Thyristor Controlled Reactors are extensively used in dynamic VAR compensation applications such as Static Var Compensation (SVC). A thyristor-controlled reactor (TCR) is connected in series with a bidirectional.
Reactors > Facts/HVDC
Thyristor Controlled Reactor
TCRs are essentially shunt reactors where current is continuously regulated by thyristor valves. The three phase reactors are delta connected and each phase is split into two coils, while thyristors are connected between the coils. Changing the trigger angle of a thyristor alters its admittance which varies fundamental current and thereby varying reactive power absorbed by the reactor.
The capacitor provides fixed compensation for the reactive power in SVC, while TCRs can absorb continuously controlled reactive power with a lagging power factor. SVCs thus expand the dynamic compensation range with both lagging and leasing power factors.
Static VAR compensation system using Thyristor controlled reactors can take care of PF correction, voltage variation, flicker compensation, harmonic suppression, and containing oscillations etc.
Reactor current can be controlled in a continuous manner from zero – if the switch is turned off – to its maximum value, when the reactor is directly connected to the source.