Vehicle control method and vehicle control system

A vehicle control method for automatically controlling travel of a host vehicle, the vehicle control method comprising:

• acquiring traffic jam information indicating whether or not a travel lane of the host vehicle is jammed;
• when it is determined based on the traffic jam information that the travel lane is not jammed, performing basic self-driving control including intervehicle maintaining control configured to maintain an intervehicle distance between the host vehicle and a preceding vehicle in a predetermined range;
• when it is determined based on the traffic jam information that the travel lane is jammed, performing in-traffic-jam self-driving control including low torque travel control configured to cause the host vehicle to travel by a low drive torque lower than a drive torque determined based on the basic self-driving control;
• and
• when the intervehicle distance exceeds a predetermined upper limit distance in the in-traffic-jam self-driving control, causing the host vehicle to travel by a drive torque higher than the low drive torque of in-traffic-jam self-driving control even while the travel lane is jammed.

A vehicle control system for automatically controlling travel of a host vehicle, the vehicle control system comprising:

• an intervehicle distance acquisition device configured to acquire an intervehicle distance between the host vehicle and a preceding vehicle;
• a traffic jam information acquisition device configured to acquire traffic jam information indicating whether or not a travel lane of the host vehicle is jammed;
• and
• a self-driving controller configured to control the travel of the host vehicle based on the intervehicle distance and the traffic jam information,
• wherein the self-driving controller is configured to:
• when it is determined based on the traffic jam information that the travel lane is not jammed, perform basic self-driving control including intervehicle maintaining control configured to maintain the intervehicle distance in a predetermined range;
• when it is determined based on the traffic jam information that the travel lane is jammed, perform in-traffic-jam self-driving control including low torque travel control configured to cause the host vehicle to travel by a low drive torque lower than a drive torque determined based on the basic self-driving control;
• and
• when the intervehicle distance exceeds a predetermined upper limit distance in the in-traffic-jam self-driving control, causing the host vehicle to travel by a drive torque higher than the low drive torque of in-traffic-jam self-driving control even while the travel lane is jammed.