The invention relates to a congestion control method and
system for multistage dynamic
speed limit of an expressway. The congestion
control system comprises a
traffic flow detection device, a variable
speed limit signboard and a
control unit. A highway in a management and
control area is divided into a plurality of sections by a plurality of sections, the
traffic flow detection devices and the variable
speed limit signboards are installed at the sections, the
traffic flow detection devices are used for collecting
vehicle driving data of each section within a preset time period, and the
control unit judges the state of each section according to the
vehicle driving data, determines a non-unblocked road section, and determines speed limit values of front n sections of the non-unblocked road section according to section
traffic volume of the front N sections of the non-unblocked road section. The speed limit values of the front n sections of all the non-unblocked road sections are integrated, the speed limit of a variable speed limit signboard is updated, and dynamic speed limit management of multi-stage sections is performed by utilizing the variable speed limit signboard. The driving speed of the vehicles in the management and
control area is controlled, the flow of the vehicles driving into the congested road section is reduced, and the
traffic congestion condition of the expressway is relieved.