Inverter

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2018-02-10

This project is to try to create an inverter as a learning exercise. Drawing on this (by Nick Zouein) as inspiration, I'm interested in producing a small inverter as a proof of concept for a possible future in an off-the-grid life. By practicing the basics, I hope to learn skills which will allow me to create larger systems in the future. It will also give me an excuse to refer to my university notes.

Monolith
An example of the inverter topology I will probably use (except the switching will be done with a microcontroller). Source: http://www.smps.us/mosfet_inverter.png

Having done some reading on the topic, I understand a few things:

  1. I could use a microcontroller to create the PWM switching needed for the driver, though I will have to make sure the code is bulletproof to prevent any issues with short circuits
  2. I will need to use a driver (or two) to allow the microcontroller's output to interface with the input of a MOSFET. A good choice of river might be the MIC4421/2. There are also some great resouces in here which are worth reading as part of the MOSFET selection/circuit design.
  3. I'll need some low impedance, fast switching (switching causes the MOSFET to move through a medium impedannce state which consumes lots of power), high voltage MOSFETs. A good choice might be the IRFP250.
  4. I'm going to need a center tapped transformer to take me from ~12 V to ~240 V. Although it's possible to buy one, it would be more economical (and fun!) to make one myself. One way to do this is to steal one out of a microwave, and modify it to suit.

This is a low priority project at the moment, but hopefully I can get to it soon.

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