Hello all,
I'm new to the forum and honestly quite new to electronics in general. I'm working at the moment on a school project in which my teacher told us to design a buck converter using raspberry pi. The final goal should be to use a solar panel to power the circuit and use MPPT to charge a battery. For now I'm still trying to make the circuit work using a power supply. I'm working with a 100kHz signal from raspberry pi and 12V power supply. I'm trying to charge a 3.7V battery. You'll find attached the circuit schematic.
For now I've achieved the circuit working and it actually charges the battery, but not exactly the way it should.
The problems I'm facing at the moment are:
- The circuit is working and it charges the battery, however I've calculated the components based on the Vin/Vout, frequency and duty cycle, and I'm obtaining the inverse duty cycle that I'd be supposed to get. For example, I should be getting aroun d 36% duty cycle, and the result I'm obtaining on the raspberry pi is 64% (it matches somewhat the value on osciloscope too)
- The duty cycle that raspberry pi shows doesn't match the osciloscope by some percentage. There's 4-5% discrepancy at 100 kHz. If I increase the frequency, the duty cycle error between the Pi and the osciloscope gets bigger.
- The solar panels we will be testing deliver around 5V. I've tried lowering the power supply voltage to around 5V but then it isn't enough to trigger the mosfet driver. It needs around 10V to work properly. Is there anyway I can make it work with less voltage?
I'm sorry if I'm making stupid questions and basic errors. I should add my teacher doesn't really understand much on the subject (he's a substitute teacher) and all the answers he gives me are related to "do a google search". I also have few bases in electronics so I'd be glad if you can refer some literature you might think is appropriated. Also, sorry if the schematic isn't correct, it's my first time using EDA. I'm kinda learning everything at the same time because I'm on a tight deadline. I feel quite lost
I'm new to the forum and honestly quite new to electronics in general. I'm working at the moment on a school project in which my teacher told us to design a buck converter using raspberry pi. The final goal should be to use a solar panel to power the circuit and use MPPT to charge a battery. For now I'm still trying to make the circuit work using a power supply. I'm working with a 100kHz signal from raspberry pi and 12V power supply. I'm trying to charge a 3.7V battery. You'll find attached the circuit schematic.
For now I've achieved the circuit working and it actually charges the battery, but not exactly the way it should.
The problems I'm facing at the moment are:
- The circuit is working and it charges the battery, however I've calculated the components based on the Vin/Vout, frequency and duty cycle, and I'm obtaining the inverse duty cycle that I'd be supposed to get. For example, I should be getting aroun d 36% duty cycle, and the result I'm obtaining on the raspberry pi is 64% (it matches somewhat the value on osciloscope too)
- The duty cycle that raspberry pi shows doesn't match the osciloscope by some percentage. There's 4-5% discrepancy at 100 kHz. If I increase the frequency, the duty cycle error between the Pi and the osciloscope gets bigger.
- The solar panels we will be testing deliver around 5V. I've tried lowering the power supply voltage to around 5V but then it isn't enough to trigger the mosfet driver. It needs around 10V to work properly. Is there anyway I can make it work with less voltage?
I'm sorry if I'm making stupid questions and basic errors. I should add my teacher doesn't really understand much on the subject (he's a substitute teacher) and all the answers he gives me are related to "do a google search". I also have few bases in electronics so I'd be glad if you can refer some literature you might think is appropriated. Also, sorry if the schematic isn't correct, it's my first time using EDA. I'm kinda learning everything at the same time because I'm on a tight deadline. I feel quite lost
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