Articles

Access the latest knowledge in applied science, electrical engineering, computer science and information technology, education, and health.

Advanced Search
Filter Icon

Filters article

Years

FAQ Arrow
Single Year
Range Year
0
0

Source Title

FAQ Arrow

Authors

FAQ Arrow

31,456 Article Results

State feedback control of advanced static var compensator using a five-level NPC inverter topology

10.11591/ijpeds.v12.i1.pp345-355
Mansour Benyamina , Ali Tahri , Abdelkader Boukortt
This paper deals with the modeling and control of an advanced static var compensator (ASVC) using a five-level neutral point-clamped (NPC) voltage source inverter (VSI). The nonlinear state space model of the five-level ASVC is obtained from the d-q axis frame. The effectiveness of this compensator highly depends on the choice of the control strategy. The proposed state feedback control (SFC) technique is applied to adjust the ASVC Var flow with the AC transmission network and achieve DC voltage capacitor balance. The dynamic performance of the ASVC based SFC controller is evaluated under several operating conditions. The simulation results demonstrate that the proposed SFC control strategy is highly robust compared to the conventional Proportional-Integral (PI) control.
Volume: 12
Issue: 1
Page: 345-355
Publish at: 2021-03-01

Multilevel diode clamped D-Statcom for power quality improvement in distribution systems

10.11591/ijpeds.v12.i1.pp217-227
Jasti Venkata Ramesh Babu , Malligunta Kiran Kumar
Power quality is one big issue in power system and a big challenge for power engineers today. Electrical consumers (or otherwise load devices) expect electrical power received power should be of first-class. Bad quality in electrical power directs to fuse blowing, machine overheating, increase in distribution losses, damage to sensitive load devices and many more. DSTATCOM is one of the FACTS controllers designed to improve the quality in electrical power and thus improving the performance of distribution system. This paper presents a multilevel DSTATCOM topology to enhance power quality in power distribution system delivering high-quality power to the customer load devices. Diode-clamped structure is employed for multi-level DSTATCOM structure. ‘PQ’ based control strategy generates reference signal which is further processed through level-shifted multi-carrier PWM strategy for the generation of gate pulses to multi-level DSTATCOM structure. Simulation work of proposed system is developed and the result analysis is presented using MATLAB/SIMULINK software. Performance of multi-level DSTATCOM topology is verified with fixed and variable loads.
Volume: 12
Issue: 1
Page: 217-227
Publish at: 2021-03-01

Mitigating the dead-time effects on harmonics spectrum of inverter waveform by the confined band VSFPWM technique

10.11591/ijpeds.v12.i1.pp295-303
Hussain Attia , Hang Seng Che , Tan Kheng Suan Freddy , Ahmad Elkhateb
The dead-time is necessary to be inserted between the gates drive pulses of the two power electronic switches in a one leg of any inverter to avoid a short circuit in the leg and the DC supply as well. However, adding the dead-time increases the low order harmonics of the output voltage/current waveform of the inverter. This paper investigates the positive effects of decreasing the pulse width modulation (PWM) drive pulses number per fundamental period on the current low order harmonics. In addition, this paper evaluates the impact of the confined band variable switching frequency pulse width modulation (CB-VSFPWM) technique on inverter performance in terms of dead-time mitigating, and consequenctely lowering the low order harmonics. CB-VSFPWM technique reduces the total harmonic distortion (THD) levels in the inverter output current as well. Theoretical analysis of the CB-VSFPWM effectiveness in reducing the negative effect of the dead-time has explained in this study and confirmed by the MATLAB/Simulink simulation results.
Volume: 12
Issue: 1
Page: 295-303
Publish at: 2021-03-01

Analysis on three phase cascaded H-bridge multilevel inverter based on sinusoidal and third harmonic injected pulse width modulation via level shifted and phase shifted modulation technique

10.11591/ijpeds.v12.i1.pp160-169
A. Shamsul Rahimi A. Subki , Zahariah Manap , Mohd Zaidi Tumari , Aiman Zakwan Jidin , Shahrizal Saat , Amar Faiz Zainal Abidin , Muhammad Salihin Saealal
This work proposes a comparative analysis of sinusoidal and third harmonic injected reference signal modulation accompany with level-shifted PWM technique named as phase disposition (LSPD), phase opposition disposition (LSPOD), and alternate phase opposition disposition (LSAPOD) and phase-shifted PWM technique. Switching pulses from both reference signal and PWM technique have been fed into three phase eleven level cascaded H-bridge multilevel inverter (CHBMLI) fed on a resistive-inductive load with the modulation depth (MD) set to varied from 80% to 100%. For voltage source inverter, total harmonic distortion (THD) content is critical and must be within the allowable range. To prove the feasibility of the reference signal with carrier signal schemes, the entire simulation of the modulation techniques is established and conducted via the Simulink environment. According to the analyzed result, the performance is acceptable in terms of %THDV and %THDI values. Simulation analysis also indicates, at full modulation depth, due to higher fundamental output voltage component produces via the THIPWM modulation technique compared to the SPWM technique, this causes higher %THDV value.
Volume: 12
Issue: 1
Page: 160-169
Publish at: 2021-03-01

Arabic language learning reconstruction as a response to strengthen Al-Islam studies at higher education

10.11591/ijere.v10i1.20747
Mahyudin Ritonga , Hendro Widodo , Munirah Munirah , Talqis Nurdianto
Knowledge of the Islam at every student is supported by many factors, one of which is the Arabic language compentence. This research aimed to evaluate and find Arabic language learning construction in strengthening al-Islam at higher education. The desire to find the construction is because there is no visible connection between Arabic language learning and al-Islam learning so that clarity of learning objectives, learning materials, learning implementation, and evaluation systems of Arabic language learning at higher education is needed. In line with this purpose, this study used a qualitative method with a phenomenological approach. The sources of data were facts, Arabic language lecturers, al-Islam lecturers, and students purposively. Data were analyzed by using critical realism. The results of the study proved that the reconstruction of learning objectives, materials, implementation, and evaluation systems is needed to realize Arabic language learning that can strengthen al-Islam at higer education.
Volume: 10
Issue: 1
Page: 355-363
Publish at: 2021-03-01

Allocating active power loss with network reconfiguration in electrical power distribution systems

10.11591/ijpeds.v12.i1.pp130-138
Ambika Prasad Hota , Sivkumar Mishra , Debani Prasad Mishra , Surender Reddy Salkuti
This paper presents a branch exchange (BE) based heuristic network reconfiguration technique where, the proposed bus classification strategy remodels dynamically as per the modified topology in order to provide a reconfigured network with minimum loss. Further, for fair allocation of the active power losses, it develops a new active power loss allocation (APLA) technique which eradicates the influence of cross-term analytically from loss formulation without any assumptions and approximations. The effectiveness of the proposed procedure has been investigated against other established methods using a 69-bus radial distribution network (RDN). The results of APLA achieved for original and reconfigured 69-bus RDN are found to be promising and judicious as regard to their load demands and geographical locations. The implementation of present reconfiguration procedure provides a total loss reduction benefit of 55.73% to the utility which highlights the significance of the developed procedure against other established techniques.
Volume: 12
Issue: 1
Page: 130-138
Publish at: 2021-03-01

Reducing torque pulsations in PMa-SynRM: a way for improving motor performance

10.11591/ijpeds.v12.i1.pp67-79
Percy R. Viego , Julio R. Gómez , Vladimir Sousa , José P. Monteagudo Yanes , Enrique C. Quispe
This paper aims to evaluate the performance of synchronous reluctance motors assisted by a permanent magnet (PMa-SynRM) focused on efficiency and torque pulsations. PMa-SynRM shows high efficiency and power factor, compared to induction motors (IM), although they have a greater cost. These machines develop relatively high torque ripple, cogging torque, and torque imbalances. Consequently, the electromagnetic torque is reduced, the motor temperature is increased, and mechanical vibrations are induced. The optimal design of the machine structures such as flow barriers, permanent magnets, and stator slots, among others, allow reducing torque pulsations. A comparison is made between different designs of the PMa-SynRM reported in the scientific literature, and the effects on efficiency, torque pulsation, and operating costs are evaluated. A case study on the motor driving the air conditioner blower in a hotel room was made, to determine the best economic variant between IM or PMa-SynRM. A sensitive analysis was made to evaluate several uncertainties. The advantages of using one of the PMa-SynRM analyzed were demonstrated. Also, it was proved that the investment is feasible economically, although NPV and payback are not the best, due to low load factor in inverter-controlled motors in air conditioners.
Volume: 12
Issue: 1
Page: 67-79
Publish at: 2021-03-01

Active battery balancing system for electric vehicles based on cell charger

10.11591/ijpeds.v12.i1.pp385-392
Amin Amin , Alexander Christantho Budiman , Sunarto Kaleg , Sudirja Sudirja , Abdul Hapid
Cell imbalance can cause negative effects such as early stopping of the battery charging and discharging process which can reduce its capacity. In the previous active balancing research, the energy used for the balancing process was taken from the cell or battery pack, resulting in drop of electric vehicle driving range. In this paper, a cell charger based battery balancing system is proposed with a reduction in the number of switches. The use of a cell charger aims to increase the usable energy of the battery pack, since the energy used for the balancing process is taken directly from the grid. The use of fewer switches aims to reduce the cost and space used on the battery management system (BMS) hardware. The charger used for the balancing process has a maximum current of 3 A and a maximum voltage of 3.65 V while the number of switches used is n+5 for n batteries. A 15S1P 200 Ah LiFePO4 battery pack consists of 15 cells used for testing purpose. The test results show that the time needed to equalize the 15 cell battery voltage reaches 6 hours from the difference between the highest and lowest battery cell voltages of 145.1 mV to 15.1 mV.
Volume: 12
Issue: 1
Page: 385-392
Publish at: 2021-03-01

Assessing students’ errors in mathematical translation: From symbolic to verbal and graphic representations

10.11591/ijere.v10i1.20819
Nurrahmawati Nurrahmawati , Cholis Sa'dijah , Sudirman Sudirman , Makbul Muksar
Translation skills are very important possessed by students, but currently, there are still many students who have difficulty in translating between representations. The purpose of this study is to analyze students' errors in translating from symbolic representations to verbal and graphic representations. This research was descriptive study with qualitative approach. Tests are given to junior high school students. From the results of data analysis, it is obtained that in translating from symbolic to verbal forms (problems in daily life) that are following the given system of equations, students are still unable to make representations correctly. When students are asked to translate into graphical form, students are still unable to draw complete graphs and errors made by students are misinterpretation and implementation errors, so they cannot maintain the semantic congruence between source representation and target representation. Based on this, it is necessary to make a learning plan that can improve students’ ability to translate between representations.
Volume: 10
Issue: 1
Page: 115-125
Publish at: 2021-03-01

Effect of partial shading in grid connected solar PV system with FL controller

10.11591/ijpeds.v12.i1.pp431-440
K Latha Shenoy , C. Gurudas Nayak , Rajashekar P. Mandi
As conventional fossil fuel reserves shrink and the danger of climate change prevailing, the need for alternative energy sources is unparalleled. A smart approach to compensate the dependence on electricity generated by burning fossil fuels is through the power generation using grid connected PV system. Partial shading on PV array affects the quantity of the output power in photovoltaic (PV) systems. To extract maximum power from PV under variable irradiance, variable temperature and partial shading condition, various MPPT algorithms are used. Incremental conductance and fuzzy based MPPT techniques are used for maximum power extraction from PV array. Basically 11 kW Solar PV system comprising of PV array coupled with an Inverter through a dc-dc converter is considered for the analysis and output of the inverter is supplied to the load through the LCL filter. An Intelligent controller for maximum power point tracking of PV power is designed. Also, a fuzzy controller for VSC is developed to improve the system performance. The above proposed design has been simulated in the MATLAB/Simulink and analyzed the system performance under various operating conditions. Finally, the performance is evaluated with IEEE 1547 standard for showing the effectiveness of the system.
Volume: 12
Issue: 1
Page: 431-440
Publish at: 2021-03-01

Deep learning model for glioma, meningioma, and pituitary classification

10.11591/ijaas.v10.i1.pp88-98
Toqa A. Sadoon , Mohammed H. Ali
One of the common causes of death is a brain tumor. Because of the above mentioned, early detection of a brain tumor is critical for faster treatment, and therefore there are many techniques used to visualize a brain tumor. One of these techniques is magnetic resonance imaging (MRI). On the other hand, machine learning, deep learning, and convolutional neural network (CNN) are the state of art technologies in recent years used in solving many medical image-related problems such as classification. In this research, three types of brain tumors were classified using magnetic resonance imaging namely glioma, meningioma, and pituitary gland on the based of CNN. The dataset used in this work includes 233 patients for a total of 3,064 contrast-enhanced T1 images. In this paper, a comparison is presented between the presented model and other models to demonstrate the superiority of our model over the others. Moreover, the difference in outcome between pre- and post-data pre-processing and augmentation was discussed. The highest accuracy metrics extracted from confusion matrices are a precision of 99.1% for the pituitary, a sensitivity of 98.7% for glioma, a specificity of 99.1%, and an accuracy of 99.1% for the pituitary. The overall accuracy obtained is 96.1%.
Volume: 10
Issue: 1
Page: 88-98
Publish at: 2021-03-01

Deployment of internet of things-based cloudlet-cloud for surveillance operations

10.11591/ijai.v10.i1.pp24-34
Edje E. Abel , Abd Latiff Muhammad Shafie , Weng Howe Chan
This research proposes the design of internet of things (IoT) camera/toxic gas sensors for the surveillance of a nation’s borders. Also, a wearable radio frequency identification (RFID) tag with built-in body-temperature/heartbeat sensors, for monitoring the health status and locations of military personnel while on border patrol duty or in battlefield combats. Mobile micro-controllers are deployed to gather sensed data retrieved from the sensors/RFID tags and transmitted to a cloudlet situated at the command control center, located 200 meters away from the sensor devices. Consequently, sensed data are dispatch to the cloud data center when there is a need for offline data mining or analysis. The distinguishing feature of our proposed system from previous researches is that the health status and locations of troops (soldiers) are monitored while they are in border patrol duty or in battlefield combats. Also, the introduction of cloudlet services closer to the IoT sensor devices for collection of sensed data. This way, the sensed data or information gathered at the cloudlet will aid timely information retrieval that will speed up intelligence gathering for strategic military operations, especially in critical situations. This is an innovative attempt to apply IoT-enabled cloudlet-based cloud computing to support military operations.
Volume: 10
Issue: 1
Page: 24-34
Publish at: 2021-03-01

Proposed synchronization circuits connecting wind driven DFIG to the public grid

10.11591/ijpeds.v12.i1.pp151-159
Mohamed Hussein Agamy , Fathe M. Allythi , Adel S. Nada
This paper presents a tested proposal scheme to connect a DFIG driven by a wind turbine to the public grid. This scheme was implemented to drive an automatic transfer switch (ATS). Control of the phase sequence, phase difference, and the frequency of the injected power are achieved using these proposed control circuits. These circuits are practically implemented and laboratory tested. The system allows monitoring the rated frequency, synchronization, and fundamental magnitude. Simulation software such as Multi Sim and Proteus are used for system validation and compatibility. The implemented circuits are used for re-scaling the grid voltage to the logic level for real time comparison and calculations. In addition to the feature of data monitoring, the system can also log these data for the system debugging purposes. The system can be considered as a real time control where the measurements and the correction are made in few milliseconds (fractions of the fundamental cycle). The lower cost control circuits are implemented using an Arduino kit in addition to a discrete digital component. The simulation and experimental results are in satisfactory agreement showing the most salient features of this system.
Volume: 12
Issue: 1
Page: 151-159
Publish at: 2021-03-01

Improvement of sliding mode power control applied to wind system based on doubly-fed induction generator

10.11591/ijpeds.v12.i1.pp441-452
Btissam Majout , Douae Abrahmi , Yasmine Ihedrane , Chakib El Bakkali , Karim Mohammed , Badre Bossoufi
In this work, we are interested in improving the performance of a doubly-fed induction generator (DFIG)-based wind system, by applying a sliding mode control strategy. The objective is the regulation of the active and reactive power, also the voltage and the frequency of the signal injected into the distribution network. The model proposed for the control is based on the sliding mode technique with performance estimators. The proposed model was validated by a simulation on MATLAB/Simulink.
Volume: 12
Issue: 1
Page: 441-452
Publish at: 2021-03-01

Real time face recognition of video surveillance system using haar cascade classifier

10.11591/ijeecs.v21.i3.pp1389-1399
Adlan Hakim Ahmad , Sharifah Saon , Abd Kadir Mahamad , Cahyo Darujati , Sri Wiwoho Mudjanarko , Supeno Mardi Susiki Nugroho , Mochamad Hariadi
This project investigates the use of face recognition for a surveillance system. The normal video surveillance system uses in closed-circuit television (CCTV) to record video for security purpose. It is used to identify the identity of a person through their appearances on the recorded video, manually. Today’s video surveillance camera system usually not occupied with a face recognition system. With some modification, a surveillance camera system can be used as face detection and recognition that can be done in real-time. The proposed system makes use of surveillance camera system that can identify the identity of a person automatically by using face recognition of Haar cascade classifier. The hardware used for this project were Raspberry Pi as a processor and Pi Camera as a camera module. The development of this project consist of three main phases which were data gathering, training recognizer, and face recognition process. All three phases have been executed using Python programming and OpenCV library, which have been performed in a Raspbian operation system. From the result, the proposed system successfully displays the output result of human face recognition, with facial angle within ±40°, in medium and normal light condition, and within a distance of 0.4 to 1.2 meter. Targeted image are allowed to wear face accessory as long as not covering the face structure. In conclusion, this system considered, can reduce the cost of manpower in order to identify the identity of a person in real time situation.
Volume: 21
Issue: 3
Page: 1389-1399
Publish at: 2021-03-01
1 2 3
...
2097 2098
Show 1097 of 2098

Discover Our Library

Embark on a journey through our expansive collection of articles and let curiosity lead your path to innovation.

Explore Now
Library 3D Ilustration