A Low-Cost High-Efficiency CCFL Inverter With New Capacitive Sensing and Control

2006 ◽  
Vol 21 (5) ◽  
pp. 1444-1451 ◽  
Author(s):  
S.K. Kim ◽  
H.S. Han ◽  
Y.J. Woo ◽  
G.H. Cho
Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 634 ◽  
Author(s):  
Yang Li ◽  
Zongxia Jiao ◽  
Zimeng Wang

In order to provide a simplified and low-cost solution of the terminal for a distributed actuation system, this paper proposes an electro-hydrostatic actuator (EHA) based on the linear drive principle. The proposed actuator is directly driven by a linear pump with a collaborative rectification mechanism, whose performance relies on the collaboration of the internal two units. A pair of linear oscillating motors are employed to drive the two pump units respectively. The control of the actuator is based on the modulation of the oscillating amplitude, frequency, and phase difference of the two motors. The advantage of this actuator is that no more valve control is needed to rectify the linear pump besides the high efficiency of the direct pump drive. In this paper, both schematic and detailed structure of the actuator is presented. The kinematic and dynamic characteristics are analyzed and modeled, based on which the control method is proposed. The experiments verify the validity of the actuator structure and control.


2020 ◽  
Author(s):  
Karina Rossi da Silva ◽  
William Ribeiro da Silva ◽  
Bianca Piraccini Silva ◽  
Adriano Nobre Arcos ◽  
Francisco A. da Silva Ferreira ◽  
...  

AbstractThe control of arboviruses carried by Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) can be performed with tools that monitor and reduce the circulation of these vectors. Therefore, the efficiency of four types of traps in capturing A. aegypti and A. albopictus eggs and adults, with the biological product Vectobac WG®, was evaluated in the field. For this, 20 traps were installed in two locations, which were in the South (Londrina, Paraná) and North (Manaus, Amazonas) Regions of Brazil, from March to April 2017 and January to February 2018, respectively. The UELtrap-E and UELtrap-EA traps captured A. aegypti and A. albopictus eggs: 1703/1866 eggs in Londrina, and 10268/2149 eggs in Manaus, respectively, and presented high ovitraps positivity index (OPI) values (averages: 100%/100% in Londrina, and 100%/96% in Manaus, respectively); and high egg density index (EDI) values (averages: 68/75 in Londrina, and 411/89 in Manaus, respectively), so they had statistically superior efficiency to that of the CRtrap-E and CRtrap-EA traps in both regions, that captured less eggs and adults: 96/69 eggs in Londrina, and 1091/510 eggs in Manaus, respectively. Also presented lower OPI values (averages: 28%/4% in Londrina, and 88%/60% in Manaus, respectively); and lower EDI values (averages: 10.5/9 in Londrina, and 47/30 in Manaus, respectively). The capture ratios of Aedes adults in the UELtrap-EA and CRtrap-EA traps in Londrina and Manaus were 53.3%/29.5% and 0%/9.8%, respectively. UELtrap-E and UELtrap-EA can be adopted as efficient tools for Aedes monitoring due to their high sensitivity, low cost and ease of use.Author summaryAedes aegypti and Aedes albopictus are species of mosquitoes responsible for the transmission of several arboviruses that cause infections worldwide. However, there are still no effective and safe vaccines or medications to prevent or treat arboviruses transmitted by these vectors, except for yellow fever. Moreover, current methodologies for monitoring and controlling A. aegypti and A. albopictus are not fully effective, as evidenced by the increasing cases of the arbovirus transmitted by these mosquitoes or have incompatible costs with the socioeconomic conditions of a large number of people. Thus, the traps tested in this study can be used as more effective and economical tools for monitoring and controlling A. aegypti and A. albopictus, since they are made with low cost material and they showed high efficiency in the capture of eggs, evidenced by the high values of ovitraps positive index and eggs density index, besides that one of the models captured Aedes spp. adults in both regions where they were tested. Therefore, the traps have potential for reducing Aedes spp. eggs and adults in the environment and sensibility for determining the local infestation index, which can be reconciled with official government strategies for more accurate vector monitoring and control actions.


2021 ◽  
Vol 236 ◽  
pp. 04033
Author(s):  
Shi Shanhai ◽  
Lv Jianqun ◽  
Xu Yongqian ◽  
Xie Xiangyong ◽  
Zhong Haoxian

A device is proposed, which can be used to upgrade the informatization process of old equipment and information isolated island equipment of ceramic enterprises. It has the characteristics of standard, high efficiency, low cost and low risk. The universal fast interface does not interfere with the control system of the device itself when connected to the device. It can obtain data that the target device system has but is not open or the system does not have. Then, the device use the standard industrial communication protocol to transmit the data to the manufacturing execution system in accordance with the agreed data format. This method lay a good foundation for the informatization upgrade and optimization of the data. Furthermore it can be used to optimize and control production. Finally, in enterprise applications, it shows that the device has certain economic and social benefits.


Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.


2019 ◽  
Author(s):  
Charlys Bezerra ◽  
Géssica Santos ◽  
Marilia Pupo ◽  
Maria Gomes ◽  
Ronaldo Silva ◽  
...  

<p>Electrochemical oxidation processes are promising solutions for wastewater treatment due to their high efficiency, easy control and versatility. Mixed metal oxides (MMO) anodes are particularly attractive due to their low cost and specific catalytic properties. Here, we propose an innovative thermal decomposition methodology using <a>polyvinyl alcohol (PVA)</a> as a solvent to prepare Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes. Comparative anodes were prepared by conventional method employing a polymeric precursor solvent (Pechini method). The calcination temperatures studied were 300, 400 and 500 °C. The physical characterisation of all materials was performed by X-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy, while electrochemical characterisation was done by cyclic voltammetry, accelerated service lifetime and electrochemical impedance spectroscopy. Both RuO<sub>2</sub> and IrO<sub>2</sub> have rutile-type structures for all anodes. Rougher and more compact surfaces are formed for the anodes prepared using PVA. Amongst temperatures studied, 300 °C using PVA as solvent is the most suitable one to produce anodes with expressive increase in voltammetric charge (250%) and accelerated service lifetime (4.3 times longer) besides reducing charge-transfer resistance (8 times lower). Moreover, the electrocatalytic activity of the anodes synthesised with PVA toward the Reactive Blue 21 dye removal in chloride medium (100 % in 30 min) is higher than that prepared by Pechini method (60 min). Additionally, the removal total organic carbon point out improved mineralisation potential of PVA anodes. Finally, this study reports a novel methodology using PVA as solvent to synthesise Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes with improved properties that can be further extended to synthesise other MMO compositions.</p>


Author(s):  
José Luis Viramontes-Reyna ◽  
Josafat Moreno-Silva ◽  
José Guadalupe Montelongo-Sierra ◽  
Erasmo Velazquez-Leyva

This document presents the results obtained from the application of the law of Lens to correctly identify the polarity of the windings in a three-phase motor with 6 exposed terminals, when the corresponding labeling is not in any situation; Prior to identifying the polarity, it should be considered to have the pairs of the three windings located. For the polarity, it is proposed to feed with a voltage of 12 Vrms to one of the windings, which are identified randomly as W1 and W2, where W1 is connected to the voltage phase of 12 Vrms of the signal and W2 to the voltage reference to 0V; by means of voltage induction and considering the law of Lens, the remaining 4 terminals can be identified and labeled as V1, V2, U1 and U2. For this process a microcontroller and control elements with low cost are used.


2020 ◽  
Vol 3 (2) ◽  
pp. 68-81
Author(s):  
Abu Sadath ◽  
Farhana Afroz ◽  
Hosne Ara ◽  
Abdulla-Al Kafy

Rivers are the lifeline of Bangladesh economy and serve as the source of water supply, fisheries, irrigation for agriculture, low-cost transport, generate electricity and conserve biodiversity. The Ichamati River situated in Pabna, Bangladesh is also a blessing for the city. However, recently, due to the irregular and unplanned activities adjacent to the riverside, the life, flow and water quality of the river is in a vulnerable condition. This study aims to identify the present status of the Ichamati River and provide an effective design approach and policy measures in restoring the river flow and control water pollution. The data was collected from the questioner surveys, key informant interviews and focus group discussions. Results suggest that several factors such as the construction of an illegal settlement, unplanned waste dumping, disposal of fiscal sludge through sewerage connection, lack of awareness among people regarding the importance of river biodiversity and absence of riverfront development and conservation plan are responsible for water pollution, inconsistent water flow and damaging the life cycle of Ichamati river. The design approach and policy measures were developed based on the perceptions of local community people, experts and government officials. The suggested policy measures will help to restore the flow of the river and reduce the water pollution, and the design approach will ensure the economic benefit of the riverfront development in future.


Author(s):  
Zhengwang Xu ◽  
Wei Mei ◽  
Jiaqi Yu ◽  
Jiarui Zhang ◽  
Yuchun Yi ◽  
...  

As being restricted by factors such as cost, efficiency and size, the development of high-power solar LED street light controller is faced with plenty of difficulties. In case that a structure of two independent DC/DC is applied as the main circuit, it has to face problems such as large size and high cost; in case of applying the bidirectional BUCK/BOOST circuit, it requires change-over switches to control the solar panel and LED light. As being restricted by withstanding voltage, on-resistance and cost, a PMOS device cannot be used as the change-over switch of solar panel and LED light. However, when being used as a change-over switch, an NMOS device must apply the low-side mode under which the negative ends of the mentioned three parts are cut off. In the condition of applying the low-side mode, a differential circuit must be used to detect the voltage of the solar panel. Furthermore, in order to make sure batteries can still be regularly charged after wearing out in daylight, the controller must be supplied with power through a dual power supply circuit that can obtain power from both the solar panel and the battery. The demander has a requirement on extremely low standby power consumption of the product, and thus it is necessary to minimize the circuit that is live while working in standby mode. Methods: The bidirectional BUCK/BOOST circuit structure is applied to the main circuit to realize a higher change-over efficiency while giving considerations to both cost and size. The NMOS device, model IRFB4410ZPBF, with a price of about three yuan, is used as the switching device, and the low-side mode is applied, that is the switches inserted in between negative end of the solar panel or LED light and that of the DC/DC circuit. The low-cost rail-to-rail operational amplifier LM358 is used to form a differential amplification circuit for detecting the voltage of the solar panel. A XL1509-12E1 chip that only costs 0.88 yuan/pc is selected as the main change-over chip for the power supply, which has realized the highly-efficient and low-cost change-over of the power supply. A dual power supply circuit and a step-down protective circuit are designed for the XL1509-12E1 change-over chip. By comparing solar panel voltage with battery voltage, the solar panel booting circuit is realized. Only when solar panel voltage is higher than battery voltage, does the system program start to power it up for running, so that the outage of most of the circuits of the system under standby mode does not consume energy. Furthermore, the solar panel voltage detecting circuit, the solar panel booting circuit and several return difference functions are corrected during system debugging. Results: The circuit board of the entire controller features small size, low cost and high efficiency. It measures about 100*62*18mm in size, costs about 60 yuan, and the charge/discharge change-over efficiency reaches up to over 95%. The controller has many functions: it is capable of operating within a large scope, in which, solar panel voltage is subject to 15~50V, LED light voltage is subject to 15~60V, battery voltage is subject to 10~35V and battery-end charge/discharge current is 10A; it is capable of adapting to monocrystalline silicon/multicrystalline silicon/thin-film and many other kinds of solar panels, as well as lithium/lead-acid and many other kinds of batteries; it is capable of detecting the conversion of day and night, automatically controlling charging and discharging and automatically making adaptive adjustment according to seasonal variations; the current to be consumed during standby will be maintained below 3mA, and thus the power consumption is extremely low. Conclusion: By selecting the bidirectional BUCK/BOOST circuit structure, applying low-side mode for switching of solar panel and LED light, using a differential circuit to detect solar panel voltage, using a low-cost DC/DC chip to realize power supply change-over, designing a dual power supply circuit, introducing solar panel booting circuit and other hardware design, as well as MPPT algorithm, state recognition and control, return difference control and other software design, a solar LED street light control product featuring small size, low cost, high efficiency and multiple functions is successfully developed.


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