PROTECTION SYSTEM FOR WHR SYSTEM AND ENGINE SYSTEM

摘要

A first exhaust gas recirculation (EGR) valve is positioned within a first EGR passage fluidly connecting an engine exhaust stream and an engine intake stream, while a waste heat recovery (WHR) system is used to recover heat from the EGR stream. When the working fluid of the WHR system approaches a critical breakdown temperature, an engine control unit (ECU) closes the first EGR valve in response to a sensor reading and opens a second EGR valve positioned with a second EGR passage fluidly connecting the engine exhaust stream and the engine intake stream. The second EGR flow is cooled by an engine coolant loop before being routed into the engine intake system. The ECU also operates to divert the cooling working fluid flow away from a turbine when sensors indicate characteristics of the working fluid may be damaging to the turbine.