A rectifier converting AC to DC is easy enough to understand: Diodes let electricity only flow one way. But how in the world does an inverter convert DC to AC?
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In real power delivery applications there are a couple different modulations. A modulation is just a strategy for wave shaping, given a particular equipment design.
This isn’t really eli5 at all, my apologies.
First, used in early tech and the most intuitive, is variable frequency drive. VFD uses switching to build a step waveform at 60 hz. It’s not usually just a flat square, most common designs use three states (plus, zero, minus) and feed it through a choke filter to make a sine wave. [here’s a visual explanation ](https://realpars.com/variable-frequency-drive/)
Second, probably the most widely used modulation, is space vector modulation. SVM isn’t programmed to generate voltage, it’s programmed to generate current. It watches the grid voltage and switches in response to it, in order to send current to the grid & create positive power flow. Don’t worry, it’s kind of a mind job. [a visual guide](https://www.switchcraft.org/learning/2017/3/15/space-vector-pwm-intro) – note this paper talks about synthesizing voltage, I maintain that output voltage comes from the grid and SVM is better described as a current source.
These are just the two most popular methods, there are more, that deserve more research. Wavelet modulation works a lot like an audio encoder, solves a lot of problems with VFD, and can do plenty of things SVM just can’t.
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