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Mistake in calculation of rmsRMS current flyback primary switch node

I'm trying to calculate the rmsRMS current of a flyback converters primary switch node. The Waveform is shown below:

enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula iI found on the internet:

Text

And iI will find a RMS current of 0.51A what is right.

But my problem is when iI try to calculate it with another method i believe is right iI get a different anwseranswer. I hope someone can point out me where i'mI'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$ I

I end up wrong. I think my problem is with the simplifactionsimplification. But it doesn't make sense to me why it should be wrong.

Thanks in advance. I hope my post is also inline with the forum guidlines. As this is my first post. So tips are also welcome

Mistake in calculation of rms current flyback primary switch node

I'm trying to calculate the rms current of a flyback converters primary switch node. The Waveform is shown below:

enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula i found on the internet:

Text

And i will find a RMS current of 0.51A what is right.

But my problem is when i try to calculate it with another method i believe is right i get a different anwser. I hope someone can point out me where i'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$ I end up wrong. I think my problem is with the simplifaction. But it doesn't make sense to me why it should be wrong.

Thanks in advance. I hope my post is also inline with the forum guidlines. As this is my first post. So tips are also welcome

Mistake in calculation of RMS current flyback primary switch node

I'm trying to calculate the RMS current of a flyback converters primary switch node. The Waveform is shown below:

enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula I found on the internet:

Text

And I will find a RMS current of 0.51A what is right.

But my problem is when I try to calculate it with another method i believe is right I get a different answer. I hope someone can point out me where I'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$

I end up wrong. I think my problem is with the simplification. But it doesn't make sense to me why it should be wrong.

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I'm trying to calculate the rms current of a flyback converters primary switch node. The Waveform is shown below:   

enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula i found on the internet:

Text

And i will find a RMS current of 0.51A what is right.

But my problem is when i try to calculate it with another method i believe is right i get a different anwser. I hope someone can point out me where i'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$ I end up wrong. I think my problem is with the simplifaction. But it doesn't make sense to me why it should be wrong.

Thanks in advance. I hope my post is also inline with the forum guidlines. As this is my first post. So tips are also welcome

I'm trying to calculate the rms current of a flyback converters primary switch node. The Waveform is shown below:  enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula i found on the internet:

Text

And i will find a RMS current of 0.51A what is right.

But my problem is when i try to calculate it with another method i believe is right i get a different anwser. I hope someone can point out me where i'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$ I end up wrong. I think my problem is with the simplifaction. But it doesn't make sense to me why it should be wrong.

Thanks in advance. I hope my post is also inline with the forum guidlines. As this is my first post. So tips are also welcome

I'm trying to calculate the rms current of a flyback converters primary switch node. The Waveform is shown below: 

enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula i found on the internet:

Text

And i will find a RMS current of 0.51A what is right.

But my problem is when i try to calculate it with another method i believe is right i get a different anwser. I hope someone can point out me where i'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$ I end up wrong. I think my problem is with the simplifaction. But it doesn't make sense to me why it should be wrong.

Thanks in advance. I hope my post is also inline with the forum guidlines. As this is my first post. So tips are also welcome

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Mistake in calculation of rms current flyback primary switch node

I'm trying to calculate the rms current of a flyback converters primary switch node. The Waveform is shown below: enter image description here

I'm okay with assuming it is a triangle wave with a duty cycle of 50%. The peak value is 1.25A and the Period time is 4u seconds.

I can calculate it using the following formula i found on the internet:

Text

And i will find a RMS current of 0.51A what is right.

But my problem is when i try to calculate it with another method i believe is right i get a different anwser. I hope someone can point out me where i'm wrong. See my calculation below:

$$ I_{RMS} = \sqrt{\frac{1}{T}\cdot\int_{0}^{T}I^2(t)dt} $$

I then simplify the integral to an easy area calculation

$$\int_{0}^{T}I^2(t)dt = (0.5 \cdot 0.5T \cdot I_{PK})^2$$

I work this all out to the following:

$$I_{RMS} = \sqrt{\frac{1}{T}(0.5 \cdot 0.5T \cdot I_{PK})^2}$$

When i fill everything in:

$$I_{RMS} = \sqrt{\frac{1}{4\mu}(0.5 \cdot 0.5 \cdot 2\mu \cdot 1.25)^2} $$ $$I_{RMS} = 3.125\cdot10^{-4} A $$ I end up wrong. I think my problem is with the simplifaction. But it doesn't make sense to me why it should be wrong.

Thanks in advance. I hope my post is also inline with the forum guidlines. As this is my first post. So tips are also welcome