How does the electrical system in a light aircraft such as a Zenith CH-750 or Cessna 150 work compared with electrical systems in larger aircraft? Are the system is different than the electrical system on a common car? Do we need static electric discharge system?
Typically light normal category aircraft make use of either a 14 VDC or 28 VDC electrical systems powered primarily by an engine driven alternator. This provides power to one or more power bus bars which provide electrical power to the various aircraft systems requiring it. Below is an example light aircraft electrical system from a Cessna 172S.
One notable deviation from automobile electrical systems is that the engine spark plugs receive electricity from a separate pair of magnetos which produce their power independent of the main electrical system for reasons of redundancy.
Most light aircraft use 12vdc systems with belt driven alternators, like cars. They generally use the same alternators and voltage regulators, sometimes identical to the auto version but just having a more stringent quality control process.
Some heavier light planes use 24vdc systems, which allows for smaller, lighter wiring, and a bit less sensitive to bad connections with the higher voltage. More expensive to fix because the generators are dedicated aircraft units with no automotive equivalent.
For a homebuilt, you would just build a 12vdc system using automotive components, except for the battery, which has be be able to run upside down so it needs to be an aircraft one, although you could use an automotive gel cell battery.