Razgar Ebrahimy

Dr. Razgar Ebrahimy

Department of Applied Mathematics and Computer Science, Technical University of Denmark, 2800 Kgs., Lyngby, Denmark

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 May 2022 in Renewable and Sustainable Energy Reviews
Verified
Journal Article
Open access
Francesco D’EttorreFrancesco D’Ettorre
Francesco D’Ettorre
MBMohsen Banaei
Mohsen Banaei
Razgar EbrahimyRazgar Ebrahimy
Razgar Ebrahimy
SKSeyyed Ali Pourmousavi Kani
Seyyed Ali Pourmousavi Kani
EBEmma Margareta Viktoria Blomgren
Emma Margareta Viktoria Blomgren
HMHenrik Madsen
Henrik Madsen

3 June 2020 in Energies
Verified
Journal Article
Open access
PDF file
KLKenneth Leerbeck
Kenneth Leerbeck
PBPeder Bacher
Peder Bacher
RJRune Grønborg Junker
Rune Grønborg Junker
ATAnna Tveit
Anna Tveit
OCOlivier Corradi
Olivier Corradi
Razgar EbrahimyRazgar Ebrahimy
Razgar Ebrahimy
An optimized heat pump control for building heating was developed for minimizing CO 2 emissions from related electrical power generation. The control is using weather and CO 2 emission forecasts as inputs to a Model Predictive Control (MPC)—a multivariate control algorithm using a dynamic process model, constraints and a cost function to be minimized. In a simulation study, the control was applied using weather and power grid conditions during a full-year period in 2017–2018 for the power bidding zone DK2 (East, Denmark). Two scenarios were studied; one with a family house and one with an office building. The buildings were dimensioned based on standards and building codes/regulations. The main results are measured as the CO 2 emission savings relative to a classical thermostatic control. Note that this only measures the gain achieved using the MPC control, that is, the energy flexibility, not the absolute savings. The results show that around 16% of savings could have been achieved during the period in well-insulated new buildings with floor heating. Further, a sensitivity analysis was carried out to evaluate the effect of various building properties, for example, level of insulation and thermal capacity. Danish building codes from 1977 and forward were used as benchmarks for insulation levels. It was shown that both insulation and thermal mass influence the achievable flexibility savings, especially for floor heating. Buildings that comply with building codes later than 1979 could provide flexibility emission savings of around 10%, while buildings that comply with earlier codes provided savings in the range of 0–5% depending on the heating system and thermal mass.

24 September 2022 in International Journal of Electrical Power & Energy Systems
Verified
Journal Article
Open access
MBMohsen Banaei
Mohsen Banaei
FDFrancesco D’eTtorre
Francesco D’eTtorre
Razgar EbrahimyRazgar Ebrahimy
Razgar Ebrahimy
SKSeyyed Ali Pourmousavi Kani
Seyyed Ali Pourmousavi Kani
EBEmma Margareta Viktoria Blomgren
Emma Margareta Viktoria Blomgren
HMHenrik Madsen
Henrik Madsen

19 October 2024
Verified
Book Chapter
Closed access
PDF file
HMHenrik Madsen
Henrik Madsen
STSeyed Shahabaldin Tohidi
Seyed Shahabaldin Tohidi
Razgar EbrahimyRazgar Ebrahimy
Razgar Ebrahimy
MBMohsen Banaei
Mohsen Banaei
TRTobias K. S. Ritschel
Tobias K. S. Ritschel
NMNariman Mahdavi
Nariman Mahdavi

27 May 2023 in Energies
Verified
Journal Article
Open access
PDF file
EBEmma Margareta Viktoria Blomgren
Emma Margareta Viktoria Blomgren
MBMohsen Banaei
Mohsen Banaei
Razgar EbrahimyRazgar Ebrahimy
Razgar Ebrahimy
OSOlof Samuelsson
Olof Samuelsson
Francesco D’EttorreFrancesco D’Ettorre
Francesco D’Ettorre
HMHenrik Madsen
Henrik Madsen
Increasing levels of distributed generation (DG), as well as changes in electricity consumption behavior, are reshaping power distribution systems. These changes might place particular stress on the secondary low-voltage (LV) distribution systems not originally designed for bi-directional power flows. Voltage violations, reverse power flow, and congestion are the main arising concerns for distribution system operators (DSOs), while observability in these grids is typically nonexistent or very low. The present paper addresses this issue by developing a method for nodal voltage estimation in unbalanced radial LV grids (at 0.4 kV). The workflow of the proposed method combines a data-driven grey-box modeling approach with generalized additive models (GAMs). Furthermore, the proposed method relies on experimental data from a real-world LV grid in Denmark and uses data input from only one measuring device per feeder. Predictions are evaluated by using a test data set of 31 days, which is more than twice the size of the training data set of 13 days. The prediction results show high accuracy at root mean squared errors (RMSEs) of 0.002–0.0004 p.u. The method also requires a short computation time (14 s for the first stage and 2 s for the second stage) that meets requirements for the practical, real-time monitoring of DSO grids.

28 December 2023 in International Journal of Electrical Power & Energy Systems
Verified
Journal Article
Open access
MBMohsen Banaei
Mohsen Banaei
FDFrancesco D’eTtorre
Francesco D’eTtorre
Razgar EbrahimyRazgar Ebrahimy
Razgar Ebrahimy
MAMads R. Almassalkhi
Mads R. Almassalkhi
HMHenrik Madsen
Henrik Madsen