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ISSN E 2409-2770
ISSN P 2521-2419

Design of Hybrid Electromechanical Switch for Automatic Voltage Control of on Load Tap Changer Transformer

Uzair Khan and Dr. Abdul Basit

Vol. 10, Issue 03 PP. 22-29, March 2023


Keywords: Hybrid switch, On-load tap changer, Bi-directional switch, No-load switch, Auto-transformer

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On Load tap changer OLTC transformer having electromechanical hybrid switch, is used to regulate voltage level by changing the taps without arcing which cause increase or decrease in voltage level in a very efficient and coherent manner depending upon the requirement of the system. Mostly mechanical type of On Load tap Changer is widely used for control voltage in distributed networks. Mechanical On Load Tap Changer has some disadvantages during tap changing process like causing arc, slow switching, high malfunction rate and require manpower. In mechanical switches wear and tear occurs due to tap changing due to the arcing phenomenon. Besides these drawbacks, there are also some advantages of mechanical OLTC such as low on-steady losses and high overload capacity. Due to fluctuations in voltage level of smart grid a hybrid power electronic assisted mechanical On Load Tap Changer transformer is designed. In this research paper a hybrid Switch is proposed using the advantages of mechanical as well as electronic bidirectional switches for automatic tap changing of OLTC transformer. The electronic OLTC uses semiconductor namely IGBT as a bidirectional switch. By using electromechanical switch the taps changing process will be arc less and there will be low On-state losses and high over load capacity. This will provide automatic, arc free tap change and long lifetime.

  1. Uzair Khan,, Center for Advanced Studies in Energy (CAS-E), Department of Electrical Energy System, University of Engineering and Technology Peshawar, Pakistan.
  2. Abdul Basit,, Center for Advanced Studies in Energy (CAS-E), Department of Electrical Energy System, University of Engineering and Technology Peshawar, Pakistan.

Uzair Khan Dr. Abdul Basit Design of Hybrid Electromechanical Switch for Automatic Voltage Control of on Lo Vol. 10 Issue 03 PP. 22-28 March 2023.

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