A New Protection Scheme for an SSSC in an MV Network by Using a Varistor and Thyristors

To control power flow and manage fault level in meshed MV networks, back-to-back voltage source converters (B2B-VSCs) are being used. However, their high cost relatively low efficiency of concerns. Partially rated series compensators, such as SSSCs or UPFCs, desired but come with the challenge protecting device during grid faults. Their potential use has been limited comparison fully converters. This paper proposes a new system topology including thyristor crowbars varistor to protect SSSC an network improve reliability flexibility operation. Using proposed method, time required for isolating compensator from is reduced at least 20 ms, corresponding interruption conventional circuit breakers, down 3 ?s worst case addition detection delay. The performance evaluated by simulation. A small-scale single-phase prototype operating 230 V/16 tested order demonstrate concept.