Dynamic pressure precise control system when low vacuum system is continuously filled with working gas

The invention discloses a dynamic pressure precise control system when a low vacuum system is continuously filled with working gas. The dynamic pressure precise control system when the low vacuum system is continuously filled with the working gas comprises a vacuum chamber, a vacuum pump group, a vacuum pumping pipeline valve assembly, a working gas input unit, a regulating gas input unit, a pressure measuring unit and an electrical control unit. The vacuum pump group draws vacuum to the vacuum chamber through the vacuum pumping pipeline. The working gas input unit comprises a solenoid valve I, a mass flow controller I and a working gas pipeline to fill the vacuum chamber with the working gas. The regulating gas input unit comprises a solenoid valve II, a mass flow controller II and a regulating gas pipeline to fill the vacuum pump group with air. The electrical control unit uses a PLC to control the opening/closing of the vacuum pump group and the solenoid valves, set a working gas charging flow, set a targe