Flexible AC Transmission Using TSR
The project aims at achieving FACTS by using TSR (Thyristor Switch Reactance). It is done when there is very low or minor load at receiving end while charging the transmission line. Since the presence of low load, small current flows through transmission line therefore the shunt capacitance becomes more prominent. Due to this voltage amplification or Ferranti Effect occurs and the voltage at receiving end increases two times than the voltage at sending end. For this reason to compensate, shunt inductors are automatically connected across the transmission line.
The project requires an operational amplifier that generates lead time between zero voltage pulse and zero current pulse. This lead time is given to two interrupt pins of microcontroller of 8051 family. The programmed microcontroller then initiates shunt reactors for compensating the voltage. SCRs arranged in series interfaced with microcontroller through optical isolation are used for switching reactor.