I was just thumbing through the web server log analyzer report and noticed a Google search come through that bears a comment. The query was regarding 2 AC power feeds to 1 DC power plant.
In my previous posts on DC power plant design, I have strongly recommended modular type rectifiers as the hardware of choice, equipped in an N+1 (or more) configuration to handle failure of a single module. In this scenario, I didn’t address AC redundancy, since the battery string would automatically take the load on failure of the AC power and have a reasonable run time that would allow restoration of AC power or switching to generator.
AC redundancy is certainly another layer of protection and is easily implemented with this type of power plant. Normally, rectifier modules in this type of plant are all individually powered. Simply power enough rectifiers to handle the load (plus 1) from one AC source and enough rectifiers to handle the load (plus 1) from the other AC source.
What are the disadvantages of this? You’re limited to using less than half the capacity of your power plant. Since either half could end up carrying the whole load by itself, you now need a spare module (the plus 1) for each half.
I believe that in most if not all cases, this is going to be serious overkill and a tremendous waste of money to operate this way.
Vern, SwiftWater Telecom