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This paper presents a new study of power system transient fault recognition using Wavelet Multi-Resolution Analysis (MRA) technique integrated with Neural Network. The proposed method requires less number of features as compared to conventional approach for the identification. The feature extracted through the wavelet is trained by a Probabilistic Neural Network for the classification of events. After...
Gas insulated switchgears (GIS) are playing an important role in today's power systems. These are being used in many transmission and distribution substations because of their compactness and durability. The basic insulation coordination levels are well defined in the international standards. The ratio of lightning impulse withstand voltage level to per unit voltage varies for different system voltages...
This paper presents the prestriking and re-striking phenomenon caused by switching disconnect switches in a highvoltage switchyard. A detailed transient model of a representative utility 345 kV substation was developed in the electromagnetic transient program, EMTP-RV and the phenomenon was studied for different cases of multiple prestrike transients. It was determined that the transient voltages...
In this paper, two technologies are used to mitigate transients caused by capacitor switching in distribution feeders. The basic concept of capacitor bank switching transients and its mitigating techniques is presented here. The MATLAB /SIMULINK software is used to simulate the energization of a controlled capacitor bank in a specific substation feeder, with and without employing mitigation devices...
Switching operations of circuit breaker, disconnector and fault conditions in a Gas Insulated Substations (GIS) leads to Very Fast Transient Over voltages (VFTO) and Very Fast Transient Currents (VFTC) are developed. These VFTO's and VFTC's leads to generation of Electromagnetic fields in a gas insulated substations. These Electromagnetic fields due to VFTO's and VFTC's leads to greater damages on...
In this contribution, the investigation on the failures of 115-kV capacitor banks during switching in Chiang Mai 3 substation is presented. The switching transient is caused by energizing an isolated bank and back-to-back switching. Close time of circuit breaker for energizing capacitor bank, system loads, and power factors are varied in the simulations by PSCAD/EMTDC program to determine the causes...
One of the most common problems in sparsely connected power systems is the reduction of power transfer capabilities, due to voltage stability problems. They usually appear in electrically distant and poorly compensated parts of a power system with concentrated consumption. This paper presents one approach to solve the voltage issues, by introducing FACTS devices, like Static Var Compensators (SVC)...
Heat pumps are vitally important for achieving low carbon and renewable energy targets. There is a rapid increase in heat pump installations in the UK and Europe in the last few years for their supporting role towards green energy and demand-side management. The increase in heat pump installation prompts research work on the impact of high penetration of heat pumps on the low voltage network. This...
This work is concentrated on transfer of power quality disturbances in active distribution network containing small hydro power plants (SHP). Investigations are based on the dispersed synchronized measurements using power quality recorder installed in the two substations connected to the same medium voltage line. Dynamic aspect of SHP work represented by switching on capacitor banks are tracked in...
The Smart Grid concept is conceived as a means to optimize and to improve the reliability of the electric delivery system. The numerous and different types of information generated at the remote sites at a distribution network by sensors and smart meters coupled with a communication infrastructure and data base management system provide the means to generate useful control algorithms. However, control...
This paper presents a wireless distributed system to measure transient electromagnetic field in power substations. Taking advantage of flexible short-range wireless technique, the system allows flexible multi-node simultaneous measurement while is of compact size and low cost.
This paper presents the simulation investigation of multi-step back-to-back capacitor bank switching in a 115 kV substation of the Electricity Generating Authority of Thailand in order to observe inrush current, peak oscillating voltage and frequency of transient oscillation. Different cases are simulated such as energization of 24 MVAR back-to-back capacitor banks up to 5-step with and without the...
Coupling capacitor voltage transformers (CCVT) are widely used in power systems and the failure of this equipment may result unexpected outages of transmission lines (TL). This study shows that switching-off shunt reactor compensated TL may lead to sustained voltage amplification in the secondary of the CCVT, the product of a transient interaction between the TL and CCVT, which causes thermal and...
The power quality of electrified railway has become one of the close attentive questions of public electric power systems in China and abroad at present. One of the effective measures to improve the power quality of the electric railway is to install SVC (TCR+FC) equipment in the traction substations. This paper presents the analysis of switching transients of the reactive power compensator, which...
Service conditions, electrical ratings, thermal ratings, and environmental testing requirements are defined for communications networking devices to be installed in electric power substations. This standard establishes a common reproducible basis for designing and evaluating communications networking devices and the communications ports of protective relays for use in this harsh environment.
The development of an electromagnetic transient model to assess potential transient switching issues on a proposed three-ended 400 kV cable circuit is described. The key features of the PSCAD-EMTDC simulation tool and the methodology of model development and testing are discussed. Typical study results and the overall conclusions drawn from these are presented. The paper demonstrates how analysis...
Many new technologies especially micro electronic components have been widely used in the secondary system of the HVDC converter stations. When switch operated there would be kinds of actuating of relay in secondary system. The action of relay tip will generated electromagnetic disturbance (EMD) which will transmit to the protect devices along the secondary cables. The results of an experimental study...
The electro magnetic compatibility (EMC) is serious in the substation, so studying the electromagnetic environment of the key equipment in the substation is very important. We introduce the simulation and calculation of the power-frequency electromagnetic fields of bus and lines between equipments, transient high-frequency electromagnetic fields of the key equipment during switch operation or over-voltage,...
Switching overvoltages due to disconnector switching in air-insulated substations are presented. Shapes and levels of switching overvoltages by means of experimental and computing investigations on 220 kV switchyards of Public Enterprise Elektroprivreda BiH are presented. The influence of resistance of electric arc between the contacts of disconnector is analysed. Computer simulations by means of...
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