LApprenti Sorcier
New Member
Hello everyone! Haven't posted for a while but I'm happy to see all the activity and enthusiasm that this forum has always hosted.
I'm writing because I need some tips for a project.
I'm trying to design some sort of electromechanical switch that will allow me to commute between two different power supplies.
The device to be powered uses ~120VAC and considerable (but variable) power (several incandescent bulbs and an electronic controller).
I want to be able to switch between ~120VAC mains and ~120VAC fuel-powered generator ***without interrupting power to the device***.
The general considerations I've thought of (and what's mostly bothering my mind) are:
- I've thought I can use a group of capacitors to power the source while the sources are being switched, but I've only ever heard of this for DC, how does this work for AC? (Large capacitors are electrolytic and most importantly *have polarity*).
- If I do carge capacitors to supply energy during the commutation, a problem arises: Say, for example, that the mains is disconnected in the instant the wave is 120V+, the capacitor is charged to that voltage. I don't think it would be a great idea to reconnect the fuel-powered generator on the instant when it is 0V or -120V, causing a short circuit of somekind. And I definitely can't synchronise the sources, it's not an option.
- The device being powered has a regular power supply (transformer, rectifying diodes, capacitors, regulator), how would an irregular AC waveform affect it (when hopping from one wave to another un-synchronised one)?
- If it's not affected by the irregular waveform, then, maybe it's not affected by a sporadic disconnection of a few milliseconds? (meaning that I don't need to use those capacitors I mentioned above?)
Thanks for your feedback everyone!
I'm writing because I need some tips for a project.
I'm trying to design some sort of electromechanical switch that will allow me to commute between two different power supplies.
The device to be powered uses ~120VAC and considerable (but variable) power (several incandescent bulbs and an electronic controller).
I want to be able to switch between ~120VAC mains and ~120VAC fuel-powered generator ***without interrupting power to the device***.
The general considerations I've thought of (and what's mostly bothering my mind) are:
- I've thought I can use a group of capacitors to power the source while the sources are being switched, but I've only ever heard of this for DC, how does this work for AC? (Large capacitors are electrolytic and most importantly *have polarity*).
- If I do carge capacitors to supply energy during the commutation, a problem arises: Say, for example, that the mains is disconnected in the instant the wave is 120V+, the capacitor is charged to that voltage. I don't think it would be a great idea to reconnect the fuel-powered generator on the instant when it is 0V or -120V, causing a short circuit of somekind. And I definitely can't synchronise the sources, it's not an option.
- The device being powered has a regular power supply (transformer, rectifying diodes, capacitors, regulator), how would an irregular AC waveform affect it (when hopping from one wave to another un-synchronised one)?
- If it's not affected by the irregular waveform, then, maybe it's not affected by a sporadic disconnection of a few milliseconds? (meaning that I don't need to use those capacitors I mentioned above?)
Thanks for your feedback everyone!