The pressure control system based on fixed-displacement oil pump is simple in structure

The utility model provides a pressure control system based on a fixed-displacement oil pump. The pressure control system based on the fixed-displacement oil pump is simplified in structure and comprises the fixed-displacement oil pump, a pressure limiting valve, a switch electromagnetic valve and a main oil duct. The fixed-displacement oil pump comprises an oil inlet cavity and an oil outlet cavity. The pressure limiting valve comprises a first pressure feedback cavity, a plunger, a transfer chamber, an oil inlet cavity connector, an oil outlet cavity connector, an oil outlet, a second pressure feedback cavity, a valve sleeve and a return spring. The oil outlet cavity connector is always communicated with the oil outlet through the transfer chamber; the main oil duct is connected to a first pressure feedback cavity and a second pressure feedback cavity of the pressure limiting valve through two independent oil ways respectively, a switch electromagnetic valve is arranged on the oil waybetween the first pressu