Online TestThyristor Protection Questions and Answers Thyristor Protection Questions and Answers Power Electronics Objective Questions & Answers 0% The local hot spot formation in the cross-section of the SCR is avoided by applying gate current nearer to the maximum gate current proper mounting of the SCR on heat sink using only R loads reducing the junction temperature Correct!Wrong!- Continue >> di/dt protection is provided to the thryistor by connecting an inductor in parallel across the load connecting an inductor in parallel across the gate terminal connecting an inductor in series with the load connecting an inductor in series with the gate Correct!Wrong!- Continue >> dv/dt protection is provided to the SCR by connecting a capacitor & resister in parallel with the device connecting an inductor in series with the load connecting a capacitor in parallel with the load connecting an inductor & resister in parallel with the device Correct!Wrong!- Continue >> Thyristors are used in electronic crowbar protection circuits because it possesses high amp 2-sec rating voltage clamping properties less switching losses high surge current capabilities Correct!Wrong!- Continue >> The dv/dt protection is provided in order to avoiding sudden large voltage across the load reduce the junction temperature avoid accidental turn-on of the device limit the power loss Correct!Wrong!- Continue >> False triggering of the SCRs by varying flux & noise is avoided by using di/dt inductor in series with the gate terminal Shielded cables & twisted gate leads Snubber circuits F.A.C.L.F & C.B Correct!Wrong!- Continue >> The effect of over-voltages on SCR are minimized by using RL circuits Varistors Circuit breakers di/dt inductor Correct!Wrong!- Continue >> Figure below shows SCR having dv/dt and di/dt protection, when the switch(shown in green) is closed the current through Rl = I(1 + e-t/τ) I(1 – et/τ) I(1 + e-t/τ) I(1 – e-t/τ) Correct!Wrong!- Continue >> Over-current protection in SCRs is achieved through the use of Varistors F.A.C.L.F & C.B. Zener diodes Snubber Circuits Correct!Wrong!- Continue >> The thyristor has the following specifications Vs = 400 V (di/dt)max = 25 A/μsec Find the value of L 160 μH 8 μH 80 μH 16 μH Correct!Wrong!- Continue >> Share the quiz to show your results ! Facebook Facebook Just tell us who you are to view your results ! Show my results >> Thyristor Protection I got %%score%% of %%total%% right Share your results Facebook Facebook Twitter Google+ ↺ PLAY AGAIN ! Share With Your Friends Facebook Twitter LinkedIn Pinterest Email WhatsApp
