Cost Optimal Design of a Power Inductor by Sequential Gradient Search

  • Raju BasakEmail author
  • Arabinda Das
  • Amarnath Sanyal
Case Study


Power inductors are used for compensating VAR generated by long EHV transmission lines and in electronic circuits. For the EHV-lines, the rating of the inductor is decided upon by techno-economic considerations on the basis of the line-susceptance. It is a high voltage high current device, absorbing little active power and large reactive power. The cost is quite high- hence the design should be made cost-optimally. The 3-phase power inductor is similar in construction to a 3-phase core-type transformer with the exception that it has only one winding per phase and each limb is provided with an air-gap, the length of which is decided upon by the inductance required. In this paper, a design methodology based on sequential gradient search technique and the corresponding algorithm leading to cost-optimal design of a 3-phase EHV power inductor has been presented. The case-study has been made on a 220 kV long line of NHPC running from Chukha HPS to Birpara of Coochbihar.


EHV long line VAR generation Power inductor Cost-optimal design Sequential gradient search 


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Copyright information

© The Institution of Engineers (India) 2018

Authors and Affiliations

  1. 1.Geological Survey of IndiaKolkataIndia
  2. 2.Jadavpur UniversityKolkataIndia
  3. 3.Academy of TechnologyHooghlyIndia

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