# International Conference on AC and DC Power Transmission

## Filter Results

Displaying Results 1 - 25 of 77
• ### Multiterminal HVDC system control using a distributed computing technique

Publication Year: 1991, Page(s):114 - 119
| |PDF (280 KB)

HVDC schemes are poised for a more significant level of acceptance in the large power transmission grid because of the proven experience that has been accumulated over many years with two terminal systems. Recent trends indicate that more multiterminal HVDC systems are emerging as an option for expansion. Derivation of the control strategy for a multiterminal case, however, requires the handling o... View full abstract»

• ### Subsynchronous oscillation controller for Vindhyachal back-to-back HVDC link

Publication Year: 1991, Page(s):290 - 294
| |PDF (212 KB)

The Vindhyachal back-to-back HVDC link interconnects the 400 kV AC networks of the Northern and Western power in India. The phenomena of subsynchronous oscillations due to adverse interaction between turbine generator torsional modes of oscillations and an HVDC system was discovered in 1977. To avoid damage to turbine-generator sets, it is therefore necessary to get a positive damping contribution... View full abstract»

• ### The single European energy market: the electricity supply sector

Publication Year: 1991, Page(s):60 - 62
| |PDF (152 KB)

The completion of the internal market in the Community by the end of 1992 has become a key objective and the focal point of the revival of the European Community. Within this overall objective, the development of the single European energy market, the internal energy Market, is a major element. Here, the author has attempted to give the background to the development of the internal energy market. ... View full abstract»

• ### Stability and safety margins of a weak station within a multiterminal HVDC system

Publication Year: 1991, Page(s):108 - 113
| |PDF (376 KB)

Interaction with inverters at AC power systems with low relative short-circuit capacity have been summarized recently. In a multiterminal HVDC system an inverter station which is weak in rated power, in the short-circuit-ratio, or both, poses some even more difficult problems. The authors examine the stability and safety margins of weak rated-power invertor operation in HVDC systems, using the res... View full abstract»

• ### Network interaction tests of the Fenno-Skan HVDC link

Publication Year: 1991, Page(s):285 - 289
| |PDF (316 KB)

The network interaction tests of the Fenno-Skan HVDC link between Finland and Sweden are described. The authors deal with the objectives, execution and analysis of the tests on the Finnish side. The purpose of the tests was to verify the compatibility of the link with the AC system. Besides this, the tests gave the possibility of verifying the quality of the system modelling. The large scale netwo... View full abstract»

• ### The structure and operation of the privatised UK electricity supply industry

Publication Year: 1991, Page(s):55 - 59
| |PDF (312 KB)

The National Grid Company has just over a years experience in running the England and Wales Grid System as a plc in a market led environment. The industry has been restructured for privatisation with NGC Holdings, owner of NGC plc, being jointly owned by the 12 Regional Electricity Companies. The successful flotation of the 12 Regional Electricity Companies at the end of 1990 included the business... View full abstract»

• ### Simulator study on line fault clearing by DC circuit breakers in a meshed MTDC system

Publication Year: 1991, Page(s):102 - 107
Cited by:  Papers (1)
| |PDF (360 KB)

HVDC multiterminal power systems, here referred to as MTDC systems, request increasing interest after the first schemes of this kind are in operation or under commissioning, respectively. A variety of system configurations can be defined whose properties concerning flexibility, reliability and economics are significantly different. Amongst them the meshed MTDC system offers the important advantage... View full abstract»

• ### Adjustable speed operation of pumped hydroplants

Publication Year: 1991, Page(s):424 - 427
Cited by:  Patents (1)
| |PDF (240 KB)

With a frequency synchronous converter at the main terminals of a generator or at the collector rings of a three phase rotor it would be no longer necessary to tie the electrical machine synchronously to the grid, so the speed of the hydraulic turbine could be adjusted freely to satisfy the load demand at the maximum possible hydraulic efficiency. In this way the adjustable speed operation of a pu... View full abstract»

• ### Active and reactive power controls for the Gezhouba-Shanghai HVDC transmission scheme

Publication Year: 1991, Page(s):279 - 284
Cited by:  Papers (2)
| |PDF (340 KB)

The ±500 kV, 1200 MW HVDC transmission scheme, the first in China, interconnects the Central and Eastern China regional power systems over a distance of 1045 km. The scheme, known as GESHA, was commissioned in two stages in 1989 and 1990 respectively. The authors present a brief description of the HVDC transmission scheme and its principal modes of operation and the operating environment of... View full abstract»

• ### Reactive compensation using static VAR compensators-a planning case study using security constrained techniques

Publication Year: 1991, Page(s):50 - 54
| |PDF (276 KB)

Optimal power flow programs have been widely advocated for voltage performance planning. The National Grid Company (NGC), however, has found that they do not yet address the particular problems encountered on its transmission system. The author illustrates the nature of these problems which require the use of security constrained techniques and describes a method which has enabled a practicable mi... View full abstract»

• ### System variable evaluation with digital signal processors for SVC applications

Publication Year: 1991, Page(s):255 - 260
Cited by:  Papers (1)  |  Patents (2)
| |PDF (320 KB)

The practical implementation of digital signal processors (DSP) is illustrated by describing a voltage regulator which is used to control a static VAr compensator (SVC). Extensive transient network analyser tests showed that signal processors used for system voltage evaluation yield results that are entirely equivalent to those obtainable by analogue methods. Digital methods necessarily and inevit... View full abstract»

• ### Interconnection of a large hydro power plant via HVDC and AC links with two remote grids

Publication Year: 1991, Page(s):96 - 101
Cited by:  Papers (1)
| |PDF (344 KB)

The authors describe the analysis of electromechanical transients in a large hydroelectric power plant interconnected via HVDC and AC links with two separate power systems. The investigation shows the dynamic behaviour of the total interconnected system on occurrence of faults in the HVDC and AC links. Special emphasis is given to the control of frequency deviations, damping of power swings and pr... View full abstract»

• ### SVC valve testing for UK transmission applications

Publication Year: 1991, Page(s):421 - 423
| |PDF (188 KB)

There are not at present, any internationally agreed testing standards for SVC valves; it was therefore necessary to agree a suitable testing programme which would verify that the electrical, thermal and mechanical performance requirements of the valve are satisfied under steady state and transient conditions. Many of the tests performed on an SVC valve are similar to those performed on other powe... View full abstract»

• ### Digital simulation of HVDC transmission and its correlation to simulator studies

Publication Year: 1991, Page(s):414 - 416
Cited by:  Papers (3)
| |PDF (160 KB)

In order to investigate the behaviour of HVDC transmission in a power system, suitable simulation models are required. A detailed commutation model with simulation of the thyristor bridges, while very precise, requires considerable time for calculation. Simplified models, on the other hand, do not always provide sufficiently accurate results. Simplified and detailed HVDC simulation models are desc... View full abstract»

• ### Design of frequency controller for Rihand-Dei hi HVDC Project

Publication Year: 1991, Page(s):273 - 278
Cited by:  Papers (1)
| |PDF (236 KB)

The Rihand-Delhi HVDC Project is an 814 km long bipolar transmission project. This system will be utilized for transmission of power from the coal fired thermal generation complex at Rihand and Singrauli to the National Capital Region around New Delhi. The scheme includes all the normal controllers typical for an KVDC transmission scheme. The higher level controls include a power modulation contro... View full abstract»

• ### Planning and design studies for the far North Queensland Georgetown and Normanton AC transmission scheme

Publication Year: 1991, Page(s):44 - 49
| |PDF (400 KB)

In Australia remote areas of Far North Queensland have relied for many years on small local diesel powered stations for electricity supply. This is about to change with the commencement of construction by the Far North Queensland Electricity Board (FNQEB) of a transmission line and substations to this region. Work is planned to be completed by mid 1992 . The authors describe planning studies for t... View full abstract»

• ### System performance and basic design aspects for the Etzenricht 600 MW back-to-back HVDC converter station

Publication Year: 1991, Page(s):171 - 176
| |PDF (344 KB)

The cooperation between Bavaria in Germany and Czechoslovakia in the area of energy exchange has been established for many years. This cooperation has been increased significantly, at the end of 1988 by an agreement for mutual energy assistance and electric energy exchange especially with regard to reduced air pollution. This exchange of energy will be carried out interconnecting both asynchronous... View full abstract»

• ### AC/DC system strength as indicated by short circuit ratios

Publication Year: 1991, Page(s):27 - 32
Cited by:  Papers (5)
| |PDF (400 KB)

Although from the very early HVDC schemes the designer had to contend with effects of weak' AC systems, a good understanding of the interactions between AC and DC systems has been established only over the last few years. The strength' of an AC system is represented by its impedance and its mechanical (rotational) inertia. System strength expressed as an absolute numerical value, such as short c... View full abstract»

• ### City versus country-a comparison of two types of standardised SVC for the National Grid in England

Publication Year: 1991, Page(s):248 - 254
| |PDF (500 KB)

The authors discuss the design and operational differences of static VAr compensators located in Exeter and St. John's Wood, London. Perhaps the most obvious and significant difference is the smaller site area available, which requires a more compact design of SVC. The concept of a walk-around site and independent maintainability of each main component with other equipment still live and in servic... View full abstract»

• ### A study of a ±500 kV, 2400 MW compact converter station

Publication Year: 1991, Page(s):153 - 158
| |PDF (432 KB)

For many years now Cigre has been collecting operating data on existing HVDC systems and periodically publishing updates of that material to the benefit of the entire industry. Recently a utility survey was made of HVDC projects operating worldwide. With the information on these additional important factors, the Cigre data will be more informative and provide increased practical value. This paper ... View full abstract»

• ### Review of the design of the James Bay-Boston DC system

Publication Year: 1991, Page(s):90 - 95
Cited by:  Papers (3)
| |PDF (332 KB)

The design of the James Bay-Boston 450 kV system is a reflection of the planning and operating requirements that led to its adoption and which in turn led to constraints in its implementation. The authors take a second look at this multiterminal DC (MTDC) system and review the planning studies, the operating philosophy and the design itself View full abstract»

• ### Operational and high voltage tests on thyristor valves for use in a standardized BB-system

Publication Year: 1991, Page(s):417 - 420
Cited by:  Papers (1)
| |PDF (252 KB)

A new valve design for HVDC BB-systems has been subjected to type tests based on the most stringent requirements from either one of the three documents presently available in the industry. All tests were passed successfully. There was no thyristor failure and the only capacitor failure was demonstrated to be caused by a manufacturing defect. Effects of the failure were limited to the particular th... View full abstract»

• ### HVDC tapping station: power tapping from a DC transmission line to a local AC network

Publication Year: 1991, Page(s):126 - 131
Cited by:  Papers (13)
| |PDF (344 KB)

The authors describe a new concept for tapping off a small amount of power from a high voltage direct current (HVDC) transmission line to a local network. The proposed new concept for a series tapping implies power conversion in two steps from the line to a local AC network. This will make it possible to the use a single phase transformer between the DC line potential and ground. The converter bri... View full abstract»

• ### Static VAR compensator from Coxipo Substation (Brazil)-comparison between computer simulations and field tests

Publication Year: 1991, Page(s):301 - 306
Cited by:  Papers (1)
| |PDF (292 KB)

The authors show a comparative analysis between field tests during commissioning of the static VAr Compensator (SVC) from Coxipo Substation (-50/+70 MVAr), and the computer simulations using a digital model developed by means of the EMTP (TACS) program. They also present some details of modelling of the SVC. The model is useful for: transient studies whenever the SVC is involved; the possibility o... View full abstract»

• ### Vector analysis and control of advanced static VAr compensators

Publication Year: 1991, Page(s):266 - 272
Cited by:  Papers (190)
| |PDF (348 KB)

The advanced static VAr compensator (ASVC) is based on the principle that a self-commutating static inverter can be connected between three-phase AC power lines and an energy-storage device, such as an inductor or capacitor, and controlled to draw mainly reactive current from the lines. This capability is analogous to that of the rotating synchronous condenser and it can be used in a similar way f... View full abstract»