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New Delhi, India

An G.-D.,Indian Ministry of Railways
Tiedao Xuebao/Journal of the China Railway Society | Year: 2010

The technique of precise engineering surveying for high-speed railways is one of the key techniques to construct high-speed railways successfully. According to the requirements for track smoothness of high-speed railways, this paper expounds the surveying principle for integration of the surveying control network in the three phases of design, construction and operation through studies on theories and tests, explores systematically the technical standards for the coordinate system of high-speed railway plane and elevation control surveying, the height datum, the principle for network distribution, surveying methods and precision as well as the confirmation regulations. The recent practical construction and operation of high-speed railways verify the scientific and advanced nature, adaptability and reliability of the technical standards for precise engineering surveying of high-speed railways in our country. Source

Singh D.,Indian Institute of Technology BHU Varanasi | Misra R.K.,Indian Institute of Technology BHU Varanasi | Mishra S.,Indian Ministry of Railways
International Journal of Electrical Power and Energy Systems | Year: 2016

Phase-balancing creates voltage changes in the network which calls for incorporating voltage-dependency of loads in the process of phase-balancing. Hence, inclusion of voltage-dependency in current-injection based three-phase load flow is investigated and the results are compared with constant-power load model in terms of phase-balancing. The problem being combinatorial, application of particle swarm optimization is investigated for phase-balancing problem of radial distribution network. The effects of phase unbalance and load representation are studied in terms of various parameters. It is observed that there are situations that lead to increase in losses despite improvement in phase-balancing. © 2015 Elsevier Ltd. Source

Singh B.,Indian Institute of Technology Delhi | Niwas R.,Indian Ministry of Railways
IEEE Transactions on Industry Applications | Year: 2016

This paper presents power quality improvement of a permanent-magnet-synchronous-generator-based diesel generator (DG) set feeding three-phase loads using a static compensator (STATCOM). A three-leg voltage-source converter (VSC) with a capacitor on the dc link is used as a STATCOM. The reference source currents for the system are estimated using an Adaline-based control algorithm. A pulsewidth modulation current controller is used for generation of gating pulses of insulated-gate bipolar transistors of the three-leg VSC of the STATCOM. The STATCOM is able to provide voltage control, harmonics elimination, power factor improvement, load balancing, and load compensation. The performance of the system is experimentally tested on various types of loads under steady-state and dynamic conditions. A three-phase induction motor with variable-frequency drive is used as a prototype of diesel engine with the speed regulation. Therefore, the DG set is run at constant speed so that the frequency of supply remains constant irrespective of loading condition. © 1972-2012 IEEE. Source

Gautam A.,Indian Institute of Technology Kanpur | Gautam A.,Indian Ministry of Railways | Agarwal A.K.,Indian Institute of Technology Kanpur
International Journal of Engine Research | Year: 2013

A large-bore, four-stroke, medium-speed, compression-ignition railway traction locomotive engine was fueled with cottonseed methyl ester (Biodiesel). The cottonseed methyl ester was stored for 6 months under ordinary storage conditions, and various fuel properties of this seasoned cottonseed methyl ester were evaluated. Various blends of cottonseed methyl ester (B10, B20, B50 and cottonseed methyl ester) were evaluated for engine performance, emissions and combustion characteristics of the locomotive engine compared to baseline diesel. Correlation of the fuel-injection performance parameters with the physical properties of biodiesel has been carried out. The engine was able to operate on cottonseed methyl ester without noticeable power loss. With cottonseed methyl ester, the thermal efficiency decreased marginally by 0.7% and the brake-specific energy consumption increased by 0.1 MJ/kWh at the rated power. Due to the lower calorific value of biodiesel, brake specific fuel consumption (BSFC) increased by 13.4% at eighth engine notch, nitrogen oxide emissions increased by 8% and particulate matter emissions decreased by 32% vis-a-vis mineral diesel. Nitrogen oxide emissions were found to be a function of injection timings, global oxygen/carbon ratios, time of the maximum mean in-cylinder temperatures and apparent heat release. Particulate matter emissions were found to depend on the air-fuel mixture's oxygen/carbon ratio, fuel bound oxygen and fuel-injection pressure. The experiments were carried out to evaluate the in-cylinder pressure, heatrelease rate, cumulative heat release, fuel-injection pressure, needle lift and fuel-injection velocities. Increased fuel-injection pressures (1000 bar compared to 900 bar for mineral diesel), advanced fuel-injection timings, shorter combustion duration, advanced in-cylinder pressures and higher heat-release rates were observed for biodiesel and blends. The findings of the present study have provided further insights into the combustion of biodiesel in locomotive engines. © 2012 IMechE. Source

Mishra S.,Indian Ministry of Railways
Water and Energy International | Year: 2013

Conventional ac traction power is a Single Wire Earth Return (SWER) System, This places challenge on, containment of the touch potential of the rail. As traction powers increase, return current management which is closely related to the earthing and bonding practice, becomes an important factor to be considered in the economics & safety of traction power supply-under which billions of kilo metres of freight and passenger movement is logged. Further, need of structure and platform earthing is emerging as a major challenge to guarantee safety to the users, with steadily increasing transformation capacity in traction sub-stations. Similarly, dc traction systems pose an entirely different set of challenges to the adjoining non-railway installations. The presentation aims to flag the issues and provide Indian Railways' experience and global practices. Source

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