The invention relates to a short-time forecasting method for a
traffic flow based on a macroscopic road
network model, which comprises the following steps: (1) obtaining the input flow of the source node of a road network at a forecasting period, extracting the average speed of each road section at a previous forecasting period and determining the
flow ratio of different turning directions at each intersection; (2) calculating the time of vehicles running to the
tail of a queued vehicle
queue, which are input on a road so as to obtain the number of the vehicles arriving at the
tail of the
queue at an iterative period; (3) determining the number of the vehicles which are correspondingly turned to leave the intersections by the conditions of the number of the vehicles queued at the intersections, the saturated leaving flow and the like; (4) accumulating to obtain the total number of the vehicles leaving the intersections at one forecasting period and converting to obtain the
traffic flow within the forecasting period; and (5) updating the number of the queued vehicles as known data for iterative forecasting at the next time. The short-time forecasting method for the
traffic flow based on the macroscopic road
network model aims at the defects that the adaptability of the road network is poor, a great deal of training data are needed, the operation quantity in a microscopic model is large and the like, which exist in the prior art. The spatial information of an
urban road network is fully utilized. The short-time forecasting method for the traffic flow based on the macroscopic road
network model is based on a
macroscopic traffic flow model, and the forecasting of the traffic flow of a road with high accuracy and good real-time property can be realized. Moreover, the short-time forecasting method for the traffic flow based on the macroscopic road network model is suitable for most of
urban road networks.