Optimized idling grid-connection strategy for synchronous condenser

Authors: JIANXIANG SHI, HEQING HUANG, TENG LIU, WEI MU, JIANFENG ZHAO

Abstract: The rise of large-scale HVDC transmission technology has introduced new requirements for dynamic reactive power compensation in power systems. The new generation of synchronous condensers is independent of grid voltage and does not need to be dragged by a coaxial prime mover, which can improve the dynamic reactive power compensation of the power grid. This new generation of synchronous condensers is dragged by the static frequency converter to a 105% rated speed, after which the static frequency converter logs out. In the process of idling, the excitation mode switching is completed and the unit is connected to the grid simultaneously. The synchronous device passively captures the connection-dot in the process of idling; as a result, increasing the grid-connection success rate and reducing the impact of grid connection become a pair of contradictions. In this paper, the boundary conditions of the new generation of synchronous condenser grid-connection systems are analyzed. These provide the basis for setting the synchronous device parameters. Furthermore, this paper proposes an optimized grid-connection strategy to ensure the new generation of synchronous condensers possesses good grid-connection characteristics.

Keywords: Direct current transmission, synchronous condenser, static frequency converter, synchronous device, idling grid-connection

Full Text: PDF