| 1. Attempt any FIVE of the following: |
|---|
| (a)Give the applications of IGBT. |
| (b) What is the need of UPS? |
| (c) Draw a neat circuit diagram of class F commutation. |
| (d) Define: |
| (i) Firing angle |
| (ii) Conduction angle |
| (e) How GTO is advantages over SCR? |
| (f) State the main difference between PUT & UJT. |
| (g) Write the function of Freewheeling diode. |
| 2.Attempt any THREE of the following: |
|---|
| (a) Describe triggering of SCR using UJT relaxation oscillator. |
| (b) Draw the I-V characteristics of power transistor. Show all regions. |
| (c) With neat circuit diagram explain working of emergency light system. |
| (d) Compare SCR & TRIAC (any four). |
| 3. Attempt any THREE of the following: |
|---|
| (a) Explain with neat circuit diagram operation of temperature controller using SCR. |
| (b) Draw the circuit diagram of class-D commutation & explain its working. |
| (c) With neat constructional diagram write operating principle of PUT. |
| (d) Explain with circuit diagram of 10 mid-point controlled rectifier with R-load. |
| 4.Attempt any THREE of the following: |
|---|
| (a) Draw a neat labelled I-V characteristics of SCR. |
| Define : |
| (i) Latching |
| (ii) Holding current |
| (b) Differentiate between Natural and Forced commutation (any four). |
| (c) Draw construction of IGBT. State any two applications of it. |
| (d) Explain with circuit diagram the working of 14 halfwave controlled rectifier with R-L load. |
| (e) Draw a suitable circuit to control the speed of the motor using TRIAC and also give its operation. |
| 5. Attempt any TWO of the following: |
|---|
| (a) Draw a structure of TRIAC with doping levels. Write operating principle and give two applications of it. |
| (b) Draw the circuit diagram & waveforms of class A commutation. Explain its working. |
| (c) Draw & explain the working of 10 mid-point controlled rectifier with RL-Load. Also Draw input-output waveforms of it. |
| 6. Attempt any TWO of the following: |
|---|
| (a) Draw a structure of TRIAC with doping levels. Write operating principle and give two applications of it. |
| (b) Draw the circuit diagram & waveforms of class A commutation. Explain its working. |
| (c) Draw & explain the working of 10 mid-point controlled rectifier with RL-Load. Also Draw input-output waveforms of it. |
| (a) Draw full bridge & half bridge configuration with common cathode. |
| (b) Explain working of AC circuit breaker using SCR with circuit diagram. |
| (c) Draw symbol & V-I characteristics of |
| (i) LASCR |
| (ii) DIAC & |
| (iii) TRIAC |