Abstract: In this paper, the principle of time-delay feedback control is applied to suppress or weaken the bifurcation of the traffic system so as to suppress traffic congestion. The key to this method is to find a stable time delay and feedback gain interval, that is to say, how to choose an appropriate parameter combination of time-delay and feedback gain to stabilize the solid angle model (SAM). Considering the effect of time-delay, the time-delay differential equation (DDE) is used to describe the traffic model with delay feedback control. However, it is difficult to make a dynamic analysis of DDE because of the infinite dimensional phase space. Existing studies of car-following models involving time-delay often ignore the time-delay term directly or use the small-delay approximation. Although the small delay approximation is simple and can easily be used to truncate the delay term, the results obtained are only valid for very small delays. To overcome this limitation and obtain an accurate stable interval, the definite integral stabilization method and the stable switching criterion are used to determine the stable interval of the reaction delay and feedback gain. Then a control strategy is designed to suppress the traffic congestion and stabilize the unstable traffic flow in the SAM. Numerical simulations are carried out to verify the practicability of the system. Numerical results demonstrate that reasonable feedback gain and delay settings can indeed effectively improve the stability of traffic flow.