Generator reactive power pricing for practical utility system using power flow tracing method


  • Danalakshmi D
  • Kannan S
  • Gnanadass R





Ancillary Services, Capability Curve, Opportunity Cost, Power Flow Tracing, Reactive Power Pricing.


The shift from regulated to restructured power system results in an increased competition among the electricity market. In restructured power system, the separation of transmission services from generation and distribution makes it necessary to find the contribution of power from individual generator to individual load. The power flow tracing method is used to obtain the generator power output to a particular load. The reactive power has to be maintained in order to sustain the voltage level throughout the system for reliable and secure operation. Hence the reactive power cost allocation has become imperative in the power system. In this paper, the tracing method is integrated with the optimal reactive power dispatch problem to trace the generator minimal reactive power for sustaining the real power transaction and enhancing the system security by meeting the demand. The Differential Evolution is used for optimal reactive power dispatch. The cost allocation to the generators for the reactive power service based on the opportunity cost method is obtained for 62 Bus Indian Utility Systems.


[1] Shahidehpour M, Yamin H, and Li Z. Market Operations in Electric Power Systems. Wiley-Interscience, John Wiley & Sons, Inc, 2002.

[2] Federal Energy Regulatory Commission et al. Principles for efficient and reliable reactive power supply and consumption. FERC Staff Reports, Docket No. AD05-1- 000, pages 161–162, 2005.

[3] John W. L and Jian F. Cost analysis of reactive power support. Power Systems, IEEE Transactions on, 14(3):890–898, 1999.

[4] Garc´ıa-Rom´an JI. Analysis and decomposition of the electricity market active and reactive power spot price under centralized management. International Journal of Electrical Power & Energy Systems, 43(1):1179–1184, 2012.

[5] Javad S, Hassan G, and Saeed A. Reactive power procurement model in electricity markets based on normalized effective reactive power reserve. International Transactions on Electrical Energy Systems, 24(6):858–874, 2014.

[6] Mala D and Swapan K G. Reactive power cost allocation by power tracing based method. Energy Conversion and Management, 64:43–51, 2012.

[7] Mala D and Swapan K G. Optimal reactive power procurement with voltage stability consideration in deregulated power system. IEEE transactions on power systems, 29(5):2078–2086, 2014.

[8] Kadir A and Volkan Yamac¸li. Optimal reactive-power dispatch using differential search algorithm. Electrical Engineering, pages 1–13, 2016.

[9] Susithra M and Gnanadass R. Power flow tracing based reactive power ancillary service (as) in restructured power market. World Academy of Science, Engineering and Technology, International Journal of Electrical, Computer, Energetic, Electronic and Communication Engineering, 8(10):1603–1610, 2014.

[10] Ramesh S, Kannan S, and Baskar S. An improved generalized differential evolution algorithm for multi-objective reactive power dispatch. Engineering Optimization, 44(4):391–405, 2012.

[11] Bialek J. Tracing the flow of electricity. IEE Proceedings-Generation, Transmission and Distribution, 143(4):313–320, 1996.

[12] Hasanpour S, Ghazi R, and Javidi MH. A new approach for cost allocation and reactive power pricing in a deregulated environment. Electrical Engineering, 91(1):27–34, 2009.

[13] Gnanadass R. Optimal, power dispatch and pricing for deregulated power industry. PhD thesis, Pondicherry University, India, March 2005.

[14] Planning Wing of Tamil Nadu Electricity Board. Tamil nadu electricity board statistics at a glance: 1999-2000. Technical report, Chennai, India.

View Full Article: