Research Article Open Access

Power-Voltage Characteristics of Power System with the Long Transmission Line

Prechanon Kumkratug1
  • 1 Department of Electrical Engineering, Faculty of Engineering at Si Racha, Kasetsart University, 199 M.6, Tungsukhla, Si Racha, Chonburi, 20230, Thailand


Problem statement: Power- Voltage curve provides very important information for voltage stability analysis. The exact long transmission line model consists of the resistance and the reactance. The resistance causes in the active line loss. It is not easy task to achieve the power-voltage curve characteristics of power system with the exact long line model. Approach: This study applies the concept of the Newton-Raphson method to iteratively solve the nonlinear power flow equations. The Power-Voltage (P-V) curve characteristic of the system without line loss and with line loss are plotted and compared on various cases. Results: It is found from the study that the resistance of the line obviously provides the negative effects on the voltage stability. The line loss causes in the decrement of the critical point. In addition, it is found that the leading power factor can increase the critical point of P-V curve. Conclusion: The exact long line model should be considered for voltage stability analysis of the system with the long transmission line.

American Journal of Applied Sciences
Volume 9 No. 10, 2012, 1534-1537


Submitted On: 3 March 2012 Published On: 10 August 2012

How to Cite: Kumkratug, P. (2012). Power-Voltage Characteristics of Power System with the Long Transmission Line. American Journal of Applied Sciences, 9(10), 1534-1537.

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  • Voltage stability
  • voltage collapse
  • critical voltage
  • critical power
  • power-voltage curve
  • newton-raphson
  • reactive power
  • active power