Here we are in a new year, which will hopefully bring
new advancements to the journal, but most certainly it
will also impose additional challenges before us. I will keep
it quiet for now and leave some important announcements for
the end of year. However, you will notice that we redesigned
the front page of the hard-copy and also registered an e-ISSN
for better coverage of the journal’s online content.
In this volume, we bring four papers that report original
research results in the field of sensor modeling, antenna design,
and power electronics.
In the first paper, entitled “Mathematical Model and Practi-
cal Implementation of Transformer Oil Humidity Sensor,” the
authors, V. F. Hraniak, V. A. Matviychuk, and I. M. Kupchuk,
developed a mathematical model for transformer oil humidity
sensor. They also proved experimentally that the total relative
error, which is introduced by the model, does not exceed 2%.
The second study, entitled “Designing and Implementing
a Microstrip Antenna on LoRa Frequency for Smart Me-
ter Communication,” by P. Wounchoum, A. Kongsavat, and
C. Karupongsiri, describes a design of micro-strip antenna
(MSA), which is used afterwards for developing a new path
loss model for LoRaWAN infrastructure in urban areas. The
obtained results show that proposed MSA is comparable to
commercial solutions in a 2.2 km range, with packet delivery
ratio reaching 52.93%.
The third paper, “Design and Simulation of a Power System
Composed of Grid-Tied Five-Level Inverter with LCL Filter,”
authored by O. Elamri, A. Oukassi, A. E. T. Maamar, and
L. El Bahir, presents the analysis, design, and simulation of
a power system composed of grid-tied single-phase five-level
inverter with an LCL filter. The authors provide theoretical
analysis of the proposed design, which is further verified using
simulations in MATLAB/Simulink environment. The obtained
results indicate that the total harmonic distortion of grid-
current is less than 0.2%, which is in line with the international
standards.
Finally, the paper “Direct Torque Control of Induction
Motor with Stator Flux Estimation Based on an Improved
Voltage Model,” by A. Belbali and S. Makhloufi, proposed a
solution for improving the stator flux estimator by introducing
a fractional order integrator to estimate the flux at low-speed.
The proposed solution does not require additional hardware, it
is not computationally intensive, and provides accurate results.
The authors demonstrated its operation on dSPACE 1104
platform.
I thank the authors for their contribution to this issue of
the journal and to all the reviewers who participated in the
editorial process by providing valuable comments in timely
manner to the editors and authors.