List of Articles مجید دهقانی

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  1 - Investigating the Effect of Parameters on the Dynamic Behavior of Permanent Magnet Stepper Motor Using State Space Analysis
  Ghazanfar Shahgholian Majid Dehghani Majid Moazzami
  20.1001.1.25887327.2022.6.3.5.5
  Stepping motors are normally operated without feedback and may suffer from loss of synchroni-zation. The permanent magnet stepper motor (PMSM) is generally two-phase. In this paper, the nonlinear dynamic equations governing the performance of the permanent magnet steppe More

  Stepping motors are normally operated without feedback and may suffer from loss of synchroni-zation. The permanent magnet stepper motor (PMSM) is generally two-phase. In this paper, the nonlinear dynamic equations governing the performance of the permanent magnet stepper motor are linearized at an operating point for small signal stability studies. Small signal stability is the system ability to maintain synchronism when a small disturbance occurs. It is based on the state space averaging approach. A detailed description of the method, results, and conclusions are also presented. Finally, simulation results for three motors have been reported and compared Manuscript profile
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  2 - Analysis and Simulation Dynamic Behavior of Power System Equipped with PSS and Excitation System Stabilizer
  Arman Fattollahi Majid Dehghani Mohamad Reza Yousefi
  20.1001.1.25887327.2022.6.1.6.2
  Power system is a nonlinear and temporal variable system. Different parts of the system change at different times and times with changing loads or loss of generators and disturbances. Power system stability and attenuation of low frequency fluctuations are very importan More

  Power system is a nonlinear and temporal variable system. Different parts of the system change at different times and times with changing loads or loss of generators and disturbances. Power system stability and attenuation of low frequency fluctuations are very important. To increase the damping power and stability of the dynamic system, power system stabilizers are used to reduce fluctuations by generating additional control signals for the generator excitation system. In this paper, to improve the stability of the power system dynamic, a power system stabilizer based on synergistic control theory with an excitation system stabilizer according to a simplified nonlinear power system is used. The power system stabilizer has been studied in a single machine system connected to an infinite bus. The results show that the use of power system stabilizer and excita-tion system stabilizer for all nonlinear dynamic systems performs better than synergistic PSS, conventional PSS, and a system without stabilizer. Manuscript profile
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  3 - Design and Implementation a Single-Phase UPS Based on Microcontroller with AVR at Input and Full-Bridge Inverter at Output for Improving Sinusoidal Output Voltage
  Ahmad Omrani Majid Dehghani Mohamad Reza Yousefi
  20.1001.1.25887327.2021.5.4.4.9
  In this paper, a novel application that uses the broadband noise from a ship-of-opportunity to estimate the scattering from underwater objects is reported. The propagation is based on the normal-mode model. The source localization (location of propeller) is initially re More

  In this paper, a novel application that uses the broadband noise from a ship-of-opportunity to estimate the scattering from underwater objects is reported. The propagation is based on the normal-mode model. The source localization (location of propeller) is initially realized using incoherent broadband matched-field processing. Then, by utilizing an estimator that relies on Normal-Modes, the target echo below the sea surface is calculated to evaluate the location of the target. The proposed idea is illustrated using simulation and then verified using the acoustic data from a 2019 underwater communication trial in Grand Passage, Nova Scotia in Canada. Experimental results show that the proposed technique can be a reliable signaling method and environmentally friendly that can be applied to the fields of underwater communication and ocean monitoring for a shallow water environment. Manuscript profile
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  4 - Switching Pattern for Transformer Cascaded Inverter in Dynamic Voltage Restorer Structure
  Shirin Soltani Majid Dehghani Majid Moazzami
  20.1001.1.25887327.2021.5.3.4.7
  Sensitive loads cannot tolerate voltage sags and swells in power distribution networks and lots of problems are engendered for them. Therefore, dif f e rent instruments are pla nn ed to compensate volt a ge swells and sags. Between them dynamic voltage restorer (DVR) h More

  Sensitive loads cannot tolerate voltage sags and swells in power distribution networks and lots of problems are engendered for them. Therefore, dif f e rent instruments are pla nn ed to compensate volt a ge swells and sags. Between them dynamic voltage restorer (DVR) has found special import a n c e, because it operates better than others for this purpose and restores voltage to its initial value conveniently. A DVR is a power-electronic controller that can protect sensitive loads from disturbances in the supply system. The DVR is installed in series to the network. In this paper 9 level cascaded inverters with cas ca d ed transfor m e r s are used in DVR internal circuit, but the difference in magnetic flux in cascading transformers has adverse effects on the plan. Therefore, a new switching pattern is used Manuscript profile
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  5 - Electronic Ballast Design for Fluorescent Lamps with High Power Factor
  Omid Sharifiyana Majid Dehghani Ghazanfar Shahgholian Sayyed Mohammad Mehdi Mirtalaei Masoud Jabbari
  20.1001.1.25887327.2023.7.1.2.5
  Fluorescent lamps are used as one of the most important sources of light in residential and commercial applications. A method to increase the power factor in electronic ballasts is proposed in this paper. For the power factor correction circuit, the amplification-based More

  Fluorescent lamps are used as one of the most important sources of light in residential and commercial applications. A method to increase the power factor in electronic ballasts is proposed in this paper. For the power factor correction circuit, the amplification-based switching method is used, which increases the power factor and provides the DC voltage for starting the half-bridge inverter circuit. Finally, the laboratory sample of the circuit is made at a voltage of 110 V with a power factor of 0.996. This circuit has an efficiency of 94.7% and a total harmonic distortion less than 5%. In addition, the pressure on the lamp at the moment of commissioning is reduced, which increases the life of the lamp. Manuscript profile