Brushless DC Fan Research Articles

Novel design and performance evaluation of an indirectly forced convection desiccant integrated solar dryer for drying tomatoes in Pakistan

The process of drying agricultural products for food preservation is a difficult task that requires a significant amount of energy. The increasing cost and depletion of fossil fuels have led to the development of a food dryer that utilizes renewable energy sources. This research paper proposes the design and performance evaluation of an indirectly forced convection desiccant integrated solar dryer (IFCDISD) at the Solar Energy Research Lab at USPCAS-E, NUST Pakistan. Tomatoes were chosen as the test product due to their importance and widespread consumption. The drying process involves slicing the tomatoes and placing them on the IFCDISD rack, where a desiccant called calcium chloride (CaCl2) is integrated into the dryer. The experiments were conducted during both sunshine (SS) hours and Off-sunshine (OSS) hours. The IFCDISD operates using sunlight during SS hours and utilizes the absorbed heat of CaCl2 in OSS hours via a forced DC brushless fan powered by battery charged thro solar panel. The tomatoes were weighed before and after each drying mode, and the moisture removal was calculated. The results show that the dryer efficiency was 50.14 % on day 1, 66 % on day 2, and an overall efficiency of 58.07 %. The moisture content removal was 42.858 % on day 1, 22.9979 % on day 2, and an overall moisture content removal of 58.07 %. Moreover, the payback period is 5.1396 and the carbon mitigation was recorded as 2.0335, and the earned carbon credit was recorded as 11559.6.

Facile synthesis of a three-dimensional Ln-MOF@FCNT composite for the fabrication of a symmetric supercapacitor device with ultra-high energy density: overcoming the energy storage barrier.

In order to quench the thirst for efficient energy storage devices, a novel praseodymium-based state-of-the-art three-dimensional metal-organic framework (MOF), {[Pr(pdc)2]Me2NH2}n (YK-1), has been synthesized by using a simple solvothermal method employing a readily available ligand. YK-1 was characterised by single-crystal XRD and crystallographic analysis. The electrochemical measurements of YK-1 show that it exhibits a specific capacitance of 363.5 F g-1 at a current density of 1.5 A g-1 with 83.8% retention after 5000 cycles. In order to enhance its electrochemical performance for practical application, two composites of YK-1 with graphene oxide (GO) and functionalised multi-walled carbon nanotubes (FCNTs), namely YK-1@GO and YK-1@FCNT, were fabricated by employing a facile ultrasonication technique. The as-synthesized MOF and the composites were characterized by PXRD, FTIR, SEM, and TEM techniques. YK-1@GO and YK-1@FCNT offer enhanced specific capacitances of 488.2 F g-1 and 730.2 F g-1 at the same current density with 93.8% and 97.7% capacity retention after 5000 cycles, respectively (at 16 A g-1). Fascinated by the outstanding results shown by YK-1@FCNT, a symmetric supercapacitor device (SSC) based on it was fabricated. The assembled SSC achieved a remarkable energy density (87.6 W h kg-1) and power density (750.2 W kg-1) at a current density of 1 A g-1, along with very good cycling stability of 91.4% even after 5000 GCD cycles. The SSC device was able to power up several LED lights and even operated a DC brushless fan for a significant amount of time. To the best of our knowledge, the assembled SSC device exhibits the highest energy density among the MOF composite-based SSCs reported so far.

Performance assessment of PVT-air collector with V-groove absorber: A theoretical and experimental analysis

In this paper, the performance of a PVT (photovoltaic thermal) air collector with V-groove absorber in the air channel is theoretically and experimentally examined under different climate conditions of Ghaziabad city, India, in summer, June 2019. A low power brushless DC fan is fixed at the input of the air-channel to ensure the circulation of air through the V-groove. The energy balance equation is developed with the matrix-inversion method to estimate the PV (photovoltaic) cell and air output temperatures. The theoretical results obtained using mathematical modeling has been compared with that of the real-time experimental results. The electrical, thermal, and overall efficiencies for the theoretical and experimental studies are found in the range of 10.39–10.26%, 41.78–41.57%, and 52.17–51.81%, respectively. It has been observed that the theoretical results are coherent with experimental results for the proposed model achieving an accuracy of 98.98%, 99.43%, and 99.31% for electrical, thermal, and overall efficiencies, respectively.

An Initial States Recognition (ISR) Method for Start-Up of 1Ф BLDC Motor in Hall-Sensor-Less Fan Applications

The initial state is very important for a single-phase brushless DC (BLDC) fan motor when starting, especially in fan application with a nonstatic motor. The direction of self-rotation caused by the external thrust needs to be considered to avoid the starting fail or wrong running direction. This article proposes an initial states recognition (ISR) method to smartize the starting procedure. However, the self-rotation direction identification of single-phase BLDC motors is a challenge, which is even more difficult in some applications without rotor position sensors. The unequal air gap, which is designed by the geometric variation on the pole shoe to form the asymmetric stator, is generally the necessary design for the single-phase BLDC motor to dodge the null torque position (dead point) and determine the operation direction; and it will further form the asymmetrical waveform of the back electromotive force (EMF) voltage. The asymmetric distribution of back EMF waveform will be opposite in half cycle (positive or negative half cycle) with the rotation direction. The proposed ISR method utilizes this trait to achieve the self-rotation direction recognition before starting a dynamic single-phase BLDC fan motor. Finally, under the architecture of Hall-sensor-less control, the experimental results prove that the proposed method is reliable and feasible.

Design of Temperature Control Coolant

Design of Temperature Control Coolant

Comparison between DC Brushless Fan and DC Hybrid Solar Panel Cooling System

The purpose of this paper is compare between DC brushless fan and DC hybrid solar panel cooling system. The efficiency of PV module is depending on solar irradiance and ambient temperature. As temperature of PV module increase, the output current will increase but output voltage and output power will decrease and also vice versa. As solar irradiance increase, output current and output power will increase with linear and output voltage will increase with marginal and vice versa. The DC cooling system is a way to fix the issue of low efficiency of PV module with the intention to generate more electrical energy. To make an attempt to cool down the PV module, DC brushless fan and water pump with inlet/outlet manifold are built for constant fresh air movement and water flow circulation at the backside and front surface of PV module. The PV module with DC brushless fan cooling system increase 3.47 %, 29.55 %, 32.23 % in term of output voltage, output current, and output power respectively. It decrease 6.1 °C compare than to PV module without DC brushless fan cooling system. While PV module with DC hybrid cooling system increase 4.99 %, 39.90 %, 42.65 % in term of output voltage, output current, and output power respectively. It decrease 6.79 °C compare to PV module without DC hybrid cooling system. The efficiency of PV module with cooling system was increasing compared to PV module without cooling system, for the reason that the ambient temperature dropped significantly. An increase in efficiency of PV module, investment payback period of the system can reduce and the lifespan of PV module will be prolonged.

Comparative Efficiency of Solar Panel by Utilize DC Water Pump and DC Hybrid Cooling System

The purpose of this paper is discussed about comparative efficiency of solar panel by utilize DC water pump and DC hybrid cooling system. Ambient temperature and solar irradiance are played main role of the efficiency of PV module. When temperature of PV module increase, the efficiency of PV module will decreased and vice versa. When solar irradiance increase, output current and output power will increase with linear and output voltage will increase with marginal and vice versa. A solution is provided to solve problem of low efficiency of PV module which is DC cooling system. DC brushless fan and water pump with inlet/outlet manifold were designed for actively cool the PV module to improve efficiency of PV cells. The PV module with DC water pump cooling system increase 3.52 %, 36.27 %, 38.98 % in term of output voltage, output current, and output power respectively. It decrease 6.36 °C compare than to PV module without DC water pump cooling system. While PV module with DC hybrid cooling system increase 4.99 %, 39.90 %, 42.65 % in term of output voltage, output current, and output power respectively. It decrease 6.79 °C compare to PV module without DC water pump cooling system. The higher efficiency of PV module, the payback period of the system can be shorted and the lifespan of PV module can be longer.

Comparison of solar panel cooling system by using dc brushless fan and dc water

The purpose of this article is to discuss comparison of solar panel cooling system by using DC brushless fan and DC water pump. Solar photovoltaic (PV) power generation is an interesting technique to reduce non-renewable energy consumption and as a renewable energy. The temperature of PV modules increases when it absorbs solar radiation, causing a decrease in efficiency. A solar cooling system is design, construct and experimentally researched within this work. To make an effort to cool the PV module, Direct Current (DC) brushless fan and DC water pump with inlet/outlet manifold are designed for constant air movement and water flow circulation at the back side and front side of PV module representatively. Temperature sensors were installed on the PV module to detect temperature of PV. PIC microcontroller was used to control the DC brushless fan and water pump for switch ON or OFF depend on the temperature of PV module automatically. The performance with and without cooling system are shown in this experiment. The PV module with DC water pump cooling system increase 3.52%, 36.27%, 38.98%in term of output voltage, output current, output power respectively. It decrease 6.36 °C compare than to PV module without DC water pump cooling system. While DC brushless fan cooling system increase 3.47%, 29.55%, 32.23%in term of output voltage, output current, and output power respectively. It decrease 6.1 °C compare than to PV module without DC brushless fan cooling system. The efficiency of PV module with cooling system was increasing compared to PV module without cooling system; this is because the ambient temperature dropped significantly. The higher efficiency of PV cell, the payback period of the system can be shorted and the lifespan of PV module can also be longer.

THERMOELECTRIC POWER GENERATOR INTEGRATED COOKSTOVE: A SUSTAINABLE APPROACH OF WASTE HEAT TO ENERGY CONVERSION

A prototype is developed for thermoelectric power generator module integrated with a double chambered forced draft cookstove. A module of an appropriate rating is chosen for the testing and then power generation is observed. The voltage generated is further stepped-up using a DC-DC step-up converter to run a DC brushless fan of 5V, 0.3A. The fan serves two tasks, first is to cool the one side of thermoelectric power generator and second is to supply the air to the combustion chamber of cookstove. The air is directed to the combustion chamber through a duct which increases the air-to-fuel ratio which helps for a cleaner combustion. A net output of 4W is generated from the thermoelectric power generator.

Improvement on ESD Protection of Output Driver in DC Brushless Fan ICs by the FOD Protection Block

In this paper, ESD improvements of an output driver that driving a large current in DC brushless fan ICs under HBM ESD stress is investigated. In order to improve ESD robustness, some protection blocks will be designed and implemented by the layout parameters and structures tuning. From the preliminary ESD testing result, it was found that the positive Pad-to-VSS (PS) zapping mode of the original DUT is weakest for the output driver of DC brushless fan ICs during an HBM zapping. After a systematic improvement, it is found that the FOD structure of adding protection circuits can effectively protect the whole-chip ESD damage, as compared with the original DUT; the values of ESD failure threshold (VESD) are increased > 57%, which allows output driver devices more robust in the ESD immunity.

Implementation of ESD Protection for Output Driver ICs with SCR Circuits Techniques

In this paper, an output driver which drove a large current in DC brushless fan ICs was taken for the HBM ESD stress. The protection circuits of this IC were also designed to improve ESD robustness by various layout parameters and structures. From the ESD testing results, it was found that the positive Pad-to-VSS (PS) zapping mode was weakest for the output driver of DC brushless fan ICs during ESD stress. Eventually, protection circuits with a complementary low-voltage-triggered SCR (LVTSCR) were used to protect the whole-chip ESD stress. After a systematic improvement, an SCR structure of adding protection circuits can effectively protect the whole-chip ESD reliability, as compared with the original DUT; the ESD failure threshold (VESD) of PS mode is increased 314% in a best structure when an LVTSCR with the drain-tap S space is 4μm.

A Driver for the Single-Phase Brushless DC Fan Motor With Hybrid Winding Structure

This paper mainly proposes a novel driver for a single-phase brushless dc fan motor with a hybrid series/parallel winding structure. The winding symbols and directions of the hybrid motor stator structure are defined, and the winding steps for the proposed series/parallel winding are explained. An adequate inverter driving circuit, which is capable to simultaneously obtain the advantages of the hybrid structure, is also discussed. At last, the overall system of this hybrid brushless dc motor with the proposed driving circuit is then implemented to verify the performance of the proposed driver and structure.

The Study of Prognostics and Health Management for the Air Cooling Equipments Based on FMA and Life Test

The demands of Prognostics and Health Management (PHM) for the air cooling equipment are constantly growing in the industrial field. However, most studies on PHM of fans are still in the exploratory stage, the failure modes and working conditions are mostly single and ideal. It proposed a PHM method for the brushless DC fan. Firstly it makes an analysis on the failure mode of the air cooling equipment. Secondly, two kinds of the prognostic tests are made, including fault simulation test and accelerated life test. After that, a prognostics method based-on the combination of reliability and data-driven models are proposed. The test results show that the proposed prediction method has a strong practical value.

A New Technique of Photovoltaic/Wind Hybrid System in Perlis

The increment of energy costs and decreasing prices of turbines generator and photovoltaic (PV) panels caused photovoltaic/wind hybrid system (PWHS) utilization is becoming popular. This paper presents a new topology of PWHS. It is consists of two main parts: the cooling system for photovoltaic module and the combination method of Savonius and Darrieus for wind turbine. The PWHS is installed in front of Centre of Excellence for Renewable Energy (CERE), University Malaysia Perlis, Northern Malaysia. The main energy source of this system is gain from PV array and wind power generation. It is well known that the power and efficiency of photovoltaic (PV) module usually falls at the rate of ∼0.5%/°C and ∼0.05%/°C respectively as increase of ambient temperature. The electrical efficiency of PV cell depends on its operating temperature during absorption of solar radiation. For this reason, an active PV cooling system was design using the DC brushless fan with inlet/outlet manifold for uniform airflow distribution. It was attached at the back of the PV panel. Where else, the improvement of wind is using Vertical Axis Hybrid Wind Turbine (VAWT) through the combination method of Savonius and Darrieus types. From the results, it shows that the improvement of PWHS give the big advantages in term of supply the energy in Perlis.

Optimizing Efficiency Driver Comprising Phase-Locked Loop for the Single-Phase Brushless DC Fan Motor

Because the single-phase brushless fan motor presents an inductive load, the winding current will lag the back-electromotive force (EMF) an unequal phase based on the different motor speed. In order to improve the efficiency and torque performance, adjusting the commutation angle to keep the optimizing commutation at different speed is necessary. In this paper, the new structure with low cost to achieve the optimizing commutation is accomplished by the concept of phase-locked loop (PLL) to synchronize the winding current and back EMF. The PLL IC CD4046 is adopted to develop a feedback circuit and performs the function of phase advance. The purpose is to force the winding current to be synchronized with the back-EMF. Finally, the related experimental results are used to confirm the feasibility and effectiveness of the proposed driving method.

Axial Vibration Study of a Mobile Fan Motor

A method observing both radial and axial vibrations of time domain and frequency spectrum was studied to investigate the axial load effect of a flat-type brushless dc fan motor operating with and without the rated axial thrust force. When the developed small motor does not exhibit an intrinsically excited unbalanced magnetic force (UMF), the axial force leads to a minor contribution to the growth of the axial vibration. However, when the UMF is intrinsically excited, the preload can enormously decrease the undesired axial vibration. The ratio of the axial vibration of the prototype with the asymmetric magnetic sheet to the one without the sheet is experimentally observed around 55 percent. It demonstrates that axial load plays an effective and crucial factor in controlling the axial vibration of the mobile fan motor.

Optimal Driving Efficiency Design for the Single-Phase Brushless DC Fan Motor

One of the methods to improve efficiency and torque performance of the single-phase brushless DC (BLDC) motor is to find out the optimum commutation angle at each different speed. We used the finite-element method (FEM) to simulate the back-EMF voltage and the coil current for the single-phase BLDC motor, and then adjust the conduction time of switches by detecting the waveform of coil current. The motor can improve its efficiency, noise, and vibration when it obtains the optimal shift angle of each speed. We used PSPICE to verify the exactness of FEM simulation results of the single-phase BLDC motor. We adopted Microchip's dsPIC30F4011 digital signal processor (DSP) to process the Hall signal and the driving signals of switches of the driving system prototype of the single-phase BLDC fan motor. Finally, we used the related experimental results to confirm the feasibility and effectiveness of the proposed driver.