I'm going to turn this into sort of an idea-bouncing thread on AC control. Any EE's out there want to help me out with this one... I want to use an Hbridge to produce a sine wave. I understand the idea of PWMing the values of a sin table, it is the bridge that is confusing me. Lets talk about a 1-phase motor for now. The H-bridge has 2 high and two low mosfets. Lets call them AH, AL, BH, BL to represent side A and B of the motor and High and Low connection.
To generate a sin, is this correct:
Turn on AH 100%, BH 0%
PWM BL from 0 through 100% duty and back to 0 (sinusoidally)
Turn on BH 100%, AH 0%
PWM AL from 0 through 100% duty and back to 0 (winusoidally)
To me, this looks like the way to produce a full sin wave across the load in the H with minimal switch loss (high side staying on). Is there any problem with the high side staying on through a 180* and switching for the next 180*?
How does synchronous rectification play into this? Or does it? Would sync.rect. make my H-bridge turn into 6 mosfets? Or 8?
Hit me
