Electric power conversion systems – Current conversion – Including automatic or integral protection means
Patent
1999-04-29
2000-07-04
Berhane, Adolf Deneke
Electric power conversion systems
Current conversion
Including automatic or integral protection means
363 54, H02H 700, H02H 7125
Patent
active
060847875
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a device for supervising different positions of a valve of a high voltage converter station located on high voltage potential level and having a plurality of valve units each having at least one semiconductor component of turn-on-type and, for each semiconductor component, a first control unit located on high voltage potential level and controlling the component, the first control units being connected to a valve control unit located on a low potential level through light conductors for communication between the valve control unit and the first control-units while separating them galvanically.
Such high voltage converter stations may, for example, be stations in plants for transmitting electric power through High Voltage Direct Current (HVDC) for converting direct voltage into alternating voltage, and vice versa. However, the invention is not restricted thereto, but is directed to supervising all types of high voltage converter stations, in which high voltage typically may be voltages within the range 10-500 kV. Each valve unit usually has a plurality of semiconductor components of turn-on-type connected in series, such as thyristors, IGBTs or the like, which are controlled simultaneously, so that they act as one single switch, and among which the voltage to be held by the valve unit in a turned-off-state of the semiconductor components is distributed, since they normally only can hold 1-10 kV each.
High powers are handled by such a high voltage converter station and consequently, a failure of parts of, as of the entire station during a certain period of time generates high costs. Thus, it is an important goal to be able to supervise different positions of the valve so as to be able to take necessary measures, upon deviations from its normal state, for avoiding unplanned operation interruptions to the extent possible and to minimize the shutdown times for maintenance, by receiving information about exactly which components have a defect. Information about components with incipient deviations but not yet defective is also of interest for the foregoing reason, since corrective measures may be timely planned.
However, the different a fore-mentioned positions are located on a high voltage potential level, which makes the supervision thereof difficult, so that the way of proceeding has, until now, with respect to most of the positions, been restricted to carrying out a measurement of a parameter associated with the position in question on ground potential level, so as to then calculate a probable value of the parameter on high voltage potential level. An example of such a parameter is the temperature of the cooling water passing the semiconductor components for cooling thereof, in which this temperature has been determined indirectly by measuring the temperature of a cooling loop of the cooling system located on ground potential level, so as to calculate the temperature of the cooling water in the valve in question therefrom. It is natural that the accuracy will not be an optimum and that there are sources of faults making it possible to obtain values not at all corresponding to the reality. Furthermore, the determination is very inaccurate, since, for example, a very increased temperature of a single semiconductor component may not be determined, since this high temperature will have a minor influence upon the temperature of the cooling liquid in the loop on ground potential level.
It is also already known to supervise the very firing of the semiconductor component by sending an indication signal back from the first control unit through the light conductor to the valve control unit so as to indicate that the forward voltage across the semiconductor component is sufficient for a turning-on under favorable conditions. It is also already known to send a firing signal at one point of time to only one thyristor of a valve unit having a plurality of thyristors connected in series, and after that study the point of time for the arrival of the following indicati
REFERENCES:
patent: 5452196 (1995-09-01), Itoh
patent: 5521526 (1996-05-01), Nyberg et al.
patent: 5684465 (1997-11-01), Andersson et al.
Abstract of JP 58-51769 A (Kansai Denriyoku K.K.), vol. 7, No. 136, Mar. 16, 1983.
Abstract of JP 57-91543A (Toshiba Corp.), Jul. 6, 1982.
Asplund Gunnar
Bjorklund Hans
Nyberg Krister
Siljestrom Roland
strom Urban
ABB AB
Berhane Adolf Deneke
Patel Rajnikant B.
LandOfFree
Device for supervising in a high voltage converter station does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for supervising in a high voltage converter station, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for supervising in a high voltage converter station will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1492302