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ANN BASED CONTROL PATTERNS ESTIMATOR FOR UPFC USED IN POWER FLOW PROBLEM 1 1
G. Tulasi Ram Das
Department of Electrical and Electronics Engineering, Chaitanya Bharathi Institute of Technology, Hyderabad, India. 2 Department of Electrical and Electronics Engineering, J.N.T.U. College of Engineering Hyderabad, India. Email: email@example.com
ABSTRACT The continuous growth in the demand for electric power necessitates the flexibility of operation in power system. Of different power electronics-based Flexible AC Transmission System (FACTS) devices, which enhance the power transmission capabilities, Unified Power Flow Controller (UPFC) provides an emerging and promising solution for the power flow problems in the system, as it simultaneously and/or selectively controls the transmission parameters. In this context, the paper proposes the power flow control in a simple system by injecting the series compensating voltage, which is an important function of UPFC. For this purpose, ANN controller based UPFC is used. Control patterns are generated for obtaining the adjustable series voltage from the second converter that, in turn, controls the power flow in the system. With the proposed model, by varying control coefficient the series injected voltage can be adjusted. MATLAB Simulation is used to test the proposed model. The control horizon is identified and presented for various values of existing active and reactive powers. Key words: FACTS, UPFC, ANN, Power Flow Control.
1. INTRODUCTION The UPFC is conceptually a Synchronous Voltage Source (SVS) [1, 2] which generates the adjustable voltage on the ac side. The voltage source exchanges both active power and reactive power with the transmission system. The UPFC consists of two-voltage source converters, one in series and one in shunt in a transmission line. Both using switching...