A thyristor-switched capacitor (TSC) is a type of equipment used for compensating reactive power in electrical power systems. It consists of a power capacitor connected in series with a bidirectional thyristor valve and, usually, a current limiting reactor (inductor). The thyristor switched capacitor is an important component. A TSC is usually a three-phase assembly, connected either in a delta or a star arrangement. Unlike the TCR, a TSC generates no and so requires no filtering. For this reason, some SVCs have been built with only. A TSC normally comprises three main items of equipment: the main capacitor bank, the thyristor valve and a current-limiting reactor, which is usually air-cored. Capacitor bankThe largest item of equipment in a TSC, the capacitor bank, is. • (SC) • • Alstom Grid homepage•, Siemens, Energy Sector homepage Unlike the TCR, the TSC is only ever operated fully on or fully off. An attempt to operate a TSC in "phase control" would result in the generation of very large amplitude resonant currents, leading to overheating of the capacitor bank and thyristor valve, and. Some TSCs have been built with the capacitor and inductor arranged not as a simple tuned LC circuit but rather as a damped filter. This type of arrangement is useful when the power system to which the TSC is connected contains significant levels of background.
