Controlled Series Compensation of High Voltage Lines to Increase Transmission Capacity

Author(s):  
Valery Golov ◽  
Andrew Kalutskov ◽  
Dmitry Kormilitsyn
Author(s):  
Baina He ◽  
Yadi Xie ◽  
Jingru Zhang ◽  
Nirmal-Kumar C. Nair ◽  
Xingmin He ◽  
...  

Abstract In the transmission line, the series compensation device is often used to improve the transmission capacity. However, when the fixed series capacitor (FSC) is used in high compensation series compensation device, the stability margin cannot meet the requirements. Therefore, thyristor controlled series compensator (TCSC) is often installed in transmission lines to improve the transmission capacity of the line and the stability of the system. For cost considerations, the hybrid compensation mode of FSC and TCSC is often adopted. However, when a single-phase grounding fault occurs in a transmission line with increased series compensation degree, the unreasonable distribution of FSC and TCSC will lead to the excessive amplitude of secondary arc current, which is not conducive to rapid arc extinguishing. To solve this problem, this paper is based on 1000 kV Changzhi-Nanyang-Jingmen UHV series compensation transmission system, using PSCAD simulation program to established UHV series compensation simulation model, The variation law of secondary arc current and recovery voltage during operation in fine tuning mode after adding TCSC to UHV transmission line is analyzed, and the effect of increasing series compensation degree on secondary arc current and recovery voltage characteristics is studied. And analyze the secondary arc current and recovery voltage when using different FSC and TCSC series compensation degree schemes, and get the most reasonable series compensation configuration scheme. The results show that TCSC compensation is more beneficial to arc extinguishing under the same series compensation. Compared with several series compensation schemes, it is found that with the increase of the proportion of TCSC, the amplitude of secondary arc current and recovery voltage vary greatly. Considering various factors, the scheme that is more conducive to accelerating arc extinguishing is chosen.


Vestnik IGEU ◽  
2020 ◽  
pp. 14-24
Author(s):  
V.P. Golov ◽  
A.V. Kalutskov ◽  
D.N. Kormilitsyn ◽  
O.S. Sukhanova

Currently there is a need to synchronize operation of the electric power system in the remote areas and increase of existing lines transmission capacity. The construction of new power transmission lines involves high economic expenditures. Well-known papers consider the issues of application of controlled series compensation devices only for long-distance power transmission lines with voltage of 500 kV and higher to increase the transmission capacity and the level of stability. The aim of the study is to increase the stability and the limit of the transmitted power when controlled series compensation devices are installed on 220 kV lines. It is necessary to develop a criterion of aperiodic steady-state stability of an electric power system with a 220 kV-controlled power transmission line. Methods of mathematical modeling of electric power system, the theory of long-distance power transmission lines and electromechanical transients, and methods of analyzing electric power system stability were used. A.M. Lyapunov’s first approximation method was used to develop a simplified mathematical model. We applied the developed software as a simulation tool. An analysis was carried out to study the influence of series compensation devices regulation coefficients on the aperiodic steady-state stability of the electric power system and the transmission capacity of 220 kV power transmission lines. A change in the modulus of voltage drop at the power transmission and the angle characteristics under the influence of the regulation coefficients of the series compensation device was revealed. A criterion of aperiodic steady-state stability has been developed for systems of this kind with controlled series compensation. It differs from traditional ones by considering the changes in the voltage drop in the power transmission and it allows more accurate estimation of the proximity to the stability threshold. An assessment of aperiodic steady-state stability according to the formulated criterion for an electric power system with a controlled series compensation device on a 220 kV line was obtained. The values of the control coefficients of the series compensation device have been determined. No violation of the steady-state stability occurs under the given values. The results can be used to solve the issues of increasing the transmission capacity of transmission lines to improve the stability of the system.


2019 ◽  
Vol 17 (3) ◽  
pp. 22-31 ◽  
Author(s):  
Tayeb Meridji ◽  
Frida Ceja-Gomez ◽  
Jose Restrepo ◽  
Ramy Azar

2014 ◽  
Vol 664 ◽  
pp. 318-325
Author(s):  
Jian He ◽  
Xian Xin Li

This paper discusses the feasibility and effectiveness of the application of expanded conduct in 1000kVultra high voltage AC (UHVAC) transmission line. Through the comparison and analysis between expanded conduct and conventional conduct in transmission capacity, mechanical properties, project investment, annual cost and other aspects, it shows that the initial investment of expanded conduct is 4% lower than that of conventional conduct; and the annual cost of expended conductor is superior to that of conventional conduct when transmission capacity, power price and use hours are low.


Author(s):  
L. D. Ackerman ◽  
S. H. Y. Wei

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.


Author(s):  
Lee D. Peachey ◽  
Clara Franzini-Armstrong

The effective study of biological tissues in thick slices of embedded material by high voltage electron microscopy (HVEM) requires highly selective staining of those structures to be visualized so that they are not hidden or obscured by other structures in the image. A tilt pair of micrographs with subsequent stereoscopic viewing can be an important aid in three-dimensional visualization of these images, once an appropriate stain has been found. The peroxidase reaction has been used for this purpose in visualizing the T-system (transverse tubular system) of frog skeletal muscle by HVEM (1). We have found infiltration with lanthanum hydroxide to be particularly useful for three-dimensional visualization of certain aspects of the structure of the T- system in skeletal muscles of the frog. Specifically, lanthanum more completely fills the lumen of the tubules and is denser than the peroxidase reaction product.


Author(s):  
L. E. Thomas ◽  
J. S. Lally ◽  
R. M. Fisher

In addition to improved penetration at high voltage, the characteristics of HVEM images of crystalline materials are changed markedly as a result of many-beam excitation effects. This leads to changes in optimum imaging conditions for dislocations, planar faults, precipitates and other features.Resolution - Because of longer focal lengths and correspondingly larger aberrations, the usual instrument resolution parameter, CS174 λ 374 changes by only a factor of 2 from 100 kV to 1 MV. Since 90% of this change occurs below 500 kV any improvement in “classical” resolution in the MVEM is insignificant. However, as is widely recognized, an improvement in resolution for “thick” specimens (i.e. more than 1000 Å) due to reduced chromatic aberration is very large.


Author(s):  
T. Mukai ◽  
T. E. Mitchell

Radiation-induced homogeneous precipitation in Ni-Be alloys was recently observed by high voltage electron microscopy. A coupling of interstitial flux with solute Be atoms is responsible for the precipitation. The present investigation further shows that precipitation is also induced at thin foil surfaces by electron irradiation under a high vacuum.


Sign in / Sign up

Export Citation Format

Share Document