Hi everyone.
Welcome back to BP Solar energy course.
Today is his thrall.
I would like to discuss with you say effect of a parameter of great importance which is the team preacher.
First I would like to answer the standard question which is a greater team preacher better for the B
the output or is the V output independent of temperature changes in this graph.
You see Z Ivy curve of the V module at a given her audience as a temperature as shown intellect curve
is in miniature increase away the radius is constant.
We see only curve Z and not like the right to so we see is that why is a cut up has very increased.
There is a significant drop in voltage this mean that it over all power has been decreased.
On the other hand is that in preacher with two degrees.
With respect to original condition a Y and Z radius were a cornerstone ZBB output would show an increase
the minute increase in current wisdom.
Richer can be explained with the fact that current concentration and mobility increase is the semiconductor
wisdom bridge.
This is consistent with our basic understanding that semiconductor unlike regular conductor except better
conductivity with increasing compression and is a perfect isolated and absolute temperature of zero
code is indeed pleasing effect on voltage can be explained from this four of the basic diet equation
which have been seen Ellen
the open circuit is equal to in times hold this man constant times in pressure over a charge of electron
times Len both to tide over saturated current or like a second lost one or was it in breach of affects
and various term in this equation the net effect of the preacher is that it decrease that open circuit
voltage linearly the drop in open circuit voltage wisdom pressure is mainly referred to the increase
in the linkage linkage Carter or Ford to die which is all in the dog wisdom preacher
because I would strongly depend on to Richard the magnitude of reduction varies inversely with open
circuit voltage.
This mean zat cells with higher open circuit voltage are less affected pointing preachers and cells
with lower open circuit voltage this mean zap saw certain based on syllable with of certain voltage
of all points six five fold will it be more affected Zen a silicone with open circuit voltage off all
point is five fold.
So now you have an idea of effective in breach of UN be the outcome but how do we qualify as this effect
is it in breach of module we have to increase by 10 degrees Celsius.
How would that all of the Be Affected Web.
First of all the beating module manufacturer include what is known as temperature coefficient in that
the sheet of Z commercial modules in breach of coefficient which is the X by DTA is.
But a rate of change of parameter X with in for a second to appreciate coefficient the voltage is the
rate of change of the voltage wisdom breach similarly set in breach of coefficient of power is the rate
of change of out the bar with immigration a difficult date the shift of conversion BD module specifies
that preacher coefficient force the pole for certain voltage and short circuit current under EDC condition
as shown is the left to figure
given this coefficient how do we calculate the b v output with respect to temperature change we can
use this simple equation which is x of T is equal to x at the standard condition allows us to reach
a coefficient.
Times Z.
Ambient temperature minus is standard to.
X maybe so all the circuit voltage or short circuit column or evens the pole.
Z Turner D S by D d do needs to reach your coefficient.
Also particle parameters.
Z reference temperature taken for this calculation is that is DC temperature which is twenty five degrees
ladies
let's take a look at an example is the maximum power output of a dean will go under is the seed is to
one hundred and fifty.
What is the temperature coefficient of both is negative to what they are.
Degrees loses then Zen module.
Power output of often creatures 30 degree can be calculated as full to 150 what loss.
Minus two times serve T minus 25 well again zap out the board equal to two hundred and forty.
What.
As you can see a sign of the temperature or fiction that your mind as a parameter is increasing or decreasing
with compression.
Now we must be careful while making this calculation it is a previous example.
When he said that preacher will certainly decrease laces it will mean that B V modules temperature or
the NBN to bridge or should that to be the same.
As it turns out the module temperature or the silting preacher Zeb pool or turn NZ literature can d
y difference from the ambient temperature.
Let's see.
Why should be a difference between some wonderful temperature and ambient temperature.
Zepp could be several factor impacting the heat flow in and out of the modules encapsulation of solar
or Sun is the measure of factor increasing of the operating temperature of the easy money.
The eventual operating temperature of the module will be a result of this certain equilibrium between
heat generated by the module and the heat loss to surrounding environment the heat exchange with the
environment in turn could depend so on several factors like ambient temperature wind speed heat transfer
coefficient between the module and the environment.
And certainly conductivity of the modules as well Zen.
How do we estimate Z module temperature.
Based on the ambient temperature.
If we have to dig it down for so many factors
fortunately there is a model provided in literature.
Z get responsible is to meet Z module temperature as a function of the M.B.A. Bridge as the self temperature
is equal to ambient temperature boss error ideation times coefficient cold in 0 C D minus twenty over
eight hundred.
This model is sometimes called the N O C D model due to the use of knowing and operating seldom preacher
or in the city of said b the same or muddy means the end OCD OCD in this equation is the nominal operating
self to preach in the home city is the team preacher attend boys MTV sail under and there are gradients
of 800 watt been Mitre Square with a nominal wind speed of one meter per second
and is the ambient temperature is equal to to any degrees loses few G is the province as in instance
with the ambient temperature is that CMB Zumwalt who gives a corresponding symptom preacher SDL as can
be seen from this equation the certain preacher isn't the only function of the ambient temperature but
also as a function of radians.
This makes things more interesting because if we consider that it radians as it's in breach or change
over the Clinton years we would see effect of both the radius and temperature across this is in this
graph which has been made using the actual ambient temperature and radians data as seen in Zen these
are land in Z year off 2012 that corals funding certain creature have been calculated using the N O
C T Model.
This graph out of line the main reference from the N O C T model.
Now you are aware of Z sifting preacher and the difference between it and the ambient temperature and
you know said that ambient temperature is the air temperature but this is seldom pretty shook is the
module to breach so see you in the next section where we are going to discuss that diet or b system
wizardry it's great connected or stand alone we ve system so see you in the next step block.