Hello all,
I am trying to make a MPPT solar charger. I have read some articles about MPPT and seen several codes for this. Few things I don't understand, and hope someone knowledgeable may kindly help me.
* The solar panel is rated to 10 watts. Maximum output voltage is 22 volts.
* The battery would be charged, is a 12 volts lead acid battery.
* When the battery voltage reaches at 14.4 volts, it is fully charged.
Say for example, the maximum power point of the solar panel is 18 volts.
To make the battery fully charged (14.4v), I have to supply like 15.4 or 16 volts.
So when the solar panel volt is 18, I have to make it 16v with a buck converter or other dc/dc converter.
Even, when the solar panel voltage is 17, 19, 20, 21 or maximum 22v, I have to adjust pwm for a 16v output to charge the battery.
The articles and codes I read, measure voltage and current of the solar panel to determine power. This way they find the maximum power point of the panel. Here I don't understand why to do this.
May be I shall find that the maximum power point is on 19v instead of 18v. Or it will be 20v, 21v or 22v. Whatever it is, I have to adjust the solar voltage to 16v to charge the battery. Then why sense solar current to find maximum power point?
Shall the solar voltage have to be changed to 17 or any other volts if the MPP is 19v, instead of 18v?
As I understand it is sufficient to convert the voltage to 16v for charging the battery. Saved higher voltages will be converted to current which will help the battery to charge faster. The MPP might be hidden in any of the 18, 19, 20, 21 or 22v. It is not necessary to discover it to charge the battery. To find it the voltage and current are read through ADC, then multiplied to get the power/watt. Why to do this - measuring current? When I need 16v, I have only need to look for higher solar voltage to adjust pwm. I need ADC to determine only voltage.
Well, I understand that so many people who wrote the articles and codes for MPPT charger can't be wrong. So I am making mistake somewhere. Can someone please correct me and explain it?
Thanks a lot.
Best regards.
I am trying to make a MPPT solar charger. I have read some articles about MPPT and seen several codes for this. Few things I don't understand, and hope someone knowledgeable may kindly help me.
* The solar panel is rated to 10 watts. Maximum output voltage is 22 volts.
* The battery would be charged, is a 12 volts lead acid battery.
* When the battery voltage reaches at 14.4 volts, it is fully charged.
Say for example, the maximum power point of the solar panel is 18 volts.
To make the battery fully charged (14.4v), I have to supply like 15.4 or 16 volts.
So when the solar panel volt is 18, I have to make it 16v with a buck converter or other dc/dc converter.
Even, when the solar panel voltage is 17, 19, 20, 21 or maximum 22v, I have to adjust pwm for a 16v output to charge the battery.
The articles and codes I read, measure voltage and current of the solar panel to determine power. This way they find the maximum power point of the panel. Here I don't understand why to do this.
May be I shall find that the maximum power point is on 19v instead of 18v. Or it will be 20v, 21v or 22v. Whatever it is, I have to adjust the solar voltage to 16v to charge the battery. Then why sense solar current to find maximum power point?
Shall the solar voltage have to be changed to 17 or any other volts if the MPP is 19v, instead of 18v?
As I understand it is sufficient to convert the voltage to 16v for charging the battery. Saved higher voltages will be converted to current which will help the battery to charge faster. The MPP might be hidden in any of the 18, 19, 20, 21 or 22v. It is not necessary to discover it to charge the battery. To find it the voltage and current are read through ADC, then multiplied to get the power/watt. Why to do this - measuring current? When I need 16v, I have only need to look for higher solar voltage to adjust pwm. I need ADC to determine only voltage.
Well, I understand that so many people who wrote the articles and codes for MPPT charger can't be wrong. So I am making mistake somewhere. Can someone please correct me and explain it?
Thanks a lot.
Best regards.
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