توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Standstill and low speed sensorless control of SMPMSM by using digital FIR filter in the HF signal injection method
اطلاعات انتشار: نوزدهمین کنفرانس مهندسی برق ایران، سال
تعداد صفحات: ۶
In this paper a sensorless speed vector control method at standstill and low speed in the Surface Mount Permanent Magnet Synchronous Motor (SMPMSM) drive system is described. A high–frequency model of an SMPMSM in the rotor reference frame is developed based on a sensorless rotor speed estimation algorithm. Furthermore, a digital filter is used to reduce the delay effect of conventional analog filters. The coefficients of the digital filter are optimized by using Genetic Algorithm (GA). Also the speed and current PI controllers which are used in the vector control scheme are adjusted based on GA. Simulation results for a 370 V 2.8 Kw,1500rpm SMPMSM confirm the good performances of the proposed method in standstill and low speed cases<\div>

۲The Effect of Nanofluid Containing Functionalized Carbon Nanostructures on Heat Recovery of a Two Phase Closed Thermosyphon
اطلاعات انتشار: دومین کنفرانس بین المللی رویکردهای نوین در نگهداشت انرژی، سال
تعداد صفحات: ۷
In this study, thermal performance of a Two–Phase Closed Thermosyphon (TPCT) was investigated by adding of functionalized Multi–wall carbon nanotubes (f– MWCNT) with the silver in pure water. The experiments were performed in a TPCT of 45 cm length and outside diameter of 2 cm, in input powers of 30 – 90 W and weight fraction of 0.5% and 1%. Experimental results indicate that an increase in input power leads to an increase in thermal efficiency. In addition, increasing the weight fraction of nanofluid may increase thermal efficiency of TPCT. The results also reported that improved average overall heat transfer coefficient of TPCT might increase input power and weight fraction of nanofluid. However, the highest thermal efficiency and the average overall heat transfer coefficient of TPCT occurred in about 95.8% and 373 kW\m2°C respectively in power of 90 W.<\div>

۳MODELING OF HEAT TRANSFER CHARACTERIZATION OF A TWO–PHASE CLOSED THERMOSYPHON USING MWCNT\WATER AND MWCNT–AG\WATER NANOFLUIDS
اطلاعات انتشار: پانزدهمین کنفرانس دینامیک شاره ها (سیالات)، سال
تعداد صفحات: ۱۰
Here, first a two–phase closed thermosyphon (TPCT) was designed and then two samples of multi–walled carbon nanotube (MWCNT) and MWCNT functionalized with Ag were synthesized. To obtain experimental data, the effect of various samples synthesized on thermal efficiency and resistance was studied. Then, to expand experimental data and predict optimal conditions, modeling was performed by Adaptive Neuro–Fuzzy Inference System (ANFIS). Experimental and predicted data were compared to inspect the accuracy of the model. Validation of ANFIS results were confirmed by five arithmetical criterions (R2, MSE, MAE, ARE and AARE). As more consideration, three–dimensional diagrams of the model were drawn to realize optimal range of concentration and input power as well as the type of nanofluid.<\div>
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