Abstract: This paper presents an automatic reactive power control of autonomous winddiesel
hybrid power systems (AWDHPS) by artificial neural network (ANN)
controller tuned static var compensator (SVC). The real time assessment of
such control was carried out using dSPACE R & D controller board. The
proposed ANN controller was supported by multilayer perceptron artificial
neural network (MPANN). The weights of proposed MPANN were restructured
by intensive learning process. The back propagation equations were used
to dynamically regulate the weights of proposed MPANN controller. Three
models ofAWDHPSwere considered in the study. The disturbance parameters
in the models were the change in reactive power of the load (ΔQL), the change
in mechanical power input of the single induction generator (ΔPIW) and
the change in mechanical power input of two induction generators (ΔPIW1,
ΔPIW2) respectively. The parameters were dynamically varied in control
desk of dSPACE Software with DS1104 R & D controller board mounted
in personal computer under real time environment. The static and dynamic
response curves were depicted. The reactive power deviations realized using
the proposed MPANN controller was found to be very less compared to the
deviations shown in ANN controller present in literature. The time domain specifications ofSVCobtained by the proposedMPANNcontroller were better
than a Proportional plus Integral (PI) controller.
Keywords: dSPACE, Neural Networks, Reactive Power Control, Wind-
Diesel System.
Support Vector Machine Based Classification of Current Transformer Saturation Phenomenon doi: https://doi.org/10.13052/jge1904-4720.7122
N. G. Chothani1, D. D. Patel2 and K. D. Mistry2
1Electrical Department, A. D. Patel Institute of Technology, New Vallabh
Vidhyanagar, Gujarat, India
2Electrical Department, Sardar Vallabhbhai National Institute of Technology,
Surat, Gujarat, India
Abstract: [+] | Download File [ 1478KB ] | Read Article Online
Abstract: During out of zone fault, Current Transformer (CT) saturation leads maloperation
in unit type protective schemes. Detection and classification of
saturation condition ofCTis still a challenging issue. Thus, it is most important
to correctly categorize CT saturation condition to increase reliability and
stability of protective schemes. The proposed scheme utilizes transmission
line CT secondary post fault current signals (sliding window) as an input
to SVM. In order to achieve the most optimized classifier, Gaussian Radial
Basis Function (RBF) has been used for training of SVM. Feasibility of
the proposed scheme has been tested by modelling a part of 220 kV power
systems in PSCAD/EMTDC software package. The algorithm is executed
in MATLAB software. More than 720 unsaturated and 3600 saturated cases
with varying burden resistance, remnant flux, DC component of current, noise
penetration to current signal and fault inception angle have been generated and
used for validation of the proposed scheme. The proposed scheme effectively
discriminates between CTsaturated and unsaturated conditions with very high
classification accuracy more than 99% for different parameter variations.
Keywords: CT Saturation, Burden Resistance, Remnant Flux, Support
Vector Machine (SVM), Power System, Fault Condition.
Abstract: This paper proposes the optimization of renewable energy resources (RERs) in
the hybrid energy systems in a sustainable hybrid energy system. The behavior
of renewable energy is uncertain and it is difficult for static optimization
methods to optimize the uncertain non-stationary distributed energy resources
in the hybrid system. A multi-objective based on the stochastic technique for
optimizing total system losses and operating cost is formulated for the hybrid
energy system. The proposed objective function aims to minimize the system
losses and the total operating cost of RERs in different locations of the grid.
In this paper, a next generation of grid connected RERs and load demand
is proposed by considering the variability and uncertainty. Here, a robust
stochastic approach is proposed by using the various probability distribution
functions to represent the statistics of RERs. The simulation results of this
paper handle the system operations under uncertainty. The proposed approach
is tested on IEEE 37 node distribution system. The simulation results show
the effectiveness of the proposed optimization approach in the hybrid energy
system.
Keywords: Renewable energy, Optimization, Hybrid energy systems,
Probability distribution, Uncertainty.
Electric Load Forecasts by Metaheuristic Based Back Propagation Approach doi: https://doi.org/10.13052/jge1904-4720.7124
Papia Ray1, Sabha Raj Arya2 and Shobhit Nandkeolyar1
1Department of Electrical Engineering, Veer Surendra Sai University
of Technology, Burla, Odisha, India
2Department of Electrical Engineering, Sardar Vallabhbhai National Institute
of Technology, Surat-395007, India
Abstract: [+] | Download File [ 1168KB ] | Read Article Online
Abstract: The prediction of system load demands a day ahead or a week ahead is
called Short Term Load Forecasting. Artificial Neural Network based STLF
model has gained significance because of transparency in its modelling,
simplicity of execution, and superiority of its performance. The neural model
consists of weights whose optimal values are found out by means of different
optimization techniques. In this paper, Artificial Neural Network trained by
different methods like Back Propagation, Genetic Algorithm, Particle Swarm
Optimization, Cuckoo Search model and Bat algorithm is utilized for load
forecasting.Athorough analysis of the different techniques is carried out here
in order to assess their extent and capability to yield result, by means of
dissimilar models, in altered situations. The simulation results indicate that
Bat Algorithm based Back Propagation model leads to least forecasting error
in comparison to other techniques. However, Cuckoo Search method based
Back Propagation model also gives less error relatively, which is very much
permissible.
Keywords: Short Term Load Forecasting, Metaheuristic, Genetic Algorithm,
Particle Swarm Optimization, Cuckoo Search, Bat Algorithm.
Abstract: In present time, the application of the voltage source inverter (VSI) are rapidly
been increasing. Different designing methods are followed for the construction
of VSI. The purpose of adopting for different techniques of inverter design
is to decrease the harmonic contents from the output waves of VSI. Hence
the comparison of three different voltage source inverters with their different
techniques is discussed in this paper for the purpose of reduction in harmonics.
Total harmonic distortion (THD) analysis of all three VSI has been done.THD
analysis of sine pulse width modulation (SPWM) and third harmonic injection
pulse width modulation (THIPWM) is further discussed in two manners – over
modulation and exact modulation. A unique type of 7 level 5 switch voltage
source multi-level inverter with phase disposition pulse width modulation
(PDPWM) technique is also discussed and its comparison is made with earlier
two techniques. In renewable energy systems, we need to control the power
generation in a very efficient manner. Hence these inverters with low THD
values can be utilized in that field for reduction in losses and increase in
efficiency of the renewable system. Simulation of all three techniques based
VSI is done on MATLAB platform and THD is compared.
Keywords: VSI, PWM, SPWM, THIPWM, PDPWM, MLI, THD.
Abstract: In this research article, the performance metrics (Performance Ratio, Capacity
Utilisation Factor and System efficiency) of Grid connected solar plants
are defined and significance of each metric is discussed thoroughly. The
performance metrics of 120kWp on the rooftop of PG Block and 20kWp
on the rooftop of Library block, which are commissioned in CVR College
of Engineering are calculated and analyzed for a period of one year. In
this research work more emphasise is given to three performance metrics
namely Capacity Utilization Factor (CUF), Performance Ratio (PR) and
System Efficiency (SE). The calculated results of Performance metrics reveal
that performance of both power plants are almost similar to one another in
maximum number of months in an year with slight change in their values
and for few months their values are much deviated from one another. Exact
reasons are investigated for this sort of performance. The calculated values
of Performance Metrics of both these plants are well above the solar industry
standards and can compete with values of Megawatt scale PV plants.
Keywords: Capacity Utilization Factor (CUF), Grid Connected Solar PV
Plant, Performance Metrics, Performance Ratio (PR), System Efficiency (SE),
Point of Common Coupling (PCC).
Abstract: In near future, fuel cell (FC) based power generation system will witness
higher scalability due to merits like reliability, portability and negligible
environmental impact. This paper presents grid integrated fuel cell generator
as micro grid and interacts with modeling and simulation of control
architecture (voltage, active and reactive power) along with vital design
aspect of interface filter. The fuel cell system output is connected to current
controlled voltage source converter (VSC) which controls active and reactive
power. Power balance control theory (PBCT) is used to generate gate
pulses for VSC. Hybrid fuzzy PI controller is used to attain constant DC
link voltage. Simulation of entire system based on fuel cells is undertaken
through MATLAB/Simulink software. PBCT and synchronous reference
frame theory (SRFT) control strategies are also compared for grid connected
FC system.
Keywords: SOFC, Power balance control theory, voltage source converter
(VSC), hybrid FLC, renewable energy sources.
Abstract: Due to the growing demand for energy sets concern for the researchers to
emphasize power generation through non-conventional sources because of
their advantages over conventional source. This leads towards the intense
research work carried out on fuel cells. Fuel cells have the ability of supplying
electricity in the situation where the scope of conventional or other
non-conventional power generating option is difficult to implement. The
other advantages are transportability, flexibility, suitability and environment
friendly operation. The particular advantage of transportability is well utilized
in distributed power applications such as on board power supplies. This paper
focuses on a low power converter energized by a fuel cell. It gives an overview
of modelling of fuel cell and flyback converter with its different topologies
that can be used in sensor application. Here different topologies of flyback
converter are taken into consideration and out of these different topologies,
the highest efficiency topology is chosen to supply power to the sensors and
thereby its performance is tested. This converter is compared with the conventional
method of supplying power to the sensor board and their performance
is observed in terms of efficiency and other parameters. The simulation results
are discussed and the performance is validated through experimental results.
Keywords: Fuel cell, Flyback converter, Active clamp, Sensor, RCD
snubber, Interleave, Two switch.
Enhancement of PQ Using Adaptive Theory
based Improved Linear Tracer Sinusoidal
Control Strategy for DVR doi: https://doi.org/10.13052/jge1904-4720.7129
J. Bangarraju1, V. Rajagopal2, Sabha Raj Arya3 and B. Subhash4
1B V Raju Institute of Technology, Narsapur, Medak District,
Telangana, India-502313
2Stanley College of Engineering and Technology for Women, Abids,
Hyderabad, India-500001
3S. V. National Institute of Technology, Surat, Gujarat, India-395007
4S. R. Engineering College, Warangal, Telangana, India-506371
Abstract: [+] | Download File [ 819KB ] | Read Article Online
Abstract: This paper presents the Adaptive Theory based Improved Linear Tracer
Sinusoidal (ATILS) Control Strategy for PQ Enhancement using DVR in
the Distribution System. The proposed DVR effectively mitigates voltage
sag/swell, unbalanced voltage sag/swell for linear loads along with harmonic
compensation using ATILS Control Strategy. The DVR consists of voltage
source converter (VSC), transformer with capacitor. The main advantages
are more efficiency, reliability and its effective control of reactive power.
The ATILS Control Strategy is used for extraction of fundamental reference
load voltages quickly and accurately to mitigate PQ problems. The
proposed ATILS Control Strategy for DVR is modeled using RT-LAB and
MATLAB/SIMULINK and its performance is verified for various Power
Quality (PQ) problems.
Keywords: DVR, ATILS Control Strategy, Power Quality, Harmonics,
Voltage sag/swell.
Abstract: Energy generation is facing a big challenge for meeting the load demand
during peak hours. Power utilities are heavily depending on fossil fuels due to
limited resources of non renewable energy generation. Therefore researchers
and scientists are looking towards some distributed generators (DGs) to supply
extra power during peak hours of energy curve. Solar power gives them an
extra sniff to meet the load demand in that period. As a consequence grid-tied
solar Photovoltaic (PV) system catches the eyes of researchers and industrialist
mainly for reducing the burden of fossil fuel energy generation. Single stage or
two stages PV systems are applicable for grid interconnection with or without
battery backup. Double stage system is generally suggested for practical
applications as it holds a benefit of power quality improvement. This article
presents a comprehensive review on grid-tied solar PV system. The complete
architecture of the grid-tied PV system includes the construction of PV
array, MPPT methods, DC-DC converters, Inverters and control algorithms.
Different control techniques and topologies with their merits and demerits
for grid-tied systems are thoroughly reviewed. The comparisons of different
conventional and advanced control techniques justify the practicability of this
architecture. Different topologies and control methods of grid-tied PV system
are studied thoroughly to justify the potential of grid-tied PV system.
Keywords: Grid Integration, Solar Photovoltaic, PVArray, Maximum Power
Point Tracking, DC-DC converter, Inverter.
Electric Vehicle Battery Charger with Improved Power Quality Cuk-Derived PFC Converter doi: https://doi.org/10.13052/jge1904-4720.71211
B. R. Ananthapadmanabha,1 Rakesh Maurya,1 Sabha Raj Arya1
and B. Chitti Babu2
1Department of Electrical Engineering, Sardar Vallabhbhai National Institute
of Technology, Surat-395007, India
2Department of Electrical and Electronics Engineering, University of Nottingham
(U.K) Malaysia Campus, 43500-Semenyih, Selangor, Malaysia
Abstract: [+] | Download File [ 1012KB ] | Read Article Online
Abstract: In this paper, an improved power quality converter derived from Cuk converter
is proposed for the electric vehicle battery charging under universal-input
voltage operation. The proposed converter offers high voltage gain, low
voltage stress across the switch, lower conduction losses and reverse recovery
losses during low input voltage condition. It yields improvement in efficiency
at the low input supply voltage over the single-switch converters such as
buck-boost, fly-back, SEPIC, and Cuk topologies and two-switch buck-boost
cascaded converters. The proposed converter is designed to operate in a
continuous conduction mode. The modeling and simulation of converter are
carried out in the Simulink environment ofMATLABsoftware. The developed
simulink model is validated by a prototype model of same specification using
Xilinx made Spartan3 processor under MATLAB environment in real time.
To investigate the performance of the converter in terms of power quality
indices like THD, input PF of source voltage and source current are evaluated
under constant voltage and constant current modes of battery charging, for wide range of supply voltage variations. The performance of the converter is
tested both in steady state and transient conditions.
Keywords: Cuk converter, Continuous Conduction Mode (CCM), Battery
charging, Harmonics, Power Factor Correction (PFC).
Abstract: Fuel cell based power generation is emphasized due to its capability of
supplying electricity in the areas where there are hardly any source of conventional
or non-conventional power generating options to adopt. Moreover,
the added advantage is that it can be used during peak loads. Fuel cell based
power generation is well known due to its clean operation, transportability,
suitability and flexibility for power generation. This paper gives the outlook
of modeling of a fuel cell power generation system, a multilevel inverter and
their control algorithms. The design system is used in isolated loads as well
as grid connected system. Different carrier signals have been used with two
different modulating signals for multilevel inverter for lowest Total Harmonic
Distortion (THD) in the output using seven levels and eleven level inverters.
The inverter output is fed to consumer loads. The MATLAB/SIMULINK
software is used for modeling this system. The developed fuel cell based distributed
power generation system worked satisfactorily, when it is connected
to grid and used in isolated mode or hybrid mode.
Keywords: Fuel cell, Multilevel inverter, modulation index, modulation
schemes, Total harmonic distortion (THD).
Abstract: This paper proposes a distributed resource management scheme to avoid
the need for energy storage and achieve the required frequency regulation.
The energy sources considered in the microgrid are Solar PhotoVoltaics
(SPV), Diesel Generators (DG), Fuel Cells (FC) and Plug-in Hybrid Electric
Vehicles (PHEV). The frequency regulation is done by considering the SPV
operation at a Limited-Power-Point (LPP) for spinning reserve using neurofuzzy
control in coordination withPHEVsand other sources. In vehicle-to-grid
(V2G) mode, State of Charge (SOC) of the battery in a PHEV shall be
the deciding factor in allowing it to participate in the regulation. A simple
additive-adaptive strategy based algorithm is proposed and tested in the
isolated microgrid environment. Satisfactory results of frequency regulation
were obtained upon consideration of scenarios, varying the load and insolation
in steps.
Keywords: Neuro-Fuzzy control, Frequency regulation, Energy management,
Limited-power-point-tracking, SolarPV, Fuel cells,V2G, Power quality.
