High-pressure cold end EGR system of engine

The invention discloses a high-pressure cold end EGR system of an engine. The high-pressure cold end EGR system of the engine comprises an EGR cooler, an EGR valve, an EGR mixer and a controller. An exhaust gas channel and a cooling liquid channel are arranged in the EGR cooler, the gas intake end of the exhaust gas channel is connected with an exhaust pipe in front of a turbine of a supercharger,and after the exhaust gas is guided out from the exhaust pipe in front of the turbine of the supercharger, cooling of the exhaust gas is conducted in a heat exchange manner. The gas intake end of theEGR valve is connected with the gas discharge end of the exhaust gas channel of the EGR cooler. An exhaust gas inlet of the EGR mixer is connected with the gas discharge end of the EGR valve, and anair inlet of the EGR mixer is connected with an intake system of the engine. The high-pressure cold end EGR system of the engine is provided with relatively less connection pipelines, no pollution toan intercooler and the supercharger is generated, the change of the exhaust back pressure does not directly influence the EGR exhaust gas flow, and the transient state response is good. The heat resistance requirement for the EGR valve is low, and cost is low. The EGR valve is relatively easy to arrange.