Current Issue : January-March Volume : 2023 Issue Number : 1 Articles : 5 Articles
Prediction of available energy storage power is essential for increasing the energy management performance of fuel cell hybrid electric systems (FCHES). A simple yet effective power prediction index is proposed to estimate the supercapacitor state of power. It prevents the supercapacitor’s total depletion in the battery/supercapacitor combination. Modern energy management is equipped with an equivalent consumption minimization strategy. The power prediction index is simple compared with other predictive algorithms while providing excellent efficiency compared with supercapacitor-based management strategies. A supercapacitor-based strategy is presented which extends battery life, at the cost of increased fuel consumption. However, it cannot predict the future low state of charge for the supercapacitor. In such conditions, the battery provides the demand power while fuel cells generate more current. On the other hand, the modern power prediction index energy management strategy significantly increases battery life without adding extra hardware. Moreover, fuel consumption decreased by 15.1 percent. The results show that the modern energy management strategy provides outstanding performance for battery life and fuel consumption compared with other energy management strategies due to its power limitation prediction....
The purpose of this study was to investigate the electrical properties of pressboard impregnated with mineral oil-based nanomaterial. The nanomaterial focused on in this study was magnetite (Fe3O4) at ratios of 0.01%, 0.03%, and 0.05% by mineral oil volume. The electrical tests were performed on the AC breakdown strengths and positive-negative lightning impulse breakdown strengths on impregnated pressboard were carried out in compliance with IEC 60641 and IEC 60243, respectively. Scanning electron microscopy (SEM) and X-ray Diffraction (X-RD) were used to study the micro surface and show that Fe3O4 nanoparticles of nanoscale size were adhered to the pressboard surface and exist in an amorphous state. The results found that the AC breakdown strengths of pressboard impregnated with mineral oil-based Fe3O4 nanofluids at 0.03 wt% were increased the most. Moreover, the lightning impulse breakdown strengths of pressboard impregnated with mineral oil-based Fe3O4 nanofluids at 0.03 wt% were increased the most in both positive and negative polarities. The results, thus, showed promising directions for applications of Fe3O4 nanomaterials to improve the electrical properties of pressboard....
Pipelines are typically used to transport oil, natural gas, water, etc. It is one of the most effective methods for transferring fluids over long distances. However, long-term usage of these pipes without maintenance results in the formation of residues, which will pave the way for pipeline accidents and soil contamination. To ensure the safety and protection of resources, these sustainable pipelines need to be inspected to avoid losses. This work aims to investigate various internal defect leaks in the non-uniform thickness of sustainable water pipes that are joined with a pipe expander. The magnetic flux leakage technique was implemented to evaluate these defects by means of a flexible GMR sensor array. An inspection robot containing two units was fabricated with the aid of 3D printing. The power unit provides the necessary thrust to actuate the entire robot whereas the sensing unit is responsible for analyzing the leaks. The robot’s movement is predicted by the MPU6050 and ultrasonic distance sensors that are plotted as motion plots. The sensing unit consists of permanent magnets and a giant magnetoresistance (GMR) array to interrogate the flux leakage in the defect region. The flux leakage from the defects was stored with the help of an Arduino microcontroller, which controls the overall process. In addition, the spring suspension is provided to regulate the motion of the robot. The flux leakage from the defect region was plotted as waveform graphs. Thus, the results are effectively presented and compared. The calculated signal-to-noise ratio (SNR) of the magnetic flux leakages (MFLs) for 4.5 mm-thick pipe defects was 12 to 20.8 dB, and for 6.52 mm-thick pipe defects, it was 9.5 to 19 dB. In sum, the MFL technique provides a reliable method for the sustainable development of water supply to wide areas....
This paper shows a model of a five-phase synchronous motor with permanent magnets and a simulation model of a control device. A simulation model in the SimInTech software product is built. The transient time is 0.03 s when a stepped input is applied. When the load moment of inertia increases by a factor of 10, the accuracy of speed response decreases. The maximum motor speed error is 40% at a time of 0.2 s. This is a consequence of changing the model of the control object. It is suggested to perform model identification and adapt PI controllers according to load parameters....
Power system stability is a very important issue in power system engineering because a decrease in the stability margins can cause unacceptable operating conditions, which leads to frequent failures. In this paper, SKM POWER TOOLS PTW-32 Version 4.5.2.0 was used to study different Stability recovery tests after a medium voltage short circuit fault on a turbine generator in the power system. The analysis focused on the generator electrical and mechanical powers stability recovery test, generator speed stability recovery test, excitation voltage stability recovery test, bus voltage and bus frequency stability recovery test. In our study, when the introduced fault was cleared after 0.5 s, it reveals that the recovery rate of electrical power was much faster than that of mechanical power. Also, the results reveal that it took about 10 seconds for the turbine speed to stabilize while it took fewer seconds for the frequency to stabilize....
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