Citation: Korpikiewicz, J.;
Mohamed-Seghir, M. Static Analysis
and Optimization of Voltage and
Reactive Power Regulation Systems
in the HV/MV Substation with
Electronic Transformer Tap-Changers.
Energies 2022, 15, 4773. https://
doi.org/10.3390/en15134773
Academic Editors: Luis
Hernández-Callejo, Sergio
Nesmachnow and Sara Gallardo
Saavedra
Received: 23 May 2022
Accepted: 24 June 2022
Published: 29 June 2022
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Article
Static Analysis and Optimization of Voltage and Reactive
Power Regulation Systems in the HV/MV Substation with
Electronic Transformer Tap-Changers
Jarosław Korpikiewicz * and Mostefa Mohamed-Seghir
Departamet of Ship Automation, Faculty of Electrical Engineering, Gdynia Maritime University,
81-225 Gdynia, Poland; m.mohamed-seghir@we.umg.edu.pl
* Correspondence: j.korpikiewicz@we.umg.edu.pl
Abstract:
The quality of electricity is a very important indicator. The durability and reliable op-
eration of all connected devices depend on the quality of the network voltage. Rapid changes in
loads, changes in network connections and the presence of uncontrolled energy sources require the
development of new voltage regulation systems. This requires voltage regulation systems capable
of responding quickly to sudden voltage changes. In substations with control transformers, it is
possible thanks to the use of semiconductor tap changers. Moreover, voltage regulation and reactive
power compensation systems should be built as one system. This is due to the close dependence
of voltage and reactive power in the network node. Therefore, it was proposed to use artificial
intelligence methods to build a new voltage regulation and reactive power compensation system
using all measurement voltages of network nodes. In the first stage of the research, active and
reactive powers, as well as the voltage of the reference node, were selected for 6420 periods of the
mains voltage. The simulation results were compared for the classic voltage regulation system with
semiconductor tap changers and the evolution algorithm based on voltage measurements from the
entire MV network. A significant improvement in the quality of voltage regulation with the use of an
evolutionary algorithm was demonstrated. Then, a second set of input data with increased values
of reactive power was generated. The results of the evolutionary algorithm after the application of
the classic, independent reactive power compensation system and two-criteria optimization were
compared. It has been shown that only the two-criteria optimization algorithm keeps both |tg
ϕ
|
within the acceptable range and the quality of voltage regulation is the best. The article compares
different working algorithms for semiconductor tap changers.
Keywords:
power system; voltage control; control tap-changer; evolution algorithm; multi-
criteria optimization
1. Introduction
The currently operated voltage regulation systems in HV/MV stations use only the
transformer voltage on the MV side. The analysis of voltage regulation systems using
electromechanical tap-changers of the transformer is presented in [
1
,
2
]. The design of a
traditional tap-changer is shown in Figure 1a. The view of the power transformer with the
on-load tap-changer is shown in Figure 1b.
Measurements of electrical quantities in MV networks (smart grids) are more often
available. There are works on the use of semiconductor tap changers for voltage regulation
in HV, MV and LV networks [
3
–
12
]. The differences between the electromechanical and
semiconductor control algorithms are presented, among others, in [
13
,
14
]. There are
applications of power semiconductors in high-voltage and high-power circuits, e.g., [
15
].
There is a need to develop optimally integrated voltage regulation and reactive power
compensation [
16
–
20
]. It is indispensable to use artificial intelligence methods to design
voltage regulation and reactive power compensation systems [21,22].
Energies 2022, 15, 4773. https://doi.org/10.3390/en15134773 https://www.mdpi.com/journal/energies
