Standardized retrofit of AC filter overload protection in Longquan-Zhengping HVDC transmission project

Abstract

The AC filter protection devices used in the Longquan-Zhengping HVDC transmission project are non-standardized products supplied by ABB in 2003. The AC filter overload protection for the project must be standardized through renovation. Through analysis of the protection architectures， protection principles， and protection settings of the unrenovated AC filter overload protection and the standardized AC filter overload protection， the differences between them in the protection architectures， implementation methods of skin effect coefficients， implementation methods of protection principle， and the expression form of protection settings are expounded. Moreover， the renovation method for standardizing AC filter overload protection is proposed. Finally， it is verified that the standardized AC filter overload protection can meet the demands of the project.

Keywords

• ac filter overload protection
• protection architecture
• protection principle
• protection settings
• skin effect coefficient