Advanced Load Flow Analysis for Unbalanced Radial Distribution System Incorporating Weather Conditions

  • Surender SinghEmail author
  • V. R. Singh
  • R. Ranjan
  • S. Swapnil
Original Contribution


In this paper, an advanced load flow algorithm is prepared for an unbalanced radial distribution system incorporating weather conditions. To determine the exact power losses and to enhance the efficiency of unbalanced load flow solutions, the effect of ambient conditions of branch resistance is considered. This attempts to incorporate the weather conditions while solving unbalanced radial distribution systems. The proposed algorithm has been tested on 25-bus and 19-bus unbalanced RDS. The results are compared with conventional load flow analysis of unbalanced radial distribution systems, and a noticeable change in the power loss, resistance and node voltages was observed when impedances are considered as a fixed parameter than weather sensitive.


Advanced unbalanced load flow analysis (AULFA) Conventional unbalanced load flow analysis (CULFA) Unbalanced radial distribution system (URDS) 



  1. 1.
    J. Nanda, M.S. Srinivas, M. Shma, S.S. Dev, L. L. Lai, New findings on radial distribution system load flow algorithms, in IEEE Conference (2000), pp. 1157–1161Google Scholar
  2. 2.
    B. Venkatesh, R. Ranjan, Data structure for radial distribution system load flow analysis, in IEE Proceedings -Gener. Trans. Distrib. vol 150. No 1. (January 2003)Google Scholar
  3. 3.
    T. Thakur, J. Dhiman, A new approach to load flow solutions for radial distribution system, in IEEE Conference (2006)Google Scholar
  4. 4.
    G.W. Chang, S.Y. Chu, H.L. Wang, An improved backward/forward sweep load flow algorithm for radial distribution systems. IEEE Trans. Power Syst. 22(2), 882–884 (2007)CrossRefGoogle Scholar
  5. 5.
    S.K. Goswami, S.K. Basu, Direct solution of distribution systems. IEEE Proc. Part C 188(1), 78–88 (1999)Google Scholar
  6. 6.
    D. Thukaram, H.M.W. Banda, J. Jerome, A robust three phase power flow algorithm for radial distribution systems. J. Electr. Power Syst. Res. 50(3), 227–236 (1999)CrossRefGoogle Scholar
  7. 7.
    P.U. Reddy, S. Sivanagaraju, P. Sangameswararaju, Power flow analysis of three phase unbalance radial distribution system. Int. J. Adv. Eng. Technol. 3(1), 514–524 (2012)Google Scholar
  8. 8.
    V.V.S.N. Murtya, A. Kumarb, Capacitor allocation in unbalanced distribution system under unbalances and loading conditions, in 4th International Conference on Advances in Energy Research 2013, ICAER 2013, Energy Procedia 54 (2014) 47–74Google Scholar
  9. 9.
    M. Sedighizadeh, R. Bakhtiary, Optimal multi-objective reconfiguration and capacitor placement of distribution systems with hybrid big bang–big crunch algorithm in the fuzzy framework. Ain Shams Eng. J. 7, 113–129 (2016)CrossRefGoogle Scholar
  10. 10.
    U. Ghatak, V. Mukherjee, A fast and efficient load flow technique for unbalanced distribution system. Electr. Power Energy Syst. 84, 99–110 (2017)CrossRefGoogle Scholar
  11. 11.
    R.A. Maraio, S.D. Foss, Effect of variability in weather conditions on conductor temperature and the dynamic rating of transmission lines. IEEE Trans. Power Deliv. 3(4), 1832–1841 (1988)CrossRefGoogle Scholar
  12. 12.
    H. Banakar, N. Alguacil, F.D. Aliana, Electrothermal coordination part I: theory and implementation schemes. IEEE Trans. Power Syst. 20(2), 798–805 (2005)CrossRefGoogle Scholar
  13. 13.
    N. Alguacil, M.H. Banakar, F.D. Galiana, Electrothermal coordination part II: case studies. IEEE Trans. Power Syst. 20(4), 1738–1745 (2005)CrossRefGoogle Scholar
  14. 14.
    M. Bockarjova, G. Andersson, Transmission line conductor temperature impact on state estimation accuracy, in Power Tech, 2007 IEEE Lausanne, SwitzerlandGoogle Scholar
  15. 15.
    S. Frank, J. Sexauer, S. Mohagheghi, Temperature dependent power flow. IEEE Trans. Power Syst. 28, 4007–4018 (2013)CrossRefGoogle Scholar
  16. 16.
    J.R. Santos, A.G. Exposito, F.P. Sanchez, Assessment of conductor thermal models for grid studies. IET Gener. Transm. Distrib. 1(1), 155–161 (2007)CrossRefGoogle Scholar
  17. 17.
    IEEE Standard for Calculating the Current-Temperature of Bare Overhead Conductors, IEEE Std. 738, 2006Google Scholar
  18. 18.
    S. Frank, J. Sexauer, S. Mohagheghi, Temperature dependent power flow. IEEE Trans. Power Syst. 28, 4007–4018 (2013)CrossRefGoogle Scholar
  19. 19.
    R. Ranjan, B. Venkatesh, A. Chaturvedi, D. Das, Power flow solution of three-phase unbalanced radial distribution network, Electric Power Components and Systems, 421–433, 24th June 2010Google Scholar
  20. 20.
    M. Kumari, R. Ranjan, V.R. Singh, S. Swapnil, Weather sensitive load flow analysis of radial distribution system. WSEAS Trans. Power Syst. 13, 78–88 (2018)Google Scholar
  21. 21.
    M. Kumari, V.R. Singh, R. Ranjan, Optimal selection of conductor in RDS considering weather condition, in 2018 International Conference on Computing, Power and Communication Technologies (GUCON) (2018), pp 647–651Google Scholar
  22. 22.
    Q. Gao, Z. Wei, G. Sun, Y. Sun, H. Zang, Temperature-dependent optimal power flow based on simplified interior point method, in 5th International Conference on Electric Utility Deregulation and Restructuring and Power Technologies, nov. 26–29 (2015), pp 765–769Google Scholar
  23. 23.
    M.M. Legha, H. Javaheri, M.M. Legha, Optimal conductor selection in radial distribution systems for productivity improvement using genetic algorithm, Iraq J. Electr. Electron. Eng. Vol.9 No.1, 2013Google Scholar
  24. 24.
    J.B.V. Subrahmanyam, Planning and Optimization of Unbalanced Distribution Systems, Jawaharlal Nehru Technological University, (August 2011)Google Scholar
  25. 25.
    Ganesh Vulasala, Sivanagaraju Sirgiri, Ramana Thirucleedula, Genetic algorithm based voltage regulator placement in unbalanced radial distribution system. Acta Electrotech. 50(4), 253–259 (2009)Google Scholar

Copyright information

© The Institution of Engineers (India) 2019

Authors and Affiliations

  • Surender Singh
    • 1
    Email author
  • V. R. Singh
    • 2
  • R. Ranjan
    • 3
  • S. Swapnil
    • 4
  1. 1.Department of Electrical Engineering, UIETMDURohtakIndia
  2. 2.Department of Electrical Engineering, PDMCEMDUBahadurgarhIndia
  3. 3.Himgiri Zee UniversityDehradunIndia
  4. 4.Department of Computer and Information Science and EngineeringUniversity of FloridaGainesvilleUSA

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