A new implementation of network fault tolerant voltage source converter for HVDC transmissionsystem

Abstract

this paper presents Fault Tolerant Voltage Source Converter for HVDC transmission system based on a hybrid multilevel voltage source converter with ac-side cascaded H-bridge cells. The proposed converter offers a unique feature of dc fault blocking capability (ability to block power exchange between the ac and dc sides during the dc side faults, hence no current flows in converter switches), operational flexibility in terms of active and reactive power control, black start capability, in addition to improve ac fault ride through capability. In this paper,fourquadrantoperationandvoltagesupport,theacanddc fault ride-through capabilities of the proposed converter will be demonstrated.
Index Terms—AC and DC fault ride through capabilities; DC fault reverse blocking capability; hybrid multilevel converter with ac side cascaded H bridgecells