Frequency and Force Amplitude Control of Hydraulic Vibro-hammering Machine

Abstract

The vibro-hammering machine generates vibrating force to drive a pile, driving four eccentric rotors by hydraulic motors. In this research, a control method of the force amplitude of a vibro-hammering machine under variable frequency drive is developed, which controls both the rotating speed and relative angles of four eccentric rotors. The pump displacement control and the by-pass valve control are applied to the frequeucy control loop and the force amplitude control loop respectively. The performances of the system are discussed by experiment.