EagleTalonTim
Newbie level 3
- Joined
- Dec 23, 2007
- Messages
- 3
- Helped
- 0
- Reputation
- 0
- Reaction score
- 0
- Trophy points
- 1,281
- Activity points
- 1,330
Hello all! I am getting into the solar hobby and have high hopes of building my own charge controller to handle up to 700W. I have been through this on another forum and most of the responses on there were to go buy a premade one or < 20A circuits, but I am a DIY'er and don't mind spending a little extra time learning as I go along. I just need help being started in the right direction with the right components.
To start with the project, I need to build a Buck Converter that can be driven by a processor that outputs 3.3V and can source / sink 40ma per pin. Since this is much higher voltage and higher amperage than I have ever worked with, I need help selecting the right components. My preferred place I like to order from is DigiKey and I have spent a bunch of time on there recently trying to determine what components I could use.... The more I look at it, the more scared I get!
After days of researching and doing some bench testing with lower amperage (< 10A), I have learned that the turn off time of a Mosfet is key. I dabbled with using an Op-Amp to drive a P-Channel mosfet but ran into problems with frequency and "ringing" on the gate. During my journey of researching, I have learned about IGBT's and they have sparked my interest, but I have never used one and would not know how to properly drive one at the frequency most recommend (20khz to 50khz). I don't mind running at a lower frequency if it gives me room for error (including heat sink sizing).
The Gate Driver IR2101 looks to be promising, but I am not very good at the math side of electronics and am unsure if it can drive an IGBT properly at the current I am looking to run and the frequency. The Ton and Toff seem to be a little slow if my math is correct. 50khz = 50ns?
Product Details : https://www.digikey.com/product-detail/en/IR2101STRPBF/IR2101SPBFCT-ND/827940
Also, this IGBT (APT30GP60BDQ1G) is probably way too much, but it can handle the switching frequency and current.
https://www.digikey.com/product-detail/en/APT30GP60BDQ1G/APT30GP60BDQ1G-ND/1434704
From what I understand, I will also need either a very fast diode for the flyback diode, or I can use an N-Channel mosfet? Does this component also need to be rated at the high amperage as the high side IGBT or Mosfet I select?
Am I looking at the right components or is there a better alternative? I do greatly appreciate any help I get on this!
To start with the project, I need to build a Buck Converter that can be driven by a processor that outputs 3.3V and can source / sink 40ma per pin. Since this is much higher voltage and higher amperage than I have ever worked with, I need help selecting the right components. My preferred place I like to order from is DigiKey and I have spent a bunch of time on there recently trying to determine what components I could use.... The more I look at it, the more scared I get!
After days of researching and doing some bench testing with lower amperage (< 10A), I have learned that the turn off time of a Mosfet is key. I dabbled with using an Op-Amp to drive a P-Channel mosfet but ran into problems with frequency and "ringing" on the gate. During my journey of researching, I have learned about IGBT's and they have sparked my interest, but I have never used one and would not know how to properly drive one at the frequency most recommend (20khz to 50khz). I don't mind running at a lower frequency if it gives me room for error (including heat sink sizing).
The Gate Driver IR2101 looks to be promising, but I am not very good at the math side of electronics and am unsure if it can drive an IGBT properly at the current I am looking to run and the frequency. The Ton and Toff seem to be a little slow if my math is correct. 50khz = 50ns?
Product Details : https://www.digikey.com/product-detail/en/IR2101STRPBF/IR2101SPBFCT-ND/827940
Also, this IGBT (APT30GP60BDQ1G) is probably way too much, but it can handle the switching frequency and current.
https://www.digikey.com/product-detail/en/APT30GP60BDQ1G/APT30GP60BDQ1G-ND/1434704
From what I understand, I will also need either a very fast diode for the flyback diode, or I can use an N-Channel mosfet? Does this component also need to be rated at the high amperage as the high side IGBT or Mosfet I select?
Am I looking at the right components or is there a better alternative? I do greatly appreciate any help I get on this!
