What does Tianyuan match mean?

It refers to a car lottery system in Chinese mainland, which is one of the restrictive measures implemented according to urban traffic congestion.

In some large and medium-sized cities, due to the increasing traffic pressure and serious environmental pollution caused by too many motor vehicles, the government has adopted the method of "lottery" to limit the number of new motor vehicles. Tianyuan configuration uses random lottery to determine the amount needed to purchase new energy vehicles or ordinary fuel vehicles.