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Internet of things-based photovoltaics parameter monitoring system using NodeMCU ESP8266

10.11591/ijece.v11i6.pp5578-5587
Tole Sutikno , Hendril Satrian Purnama , Anggit Pamungkas , Abdul Fadlil , Ibrahim Mohd Alsofyani , Mohd Hatta Jopri
The use of the internet of things (IoT) in solar photovoltaic (PV) systems is a critical feature for remote monitoring, supervising, and performance evaluation. Furthermore, it improves the long-term viability, consistency, efficiency, and system maintenance of energy production. However, previous researchers' proposed PV monitoring systems are relatively complex and expensive. Furthermore, the existing systems do not have any backup data, which means that the acquired data could be lost if the network connection fails. This paper presents a simple and low-cost IoT-based PV parameter monitoring system, with additional backup data stored on a microSD card. A NodeMCU ESP8266 development board is chosen as the main controller because it is a system-on-chip (SOC) microcontroller with integrated Wi-Fi and low-power support, all in one chip to reduce the cost of the proposed system. The solar irradiance, ambient temperature, PV output voltage and PV output current, are measured with photo-diodes, DHT22, impedance dividers and ACS712. While, the PV output power is a product of the PV voltage and PV current. ThingSpeak, an open-source software, is used as a cloud database and data monitoring tool in the form of interactive graphics. The results showed that the system was designed to be highly accurate, reliable, simple to use, and low-cost.
Volume: 11
Issue: 6
Page: 5578-5587
Publish at: 2021-12-01

Enhancing performance of grid-connected photovoltaic systems based on three-phase five-level cascaded inverter

10.11591/ijpeds.v12.i4.pp2295-2304
Marwan E. Ahmad , Ali. H. Numan , Dhari Y. Mahmood
Multilevel inverters play an important role in power converters due to their good advantages. The cascaded H-bridge inverter is one of the most prominent and most suitable multilevel inverters in PV systems. Each H-bridge has a separate photovoltaic (PV) array as an independent direct current (DC) source. This paper introduces a three-phase cascaded H-bridge inverter with five levels connected to the grid to improve the performance and efficiency of the photovoltaic system. In the proposed system, each PV group has MPPT to extract the maximum power point from the PV group at certain irradiation and temperature and also to mitigate the mismatch that causes in the imbalance transmitted power from inverter to the main grid. The proposed control scheme with modulation compensation was used, and the system was simulated in MATLAB/Simulink with two different scenarios. The simulation results demonstrate the effectiveness of the proposed connection in minimizing the total harmonic distortion (THD) to acceptable limit, low overshoot, and fast-tracking to the desired value.
Volume: 12
Issue: 4
Page: 2295-2304
Publish at: 2021-12-01

A comparative study of meta-heuristic and conventional optimization techniques of grid connected photovoltaic system

10.11591/ijpeds.v12.i4.pp2492-2500
Mamadou Traore , Alphousseyni Ndiaye , Senghane Mbodji
This paper presents the meta-heuristic and conventional optimizations techniques for the grid connected photovoltaic solar system. The perturb and observe (P&O) and particle swarm optimization (PSO) algorithms are proposed to track the maximum power point (MPP) of the photovoltaic solar system (PVSS). The regularization of the current supplied into the grid is ensured by the proportional integral (PI) corrector whose parameters are generated by the genetic algorithm (GA). The results of these two MPPT methods are compared and showed that the PSO is more efficient than the P&O. The use of GA algorithm to determine PI parameters allowed to obtain 0.89% of total distortion harmonic (THD).
Volume: 12
Issue: 4
Page: 2492-2500
Publish at: 2021-12-01

A multi-input energy harvesting system with independent energy harvesting block and power management block

10.11591/ijeecs.v24.i3.pp1379-1391
Eun Jeong Yun , Hyeon Joong Kim , Chong Gun Yu
In the conventional approach widely used for multi-input energy harvesting (MIEH), energy harvesting, energy combining, and power conversion are performed integrally in an inductor sharing block through time multiplexing operations, which is not suitable for hot-pluggable systems. In the MIEH system proposed in this paper, an energy harvesting block (EHB) and a power management block (PMB) are independent of each other to increase the modularity of the system. Therefore, the EHB can be optimized to extract maximum power from energy sources, and the PMB can be focused on combining input energies and converting power effectively. This paper mainly focuses on the design and implementation of the EHB. For light, vibration, and thermal energy, the measured peak power efficiencies of the EHB implemented using a 0.35 μm CMOS process are 95.2%, 92.5%, and 95.5%, respectively. To confirm the functionality and effectiveness of the proposed MIEH system, a PMB composed of simple charge pump circuits and a power management unit has also been implemented and verified with the designed EHB.
Volume: 24
Issue: 3
Page: 1379-1391
Publish at: 2021-12-01

Narrow-band filter for satellite communication systems

10.11591/ijict.v10i3.pp198-203
Alexander Vladimirovich Strizhachenko , Sergey Nikolayevich Shulga
Design narrow-band compact filters, based on high-quality waveguide-dielectric resonators with anisotropic materials is the subject of this paper. Filter represents a segment of a rectangular waveguide rotated around the longitudinal axis of the waveguide 90 degrees and containing one or more dielectric inserts that completely fill the resonator along the narrow wall of the waveguide and partially along the wide one. A distinctive feature of the proposed filter is higher slope steepness of the amplitude-frequency characteristic, and high manufacturability in the centimeter range. The designed narrow-band filter satisfies contradictory requirements: it combines narrow bandwidth (≈ 0.1% of center frequency f0) with low passband insertion loss (≤ 1 dB).
Volume: 10
Issue: 3
Page: 198-203
Publish at: 2021-12-01

Arduino-based night return mechanism for passive solar trackers

10.11591/ijaas.v10.i4.pp335-342
Willy Stephen Tounsi Fokui , Destine Mashava
Solar trackers are support platforms that keep photovoltaic panels facing the sun by following the sun from dusk to dawn. There exist active solar trackers that make use of motors and gears to orientate the photovoltaic panels towards the sun; and passive solar trackers that operate through the differential heating of the fluid in the tracking rack to follow the sun. Passive solar trackers suffer from the lack of a night return mechanism and a slow wake-up response in the mornings due to the limitations on the surface inclination angle of the rack. This paper seeks to address these issues by proposing an Arduino-based night return mechanism for passive solar trackers. An energy-saving heating element such as the ultra heating fabric manufactured by WireKinetics Co. is installed on the west-side canister of the tracker. Before dawn, the fabric is automatically heated and this will force the refrigerant in the west-side canister to vaporize and cool in the east-side canister, forcing the tracker to return and face eastward before sunrise. The night return mechanism is designed and simulated using proteus profesional. Simulation results show that this system can significantly optimize the function of passive solar trackers.
Volume: 10
Issue: 4
Page: 335-342
Publish at: 2021-12-01

Intensifications reactive power during of asymmetric network outages in dual-stator winding generators

10.11591/ijpeds.v12.i4.pp2451-2458
Qasim Al Azze , Balasim М. Hussein , Hayder Salim Hameed
The paper proposes a protection to dual stator generator, reluctance rotor, from asymmetrical fault. Which prevents the dual stator generator, reluctance rotor, from electrical sage through working process in order to avoid any interruption in the generator-grid connection. The procedure consummated with injecting suitable reactive power during the fault period. The proposed method that makes it possible for wind turbine application via dual stator winding generators (DSWRG) synchronous mod to stay connected to the grid during asymmetrical faults. It has been built according to trusted simulating mode considering all tested parameters according to experiment work. The expirment, consider the DC link side stability and care about the behavior and performance of machine side parameter. As well the machineability is evaluated to ride through asymmetrical fault by observing the secondary side current which has a big role in saving grid side converter. The control takes a response within 200 ms after fault trigger recognition. The generator ability of dynamically remaining connected stable and existing in the network, which is sustained a series voltage disturbance by injecting appropriate amount of reactive power. The main interest required in this paper is the capability of a machine to overcome the asymmetrical fault.
Volume: 12
Issue: 4
Page: 2451-2458
Publish at: 2021-12-01

A small vessel detection using a co-located multi-frequency FMCW MIMO radar

10.11591/ijece.v11i6.pp5144-5152
Suraya Zainuddin , Nur Emileen Abd Rashid , Idnin Pasya , Raja Syamsul Azmir Raja Abdullah , Korhan Cengiz
Small vessels detection is a known issue due to its low radar cross section (RCS). An existing shore-based vessel tracking radar is for long-distance commercial vessels detection. Meanwhile, a vessel-mounted radar system known for its reliability has a limitation due to its single radar coverage. The paper presented a co-located frequency modulated continuous waveform (FMCW) maritime radar for small vessel detection utilising a multiple-input multiple-output (MIMO) configuration. The radar behaviour is numerically simulated for detecting a Swerling 1 target which resembles small maritime’s vessels. The simulated MIMO configuration comprised two transmitting and receiving nodes. The proposal is to utilize a multi-frequency FMCW MIMO configuration in a maritime environment by applying the spectrum averaging (SA) to fuse MIMO received signals for range and velocity estimation. The analysis was summarised and displayed in terms of estimation error performance, probability of error and average error. The simulation outcomes an improvement of 2.2 dB for a static target, and 0.1 dB for a moving target, in resulting the 20% probability of range error with the MIMO setup. A moving vessel's effect was observed to degrade the range error estimation performance between 0.6 to 2.7 dB. Meanwhile, the proposed method was proven to improve the 20% probability of velocity error by 1.75 dB. The impact of multi-frequency MIMO was also observed to produce better average error performance.
Volume: 11
Issue: 6
Page: 5144-5152
Publish at: 2021-12-01

Trend of the spread of COVID-19 in Indonesia using the machine learning prophet algorithm

10.11591/ijeecs.v24.i3.pp1780-1788
Nur Hayati , Fauziah Fauziah , Dendi Rizka Poetra , Dede Wandi
Based on information on the BNPB website on 2 September 2020, the positive rate for coronavirus disease (COVID-19) in Indonesia reached 25.25% on 30 August 2020. This is a big challenge for the Indonesian government to reduce the positivity rate to meet the standards safe accepted by World Health Organization (WHO) is 5%. To ensure the accuracy of government policies, accurate data predictions are needed. Therefore, the prophet's machine learning algorithm can be used to see trends in the spread of COVID-19 in the next one year. This algorithm has a fairly high level of accuracy because the data contains time variables which are adjusted to the dataset. In several previous research, the dataset was vast uncertain and small. Meanwhile in this research, data was taken from 2 March 2020 to 12 February 2021 on the KawalCOVID19 website. This data is used to predict from 13 February 2021 to 12 February 2022. There are 3 data used; namely data confirmed, recovered and died. Based on the analysis, the confirmed patient was 22.60-42.11%, died amounted to 21.67%-39.00%, and recovered by 22.53-41.82%. The prediction percentage that the average cases died was 2.43% every day. The accuracy of data confirmed was 43.97%, died was 72.50% and recovered was 84.24%.
Volume: 24
Issue: 3
Page: 1780-1788
Publish at: 2021-12-01

An efficient hybrid reconfigurable wind gas turbine power management system using MPPT algorithm

10.11591/ijpeds.v12.i4.pp2501-2510
Manjunath T. N. , Mallikarjunaswamy S. , Komala M. , Sharmila N. , Manu K. S.
To improve power management scheme in standalone mode using hybrid wind-gas turbine system. To reduce electrical fluctuations due to permanent magnet synchronous generator (PMSG) in wind turbine system. For power generation, the wind turbine system is a main source. When there is reduction in wind turbine power generation, then gas turbine gets activated immediately and produces the required electricity in effective manner. This reconfigurable power generation system is controlled by perturb and observe maximum power point tracking (P&O_MPPT) algorithm. The proposed wind-gas power management system algorithm and device performance was analysed and simulated using MATLAB R2021a for various wind turbine experiment parameters. The simulation result shows that the proposed model and algorithm effectively meets the load demand when the wind turbine speed falls below the minimum required value.
Volume: 12
Issue: 4
Page: 2501-2510
Publish at: 2021-12-01

Lifestyle breast cancer patients among Indonesian women: A nationwide survey

10.11591/ijphs.v10i4.20913
Solikhah Solikhah , Khairunnisaa Nuur Aliifah Setyawati , Monthida Sangruangake
Recently, cancer is a major health problem in the world. Lifestyle changes and growing urbanization likely led to increasing breast cancer incidence in such in Indonesia. Therefore, this study aimed to explore lifestyle breast cancer patients among Indonesian women. The investigation was a cross-sectional study distributed among 3,392 females drawn from 13 out of 27 provinces in Indonesia. Multiple binary logistic regressions were conducted to investigate breast cancer risk among Indonesian. A significance level of 0.05 was employed in all analysis. Of the 3,392 respondents included in the analysis, more than half (52.71%; n=1,788) was aged 40–49 years old. The most common marital status of the participants was married (98.20%; n=3,331), followed by no smoking (94.69%; n=3,212) and active exercise (62.12%; n=2,107). Education level was significantly associated with breast cancer (AdjOR_Junior high school=0.21; 95%CI=0.06 to 0.70; p<0.01 and AdjOR_senior high school=0.60; 95%CI=0.15 to 2.26; p<0.05). Education level was significantly related to breast cancer. Lifestyle such as smoking and physical activity was suspected to affect breast cancer indirectly.
Volume: 10
Issue: 4
Page: 730-734
Publish at: 2021-12-01

Predictive ability of problem-solving efficacy sources on mathematics achievement

10.11591/ijere.v10i4.21416
Januard D. Dagdag , Noel A. Palapuz , Nikka A. Calimag
This study examined the relationship between mathematics achievement and mathematics problem-solving efficacy sources. A cluster sample of 123 first year prospective teachers of a Philippine higher education institution responded to a 30-item problem-solving efficacy scales and took the teacher-made tests in Mathematics in the Modern World course; namely, Non-Routine Problem Solving and Natures and Numbers Pattern Tracing (NRPS-NNPT), Math Language and Symbols (MLS), and Data Management (DM). The research data was analyzed using Descriptive statistics, Pearson-r and Standard Multiple Regression. On the average, the respondents had satisfactory mathematics achievement. They reported a high level of social persuasion and somatic response and a low level of vicarious experience and mastery experience in mathematics problem-solving. Vicarious experience was directly associated with mastery experience while social persuasion and mastery experience were both inversely related to somatic responses. Among the four problem-solving efficacy sources, only social persuasion significantly predicted mathematics achievement specifically in the areas of NRPS-NNPT, MLS, and DM. Thus, becoming a trusted voice of encouragement and designing a persuasive and optimistic learning environment are highly recommended roles of schools to facilitate students’ mathematics achievement.
Volume: 10
Issue: 4
Page: 1185-1191
Publish at: 2021-12-01

Optimal tuning of PI controller using system identification for two-phase boost converter for low-voltage applications

10.11591/ijpeds.v12.i4.pp2393-2402
M. A. N. Amran , A. A. Bakar , M. H. A. Jalil , A. F. H. A. Gani , E. Pathan
This paper presents modeling and hardware implementations of a two-phase DC-DC boost converter by using the system identification approach. The main objective of this research was to study new methods to obtain the values of the constants for the proportional-integral (PI) controller. Existing methods are time-consuming, since the values of the constants for the PI controller need to be calculated. The system identification approach for the closed-loop boost converter saves more time. This method has the fastest technique to find constants Kp and Ki for the closed-loop two-phase boost converter. To model a two-phase boost converter using the system identification approach, input duty cycle and output voltage are collected in the time domain data. In this study, the transfer function (TF) model, the autoregressive moving average with exogenous (ARMAX) model and the output-error (OE) model were used to generate a mathematical model. To perform the closed-loop analysis, constants Kp and Ki were obtained based on the generated mathematical model from the system identification approach. The result from the experiment shows that the percentages of overshoot for the TF, ARMAX and OE models were 19%, 25.36% and 24.6%, respectively. The output voltage ripples obtained for all three models were less than 5% of output voltage.
Volume: 12
Issue: 4
Page: 2393-2402
Publish at: 2021-12-01

A single-stage full bridgeless boost half-bridge AC/DC converter with bidirectional switch

10.11591/ijpeds.v12.i4.pp2336-2348
Mohamad Affan Bin Mohd Noh , Mohd Rodhi Bin Sahid , Vinesh Thiruchelvam
This paper proposes an isolated full bridgeless single stage alternating current-direct current (AC-DC) converter. The proposed converter integrates the operation of a pure bridgeless power factor correction with input boost inductor cascaded with center-tap transformer and half bridge circuit. In addition, the bidirectional switch can be driven with single control signal which further simplifies the controller circuit. It is also proved that this converter reduces the total number of components compared to some conventional circuit and semi-bridgeless circuit topologies. The circuit operation of the proposed circuit is then confirmed with the small signal model, large signal model, circuit simulation and then verified experimentally. It is designed and tested at 115 Vac, 50 Hz of input supply, and 20 Vdc output voltage with maximum output power of 100 W. In addition, the crossover distortion at the input current is minimize at high input line frequency.
Volume: 12
Issue: 4
Page: 2336-2348
Publish at: 2021-12-01

The correlation between metacognitive skills and scientific attitudes towards the retention of male and female students in South Sulawesi, Indonesia

10.11591/ijere.v10i4.21597
Romi Adiansyah , Aloysius Duran Corebima , Siti Zubaidah , Fatchur Rohman
This was quantitative correlational research, which investigated the correlation between metacognitive skills and scientific attitudes towards the retention of male and female students in South Sulawesi, Indonesia. The research sample was biology education students in the second semester, with 104 students consisting of 47 males and 57 females. The instruments employed in this study were those for assessing metacognitive skills, scientific attitudes, and retention. Metacognitive skills and retention were measured using essay tests, while scientific attitudes were measured using observation sheets. The results indicated that the value of the simultaneous contribution of metacognitive skills and scientific attitudes towards to the retention of female students was higher than that of male students. The effective contributions of metacognitive skills and scientific attitude towards male students' retention were 3.33% and 24.67%. Metacognitive skills and scientific attitudes both contribute 14.5% and 17.2%, respectively, to female students’ retention.
Volume: 10
Issue: 4
Page: 1272-1281
Publish at: 2021-12-01
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