Control system and method for multi-stage safety handle of excavator

The invention discloses a control system and method for a multi-stage safety handle of an excavator. The control system comprises a first-stage contact switch, a second-stage contact switch, the safety handle, a pilot oil source, a left pilot handle, a right pilot handle, a first-stage safety electromagnetic valve, a second-stage safety electromagnetic valve, a rotary safety valve and a walking pedal valve. The first-stage contact switch and the second-stage contact switch are independently arranged in the safety handle. The first-stage safety electromagnetic valve is connected with the first-stage contact switch, the pilot oil source, the left pilot handle and the right pilot handle respectively. The second-stage safety electromagnetic valve is connected with the second-stage contact switch, the pilot oil source, the walking pedal valve and the rotary safety valve respectively. The rotary safety valve is further connected with the left pilot handle and controls connection and disconnection between rotary pil