External inlet air heating and internal exhaust gas recirculation (EGR) strategy cooperative control method

The invention discloses an external inlet air heating and internal exhaust gas recirculation (EGR) strategy cooperative control method. An engine which uses waste air to control inlet air temperature, uses a variable valve mechanism to control internal EGR and can measure the inlet air temperature is used. The external inlet air heating amount and the internal EGR rate are adjusted according to the inlet air temperature, and if the inlet air temperature is higher than the valve value, firstly, the internal EGR is reduced to 0, and the external inlet air heating amount is reduced; if the inlet air temperature is lower than the valve value, the internal EGR rate is increased while the external inlet air heating amount is increased; and if the if the inlet air temperature is equal to the valve value, the internal EGR rate is increased while the external inlet air heating amount is reduced. According to the external inlet air heating and internal EGR cooperative control method, by means of the internal EGR rate, the temperature in a cylinder can be improved rapidly under instantaneous work conditions, and the required temperature can be achieved. Under steady-state work conditions, external waste air heating and external heating EGR strategy inlet air heating are used for substituting for an internal EGR strategy, so that pump air losses can be reduced, and an optimum economy property is achieved.