SPINDLE THERMAL ERROR COMPENSATION METHOD INSENSITIVE TO DISTURBANCE OF COOLING SYSTEM

摘要

A spindle thermal error compensation method insensitive to disturbance of a cooling system. The method comprises: firstly, performing a spindle model coefficient identification test based on a multi-state variable rotational speed; secondly, determining a temperature measuring point having a significant correlation degree with an axial thermal error of a spindle on the basis of a correlation analysis of the temperature and thermal error; thirdly, building a spindle thermal error model which is insensitive to the disturbance of the cooling system, and performing identification under a constraint condition on coefficients in the model on the basis of a non-linear quadratic programming algorithm; and finally, writing a compensation value calculated by the model into a numerical-controlled system on the basis of an OPC UA communication protocol to implement compensation of the thermal error of the spindle. The method has the advantages of high model prediction accuracy and high robustness, and can still keep a good compensation effect especially in the case of frequent start-up of the cooling system and other disturbances.