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