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Managing cascade transformers equipped with on-load tap changers in bidirectional power flow environment

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Original languageEnglish
Title of host publication2015 IEEE Eindhoven PowerTech
Number of pages5
Publication statusPublished - 1 Jun 2015
Publication typeA4 Article in a conference publication
EventIEEE Powertech -
Duration: 1 Jan 1900 → …


ConferenceIEEE Powertech
Period1/01/00 → …


Existing voltage control schemes of cascade on-load tap changers (OLTCs) have been developed considering unidirectional power flow. However, in recent years, integration of distributed generation such as solar and wind power to the grid has created possibility for bidirectional power flow resulting in inefficiency of previous voltage control methods of cascade OLTCs. In this paper, an effective method for managing cascade OLTCs in bidirectional power flow environment is presented. Tracking the active and reactive power changes in both MV and LV networks, the developed method is able to detect the cause of voltage variation i.e. MV or LV network. Accordingly, it enables the system operator to order tap actions at accurate voltage level which decreases unnecessary tap actions and improves the voltage quality at costumer points. The proposed voltage control method is tested in different network scenarios.


  • distributed power generation, load flow control, on load tap changers, power grids, voltage control, LV networks, MV networks, bidirectional power flow environment, cascade on-load tap changers, cascade transformers, distributed generation, power grid, reactive power, solar power, voltage quality, voltage variation, wind power, Automatic voltage control, Delay effects, Load flow, Reactive power, Relays, Voltage fluctuations, bidirectional power flow, origin of voltage violation

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