Second throat control system and method for transient wind tunnel

The invention relates to a second throat control system and method for a transient wind tunnel. The system comprises an execution module and a control module. The execution module comprises a servo motor and a matched driver thereof, a pull rope sensor is used for gate finger position feedback, and a travel switch is used for gate finger safety interlocking; the control module adopts a distributed architecture and comprises an upper computer program and a lower computer program. The upper computer program is responsible for instruction issuing, state monitoring and test data storage; the lower computer program is responsible for Mach number control, data acquisition and safety linkage. The system is realized based on grid fingers, and the wind tunnel flow field Mach number control precision can be improved. According to the method, the Mach number control law is formed by combining feedforward control and variable parameter PID control, and Mach number control hysteresis and control overshoot can be effective