Pressure control system of diaphragm compressor and control method of pressure control system

The invention discloses a pressure control system of a diaphragm compressor and a control method of the pressure control system. The pressure control system comprises a PID control device, a proportioning valve, a pressure transmitter, a diaphragm compressor and a hydrogen dispenser, wherein the proportioning valve is operably and electrically connected to the PID control device to receive the opening demand of the PID control device; the pressure transmitter is operably and electrically connected to the PID control device to acquire pressure data and then transmit the pressure data to the PIDcontrol device, so that the PID control device converts the pressure data into the opening command of the proportioning valve; the proportioning valve is arranged in a pipeline structure between an inlet and an outlet of the diaphragm compressor, and the pressure transmitter is arranged on an outlet pipeline of the diaphragm compressor; pipelines between the diaphragm compressor and the hydrogendispenser are connected th