Vehicular automatic power control system and method and car

The invention provides a vehicular automatic power control system and method and a car and belongs to the technical field of car control. The vehicular automatic power control system comprises a first sensor, a control unit and a power control feedback unit, wherein the first sensor is used for sensing the relative speed and/or relative distance between the car with the first sensor and a car behind the car with the first sensor; the control unit is used for transmitting a first control signal when the sensed relative speed and/or relative distance is larger than a preset value; the power control feedback unit is used for transmitting a reminding signal to the car behind so as to remind the driver of the car behind to start the car and follow the car with the first sensor. By the arrangement, the vehicular automatic powder control system can effectively relieve the problem that the distance between two cars is too large and traffic flow passing efficiency is influenced.