For most breeds of pigs three lines of wire with even spacings will provide an effective electric fence. Obviously, the smaller breeds should have the bottom wire closer to the ground and with piglets a couple of extra lines will be needed to ensure that they stay in close proximity to the sow.
We've created many pig encloseres over the years and found that the most basic setups make the best systems.
A wooden corner post with ring insulators in it and a few lines of either stranded steel or polytwine held in place by plastic posts makes an excellent pen for keeping your pigs in. When going through the rings at the corners wrap the wire round the insulator too to help keep the tension on the line.
For a gate we've found that having a specific gate in place can be of little use when getting on with the day to day jobs and most people just step over the wires. For taking a vehicle in or the pigs out our customers have found that by having the individual lines of the fence end in a loop on the same corner post they can just turn off the energiser and unclip them easily. To get the power from one vertical line to another, it's best to use a lead like this
or like this