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Day similarity metric model for short-term load forecasting supported by PSO and artificial neural network

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This paper proposes a new model for optimal similar days selection and its use in short-term load forecasting based on artificial neural network. Proposed day similarity metric model is based on the multi-filtering process and introduces a few novelties: (1) introduction of pre-history of similar days in a selection process; (2) extension of forecasting factors: load inertia, daylight duration and load profiles; (3) open model with possibility to add additional contribution factors; (4) particle swarm optimization is applied for calculation of the impact of different contributing factors. This approach results in optimal similar days selection even in a case where it is not obvious in advance which factors are the most relevant. Finally, the artificial neural network is used as a basic procedure for the short-term load forecast. The proposed model has been tested in the transmission system utility in Serbia, and the results are presented.
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Vol.:(0123456789)
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Electrical Engineering (2021) 103:2973–2988
https://doi.org/10.1007/s00202-021-01286-6
ORIGINAL PAPER
Day similarity metric model forshort‑term load forecasting supported
byPSO andartificial neural network
ZoranJanković1· AleksandarSelakov1 · DuškoBekut1· MarijaĐorđević2
Received: 7 September 2019 / Accepted: 1 April 2021 / Published online: 16 April 2021
© The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2021
Abstract
This paper proposes a new model for optimal similar days selection and its use in short-term load forecasting based on
artificial neural network. Proposed day similarity metric model is based on the multi-filtering process and introduces a few
novelties: (1) introduction of pre-history of similar days in a selection process; (2) extension of forecasting factors: load
inertia, daylight duration and load profiles; (3) open model with possibility to add additional contribution factors; (4) particle
swarm optimization is applied for calculation of the impact of different contributing factors. This approach results in opti-
mal similar days selection even in a case where it is not obvious in advance which factors are the most relevant. Finally, the
artificial neural network is used as a basic procedure for the short-term load forecast. The proposed model has been tested
in the transmission system utility in Serbia, and the results are presented.
Keywords Artificial neural network· Particle swarm optimization· Short-term load forecast· Similar days
Abbreviations
STLF Short-term load forecasting
DSMM Day similarity metric model
PSO Particle swarm optimization
ANN Artificial neural network
GA Genetic algorithm
Sc Similarity coefficient
pc Participation coefficient
wf Weighting coefficient
FA Forecasted array
HA Historical array
nfw Number of weather factors
dd Daylight duration
HA Historical array
FA Forecasted array
in Inertia
ddwf Day decreasing weighting coefficient
avgP Average load
d Day
σ Standard load deviation
Cσ Load deviation contribution
Lσ Selected border value
MAPE Mean absolute percentage error
Pf Forecasted load
Pr Realized load
1 Introduction
In modern electrical utilities, short-term load forecasting is
essential for reliable power system operations, and it signifi-
cantly affects power system economics. Forecasting electri-
cal load a day ahead, usually referred to as short-term load
forecasting (STLF), is one of the critical needs for electrical
utility and transmission system operators to make decisions
regarding purchasing and selling electric power/energy,
balancing of the system, maintenance, load switching and
maintenance planning.
A typical STLF process relies on the forecasted weather
information and takes weather and load history as the inputs
to the modeling process. After the estimation of the param-
eters, the model and weather forecast are extrapolated to
generate the final forecast [1].
Among many STLF approaches, one of the critical steps
in the STLF process is similar days selection [226, 39, 40].
* Aleksandar Selakov
aselakov@uns.ac.rs
1 University ofNovi Sad, Faculty ofTechnical Sciences,
Department ofPower, Electronic andTelecommunication
Engineering, Trg Dositeja Obradovića 6, 21000NoviSad,
Serbia
2 Serbian Transmission System Company, 11 Kneza Miloša,
11000Belgrade, Serbia
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