Application of a protection scheme to mitigate the impact of load rejection in a 500 kV transmission system

Author(s):  
Waruna Chandrasena ◽  
David A.N. Jacobson
Author(s):  
Henrik Vinge Karlsson ◽  
Britt Gadesboll Larsen ◽  
Per Sorensen

Danish law establishes a common right of passage on foot along the Danish shoreline, even though beaches are often privately owned. The law also states that coastal protection must not hinder this. Therefore, sand nourishment should be part of every coastal protection scheme against erosion. Sand nourishments can be designed in numerous ways depending on their objectives. As part of the European Interreg project, Building With Nature (BWN), guidelines will be developed by the Danish Coastal Authority (DCA) in end-2020. This abstract presents these guidelines with special focus on the coasts of Denmark. Special emphasis will be on insight into the natural variation of the coasts, as this is vital both when designing effective coastal protection schemes and when evaluating the impact of the nourishment. In this project, the pathway along which sediment is being transported spans from offshore at the outer bar to the coastal cliff. The aim is to be able to determine the along- and cross-shore paths, along which the nourishment sand is transported, the diffusion velocity of the nourishment and the impact on the surrounding coasts. Based on the results of the multiple analysis, the primary objective is to produce guidelines on how to use sand nourishment to counteract erosion in a sustainable and socioeconomic way.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/nIrFFmH98V8


This paper focuses on the impact of different parameters on the performance of the Subcarrier Multiplexed Optical Transmission System for the application on radio link via optical fiber. Performance results are evaluated for QPSK data format for ODSB and OSSB modulation of Microwave subcarriers with digital NRZ coded random data patterns. The four subsystems of QPSK modulators are at 400, 500, 600, 700 MHz subcarrier frequencies with frequency spacing of 100 MHz. The power of subcarriers is decreasing with increasing the link distance due to dispersion and attenuation. By using dispersion compensation fiber, the link distance has been enhanced from 100 km to 240 km successfully. The impact of chromatic dispersion has been reduced in OSSB by using dual-electrode MZM. The constellation diagram also confirms that the phase of the signal after traveling through the link is changing due to dispersion. The phase is the same for subcarrier 600 MHz & 700 MHz for ODSB and OSSB in QPSK SCM. The impact of linewidth and responsivity on SNR has also analyzed to evaluate the performance. It is concluded that the maximum SNR is decreasing with increase in the linewidth of laser source and increasing with the increase in responsivity of PIN diode for the same fiber length in SCM transmission.


Author(s):  
Diana G. San Benito Pastor ◽  
Devaiah Nalianda ◽  
Vishal Sethi ◽  
Ron Midgley ◽  
Andrew Rolt ◽  
...  

Abstract This study introduces an innovative approach to sizing a differential planetary gearbox for a counter-rotating open rotor application. An updated methodology is proposed for the design of maximum load capacity gears based on the power transmitted, durability and space-envelope requirements of the application. The reported methodology has been validated by comparing the results to published data, demonstrating a maximum difference of 0.6% in geometry. Parametric analyses have also been performed to assess the impact of the design assumptions on gearbox dimensional trends. The proposed methodology enables the assessment of the impact of the preliminary transmission system design on engine performance and general arrangement. The characteristics of the gearset lead to an unequal torque split between output shafts (i.e. the propeller shafts). Given the design assumptions made, the study indicates that valid torque ratios would lie between 1.1 and 1.33. The impact of the torque ratio on the size of the gearbox has been analysed for equal rotational speeds and for different speeds between the output shafts. The study established that the transmission system design needs to be considered prior to selection of the torque ratio at engine design level.


Author(s):  
Hualei Wang ◽  
Hanjing Zhang ◽  
Chengqing Song ◽  
Chao Xu

2018 ◽  
Vol 19 (6) ◽  
pp. 53-56
Author(s):  
Piotr Bojar ◽  
Mariusz Mikulski

The drivers' workplace has an impact on the safety of transport. Among the factors causing changes in driver behavior are the anthropechnical factors resulting from the actions of people in the vehicle and its surroundings, external ones resulting from the impact of weather conditions as well as the condition of the infrastructure and work resulting from the operation of the means of transport.One of such working factors is the noise which may be the source of: a drive unit, drive transmission system, suspension system, etc. The paper attempts to identify and assess the impact of this factor on the energy consumption of the driver's work.


Author(s):  
Savarapu Chandra Sekhar ◽  
G. Ravi Kumar ◽  
S.V.N.L Lalitha

The power plants behavior is crucial under faulted conditions and responses on protection systems. Major microgrid (MG) protection problem is the problem between the fault current in utilitygrid mode and microgrid mode. As conventional protection system doesn’t offer solution for all MG protection challenge, but it needs advanced protection strategy. Protection system must response to both the utilitygrid and MG faults. Fast response of protection is necessary as early as possible if the fault is occurs on utilitygrid and if the fault is occurs on MG, the protection scheme must seperate the small possible portion of MG to remove the fault. This work presents a typical MG protection scheme using digital relaying and satellite communication with wavelet detailed D<sub>1</sub>-coefficients of mother wavelet Bior 1.5. This research work is done for the detection, discrimination and locality of faults at distributed generators (DG’s) integration in multi-terminal transmission system. The algorithm tested under various faults with fault inception angles (FIA), fault impedances and fault distance of feeder line.


Author(s):  
Kasimala Venkatanagaraju ◽  
Monalisa Biswal

Protection of transmission system is crucial for the secured and stable operation of power system. Under stress conditions, the operating parameters of power system violate their limits. From the past anatomy reports of several blackouts, it is clear that equipment, control, and protective relay failures are the major causes behind large power system failure. From study, it is also revealed that failure of back-up protection is more prone during system stressed conditions. In transmission system, third-zone of distance relay is highly affected by system stressed events such as voltage instability and load encroachment. As third-zone protection is a delayed protection scheme, with the help of wide area measurement system better protection function can be provided to reduce future percentage of blackout. In this chapter, a detailed discussion about the existing solutions is provided to mitigate the issue of system stressed conditions and a synchrophasor technology-based approach is provided. Results for different cases are provided to show the efficacy of the proposed method.


Sign in / Sign up

Export Citation Format

Share Document