With respect to a PV module's I-V and P-V curves, and the module's operating point, consider the following statements:
a) When the operating point of the PV module is on the MPP (maximum power point), \(P_{mpp} \lt V_{oc} \times I_{sc} \)
b) For a given Irradiance and Temperature condition, and a uniformly illuminated (all solar cells receive the same illumination) module with perfectly functional solar cells, there is one and only one MPP defined for the PV module.
c) Assume that a simple fixed load of pure resistance R is connected directly to the PV module, and no MPPT device is connected to this setup. Under such a scenario, the operating point of the PV module will always coincide with the MPP, irrespetive of the illumination conditions.
d) The curvature of the I-V characteristics of a module around the region of MPP can be looked upon as a result of the non ideal resistances of the solar cells that make up the module.
Which of the above statements are true?
1. a) only
2. a), c) and d)
3. All of a), b), c) and d)
4. a), b) and d)
5. a) and b)
Consider the following statements related to the field of MPPT Techniques.
a) The PV output is never steady at the MPP.
b) Inclusion of a pilot solar cell can improve the PV module's yield.
c) The hardware complexity is high for implementing this design.
d) The output of the PV module is maximum only if load resistance = \(\frac{V_{mpp}}{I_{mpp}}\).
Consider the following conditions at the PV output
i) An MPPT device implementing Fractional Open Circuit Voltage method
ii) An MPPT device implementing Incremental Conductance method
iii) No MPPT device connected; solar module directly connected to the load.
iv) An MPPT device implementing Perturb and observe method
Which of the following matches the statements a) through d) with the right PV output conditions in i) through iv)
1. a)-iv), b)-i), c)-iii), d)-ii).
2. a)-i), b)-iv), c)-ii), d)-iii).
3. a)-iv), b)-ii), c)-i), d)-ii).
4. a)-iv), b)-i), c)-ii), d)-iii).
1)4
2)4
sorry is not 1)a.
1)4
2)4
1)4
2)4
Formula in first question: a)Pmpp < Voc X Isc
Formula in second question: Load resistance = Vmpp/Impp
For the first set of statements:
a) When the operating point of the PV module is on the MPP (maximum power point), \(P_{mpp} \lt V_{oc} \times I_{sc} \)
To check the validity of this statement, we need to understand the I-V (current-voltage) and P-V (power-voltage) curves of a PV module. The MPP is the point on the curve where the power output of the module is maximized.
The power output of a PV module is given by \(P = V \times I\), where V is the voltage and I is the current. The open circuit voltage (\(V_{oc}\)) is the voltage across the PV module when no load is connected, and the short circuit current (\(I_{sc}\)) is the current flowing through the module when a load with zero resistance is connected.
The MPP occurs at a voltage (\(V_{mpp}\)) and current (\(I_{mpp}\)) where the product of these values, \(V_{mpp} \times I_{mpp}\), gives the maximum power output.
If \(P_{mpp} \lt V_{oc} \times I_{sc}\), then it means that the maximum power output of the module is less than the product of the open circuit voltage and short circuit current. This statement is not true in general, as the MPP should provide the maximum power output.
b) For a given Irradiance and Temperature condition, and a uniformly illuminated (all solar cells receive the same illumination) module with perfectly functional solar cells, there is one and only one MPP defined for the PV module.
To determine the validity of this statement, we need to consider the conditions for MPP. The MPP depends on various factors such as sunlight intensity, temperature, shading, and the load connected to the module.
In ideal conditions, with perfectly functional solar cells and uniform illumination, there would usually be one and only one MPP for a given irradiance and temperature condition. However, external factors like shading or non-uniform illumination could result in multiple MPPs. Therefore, this statement is not always true, although it holds under ideal circumstances.
c) Assume that a simple fixed load of pure resistance R is connected directly to the PV module, and no MPPT device is connected to this setup. Under such a scenario, the operating point of the PV module will always coincide with the MPP, irrespective of the illumination conditions.
To evaluate this statement, we need to understand the effect of the load on the PV module's operating point. When a load is connected to the module, the operating point shifts along the I-V curve based on the load resistance.
In general, for a fixed load of pure resistance R, the operating point of the PV module will not always coincide with the MPP. It depends on the relationship between the load resistance and the internal resistance of the PV module. If the load resistance is matched to the internal resistance of the module, the operating point can coincide with the MPP. However, this may not hold true for all illumination conditions.
d) The curvature of the I-V characteristics of a module around the region of MPP can be looked upon as a result of the non-ideal resistances of the solar cells that make up the module.
To verify this statement, we need to examine the I-V characteristics of a module around the MPP. The curvature of the I-V curve in this region is affected by various factors, including non-ideal resistances.
Non-ideal resistances such as series resistance and shunt resistance can cause the I-V curve to deviate from a perfect straight line. These resistances are present due to various factors like material imperfections, contact resistance, and parasitic effects. The existence of these non-ideal resistances contributes to the curvature of the I-V characteristics around the MPP.
Based on the explanations above, the correct answer is option 4. a), b), and d) are true statements regarding PV module's I-V and P-V curves, and the MPP.
For the second set of statements:
a) The PV output is never steady at the MPP.
This statement is true. The PV output is constantly changing due to variations in solar radiation, temperature, shading, and other external factors. Therefore, it is never steady at the MPP, which represents the maximum achievable power output.
b) Inclusion of a pilot solar cell can improve the PV module's yield.
This statement is false. The inclusion of a pilot solar cell does not directly improve the PV module's yield. A pilot solar cell, also known as a reference cell or sensor, is used in some MPPT (Maximum Power Point Tracking) techniques to measure the module's output and adjust the operating conditions to track the MPP. However, it does not directly impact the module's overall yield.
c) The hardware complexity is high for implementing this design.
This statement is subjective and depends on the specific MPPT technique and implementation. Some MPPT techniques require complex hardware and control algorithms, while others may be simpler to implement. Therefore, it is not accurate to make a general statement regarding the overall hardware complexity of MPPT designs.
d) The output of the PV module is maximum only if load resistance = \(\frac{V_{mpp}}{I_{mpp}}\).
This statement is true. The output power of a PV module is maximum when the load resistance matches the internal resistance of the module, which is equal to the ratio of \(V_{mpp}\) (voltage at MPP) to \(I_{mpp}\) (current at MPP). Therefore, the load resistance should ideally be set to this value to achieve maximum power output.
Based on the explanations above, the correct answer is option 2. a)-i), b)-iv), c)-ii), d)-iii).