Title:
METHOD FOR MERGING NON-OPERATING STATION INTO OPERATING SYSTEM IN MULTI-TERMINAL FLEXIBLE DIRECT CURRENT TRANSMISSION SYSTEM
Document Type and Number:
WIPO Patent Application WO/2014/131373
Kind Code:
A1
Abstract:
Disclosed is a method for merging a non-operating station into an operating system in a multi-terminal flexible direct current (DC) transmission system. The method comprises the following: selecting STATCOM operation mode at a non-operating station; cutting off a bypass switch on the alternating current (AC) side and connecting a charging resistor to an AC line; closing an AC feed-in switch and, by means of the charging resistor, pre-charging the non-operating-station converter valve; closing the bypass switch upon completion of pre-charging; selecting a constant DC voltage control mode at the non-operating station so as to carry out unlocking; controlling the difference between the non-operating-station DC voltage value and the operating system direct voltage value such that said difference remains within an allowable range; closing a pole-connection device on the DC side of the converter of the non-operating station; and switching the non-operating station from STATCOM operation mode to a DC operation mode, whereupon the non-operating station is merged with the operating system. The method enables an operating station to continue operating and checks DC overcurrent and AC overcurrent produced as a result of a non-operating station connecting to a network, thereby enabling a non-operating station to safely and reliably connect to a network.
Inventors:
DONG YUNLONG (CN)
LI GANG (CN)
TIAN JIE (CN)
WANG NANNAN (CN)
LIU CHAO (CN)
LI GANG (CN)
TIAN JIE (CN)
WANG NANNAN (CN)
LIU CHAO (CN)
Application Number:
PCT/CN2014/075653
Publication Date:
September 04, 2014
Filing Date:
April 18, 2014
Export Citation:
Assignee:
NR ELECTRIC CO LTD (CN)
NR ENGINEERING CO LTD (CN)
NR ENGINEERING CO LTD (CN)
International Classes:
H02J3/36
Foreign References:
| CN103138281A | 2013-06-05 | |||
| CN101242087A | 2008-08-13 | |||
| CN201674227U | 2010-12-15 | |||
| CN102510050A | 2012-06-20 |
Other References:
ZHAO, WANJUN ET AL.: "Engineering Technology of High Voltage Direct Current Transmission", CHINA ELECTRIC POWER PRESS, 31 August 2004 (2004-08-31)
KONG, MING ET AL.: "Pre-charging Control Strategies of Modular Multilevel Converter for VSC-HVDC", POWER SYSTEM TECHNOLOGY, vol. 35, no. 11, 30 November 2011 (2011-11-30), pages 67 - 72
KONG, MING ET AL.: "Pre-charging Control Strategies of Modular Multilevel Converter for VSC-HVDC", POWER SYSTEM TECHNOLOGY, vol. 35, no. 11, 30 November 2011 (2011-11-30), pages 67 - 72
Attorney, Agent or Firm:
NANJING JINGWEI PATENT & TRADEMARK AGENCY CO., LTD (CN)
南京经纬专利商标代理有限公司 (CN)
南京经纬专利商标代理有限公司 (CN)
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