The three-phase, four-wire system does not have a ground wire. The so-called three-phase four-wire means three-phase wires and a working neutral wire. The term ground wire is not accurate. It is now called the protected neutral line, also called the PE line. Essentially, working on the neutral line is equivalent to protecting the neutral line. They are all connected to the earth. However, the grounding resistance of the two is different and, as mentioned above, the working neutral line participates in the work being done (380 to 220 V). So it works, but it can cause an electric shock.
If your generator is some distance from the transformer and the long-term resistance of the working earth is large, there will be voltage on the unbalanced neutral line of the three-phase load when the generator is lit. At this time, if anyone works on the power line, there is a risk of electric shock.
Ifyou need to sign a safety agreement with the power supply service for your own power supply, you can repeatedly ground it to the main neutral line (but it depends on the nature of your power line and a le leak protector cannot be installed on the front)