Runaway prevention protection device and variable-pitch control system

The utility model discloses a runaway prevention protection device and a variable-pitch control system. The runaway prevention protection device comprises an acceleration switch which is arranged on a wind wheel hub. The acceleration switch is composed of an acceleration sensor, a signal conversion module and a speed detection control module which are sequentially connected, wherein the speed detection control module is connected with an emergency feathering command (EFC) input terminal of a motor driver in the variable-pitch control system. The runaway prevention protection device is provided based on an original variable-pitch control system. The set value of the rotation speed of a wind wheel is larger than that of an original system. When a speed limit device of the original system fails and cannot perform the emergency feathering function to obtain safe feathering, the rotation speed of the wind wheel increases continuously. When the rotation speed of the wind wheel reaches to the set value, a contact po