Home / Online Test / Thyristor Protection Questions and Answers Online Test Thyristor Protection Questions and Answers S Bharadwaj ReddyLeave a comment Thyristor Protection Questions and Answers Power Electronics Objective Questions & Answers 0% di/dt protection is provided to the thryistor by connecting an inductor in series with the load connecting an inductor in series with the gate connecting an inductor in parallel across the load connecting an inductor in parallel across the gate terminal 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 F.A.C.L.F & C.B Snubber circuits Shielded cables & twisted gate leads Correct! Wrong! - Continue >> dv/dt protection is provided to the SCR by connecting an inductor & resister in parallel with the device connecting an inductor in series with the load connecting a capacitor & resister in parallel with the device connecting a capacitor in parallel with the load Correct! Wrong! - Continue >> The thyristor has the following specifications Vs = 400 V (di/dt)max = 25 A/μsec Find the value of L 16 μH 8 μH 80 μH 160 μH Correct! Wrong! - Continue >> Thyristors are used in electronic crowbar protection circuits because it possesses high surge current capabilities voltage clamping properties high amp 2-sec rating less switching losses Correct! Wrong! - Continue >> The dv/dt protection is provided in order to avoid accidental turn-on of the device reduce the junction temperature avoiding sudden large voltage across the load limit the power loss 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 – et/τ) I(1 + e-t/τ) I(1 + e-t/τ) I(1 – e-t/τ) 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 >> The local hot spot formation in the cross-section of the SCR is avoided by using only R loads proper mounting of the SCR on heat sink reducing the junction temperature applying gate current nearer to the maximum gate current Correct! Wrong! - Continue >> Over-current protection in SCRs is achieved through the use of F.A.C.L.F & C.B. Snubber Circuits Zener diodes Varistors 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 !
