-37 © TJPRC Pvt. Ltd.,