Driving force control system for hybrid vehicle

A driving force control system for a hybrid vehicle comprising:

• a prime mover including an engine and a motor;
• a particulate filter that captures particulate matter contained on an exhaust gas emitted from the engine;
• and
• an electric storage device that supplies electric power to the motor,
• wherein an operating mode of the hybrid vehicle is selected at least from
• a hybrid mode in which the hybrid vehicle is propelled by at least a part of a power generated by the engine and a power generated by the motor, and
• a motor mode in which the hybrid vehicle is propelled only by the power generated by the motor,
• the driving force control system further comprises a controller that controls the engine and the motor,
• the controller is configured to
• shift the operating mode from the motor mode to the hybrid mode based on a state of charge level of the electric storage device, and
• set a threshold level of the state of charge level to shift the operating mode from the motor mode to the hybrid mode to a higher level and set an upper limit power of the engine in the hybrid mode to a lower power in a situation where amount of the particulate matter accumulated in the particulate filter is equal to or smaller than a predetermined amount, compared to the threshold level and the upper limit power set in a situation where the amount of the particulate matter accumulated in the particulate filter is greater than the predetermined amount.