Device for supervising in a high voltage converter station

• US 6,084,787 A
• Filed: 04/29/1999
• Issued: 07/04/2000
• Est. Priority Date: 06/11/1997
• Status: Expired due to Term

• Current Assignee: ABB AB (ABB Limited)
• Original Assignee: ABB AB (ABB Limited)
• Inventors: strom, Urban, Asplund, Gunnar, Bjorklund, Hans, Nyberg, Krister, Siljestrom, Roland
• Primary Examiner(s): Berhane, Adolf Deneke
• Assistant Examiner(s): Patel, Rajnikant B.
• Application Number:
  US09/230,947
• Time in Patent Office: 432 Days
• Field of Search: 363/51, 363/54, 363/57, 363/96, 363/133, 363/85, 324/765, 340/660
• US Class Current: 363/51
• CPC Class Codes: H02H 1/0069 by means of light or heat rays
• CPC Class Codes: H02H 7/1206 specially adapted to conversion cells composed of a plurality of parallel or serial connected elements
• CPC Class Codes: H02M 1/092 the control signals being transmitted optically

Abstract

A device for supervising different positions of a valve of a high voltage converter station located on a high voltage potential level comprises members arranged on a high voltage potential level and adapted to detect function parameters of the valve on a high voltage potential level and send values detected thereby to first control units for controlling the semiconductor components of the valve. The first control units have devices for processing the detected values and the first control units are adapted to utilize light conductors running back therefrom to a valve control unit for sending data resulting from the processing to an arrangement for supervising the valve located on a low potential level.

Claims

1. A device for supervising different positions of a valve of a high voltage converter station located on a 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 a high voltage potential level and controlling the component, said 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, said device comprising members arranged on a high voltage potential level and adapted to detect function parameters of the valve on a high voltage potential level and to send values detected thereby to said first control units, the first control units having means for processing said detected valves, and the first control units being adapted to utilize light conductors running back therefrom to the valve control unit to send data resulting from said processing to an arrangement for supervising said valve located on low potential level;

wherein said semiconductor components are arranged in stacks and shelf-like shields are arranged between semiconductor components superimposed for preventing a transfer of fire between said semiconductor components, and wherein an arrangement is arranged for circulating a cooling liquid passing the semiconductor components for cooling thereof, wherein said fire shields are designed to trap cooling liquid possibly leaking from said cooling arrangement, and members are arranged at least some of the fire shields to detect cooling liquid received thereon and to send information related thereto to the first control unit in question so as to send, after processing, data concerning the leakage of the cooling system indicated further to the supervising arrangement of the valve.

2. A device according to claim 1, wherein the fire shields have a recess with a small surface with respect to the surface of the fire shield for conducting cooling liquid trapped by the fire shield down thereinto, and said member is formed by a level indicator arranged in said recess and adapted to send a signal indicating a leakage to the respective first control unit when cooling liquid collected in the recess reaches a predetermined level.

3. A device according to claim 1, wherein said cooling liquid is water.

4. A device according to claim 1, wherein each fire shield of the valve is provided with members for detecting cooling liquid received on the shield.

5. 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 a high voltage potential level and controlling the component, said 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, said device comprising members arranged on a high voltage potential level and adapted to detect function parameters of the valve on a high voltage potential level and to send values detected thereby to said first control units, the first control units having means for processing said detected values, and the first control units being adapted to utilize light conductors running back therefrom to the valve control unit to send data resulting from said processing to an arrangement for supervising said valve located on low potential level;

and

wherein the valve includes an arrangement for cooling said semiconductor components with a cooling block associated with the respective semiconductor component and arranged to absorb heat from the semiconductor component and to transfer heat to a cooling medium, and wherein the device comprises temperature detecting members arranged at at at least some of said cooling blocks and adapted to send values detected thereby to the first control unit associated with the respective semiconductor component for elaborating and transmitting data concerning the temperature of said cooling block to said supervising arrangement.

6. A device according to claim 5, wherein said temperature detecting members are arranged in each cooling block for temperature detection at each said semiconductor component of the valve.

7. A device for supervising different positions of a valve of a high voltage converter station located on a 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 a high voltage potential level and controlling the component, said 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, said device comprising members arranged on a high voltage potential level and adapted to detect function parameters of the valve on a high voltage potential level and to send values detected thereby to said first control units, the first control units having means for processing said values detected, and the first control units being adapted to utilize light conductors running back therefrom to the valve control unit to send data resulting from said processing to an arrangement for supervising said valve located on low potential level;

and

wherein said valve is of line commutated type and said semiconductor components are thyristors, and wherein a voltage divider circuit consisting of resistances and capacitors is connected across each thyristor, the capacitors of the voltage divider being of a self-healing type, and the capacitance decreases gradually as of the point of time for occurring of a possible defect thereof, wherein the first control unit associated with the respective thyristor is arranged to register the voltage across the thyristor through a first member through a first resistance of the voltage divider at an instant immediately before the turning-on of the thyristor and thereby short-circuiting of the capacitor of the voltage divider, and through a second member register the voltage across a second resistance in the voltage divider circuit at a given point of time after said instant, said means being adapted to calculate a value of the capacitance of the capacitor of the voltage divider on the basis of said values of the two voltages and to send information depending thereupon through said light conductors to a supervising arrangement, and wherein said members are adapted to compare said capacitance value with a rated value of said capacitance and the supervising arrangement is arranged to determine whether a fault has occurred in the voltage divider on the basis of the comparison.

8. A device according to claim 7, wherein said first member is adapted to register said voltage at a given instant corresponding to the point of time for the turning-on of the thyristor in question through the first control unit associated therewith.