The invention provides a flexible
direct current power transmission converter performance testing platform and a control method thereof. The
direct current side of a first modularized multi-
level converter and the
direct current side of a second modularized multi-
level converter are connected in a back-to-back mode, and three phases of the
alternating current side of the first modularized multi-
level converter are connected with three phases of the
alternating current side of the second modularized multi-level converter correspondingly, so that a power circulation pathway is formed; a
test power source is in parallel connection with the direct current side of the first modularized multi-level converter and the direct current side of the second modularized multi-level converter and provides loss power for steady-state operation testing; a
short circuit generator is in parallel connection with the direct current side of the first modularized multi-level converter and the direct current side of the second modularized multi-level converter. According to the testing platform and the control method thereof, the requirement for
power grid capacity is low; meanwhile, the direct current side power supply mode is adopted in the testing platform, and therefore the
single test power source is adopted for the whole platform. With regard to test items of the
short circuit and over-current turn-off required by
IEC standards, due to the fact that the basic structure of the platform is basically the same with that of practical
engineering, the
short circuit test and the over-current turn-off test can be set through the platform according to double-pole short-circuit faults in a practical flexible direct current
power transmission system.