VSC-HVDC station with SSSC characteristics

Commercial installations of voltage-source converter-high voltage direct current (VSC-HVDC) are now in service as asynchronous link and as underwater/underground DC transmission. The research reported in his paper is directed to providing VSC-HVDC with synchronizing power and damping power so that after a transient the steady-state is reached in minimal time. Damping power is achieved by injecting incremental power which is proportional to the frequency deviation measured by a phase lock loop (PLL). Synchronizing power is achieved by: (a) introducing a delay in the power measurement and (b) by incorporating a static synchronous series compensation (SSSC) in the VSC-station. The effectiveness of both the synchronizing and damping power is demonstrated through digital simulations of a turbine-generator system which is connected to a VSC-HVDC station. It is shown that with the synchronizing power and damping power, recovery from the fault disturbance is very much faster.