The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 17, 2019
Filed:
Dec. 09, 2015
Nr Electric Co., Ltd., Nanjing, Jiangsu, CN;
Nr Engineering Co., Ltd., Nanjing, Jiangsu, CN;
Yunlong Dong, Jiangsu, CN;
Jie Tian, Jiangsu, CN;
Zhaoqing Hu, Jiangsu, CN;
Haiying Li, Jiangsu, CN;
Dongming Cao, Jiangsu, CN;
Haibin Liu, Jiangsu, CN;
Yu Lu, Jiangsu, CN;
NR Electric Co., Ltd., Nanjing, Jiangsu, CN;
NR Engineering Co., Ltd., Nanjing, Jiangsu, CN;
Abstract
The present invention discloses a passive islanding to grid-connection switching method for a VSC HVDC transmission system. When the VSC HVDC transmission system in an island operation state, whether the VSC HVDC transmission system enters an grid-connection state is determined by detecting whether an overcurrent phenomenon has occurred in a converter valve-side three-phase alternating-current or a converter bridge arm current, and detecting a change status of an alternating-current side voltage. The system is controlled to switch from an island operation control mode to a grid-connection control mode. At a moment of switching, the online control mode is smoothly switched to by changing a power instruction and performing phase tracking on a current grid voltage, so that continuous operation of the system is maintained.