SECTION A : 40 MARKS BAHAGIAN A : 40 MARKAH INSTRUCTION: This section consists of TEN (10) structured questions. Answer ALL questions. ARAHAN: Bahagian ini mengandungi SEPULUH (10) soalan berstruktur. Jawab SEMUA soalan. CLO1 C1 QUESTION 1 List FOUR (4) parameters with I-V Characteristic for SCR device. SOALAN 1 Senaraikan EMPAT (4) parameter dengan ciri I-V bagi peranti SCR. CLO1 QUESTION 2 Give TWO (2) differences between SCR and TRIAC. SOALAN 2 Berikan DUA (2) perbezaan antara SCR dan TRIAK. CLO1 QUESTION 3 Compare TWO (2) advantages between MOSFET and BJT. SOALAN 3 Bandingkan DUA(2) kelebihan di antara MOSFET dengan BJT. 2 SULIT
QUESTION 4 If a half-wave controlled rectifier has a purely resistive load of R = 10Ω, a firing angle α= 3 and an input voltage Vin RMS = 169 V, calculate: (i) the average output voltage, V o;avg (ii) the average output current, I o;avg SOALAN 4 Sekiranya satu penerus terkawal separuh gelombang mempunyai beban perintang R= 10Ω, sudut picuan α = 3 dan voltan masukan VinRMS = 169 V; kirakan: (i) Voltan keluaran purata, V o,purata (ii) Arus keluaran purata, I o,purata QUESTION 5 With reference to Figure A5, derive the equation for average output voltage, V o,avg. Given V in = V m sin wt. SOALAN 5 Merujuk kepada Rajah A5, terbitkan persamaan bagi voltan keluaran purata, V o,purata. Diberi V in = V m sin wt. Figure A5 / Rajah A5 QUESTION 6 Draw and label the circuit connection for the Three-Phase Half-Wave Controlled Rectifier with an inductive load. SOALAN 6 Lukis dan labelkan litar bagi Penerus Terkawal Separuh Gelombang Tiga Fasa dengan beban induktif. 3 SULIT
QUESTION 7 Calculate the operation frequency for a Buck Converter if t on is 4 ms, input voltage is 80 V and output voltage is 40 V. SOALAN 7 Kirakan frekuensi kendalian untuk Penukar Langkah Turun beroperasi jika t on 4 ms, voltan masukan ialah 80 V dan voltan keluaran ialah 40 V. QUESTION 8 Sketch and label the waveform of inductor current of Buck Converter for t on = 50 ms and t off = 20 ms. SOALAN 8 Lakar dan labelkan bentuk gelombang arus peraruh bagi Penukar Langkah Turun untuk t on = 50 ms dan t off = 20 ms. QUESTION 9 Describe TWO (2) disadvantages of Silicone Controlled Rectifier (SCR) in designing an inverter (DC to AC converter). SOALAN 9 Jelaskan DUA (2) kekurangan Silicone Controlled Rectifier (SCR) dalam rekabentuk sebuah penyongsang (Penukar AT ke AU). QUESTION 10 Sketch and label a single-phase full-bridge inverter circuit by using SCR. SOALAN 10 Lakar dan labelkan litar sebuah penyongsang tetimbang penuh satu fasa menggunakan SCR. 4 SULIT
SECTION B : 60 MARKS BAHAGIAN B : 60 MARKAH INSTRUCTION: This section consists of THREE (3) essay questions. Answer ALL questions. ARAHAN: Bahagian ini mengandungi TIGA (3) soalan esei. Jawab SEMUA soalan. QUESTION 1 SOALAN 1 Figure B1(a)/Rajah B1(a) CLO1 (a) Figure B1(a) shows the characteristic of semiconductor device used in rectifier. Based on the figure above, answer the following: Rajah B1(a) menunjukkan lengkuk ciri bagi peranti separuh pengalir yang digunakan di dalam penerus. Berdasarkan rajah diatas, jawab soalan berikut: (i) Name the device. Namakan peranti berkenaan. (ii) Sketch and label the symbol of the device Lukis dan labelkan simbol peranti berkenaan. [1 mark] [1 markah] [2 marks] [2 markah] 5 SULIT
(iii)identify the parameter A,B,C,D,E,F. Nyatakan parameter A,B,C,D,E,F. [3 marks] [3 markah] (iv) State TWO (2) methods of turning ON and TWO (2) methods of turning OFF the device. Nyatakan DUA (2) cara menghidupkan dan DUA (2) cara mematikan peranti berkenaan. Figure B1(b) /Rajah B1(b) (b) Figure B1(b) shows the schematic circuit of Single-Phase Controlled Half-Wave Rectifier with resistive and inductive load. Based on the figure above, answer the following: Rajah B1(b) menunjukkan litar skematik bagi Penerus Terkawal Separuh Gelombang Satu Fasa dengan beban perintang dan peraruh. Berdasarkan rajah diatas, jawab soalan berikut: (i) Explain the operation of the circuit. Terangkan operasi litar. (ii) Given V L =120sinωt, α=20º and β=30º, find the value of average output voltage. Diberi V L =120sinωt, α=20º dan β=30º, cari nilai bagi voltan keluaran purata. [6 marks] [6 markah] 6 SULIT
QUESTION 2 SOALAN 2 (a) Identify THREE (3) electronic components that can be used as a switch in the DC to DC converter. Kenalpasti TIGA (3) peranti elektronik yang dapat digunakan sebagai suis di dalam litar penukar AT ke AT. (b) Based on Figure B2(b): Berdasarkan Rajah B2(b): [3 marks] [3 markah] Figure B2(b)/Rajah B2(b) Prove that the formula of average output voltage for Boost converter is: Buktikan formula voltan keluaran bagi Penukar Langkah Naik adalah: V o Vs 1 D (c) Explain the principle operation of the circuit of Figure B2(b). Terangkan prinsip kendalian litar Rajah B2(b). [7 marks] [7 markah] [10 marks] [10 markah] 7 SULIT
QUESTION 3 SOALAN 3 C1 (a) Define the function of an inverter. Takrifkan fungsi penyongsang. [2 marks] [2 markah] (b) Figure B3(b) shows the circuit diagram of a single-phase half-bridge inverter with resistive load. Rajah B3(b) menunjukkan gambarajah litar bagi penyongsang tetimbang satu fasa dengan beban rintangan. Figure B3(b)/Rajah B3(b) (i) Explain the operation of the circuit above: Terangkan kendalian litar di atas: (a) During (0 < ωt < T/2) Semasa (0 < ωt < T/2) (b) During (T/2 < ωt < T) Semasa (T/2 < ωt < T) (ii) Illustrate the waveform of output voltage, V o and output current, I o. Gambarkan bentuk gelombang bagi voltan keluaran,v o dan arus keluaran, I o. 8 SULIT
(c) (i) Derive the mathematical equation for Root Mean Square (RMS) output voltage. Terbitkan persamaan matematik untuk voltan keluaran Punca Min Kuasa Dua (pmkd). [5 marks] [5 markah] (ii) Calculate the RMS output voltage and output current if the given Direct Current (DC) input voltage is 60V and the load resistance is 4Ω. Kira voltan keluaran dan arus keluaran pmkd jika voltan masukan Arus Terus (AT) yang diberikan adalah 60V dan rintangan beban adalah 4Ω. [5 marks] [5 markah].... SOALAN TAMAT 9 SULIT