Solar panel model with MPPT in Simulink - Step-by-Step Execution

Concept Flow - Solar panel model with MPPT

Start Simulation

↓

Solar Panel Model

↓

Measure Voltage & Current

↓

Calculate Power

↓

MPPT Algorithm

↓

Adjust Operating Point

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Update Solar Panel Output

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Loop until steady state or end

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End Simulation

The simulation starts with the solar panel model producing voltage and current. The MPPT algorithm measures power and adjusts the operating point to maximize power output, looping until steady state.

Execution Sample

Simulink

1. Initialize solar panel parameters
2. Measure voltage (V) and current (I)
3. Calculate power P = V * I
4. Use MPPT to find max power point
5. Adjust voltage to maximize power
6. Repeat steps 2-5 until stable

This code simulates the solar panel output and uses MPPT to find and maintain the maximum power point.

Execution Table

Step	Voltage (V)	Current (I)	Power (P=V*I)	MPPT Action	Operating Voltage Adjusted
1	18.0	5.0	90.0	Measure initial power	No
2	18.5	5.1	94.35	Increase voltage	Yes
3	19.0	5.0	95.0	Increase voltage	Yes
4	19.5	4.8	93.6	Decrease voltage	Yes
5	19.2	4.9	94.08	Fine tune voltage	Yes
6	19.3	4.95	95.535	Stable at max power	No
7	19.3	4.95	95.535	No change, steady state	No

💡 MPPT converged to max power point at step 6, no further voltage adjustment needed.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	After Step 5	After Step 6	Final
Voltage (V)	18.0	18.0	18.5	19.0	19.5	19.2	19.3	19.3
Current (I)	5.0	5.0	5.1	5.0	4.8	4.9	4.95	4.95
Power (P)	90.0	90.0	94.35	95.0	93.6	94.08	95.535	95.535
MPPT Action	None	Measure initial power	Increase voltage	Increase voltage	Decrease voltage	Fine tune voltage	Stable at max power	No change

Key Moments - 3 Insights

Why does the MPPT algorithm sometimes decrease the voltage after increasing it?

Because after increasing voltage, the power decreased (step 4), so MPPT decreases voltage to find the maximum power point, as shown in execution_table rows 3 and 4.

Why does the power not always increase when voltage increases?

Power depends on both voltage and current. Increasing voltage can reduce current, lowering power. This is seen at step 4 where voltage increased but power dropped.

When does the MPPT algorithm stop adjusting voltage?

It stops when power stabilizes at maximum, shown at steps 6 and 7 where voltage and power remain constant.

Visual Quiz - 3 Questions

Look at the execution table, what is the power at step 3?

A 93.6

B 94.35

C 95.0

D 90.0

💡 Hint

Check the 'Power (P=V*I)' column at row with Step 3.

At which step does the MPPT algorithm first decrease the voltage?

A Step 4

B Step 3

C Step 2

D Step 5

💡 Hint

Look at the 'MPPT Action' column for the first 'Decrease voltage' entry.

If the current stayed constant at 5.0 A, how would power change from step 2 to step 3?

A Power would decrease

B Power would increase

C Power would stay the same

D Power would be zero

💡 Hint

Power = Voltage * Current; if current is constant and voltage increases, power increases.

Concept Snapshot

Solar panel model with MPPT:
- Measure voltage and current
- Calculate power = V * I
- MPPT adjusts voltage to maximize power
- Loop until power stabilizes
- MPPT finds max power point dynamically

Full Transcript

This visual execution traces a solar panel model using MPPT (Maximum Power Point Tracking). The simulation starts by measuring voltage and current from the solar panel. Power is calculated as voltage times current. The MPPT algorithm adjusts the voltage to find the point where power is highest. Sometimes increasing voltage reduces current, so power can drop, causing MPPT to decrease voltage. This process repeats until power stabilizes at maximum. The execution table shows step-by-step voltage, current, power, and MPPT actions. Variable tracker shows how values change over time. Key moments clarify why MPPT sometimes decreases voltage and when it stops adjusting. The quiz tests understanding of power values and MPPT decisions. This helps beginners see how MPPT works in a solar panel simulation.

Practice

1. What is the main purpose of the MPPT (Maximum Power Point Tracking) in a solar panel model in Simulink?

easy

A. To find the voltage and current that produce the maximum power output

B. To store energy in batteries

C. To convert DC to AC power

D. To measure sunlight intensity

Solution

1. Step 1: Understand MPPT function

   MPPT is designed to find the best operating point where the solar panel produces maximum power.

2. Step 2: Identify MPPT role in Simulink model

   In Simulink, MPPT adjusts voltage and current to maximize power output from the solar panel.

3. Final Answer:

   To find the voltage and current that produce the maximum power output -> Option A

4. Quick Check:

   MPPT = Max power point finder [OK]

Hint: MPPT always finds max power point, not storage or conversion [OK]

Common Mistakes:

• Confusing MPPT with battery storage
• Thinking MPPT converts power types
• Assuming MPPT measures sunlight only

2. Which Simulink block is typically used to represent the solar panel in a solar panel model with MPPT?

easy

A. Scope block

B. Battery block

C. DC-DC Converter block

D. PV Array block

Solution

1. Step 1: Identify solar panel representation

   The PV Array block models the photovoltaic solar panel's electrical behavior in Simulink.

2. Step 2: Differentiate other blocks

   Battery stores energy, DC-DC Converter changes voltage, Scope displays signals, so they are not solar panels.

3. Final Answer:

   PV Array block -> Option D

4. Quick Check:

   Solar panel = PV Array block [OK]

Hint: Solar panel block is called PV Array in Simulink [OK]

Common Mistakes:

• Choosing Battery block instead of PV Array
• Confusing Scope block as a model block
• Selecting DC-DC Converter as solar panel

3. Given this Simulink model snippet for MPPT control:

V = 30; I = 5;
P = V * I;
if P > P_prev
  V_ref = V + 0.1;
else
  V_ref = V - 0.1;
end
P_prev = P;

What is the value of V_ref after running this code if P_prev was 140 before execution?

medium

A. 140

B. 29.9

C. 30.1

D. 30

Solution

1. Step 1: Calculate current power P

   P = V * I = 30 * 5 = 150.

2. Step 2: Compare P with P_prev and update V_ref

   Since 150 > 140, V_ref = V + 0.1 = 30 + 0.1 = 30.1.

3. Final Answer:

   30.1 -> Option C

4. Quick Check:

   150 > 140 so V_ref = 30 + 0.1 = 30.1 [OK]

Hint: Calculate power first, then compare to update voltage [OK]

Common Mistakes:

• Using old V instead of updated V_ref
• Mixing up greater than and less than conditions
• Forgetting to update P_prev

4. In a Simulink MPPT model, the output power does not increase as expected. Which of the following is a likely error in the MPPT algorithm block?

medium

A. The voltage reference is not updated based on power comparison

B. The solar panel block is missing

C. The Scope block is not connected

D. The battery capacity is too low

Solution

1. Step 1: Analyze MPPT algorithm role

   MPPT must update voltage reference to track max power point.

2. Step 2: Identify impact of no voltage update

   If voltage reference stays constant, power won't increase even if sunlight changes.

3. Final Answer:

   The voltage reference is not updated based on power comparison -> Option A

4. Quick Check:

   MPPT voltage update missing = no power increase [OK]

Hint: MPPT must update voltage ref to increase power [OK]

Common Mistakes:

• Blaming missing Scope for power issues
• Confusing battery capacity with MPPT function
• Ignoring voltage reference updates

5. You want to improve the MPPT algorithm in your Simulink solar panel model to handle rapidly changing sunlight conditions. Which approach is best to implement?

hard

A. Remove the MPPT block and rely on battery charging only

B. Use a perturb and observe method with adaptive step size

C. Fix the voltage reference to a constant value

D. Increase the solar panel size without changing MPPT

Solution

1. Step 1: Understand rapid sunlight changes impact

   Rapid changes require MPPT to quickly adjust voltage to track max power.

2. Step 2: Evaluate methods to improve MPPT

   Adaptive step size in perturb and observe method allows faster and stable tracking.

3. Step 3: Eliminate unsuitable options

   Fixing voltage or removing MPPT ignores changes; increasing panel size doesn't improve tracking.

4. Final Answer:

   Use a perturb and observe method with adaptive step size -> Option B

5. Quick Check:

   Adaptive MPPT handles rapid changes best [OK]

Hint: Adaptive step size in MPPT improves tracking speed [OK]

Common Mistakes:

• Keeping voltage fixed despite sunlight changes
• Removing MPPT thinking battery alone suffices
• Increasing panel size without MPPT tuning