Pneumatic pressure control system and method

The invention discloses a pneumatic pressure control system and method. The system is characterized by comprising a pressure sensor, a PLC control module with a preset target deviation calculation module, a PID control module, a PWM control module with a preset switching valve control rule, and a switching valve group module, wherein the switching valve group module comprises a valve group base, amain air inlet pipe and a main air outlet pipe, the main air inlet pipe and the main air outlet pipe are arranged in the valve group base, the main air inlet pipe is provided with a main air inlet communicated with an air supply port of external air supply equipment and an exhaust port provided with an exhaust switch valve, the main air outlet pipe is provided with a main air outlet communicatedwith an air inlet port of air consumption equipment, the main air inlet pipe is communicated with the main air outlet pipe through at least seven air inlet branch pipes which are not communicated withone another, and each air