High-speed disconnector using semiconductor technology

• US 6,229,228 B1
• Filed: 03/19/1999
• Issued: 05/08/2001
• Est. Priority Date: 03/20/1998
• Status: Expired due to Fees

• Current Assignee: Asea Brown Boveri AG (ABB Limited)
• Original Assignee: Asea Brown Boveri AG (ABB Limited)
• Inventors: Dahler, Peter, Gruning, Horst
• Primary Examiner(s): Fleming, Fritz
• Assistant Examiner(s): DeBeradinis, Robert L
• Application Number:
  US09/272,392
• Time in Patent Office: 781 Days
• Field of Search: 307/64, 307/43, 307/70, 307/80, 307/85, 307/86, 307/116, 307/125, 307/126, 307/414, 307/415, 327/438, 327/447
• US Class Current: 307/64
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems

Abstract

The invention specifies a disconnector for decoupling a load from a supplying AC power supply system. The disconnector comprises a transformer whose primary is connected into the AC power supply system. On the secondary side, a rectifier circuit is provided which has a turn-off thyristor connected to it. In normal operation, the turn-off thyristor is kept closed, so that the power supply system supplies the load. In the event of power supply system faults or interruptions, the turn-off thyristor is opened, which disconnects the power supply system from the load owing to the transformer impedance.

Claims

1. A high-speed disconnector for disconnecting a load (1) from a supplying AC power supply system (R, S, T), wherein the disconnector (12) comprises a transformer (3) whose primary is connected to the AC power supply system (R, S, T) and which has a turn-off thyristor (4) connected to its secondary via a rectifier circuit (9).

2. The disconnector as claimed in claim 1, wherein a series circuit made up of a diode (6) and a capacitor (5) is connected in parallel with the turn-off thyristor (4).

3. The disconnector as claimed in claim 1, wherein the turn-off thyristor (4) is hard-driven.

4. An uninterruptible power supply for a load (1) supplied by an AC power supply system (R, S, T), comprising a disconnector (12) for decoupling the load (1) from the AC power supply system, an auxiliary AC voltage source (2) and means (11) for coupling the auxiliary AC voltage to the load, wherein the disconnector (12) comprises a transformer (3) whose primary is connected to the AC power supply system (R, S, T) and which has a turn-off thyristor (4) connected to its secondary via a rectifier circuit (9).

5. The uninterruptible power supply as claimed in claim 4, wherein the auxiliary AC voltage source (2) is coupled to the load (1) by means of a further transformer (11), and wherein the auxiliary AC voltage source (2) comprises a DC voltage source (8, 9) which is converted to an AC voltage by means of a converter (7), the converter (7) having hard-driven turn-off thyristors.