EGR PUMP SYSTEM AND CONTROL METHOD OF EGR PUMP

A method of operating exhaust gas recirculation pump for an internal combustion engine including: providing an EGR pump assembly including an electric motor coupled to a roots device having rotors, the EGR pump operably connected to an internal combustion engine; providing an system controller; providing an EGR control unit linked to the EGR pump assembly; sending a speed command from the system controller to the EGR control unit; determining if a motor temperature and module temperature is within a predetermined target; outputting a desired speed signal; determining if a motor speed is within a predetermined target; determining if a motor voltage is within a predetermined target; and outputting a current to the electric motor controlling the speed of the electric motor and regulating an EGR mass flow rate.