SLIDE 1
Arno Smets
Equivalent Circuit
10 ‐10 ‐20 30 ‐40 10 ‐10 ‐20 30 ‐40 Voltage (V) Current Density (mAcm‐2) ‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Voc Jmp Pmax
Maximum power point Power Density (mWcm‐2)
Jsc Vmp
ID I IPH R
s
RSH V + _ ISH
Working Principle of a Semiconductor Based Solar Cell 3.1 Solar Cell - - PowerPoint PPT Presentation
Working Principle of a Semiconductor Based Solar Cell 3.1 Solar Cell - - PowerPoint PPT Presentation
Working Principle of a Semiconductor Based Solar Cell 3.1 Solar Cell Operation Week 3 Arno Smets Equivalent Circuit JV Curve V mp 10 10 Current Density (mAcm 2 ) R Power Density (mWcm 2 ) 0 0 I s V oc I D I SH + 10 10 P
SLIDE 2
SLIDE 3
pn Junction
‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐ ‐
p‐doped
+ + + + + + + + + + + +
n‐doped
SLIDE 4
Transport of Charge Carriers
E‐Field
SLIDE 5
pn Junction
- +
+ + + + + + + + + + + + + + + + + + +
n region p region E‐Field
SLIDE 6
pn Junction ‐ Reverse bias in the dark
- +
+ + + + + + + + + + + + + + + + + + +
n region p region Field increased
+
SLIDE 7
pn Junction ‐ Forward bias in the dark
- +
+ + + + + + + + + + + + + + + + + + +
n region p region Field reduced
- +
Net current!
SLIDE 8
pn Junction – Under illumination
- +
+ + + + + + + + + + + + + + + + + + +
n region p region E‐Field
SLIDE 9
Equivalent circuit of solar cell The dark current of the p‐n junction
ID V
SLIDE 10
Equivalent circuit of solar cell ‐ Reverse bias The dark current of the p‐n junction
ID V I Extemely small net current!
SLIDE 11
Equivalent circuit of solar cell ‐ Forward bias The dark current of the p‐n junction
ID V I Extemely small net current!
SLIDE 12
Voltage (V) Current Density (mAcm‐2)
10 ‐10 ‐20 ‐30 ‐40 ‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
SLIDE 13
10 ‐10 ‐20 ‐30 ‐40
Voltage (V) Current Density (mAcm‐2)
‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
+ + + + +
- +
+ + + + + + + + + + + + + +
- +
SLIDE 14
10 ‐10 ‐20 ‐30 ‐40
Voltage (V) Current Density (mAcm‐2)
‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
+ + + + +
- +
+ + + + + + + + + + + + + +
- +
SLIDE 15
Voltage (V) Current Density (mAcm‐2)
10 ‐10 ‐20 30 ‐40 ‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
IIDARK I0 exp qV kBT 1
SLIDE 16
Voltage (V) Current Density (mAcm‐2)
10 ‐10 ‐20 ‐30 ‐40 ‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
IIDARK I0 0 1
I0
SLIDE 17
Voltage (V) Current Density (mAcm‐2)
10 ‐10 ‐20 ‐30 ‐40 ‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
IIDARK I0 exp qV kBT 1
SLIDE 18
Voltage (V) Current Density (mAcm‐2)
10 ‐10 ‐20 ‐30 ‐40 ‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
Reverse Bias Forward Bias
IIDARK I0 exp qV kBT
SLIDE 19
V + _
Equivalent circuit of solar cell
ID I IPH
The illuminated ideal p‐n junction
SLIDE 20
10 ‐10 ‐20 ‐30 ‐40
Voltage (V) Current Density (mAcm‐2)
‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
drift currents light induced minority carriers
SLIDE 21
10 ‐10 ‐20 30 ‐40
Voltage (V) Current Density (mAcm‐2)
‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
- +
+ + + +
- +
+ + + + + + + + + + + + + +
SLIDE 22
10 ‐10 ‐20 30 ‐40
Voltage (V) Current Density (mAcm‐2)
‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
IIPH IDARK IPH I0 exp qV kBT 1
J I A
SLIDE 23
10 ‐10 ‐20 ‐30 ‐40
Voltage (V) Current Density (mAcm‐2)
‐0.2 0.0 0.2 0.4 0.6 0.8 1.0
JJPH JDARK JPH J0 exp qV kBT 1
J I A
SLIDE 24