Common type of servovalves is to control flowrate measuring and diagnosis of servovalve`s hysteresis is based upon analysis of flowrate signal. The ISO 10770-1 and KS B 6511 regulations for servovalve`s hysteresis are also established from analysis of...
Common type of servovalves is to control flowrate measuring and diagnosis of servovalve`s hysteresis is based upon analysis of flowrate signal. The ISO 10770-1 and KS B 6511 regulations for servovalve`s hysteresis are also established from analysis of flowrate signal. The measurement of flow is hard to implement. In this study, some hysteresis diagnosis methods are investigated to use pressure signal and spool displacement signal. Three kinds of hysteresis; flowrate hysteresis, pressure hysteresis and spool displacement hysteresis are measured from an experiment set-up. Two kinds of pressure hysteresis; pressure gain hysteresis and no-load pressure hysteresis are investigated. The spool displacement hysteresis is found to be the most accurate and pressure hysteresis are also good enough as well as flow hysteresis. The pressure gain hysteresis shows a little error from other hysteresis, and it is estimated because geometric dimension error of spool and sleeve affects the hysteresis.