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29,922 Article Results

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

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

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

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

The determinant factors of school organizational change in Madura, East Java, Indonesia

10.11591/ijere.v10i1.20532
Mochammad Rozikin , Abd. Qadir Muslim , Bayu Indra Pratama
Organizational change is a phenomenon that must be faced and carried out by every individual in the organization to achieve organizational goals. Embodiments of organizational change often occur not because it suits the needs of the organization but because of personal interests and power. This study aimed to determine the main factors that can create change, namely the relationship of leadership and political pressure of school principals that influence organizational change in the Public Secondary School in Madura, East Java, Indonesia. This research used a quantitative approach to survey methods. Based on the achievement of its objectives, this study included causal explanation research, the analysis of this study using Structural Equation Modeling (SEM) and a sample of about 650 people collected from 1000 respondents taken from 130 schools through probability sampling techniques using AMOS software. The results showed that the leadership and political pressure of regional heads were the main factors of organizational change at SMPN (Public Secondary School) in Madura, East Java. Organizational Change depends very much on the role of the political pressure of the regional head through education policy, as well as the role of the principal's leadership in running the wheels of the organization so that the school's goals can be achieved. This study also showed that the principal's leadership as an intermediary variable from political pressure shows no influence because the political pressure of the regional head is directly related to organizational change.
Volume: 10
Issue: 1
Page: 308-316
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

Crucial problems in arranged the lesson plan of vocational teacher

10.11591/ijere.v10i1.20604
Muhammad Nurtanto , Nur Kholifah , Alias Masek , Putu Sudira , Achmad Samsudin
This study aimed to explore the implementation of the 2013 curriculum in vocational schools, Banten in terms of the readiness and quality of the learning tools that have been prepared. A total of 957 respondents from 2017 to 2018, consisting of four cities and three districts in Banten Province were involved in the training and mentoring program, namely vocational teachers and vice-principals in the curriculum field. Data were collected using questionnaire sheets, FGD notes, and observation check dates. The data obtained are analyzed and interpreted based on the specified categories. The results showed that: 1) Teacher readiness for learning tools in the components a) Core Competencies (CC) and Basic Competencies (BC) analysis of 45.31%, b) Program mapping of 38.37%, learning plan preparation of 39.45% and c) Learning evaluation of 36.78%; 2) The quality of lesson plan (LP) the science lesson plan analysis instrument (SLPAI) based is divided into two groups. The category "Quality" in the instructional program and instructional plan aspects, and the category "Moderate" in the instructional media and assessment and others aspects; and 3) The difficulty of learning device components, including authentic assessment, use of methods, literacy approaches, and lesson planning. The implementation of training, mentoring, and supervision programs are adjusted to the experience of vocational teachers taking into account the teacher's involvement in the implementation of the curriculum, age, and school readiness.
Volume: 10
Issue: 1
Page: 345-354
Publish at: 2021-03-01

Active damping method for voltage source inverter-based distributed generator using multivariable finite-control-set model predictive control

10.11591/ijpeds.v12.i1.pp334-344
Jonggrist Jongudomkarn , Warayut Kampeerawat
Despite its advantages, the LCL filter can significantly distort the grid current and constitute a substantially more complex control issue for the grid-connected distributed generators (DGs). This paper presents an active damping approach to deal with the LCL filter's oscillation for the finite-control-set model predictive control (FCS-MPC)-three-phase voltage source inverters (VSIs)-based DG. The new approaches use the multivariable control of the inverter side's filter current and capacitor voltage to suppress the LCL filter resonance. The proposed method has been tested in steady-state and under grid voltage disturbances. The comparative study was also conducted with the existing virtual resistance active damping approaches for an FCS-MPC algorithm. The study validates the developed control schemes' superior performance and shows its ability to eliminate lower-order grid current harmonics and decrease sensitivity to grid voltage distortion.
Volume: 12
Issue: 1
Page: 334-344
Publish at: 2021-03-01

Finite frequency H∞control design for nonlinear systems

10.11591/ijpeds.v12.i1.pp567-575
Zineb Lahlou , Abderrahim EL-Amrani , Ismail Boumhidi
The work deals finite frequency H∞ control design for continuous time nonlinear systems, we provide sufficient conditions, ensuring that the closed-loop model is stable. Simulations will be gifted to show level of attenuation that a H∞ lower can be by our method obtained developed where further comparison.
Volume: 12
Issue: 1
Page: 567-575
Publish at: 2021-03-01

Investigation of faulty behavior of the sensorless control switched reluctance motor drives

10.11591/ijpeds.v12.i1.pp88-98
Alexander Krasovsky
The paper presents the results of studies of abnormal conditions in a switched reluctance drive (SRD) due to failures in control algorithms. It discusses one of the most common control algorithms for these drives without the use of sensors, which is simple and easy to configure. The practical application of this algorithm of control showed that various anomalous phenomena could occur in it, expressed, for example, in a sharp increase in the amplitude of the phase current of the motor, and violation of the switching mode. The reasons for these phenomena are not evident and hard to analyze due to the nonlinearity of this drive. To identify these causes and search for measures to eliminate them, we used simulation in the environment of MATLAB/Simulink. The adequacy and effectiveness of the application of the developed simulation models we confirmed by a comparison of the simulation results and the full-scale experiment on real equipment. Theoretical studies and simulation results are in good agreement with the experimental results.
Volume: 12
Issue: 1
Page: 88-98
Publish at: 2021-03-01
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