1207 A Study of Power Transmission Efficiency in Belt Drives : Effect of Belt Configuration in Storage on Driving Torque Fluctuation

2006 ◽  
Vol 2006.6 (0) ◽  
pp. 35-36
Author(s):  
Tomio KOYAMA ◽  
Taro ISHIHARA ◽  
Weiming ZHANG ◽  
Masanori KAGOTANI
Keyword(s):  
Power Transmission ◽  
Transmission Efficiency ◽  
Belt Drives ◽  
Driving Torque

Improving the efficiency of oilfield electric power distribution

2019 ◽  
pp. 79-87
Author(s):  
Yu. F. Yu. F. Romaniuk ◽  
О. V. Solomchak ◽  
М. V. Hlozhyk
Keyword(s):  
Power Distribution ◽  
Reactive Power ◽  
Power Transmission ◽  
Transmission Efficiency ◽  
Active Power ◽  
Oil Field ◽  
Total Power ◽  
Simultaneous Increase ◽  
Active Load ◽  
Step Down

The issues of increasing the efficiency of electricity transmission to consumers with different nature of their load are considered. The dependence of the efficiency of the electric network of the oil field, consisting of a power line and a step-down transformer, on the total load power at various ratios between the active and reactive components of the power is analyzed, and the conditions under which the maximum transmission efficiency can be ensured are determined. It is shown by examples that the power transmission efficiency depends not only on the active load, but also largely on its reactive load. In the presence of a constant reactive load and an increase in active load, the total power increases and the power transmission efficiency decreases. In the low-load mode, the schedule for changing the power transmission efficiency approaches a parabolic form, since the influence of the active load on the amount of active power loss decreases, and their value will mainly depend on reactive load, which remains unchanged. The efficiency reaches its maximum value provided that the active and reactive components of the power are equal. In the case of a different ratio between them, the efficiency decreases. With a simultaneous increase in active and reactive loads and a constant value of the power factor, the power transmission efficiency is significantly reduced due to an increase in losses. With a constant active load and an increase in reactive load, efficiency of power transmission decreases, since with an increase in reactive load, losses of active power increase, while the active power remains unchanged. The second condition, under which the line efficiency will be maximum, is full compensation of reactive power.  Therefore, in order to increase the efficiency of power transmission, it is necessary to compensate for the reactive load, which can reduce the loss of electricity and the cost of its payment and improve the quality of electricity. Other methods are also proposed to increase the efficiency of power transmission by regulating the voltage level in the power center, reducing the equivalent resistance of the line wires, optimizing the loading of the transformers of the step-down substations and ensuring the economic modes of their operation.

Compensating Resonant Frequency via Adjusting Adjustable Coil Automatically

2019 ◽  
Vol 12 (5) ◽  
pp. 432-438
Author(s):  
Jin Xu ◽  
Yuting Zhao
Keyword(s):  
Resonant Frequency ◽  
Power Transmission ◽  
Reference Value ◽  
Transmission Efficiency ◽  
Theoretical Research ◽  
Future Research ◽  
Wireless Power ◽  
Wireless Power Transmission ◽  
Resonant Coupling ◽  
Transmission Distance

Background: Detuning is the main problem that affects the efficiency and transmission distance of the resonant coupling Wireless Power Transmission (WPT). The distance of load and the offset of the load position could cause serious detuning. Methods: This paper presents an adjustable coil in which inductance can be adjusted. Then a model of WPT was established that could compensate resonant frequency automatically using the adjustable coil. Next, the relationship between the primary resonant frequency and the transmission efficiency is analyzed from the circuit. The analysis proved that the design of the adjustable coil could improve the transmission efficiency of the WPT system. Finally, a prototype of WPT system was built. Results: The experimental results showed that WPT system with adjustable coil can improve the transmission efficiency which proves the theoretical research. At the same time, it has essential reference value for the future research of WPT. Conclusion: In this paper, aiming at the system detuning caused by some other factors, such as the position shift of the load during the wireless power transmission, an adjustable coil is proposed.

scholarly journals Design of a Loop Resonator with Improved Power Transmission Efficiency Using a Ferrite Plate

2013 ◽  
Vol 05 (05) ◽  
pp. 196-200 ◽  
Author(s):  
Gangil Byun ◽  
Sunghwan Ji ◽  
Byungjun Jang ◽  
Chulhun Seo ◽  
Hosung Choo
Keyword(s):  
Power Transmission ◽  
Transmission Efficiency ◽  
Ferrite Plate

scholarly journals The power transmission stability and efficiency of V-belts

2016 ◽  
Vol 12 (1) ◽  
pp. 25-49
Author(s):  
László Kátai ◽  
Péter Szendrő ◽  
Péter Gárdonyi
Keyword(s):  
Internal Friction ◽  
Food Industry ◽  
Power Transmission ◽  
Angular Displacement ◽  
Hysteresis Loss ◽  
Damping Factor ◽  
Belt Drive ◽  
Agricultural Machinery ◽  
Plate Structure ◽  
Belt Drives

The V-belt drive is a rather popular, widely used form of power transmission in agricultural and food industry engineering. At the same time, its stability, the lifetime of V-belt is influenced by several environmental factors, namely in the food industry by the contamination affecting the belt sides, the ambient temperature, humidity and the occasionally aggressive (acidic, alkaline air, air saturated with gases, etc.) medium. In the case of agricultural machinery, the vibration caused by uncertainly oriented pulleys with bearing in different plate structures (often being shaken in the fields) as well as alignment adjustment inaccuracies jeopardize the reliability of the parameters of the drive. Furthermore, the efficiency is determined by several factors together: the slippage occurring during drive transmission, the hysteresis loss resulting from the external and internal friction occurring with the belt entering and exiting the pulley. Experimental equipment and calculation methods were developed to determine the dynamics of temperature increase generated by the belt and pulley relationship. The temperature generated in the V-belt was measured as a function of pretension, pulley diameter and bending frequency. The so-called damping factor characterizing the contact with the pulley (the external friction when entering and exiting the groove) and the hysteresis loss (inner friction) are also determined. On the basis of the damping factor (ζ ≈ 400 Ns/m2) of the V-belt involved in the experiments the other losses (Poth) occurring from the pulley—V-belt contact and internal friction may be estimated. The drive parameters may be optimized with the mathematical model describing the effect of the pulley diameter and belt frequency on the increase in temperature. A standardized calculation method as well as design factors valid for the properly adjusted drive and normal operating conditions determined through empirical and laboratory experiments are used for the sizing of V-belt drives. The lifetime of V-belt drives designed in this way, used in extreme conditions typical of agricultural machinery will not be appropriate and will not provide clear, predictable information for maintenance planning. In such cases the results of our own many lifetime tests conducted in the given circumstances can be safely relied on. The agricultural harvesting machines are large plate-body self-propelled structures on which most of the power supply of the (threshing, cleaning, moving, etc.) machine units handling the crop is realized via belt drives. The distance and angular displacement of the axes involved in the drive can vary within wide limits. The misalignment and angular displacement of the pulleys can be the result of installation instability — due to the plate structure — and the deformation of the plate structure occurring during the operation as well. V-belt drives operate satisfactorily under such conditions as well, however these faults are unfavourable in terms of belt lifetime and result in the reduction of drive efficiency. A further aim of our research is to examine through experiments the lifetime and efficiency of V-belts used in agricultural machines as a function of drive adjustment errors. According to the results of the measurements of the geometrical adjustment errors of V-belt drives performed in the field, the pulleys of agricultural equipment are not always positioned in the medium plane of the drive. In our experiments these data served as independent variables. Figure 1 shows the arrangement of a V-belt drive in a grain harvester with the laser pulley alignment measuring instrument installed as an accessory. In the case of many machine types in 80% of the tested drives three times the permissible error was measured, and because of off-road use, due to dynamic load these errors further increased as a result of the frame deformation. The results of both the belt bending testing and the geometrical adjustment testing of the drive offer great help in the design of belt drives. At the same time they can be the source of lifetime and efficiency forecasts.

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