Characterization of Semiconductor Detectors by DLTS by Prof

Characterization of Semiconductor Detectors by DLTS by Prof. Dr. Muhammad Asgahr Hashmi The Islamia University of Bahawalpur

Outline qpn junctions as radiation and particle detectors ■ Radiation-induced defects in semiconductors ■ The interaction of electron traps with electrons ■ Characterization of traps with DLTS ■ Worth to know about DLTS

Part-II Dual Axis Solar Tracking System

Arrangement of the Proposed Solar Tracking System

• Fuzzy logic based solar tracking system are designed and implemented to track sunlight with higher degree of accuracy by pointing the solar panel always towards the sun in most of the day time.

Fuzzy Logic Basics Fuzzy logic addresses such applications perfectly as it resembles human decision making with an ability to generate precise solutions from certain or approximate information. • Facial pattern recognition • Transmission systems • Unmanned drone/helicopter • Smart households like washing machines etc.

Block Diagram of Fuzzy Logic Based Solar Tracking System

Plot of M. F’s for O/P Variable, SM-2 “Vertical Motor Control” Plot of M. F’s for O/P Variable, SM-1 “Horizontal Motor Control”

Ranges and M. F. ’s Membership Function (MF) Ranges (Voltage) Region Occupied Most Left -6 to -4 1 More Left -6 to -2 1 -2 Little Left -4 to 0 2 -3 Balanced -2 to 2 3 -4 Little Right 0 to 4 4 -5 More Right 2 to 6 5 -6 Most Right 4 to 6 6

Complete Set of Rules for Solar Tracking System

A Situation - Example Input Variables Horizontal Position CH Vertical Position CV Input Voltage (u) 1. 25 2. 4 Values x=2 u=2. 5 x=2 u=4. 8 Region Selection Fuzzy Set Calculation 2≤x<4 Region-5 f 1=(4 - 2. 5)/2=0. 75 f 2=1 -f 1=1 -0. 75=0. 25 4≤x<6 Region-6 f 3 = (6 - 4. 8)/2=0. 6 f 4= 1 -f 3=1 -0. 6=0. 4 The symbol ^ presents the operation of “min-AND” b/w the corresponding values of M. F’s.

Rules Horizontal position CH Vertical position CV Horizontal Motor Control SM-1 Rotation(o) Vertical Motor Control SM-2 Rotation (o) 1. Little right More down Little C. W = 0. 66 More C. W= 0. 83 S 1 1. Little right Little C. W = 0. 66 Most C. W= 1. 0 S 2 1. More right More C. W = 0. 83 More C. W= 0. 83 S 3 1. More right More C. W = 0. 83 Most C. W = 1. 0 S 4 Most down More down Most down

i Ri Si Ri * Si 1 0. 66 0. 3960 2 0. 4 0. 66 0. 2640 3 0. 25 0. 83 0. 2075 4 0. 25 0. 83 0. 2075 ΣSi*Ri =1. 075; ΣSi*Ri ∕ ΣRi = 1. 075/1. 5= 0. 716 = 71. 6% for SM-1 motor in the clock wise rotation. i Ri Si Ri * Si 1 0. 6 0. 83 0. 498 2 0. 4 1. 0 0. 4 3 0. 25 0. 83 0. 207 4 0. 25 1. 0 0. 25 ΣSi*Ri =1. 3555; ΣSi*Ri ∕ ΣRi =1. 3555/1. 5=0. 9036 = 90. 36 % for SM-2 motor in the clockwise direction.

Fuzzy logic controller Four Input current values from the four “Light Dependent Resistors” installed on solar panel Two output values as the “Stepper Motor Speeds” for the alignment of the solar panel

MATLAB (Simulink) Results Overview

Specifications of the PV panel used Model No. TBP-1235 ISC 2. 25 A VOC 21. 2 V IMP 2. 06 A VMP 17 V PMIN 35 W NS (No. of cells) 36 Nominal irradiance at 25°C 1000

Output power with/without tracker Time of the day Total PV panel output values without tracker PV panel output values with tracker V(V) I (A) P(W) I(A) P(W) 7: 00 am 8: 00 am 9: 00 am 6. 47 8. 76 10. 33 0. 016 0. 067 0. 160 0. 103 0. 593 1. 658 8. 10 11. 44 11. 638 0. 103 0. 169 0. 285 0. 84 1. 942 3. 324 10: 00 am 12. 75 0. 192 2. 456 12. 03 0. 274 3. 307 11: 00 am 12. 39 0. 258 3. 201 11. 83 0. 288 3. 412 11: 30 am 12. 37 0. 262 3. 240 11. 85 0. 2885 3. 419 12: 00 pm 12. 75 0. 258 3. 29 11. 88 0. 2881 3. 423 1: 00 pm 12. 80 0. 244 3. 124 11. 83 2: 00 pm 12. 79 0. 239 3. 062 11. 70 3: 00 pm 12. 88 0. 233 3. 010 11. 76 0. 283 3. 342 4: 00 pm 12. 75 0. 141 1. 808 11. 96 0. 20 2. 397 5: 00 pm 12. 68 0. 101 1. 289 12. 09 0. 177 2. 152 6: 00 pm 12. 29 0. 085 1. 052 12. 09 0. 173 2. 104 7: 00 pm 9. 61 0. 034 0. 334 11. 76 0. 106 1. 259 161. 62 2. 29 28. 22 161. 95 0. 283 3. 36 0. 2885 3. 206 3. 377 37. 65

Efficiency of the system WITHOUT solar tracking system •

Efficiency of the system WITH solar tracking system •

Conclusion • The completed simulation of FIS (Fuzzy Inference System) in MATLAB is also verified in SIMULINK environment. • The efficiency of the solar panel increases reasonably by the use of dual axis solar tracking system. • The results confirm reliability of the system. The system is easily expandable to control several PV panels at the same time.

Thank You.