Patent ID: 6234122
Filing Date: 2001-05-22
Classification: F01L

Abstract:
Method for driving an electromagnetic actuator for operating a gas change valve (5) in which the actuator with at least one electromagnet (2, 3) acts via an armature (1) on the gas change valve (5) against the force of at least one valve spring (60, 63) and operates said gas change valve (5) by movement of the armature (1), wherein a controlled variable (v.sub.IST) that depends on a change in inductance of the electromagnet (2, 3) is created as a measure of the impact velocity of the armature (1) on the electromagnet (2, 3), wherein the controlled variable is adjusted to a setpoint value (v.sub.SOLL) which corresponds to a predetermined value of the impact velocity of the armature (1) on the electromagnet (2, 3), by controlling the supply of energy to the electromagnet (2, 3), wherein the energy supply to the electromagnet (2, 3) is controlled by comparing the controlled variable (v.sub.IST) to the setpoint value (v.sub.SOLL) and by presetting a next closing time point (Tn.sub.n+1)I) of the electromagnet (2, 3) in accordance with the result of the comparison, wherein the closing time points (T.sub.n, T.sub.n+1) of the electromagnet (2, 3) are preset in accordance with system parameters, wherein control data is created from the closing time points (T.sub.n) of the electromagnet (2, 3) that become set for various system parameters, said control data being stored in a memory in accordance with the system parameters, and wherein when the system parameters change, the next closing time point (T.sub.n+1) of the electromagnet (2, 3) is obtained by feedforward control in accordance with the stored control data corresponding to the momentary system parameters.