Consider a phase $$-$$ controlled converter shown in figure The thyristor is fired at an angle $$\alpha $$ in every positive half cycle of the input voltage. If the peak value of the instantaneous output voltage equals $$230$$ $$V,$$ the firing angle $$\alpha $$ is close to

High Voltage DC (HVDC) transmission is mainly used for

At a $$220$$ kV substation of a power system, it is given that the three-phase fault level is $$4000$$ MVA and single-line to ground fault level is $$5000$$ MVA. Neglecting the resistance and the shunt susceptances of the system.

The positive sequence driving point reactance at the bus is

The p.u. parameters for a $$500$$ MVA machine on its own base are:
Inertia, M = $$20$$ p.u.; reactance X = $$2$$ p.u. The p.u. values of inertia and reactance on $$100$$ MVA common base, respectively are