Patent ID: 11894684
Assignee: HITACHI ENERGY LTD
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A voltage source converter (VSC) system of a high-voltage direct current (HVDC) system, the VSC system comprising:
a plurality of line-commutated converter (LCC) transformers reused from an LCC HVDC system, each LCC transformer being operable to transform alternate current (AC) voltage, the LCC transformers including a plurality of tap changers reused from the LCC HVDC system and set such that the voltage output by each LCC transformer is lower than a maximum voltage that the LCC transformer is capable of outputting;
a plurality of VSC units coupled in series, each LCC transformer respectively coupled to a single converter unit of only the VSC type, each VSC unit operable to convert between the AC voltage and direct current (DC) voltage; and
a plurality of bypass breakers, each bypass breaker coupled in parallel with at least one of the VSC units and operable to be closed to bypass the at least one VSC unit.