13 research outputs found
Failure detection analysis of grid-connected photovoltaic systems in tropical climate region / Nurmalessa Muhammad @ Atan
Get PDFMonitoring of photovoltaic (PV) system performance for optimum energy output in Malaysian climate is crucial due to the rapid development of PV system installation and application. For tropical climate condition, most of the related studies were on fault detection with very few were on failure detection (FD). Therefore, the aim of the study is to identify a fast, simple, and reliable method of FD on GCPV system in Malaysia. The objectives were: to develop the FD algorithm in GCPV system, to identify the types of fault occurrence in FD in GCPV system, and to verify the FD algorithm to be performed in Malaysian climate. The sources of data in this study were obtained from five sites in the testing and commissioning (T&C) of PV systems from Feed-in-Tariff (FiT) scheme under Sustainable Energy Development Authority (SEDA), and Green Energy Research Centre (GERC) Universiti Teknologi MARA (UiTM), Malaysia. Two additional sites from T&C of the FiT scheme were used for the verification of the new developed FD algorithm. These sites are in the Peninsular of Malaysia. Filtration and identification processes were performed to ensure the selection of reliable data. The FD algorithm has employed mathematical and statistical approaches to establish the relationship between the parameters. A modified threshold-based technique was used to build the FD algorithm based on data from PV system installed at GERC UiTM, Malaysia. The establishment of threshold value for DC array current ratio, Rc and DC string voltage ratio, Rv is optimal for the used in Malaysian climate conditions. The threshold value for Rc and Rv is 0.9721 and 0.9410, respectively. The results have shown the FD algorithm has successfully identified the types of failure occurrence in all the five PV systems. Finally, the verification on the two additional sites of FD algorithm has detected the 'No Fault' and 'Fault' as suggested by the type of failure occurrence and failure identification technique
Role of plasticizers in enhancing the transport properties of ENR polymer electrolytes for electrochemical systems / Nurmalessa Muhammad @ Atan.
Get PDFIn this study, ENR-50 (epoxidised natural rubber) containing different concentrations of lithium triflate (LiCF3SO3) salt concentrations were prepared using a solution cast technique. Impedance spectroscopy (IS) technique was carried out to determine the electrical conductivity value samples. The highest value of electrical conductivity for the optimum percentage salt of the sample was determined. The highest conductivity was 1.98 x 10-5 S crn-1 for 1.0 g ENR-50 + 35 wt% LiCF3S03. This conductivity was calculated using the bulk resistance value which can be obtained from the complex impedance plot in frequency range between 100 Hz and 1 MHz. Plasticizers such as propylene carbonate (PC) and ethylene carbonate (EC) with LiCF3SO3 different weight percent has been added to ENR-50 + LiCF3SO3 film. The role of plasticizer is to increase the rate of ion dissociation, hence the conductivity of the sample increased. The conductivity of the highest conducting sample of plasticized ENR-50 + 35 wt%, was 2.28 x 10-4 S cm-1. Finally, lithium-air cell using gelled polymer electrolytes was fabricated and characterized. The lithium-air showed a large capacity of 1134 mAhg-1 at discharge current of 1.0 raA
Performance of 4KWp Grid-Connected Photovoltaic (GCPV) system using micro-inverter technology for residential application / Nazreen Baharuddin, Sulaiman Shaari and Nurmalessa Muhammad
Get PDFEven though the cost of a grid-connected photovoltaic (GCPV) system has decreased significantly as a result of widespread commercial acceptance, current technologies are continually improved to reduce cost and increase efficiency. By contrast, relatively recent technologies such as maximizers and micro-inverters seek to encourage new techniques of solar energy production at a reasonable cost. While micro-inverters are gaining popularity in the solar industry, industry claims of improved system performance remain unproven. Third-party validation is critical for assessing the efficiency of micro-inverter technology. The objective of this research is to analyze the service provider's reported yearly availability performance for a 4kWp residential grid-connected photovoltaic (GCPV) system with micro-inverter technology located in Shah Alam, Malaysia, as well as gauging the owner's satisfaction with the system. The actual data for the years 2017, 2019, and 2020 were analyzed to determine the annual specific yield (SYmea) and performance ratio (PRmea). The results show that the actual annual SYmea varies between 1,144 kWh kWp-1 and 1,196 kWh kWp-1, while the PRmea for the system ranges from 0.729 to 0.762. This research presents actual data to support the conclusion that the system is underperforming, resulting in a dissatisfied system owner since the PRmea for 2019 and 2020 falls short of the GCPV PR requirement as announced by Sustainable Energy Development Authority (SEDA) Malaysia
System performance and detectable faults of a 10-year old 1.1 kWp GCPV system in Malaysia / Nurmalessa Muhammad ... [et al.].
Get PDFThis paper presents the findings of a study conducted to evaluate the performance and to identify faults of a 10-year old 1.1kW grid-connected photovoltaic (GCPV) system installed at Green Energy Research Center (GERC), Universiti Teknologi MARA (UiTM), Shah Alam. The system performance was evaluated by comparing the real operating field data with the data declared by the manufacturer. Eight performance indicators were used, which are: reference yield, array yield, final yield, capture losses, system losses, performance ratio, PV array efficiency and total efficiency. The fault detection has used three techniques - which were visual inspection as outlined in the International Energy Agency (IEA) document, thermal imager technique and the I-V curve characteristics. The finding for the system performance evaluation gives a 13.2% difference between the real operating field data and the declared manufacturer data. Among the
faults detected from the visual inspection are browning and cracks of PV modules
Threshold value of DC array current and DC string voltage for fault detection in grid-connected photovoltaic system / Nurmalessa Muhammad … [et al.]
Get PDFThe failure detection in a grid-connected photovoltaic (PV) system has become an important aspect of solving the issue of the reduced energy output in the PV system. One of the methods in detecting failure is by using the threshold-based method to compute the ratio of actual and predicted DC array current and DC string voltage value. This value will be applied in the failure detection algorithm by using power loss analysis and may reduce the time, cost and labour needed to measure the quality of the energy output of the PV system. This study presented the threshold value of DC array current and DC string voltage to be implemented in the algorithm of fault detection in grid-connected photovoltaic (PV) system under the Malaysian climate. Data from the PV system located at Green Energy Research Center (GERC) was recorded in 12 months interval using the monocrystalline PV modules. The actual data was recorded using five minutes interval for 30 consecutive days. The prediction of the data was calculated using the mathematical method. The threshold value was determined from the ratio between actual and predicted data. The results show that the DC array current threshold value, σ is 0.9816. While, DC string voltage threshold value, λ is 0.9261. The proposed value may be beneficial for the determination of threshold value for regions with the tropical climate
System performance and detectable faults of a 10-year old 1.1 kWp GCPV system in Malaysia
No full textThis paper presents the findings of a study conducted to evaluate the performance and to identify faults of a 10-year old 1.1kW grid-connected photovoltaic (GCPV) system installed at Green Energy Research Center (GERC), Universiti Teknologi MARA (UiTM), Shah Alam. The system performance was evaluated by comparing the real operating field data with the data declared by the manufacturer. Eight performance indicators were used, which are: reference yield, array yield, final yield, capture losses, system losses, performance ratio, PV array efficiency and total efficiency. The fault detection has used three techniques - which were visual inspection as outlined in the International Energy Agency (IEA) document, thermal imager technique and the I-V curve characteristics. The finding for the system performance evaluation gives a 13.2% difference between the real operating field data and the declared manufacturer data. Among the faults detected from the visual inspection are browning and cracks of PV modules
Threshold value of DC array current and DC string voltage for fault detection in grid-connected photovoltaic system
No full textThe failure detection in a grid-connected photovoltaic (PV) system has become an important aspect of solving the issue of the reduced energy output in the PV system. One of the methods in detecting failure is by using the threshold-based method to compute the ratio of actual and predicted DC array current and DC string voltage value. This value will be applied in the failure detection algorithm by using power loss analysis and may reduce the time, cost and labour needed to measure the quality of the energy output of the PV system. This study presented the threshold value of DC array current and DC string voltage to be implemented in the algorithm of fault detection in grid-connected photovoltaic (PV) system under the Malaysian climate. Data from the PV system located at Green Energy Research Center (GERC) was recorded in 12 months interval using the monocrystalline PV modules. The actual data was recorded using five minutes interval for 30 consecutive days. The prediction of the data was calculated using the mathematical method. The threshold value was determined from the ratio between actual and predicted data. The results show that the DC array current threshold value, ? is 0.9816. While, DC string voltage threshold value, ? is 0.9261. The proposed value may be beneficial for the determination of threshold value for regions with the tropical climate
Fault detection using acceptance ratio analysis on polycrystalline grid-connected photovoltaics syste
Get PDFAround the world, electricity generation from PV photovoltaic systems is increasing, achieving 10-20% PV system efficiency. However, PV systems degrade due to the technology and the operating conditions and become worse in tropical climate countries. Hence, degradation is one of the key performance indicators for the reliability assessment of a PV system. This paper presents the acceptance ratio (AR) analysis grid-connected photovoltaic (GCPV) located on the campus of the Universiti Teknologi MARA, Shah Alam, Malaysia as the key performance indicators. A comparative analysis of the actual and predicted AC Power and AR of the polycrystalline GCPV system is carried out over monitoring of a one-year period. MATLAB software is chosen to simulate the output power using actual data. Malaysian Standard MS2692:2020 has noted that the AR value must ≥ 0.9 to classify as accepted in testing and commissioning tests and AR < 0.9 has been indicated as a non-accepted GCPV system. The results of acceptance ratio (AR), yield (Y), specific yield (SY), and performance ratio (PR) show that almost half of the AR’s data results show below 0.9 with the performance ratio of PV systems was less than 75%, indicating that the systems needed to be completely replaced
Simulation and prediction of residential grid-connected photovoltaic system performance
Get PDFThis paper presents the analysis of the actual, predicted, and simulated technical performance of a residential 2.835 kWp retrofitted grid-connected photovoltaic (GCPV) system under the feed-in-tariff (FiT) scheme in Klang, Malaysia located in the equatorial region. The technical performance indices of the GCPV system were assessed based on the three-year energy production in 2018, 2019 and 2020. The actual and predicted technical performance were calculated using SEDA mathematical model, which the solar irradiation data was acquired from PVsyst software. Meanwhile, the simulated technical performance was obtained using PVsyst software. The results showed that the prediction using mathematical model has higher percentage difference within the range of 12.54%-13.29%, compared to PVsyst simulation that was within 7.93%-11.93%. This study has highlighted the factors that contributed to the technical performance underprediction of both mathematical model and PVsyst simulation, which are the estimation of losses and annual irradiation data accuracy. Lastly, the annual FiT gross income calculated for the three consecutive years were within the range of 3310.80 MYR and 3357.30 MYR. This FiT gross income result conveys an example of Malaysian case study, to enlighten the public, on the economic aspect of installing GCPV system under FiT scheme
