Transcript Solar cell種類

太陽光發電系統介紹
Solar cell 篇
Motech Industries Inc.
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Solar cell 種類
種類
1.Crystalline silicon solar cell
A. Monocrystalline
B. Multicrystalline
2.Thin film solar cell
A. Amorphous silicon
B. Polycrystalline materals
C1. Cd Te
C2. Copper indium diselenide
(CIS or CIGS)
備註
88% Market
數百 microns
C-Si
12% Market
1 micron
a-Si (amorphous)
金屬與另一惰性金屬接觸
時所產生之電化腐蝕現象
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Solar Cell 製作
A. 將n-type摻雜，塗佈在p-type之表面。
B. 印刷導引線(光與電阻性損失最小) 最大光吸
收及電流收集。
Silica
(SiO2)
Mono
CZ
冶金級 silane
FZ 單晶矽晶碇
複晶矽
98%pure
10-9
高溫去氧化
拋光
電極網印
清洗
燒結
蝕刻
鍍錫
表面處理
P/N擴散
電漿蝕刻
切割
抗反射
模沈積
Solar Cell
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Solar cell 比較

矽
化合物
染料
Single
15~24
price
B
Multi
10~18
A
A
a-Si
8~13
A+
A
GaAs
19~32
B-
A+
CdTe
10~15
A
A
CuInSe2
10~12
A
A
TiO2
7~11
A+
B
2以下
A+
B-
有機半導體
信賴度
A+
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PV Module Performance Rating
 測試環境
1. The peak watt (Wp) rating
A. Temp
B. Solar radiation (AM1.5)
但如此實驗室的狀態不實際。
2. NOCT-normal operating cell temperature
在一定之室外溫度下所測得之最大功率，雖較
Wp 為低，但較真實。
3. AMPM standard
global-average day : light level, ambient
temperature, air mass
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Electrical Performance

1. Power Output：一天內產生之peak power or avg power。
(watts)
2. Energy Output：
(Wh)
A
B
C
Wh/m2 Wh/Kg Wh/$
在一定之週期下評估以上3項目
3. Conversion efficiency：
energy output from array
energy input from sun
x 100%
評價單位：1EEE、ASTM (American Society for Testing and Materials)
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影響日照的因素
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光波頻譜
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2ND Quadrant:
Generation
I
1ST Quadrant:
Dissipation
V
3D Quadrant:
4TH Quadrant:
Dissipation
Generation
Power is either generated or dissipated,
depending on the quadrant you are in.
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I
Power
Dissipating
Region
V
Power
Dissipating
Region
Dark Characteristic
I
V
Power
Generating
Region
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Light Characteristic
The VI characteristic of a solar cell is
usually displayed like this:
V
I
V
I
The coordinate system is flipped around the
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voltage axis.
Power is a function of position along the VI
characteristic. At the intercepts, it is
minimum - zero - increasing to a max near
the knee of the curve.
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Set #1: ISC , PMAX , VOC
ISC
(0V, 150 mA)
 V  I = 0 mW
PMAX
(0.43 V, 142 mA)
 V  I = 61 mW
Some typical
values
(0.5V, 0 mA)
 V  I = 0 mW
VOC
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The short circuit current ISC is a linear
function of sunlight intensity. The open
circuit voltage VOC is not. (VOC is weakly
dependent on temperature.) Recall from
Part I that sunlight intensity is measured
in terms of a solar constant with units
such as mW/cm2.
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Answer to Question #1:
I = ISC
R = 0
Does it surprise you that the current at
short circuit is not infinite? Or that a
current can flow with no voltage? Where
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does the energy originate?
Answer to Question #2:
I = 0
R = 
+
_
V = VOC
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Answer to Questions #3 and #4 (cont’d):
Current at max power
ISC
Hyperbola for P = PMAX
Point of tangency
Voltage at max power
VOC
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Set #2: RS , RSH
ISC
RSH
The slopes of
these lines are
characteristic
resistances.
RS
VOC
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Questions:
1. Which resistance is higher, the
measurement at ISC or the measurement at
VOC ?
Remember: R = V/I !
2. Physically, what do you think these
resistances represent?
3. As a solar cell designer, what is your
preferred ideal value?
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Answers to Questions #1 - #3:
The resistance at ISC is extremely high. In
an equivalent circuit model of a solar cell, it
represents a shunt resistance.
The resistance at VOC is extremely low. In
an equivalent circuit model of a solar cell, it
represents a series resistance.
Both of these resistances are internal, and
represent energy dissipation mechanisms in
the cell.
Ideally, a designer would like zero series
resistance and infinite shunt resistance.
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Cell
RS
ISC
RSH
RLOAD
Cell
Equivalent circuit for a solar cell with load.
Internal resistances RS and RSH represent
power loss mechanisms inside the cell. 21
RS = 0
ISC
RSH = 
RLOAD
The ideal solar cell would have no internal
losses at all! What would the VI
characteristic of THIS cell look like? 22
The Ideal Solar Cell
ISC
RSH = 
RS = 0
VOC
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The Ideal Solar Cell
ISC
Notice that the area under
the rectangle = PMAX for
the ideal cell. For this cell,
PMAX = VOC  ISC
VOC
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Set #3: Fill Factor
ISC
In fact, PMAX/(ISC  VOC)
measures the cell’s quality
as a power source. The
quantity is called the “Fill
Factor.” Can you see why?
VOC
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Questions:
1. What is the ideal fill factor?
2. Can the ideal cell ever be built? Why
or why not?
3. For a cell with these parameters:
(0V, 150mA), (0.43V, 142mA), and (0.5V,
0mA)
calculate the fill factor.
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Answer to Question #1:
The ideal fill factor is unity. Why?
Answer to Question #2:
An ideal cell might be approximated, but never
actually built. Nature is never ideal as humans
think about “ideal.”
Answer to Question #3:
The fill factor is:
(0.43V  142mA)/(0.5V  150mA) = 0.81 = 81%
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太陽光發電系統介紹
Inverter 篇
Motech Industries Inc.
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變流器技術

太陽光電池與電池產生直流電壓與電流，
然而負載所需為交流功率時，那麼就需
要Inverter來轉換DC/AC，一般來說可利
用Inverter轉換DC電源成為交流單/三相、
50/60Hz、117/220V，而轉換功率可從
數百Watts到數千KWatts，較大功率輸出
的Inverter其輸出電壓可達480V甚至更高。
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Inverter種類
種類
1. 獨立型
A. 弦波
B. 修正弦波
C. 方波
2.併聯型
A. 單一MPPT
B. 多個MPPT
3.混合型
備註
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變流器的功率額定



1.功率是時間的函數
2.突波功率
3.溫度對額定功率的影響
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變流器的效率



1.效率視負載而定
2.電感性對電阻性負載
3.效率測量的設定
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變流器的波形



1.方波
2.修正方波或修正弦波
3.弦波
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變流器電路




1.先變頻再變壓
2.先變壓再變頻
3.波寬調變
4.多工變壓器
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市電併聯混合型變流器



More flexibility on power management.
Provides limited power for critical loads
incase of power failure.
Requires Battery maintenance schedule.
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變流器特徵總合




AC OUTPUT PARAMETERS
DC INPUT PARAMETERS
PROTECTION
GENERAL SPECIFICATION
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AC OUTPUT PARAMETERS
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Output Voltage
Output Frequency
Continues AC output rating
Waveform
Output Power Factor
THD
DC control injection
Efficiency
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DC INPUT PARAMETERS


Input Power control
MPPT Range
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PROTECTION

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
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Internal Protection System
Anti islanding
Protection signals/contacts
Internal Shutdown
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GENERAL SPECIFICATION 1
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Parallel Operation
Local Operator Interface
Front Panel LCD Display
Computer Ports Isolation
Remote Access
Parameters Fault log
Communications
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GENERAL SPECIFICATION 2
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Output Date Files
Operating Temperature Rang
Humidity
Enclosure
Printed Circuit Boards
Standby Tare Losses
Noise
Aux. ADC Port
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選擇變流器特性之進一步探討





1.直流輸入電壓
2.電壓調整率
3.可服務性
4.臨界點調整
5.併聯成較大功率源
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選擇變流器特性之進一步探討
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