Development Of Power Transmission System Research Articles

One High Voltage Regulation Method and Related Control Strategy in the DC Transmission System

Background: With the development of power transmission system, the problem of small transmission capacity and low power quality of traditional AC power distribution methods is becoming increasingly prominent. The DC power distribution method promotes its own rapid development because of its suitability of connection between distributed generation and grid, high power quality, large power supply capacity, low line cost and high reliability. Objective: In order to improve the transient performance when the system power fluctuates, a control method that can perform voltage regulation to the DC system is designed in the process of calculating the power command value of each converter station at the system level control. Simulation results show that the designed control method can effectively improve the inertial characteristics and transient response of DC transmission system. Methods: Aiming at the shortcomings of slow response speed and poor stability when the traditional dual closed-loop PI controller is used as a converter level controller, a sliding mode controller is designed. Simulation results show that the designed sliding mode controller can improve transient characteristics of voltage regulation. Results: Voltage control strategy of the DC transmission network based on the converter station is verified. Conclusion: A voltage control strategy based on distributed generation and secondary load switching is designed. The simulation verifies the effectiveness of the designed control strategy.

Design and Development of Power Transmission System for Tractor Operated Hybrid Bio-Composite Mulch Sheet Laying Machine

Tractor 3 point hitch drawn hybrid bio-composite bio degradable mulch laying machine was designed and developed based on the formulation of the hybrid bio-composite mulch sheets with a intension of the integrate the field operations at easy pace and conserve the time and labour. The prototype was fabricated and tested in the fields in order to perform the operations such as hybrid bio-composite mulch sheet laying, Mulch sheet pressing and guiding and soil covering on the edges of the mulch sheets in one forward movement of the machine. The machine was fabricated with design of many components but the power transmission system was plays a major role in this machine as the entire forward movement of machine and performance of the mulch sheet laying unit was depends on the power transmission system only. Various components of power transmission system was designed such as shafts, chain, bearings and sprockets etc. The shaft design was done considering the two conditions of fields while in operation like considering twisting and bending moments of the shaft as well as sudden applied shocks and fluctuated loads. Considering the two conditions, the main shaft, counter shaft and rear wheel shafts diameters were designed based on this two conditions and obtained results were 30 mm, 40 mm and 25 mm respectively The chain and sprocket will be used for the transmitting the power from one shaft to other one. The length of the chain was calculated 162.56 cm and the HP transmitted by the selected chain and HP of chain drive system were calculated as 2.05 hp and 0.339 hp respectively. Based on the results, the calculated horse power was less than the horse power of selected chain that means required horse power was 0.339 hp but we have got 2.05 hp, hence the design was safe and machine will be operate without any hassles.

Study on sustainable development of power transmission system under ice disaster based on a new security early warning model

As the ecological climate deteriorates, common disasters including typhoons, earthquakes and ice disasters occur frequently in southern China. In particular, ice disasters can make severe ice coating on power line, resulting in power outage accidents. Not only do power supply disruptions cause major economic losses, but also they threaten people's lives in extremely cold conditions. Therefore, studying on the security early warning of ice coating damage to power line is significant and urgent. This paper adopts grey correlation analysis (GRA) to obtain 16 influence factors, of which the correlation degrees are over 0.74. In order to reduce the internal relevance among the impact factors, 5 common factors are extracted as the predictive model input values through factor analysis. With the input weight and hidden layer threshold optimized, a new extreme learning machine based on the adaptive whale optimization algorithm improved by chaotic sine cosine operator (CSCWOA-ELM) is established to forecast the ice coating damage to power line in southern China. To verify the accuracy and advancement of the proposed model, real data from the power repair projects under ice disaster are selected for experiments. The simulation results prove that the extraction of common factors can highly improve the prediction accuracy by approximately 27.80%. Compared with the 3 benchmark models, the CSCWOA-ELM model, of which the root mean square error (RMSE) is 0.02341 and the mean absolute percentage error (MAPE) is 1.82175%, shows a better performance in predicting the ice coating damage to power line.

Design and Development of Power Transmission System for Green and Light Weight Vehicles: A Review

A study on green vehicle was introduced and promoted to minimize the problem of air pollution caused by emissions of conventional vehicle. Green mobility are vehicles with low fuel/energy consumption and low/zero exhaust gas emission, these vehicles are like hybrid, battery powered, and fuel cell electric vehicle that can be enhanced to be more efficient than the conventional vehicles through a new design and development of power transmission system. Power transmission system for green and lightweight vehicles consists of different components like gear box, propeller shaft, differential and final drive. In this review more emphasis is given to gear box due to some reasons: firstly, it is one of the heaviest component of the power train system and as a result weight reduction is critically needed to increase the efficiency of the vehicle. Secondly, gearshift takes place therefore, torque interruption needs to minimize. The use of simulation software's i. e. Mat lab, AMEsim, cruise software and other similar programs can simulate high-efficiency power transmission system. The results from the simulation software will be validated by experimental tests on test rigs. One way of minimizing fuel consumption is to reduce the weight of the gearbox by 10% reduction in vehicle weight can improved fuel economy by about 5-7%. As different researchers confirm that to have high vehicle efficiency the type of the transmission they used matters. A vehicle using automated manual transmission (AMT) and dual clutch transmission is more efficient in terms of less energy loss and gearshift comfort.

ENERGY SCAVENGING IN A VEHICLE’S EXHAUST SYSTEM

Present- day development of power transmission systems, especially the ones based on combustion engines, is trying to cope with the issue of improving the energy efficiency of energy processing systems. One of the directions is to use the techniques of thermal energy recovery from an engine’s exhaust system. Vast part of the energy produced while burning the air- fuel mixture is lost in the cooling and exhaust systems. Research in this area was conducted by numerous teams, both abroad and in Poland, while focusing on use of Peltirea cells. The results of their research demonstrated small efficiency of these cells. In this paper, the authors have focused on modifications of the exhaust system in order to improve heat exchange between the exhaust system’s elements and TEG. The research was conducted while using the ECOTEC 1.8 litre engine from Opel, the X18XE model. The engine was installed in a testbed, in the mechatronic lab at the Faculty of Automotive and Construction Machinery Engineering (SIMR) of Warsaw University of Technology. Spartan HE923 radiators were installed on the cold end of the module. The paper presents the results of the research related to interworking of TEG’s with the exhaust system’s heat-generating elements of various shapes. The paper reviews the energy efficiency of TEG depending on diverse parameters of gas flow. A parallel system has been assumed (controlled stream and pressure of the flowing exhaust gases without any interference as regards the speed of the of combustion engine). The factor-related experiment accounts for the influence that the pressure and temperature difference, depending on the volume and discharge of exhaust fumes, have on the efficiency of TEG for the same temperature. The results of the experiment are presented in the last section of the article.

Contact finite element method for dynamic meshing characteristics analysis of continuous engaged gear drives

The dynamic meshing characteristics of gear drives have been a major concern in the design of power transmission systems as they affect vibration, acoustic noise, durability and efficiency. Gaining a more comprehensive understanding of the dynamic meshing characteristics of continuous engaged gear drives is a key to the development of power transmission systems. In this paper, a dynamic contact finite element analysis method, considering the variation of the engaged teeth pairs, the loaded elastic and contact deformations, and the sliding friction, is presented for the dynamic meshing characteristics analysis of continuous and elastic engaged gear drives. Various kinds of continuous engaged gear models under low and high speed condition are simulated and compared using the presented method. The tooth profile modification was designed based on the simulation results. Moreover, the effects of the tooth profile modification, the sliding friction and the time-varying meshing stiffness upon the dynamic meshing characteristics of continuous engaged gear drives are discussed in detail. The results show that the method is not only effective in designing and evaluating the tooth profile modification, but also in studying the dynamic meshing characteristics of continuous engaged gear drives with realistic time-varying meshing stiffness and tooth sliding friction. The present method could provide an effective tool for vibration mechanism study and dynamic design of the continuous engaged gear drives considering more influence factors.

Manufacturing and commissioning of 24 kV superconducting cable in Detroit

The development of power transmission system based on high temperature superconducting material is reaching an important goal with the ongoing Detroit Edison HTS Cable Project in Detroit, Michigan. AMSC, DOE, EPRI, LANL, Lotepro are the project partners. The system consist into designed 24 kV, 100 MVA three phase superconducting warm dielectric cables, compact terminations, one joint, refrigeration and control/monitoring system. Nine conventional cables in duct have been substituted with only three HTS cables operating at the same voltage and overall current. In this paper we present the status of the project.

Proposed East-West European Power Link-possible impact on the Polish Grid network

The paper makes an introductory analysis on the feasibility of a 4 GW, 1700 km East-West Power Link between Russia and Germany and its possible impact on the Polish Grid network. The paper defines the present scale and proposed development of power transmission systems in Poland and the other potential contributors to the project. After reviewing 3 possible transfer alternatives: via an extended 400 kV Polish Grid System, via a superimposed 750 kV AC line, and via an HVDC line, a multiterminal DC supergrid (MTDC) is presented as the preferable solution. This is on account of MTDC having unique features of power flow control under independent bilateral contracts between Russian, Belarussian, Polish, German and other companies. >

China Light & Power's transmission system development practices

China Light & Power (CLP) is a Public Limited Company with responsibilities to its shareholders, the Hong Kong Government and the public at large in providing a secure, efficient and economical supply of electrical power to its supply area within the territory of Hong Kong. This article traces the history of CLP's transmission system developments over the past 40 years, which has been a period of vigorous and continuous growth and has produced some original engineering solutions to a range of unique problems encountered. Particular aspects of compact substation developments, within the densely populated Kowloon area, will be highlighted. A self-sufficient capability with a strong awareness of cost effectiveness have been central influencing factors in the development of the CLP system