HIGH VOLTAGE DIRECT-CURRENT TRANSMISSION SYSTEM FOR A POWER STATION

• US 3,558,904 A
• Filed: 09/19/1968
• Issued: 01/26/1971
• Est. Priority Date: 09/26/1967
• Status: Expired due to Term

• Current Assignee: Kanngiesser Karl-Werner
• Original Assignee: Kanngiesser Karl-Werner
• Inventors: KANNGIESSER KARL-WERNER
• Application Number:
  US04/760,860
• Time in Patent Office: 859 Days
• US Class Current: 307/82
• CPC Class Codes: H02J 3/36 Arrangements for transfer of electric power between ac networks via a high-tension dc link
• CPC Class Codes: Y02E 60/60 Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Abstract

A high voltage direct current transmission system comprises a plurality of parallel arranged three-phase AC generators, a three-phase transformer connected to the output of each generator and a three-phase bridge type converter connected to the output of each transformer. The DC voltage outputs of the converters are connected in series and then fed over the transmission line system where they are then reconverted into AC. Each of the transformers includes a three-phase tertiary winding, and corresponding phases of the tertiary windings of these transformers are connected through power switches to a busbar, there being one such busbar assigned to each phase.

Claims

1. A high voltage direct current transmission system comprising a plurality of three-phase alternating current generators operating in parallel, a three-phase transformer individual to each said generator, each said transformer including three-phase primary, secondary and tertiary windings, a three-phase converter bridge individual to each said transformer, circuit means connecting said converter bridges in series on their direct current output sides, circuit means connecting each phase of the three-phase voltage output of each said generator with the corresponding phased primary winding of the transformer correlated therewith, circuit means connecting each phase of the secondary windings of each transformer with the corresponding phase of the converter bridge correlated therewith, a busbar individual to and correlated with each phase of said transformer, and circuit means individual to each phase of each of said threephase tertiary windings on said transformers and including a power switch for connecting corresponding phases of said tertiary windings to the busbar correlated therewith.

2. A high voltage direct current transmission system as defined in claim 1 wherein each generator forms a circuit block with its corresponding transformer and converter bridge.

3. A high voltage direct current transmission system as defined in claim 1 wherein the three-phase tertiary windings of each said transformer are connected in star.

4. A high voltage direct current transmission system as defined in claim 1 wherein the three-phase tertiary windings of each said transformer are connected in delta.

5. A high voltage direct current transmission system as defined in claim 1 wherein the three-phase tertiary windings of said trAnsformers are connected alternately in delta and in star, wherein the three-phase primary windings of each said transformer have the same type of connection and wherein the three-phase secondary windings of each said transformer have the same type of connection.

6. A high voltage direct current transmission system as defined in claim 5 wherein the three-phase primary windings of each said transformer are connected in delta and the three-phase secondary windings of each said transformer are connected in star.