METHOD AND DEVICE FOR CONTROLLING A SOLENOID ACTUATOR

摘要

A solenoid actuator for an injection valve or an intake valve is driven with current control during closed-loop control phases. In between the closed-loop current control, the actuator must be clamped to an opposite voltage so as to quickly decrease the current through the solenoid. The current is measured immediately following the clamping phase so as to determine whether or not the clamping phase resulted in the correct current level. If the measured current indicates an extraneous reduction in the current, the clamping phase duration is shortened for the next activation of this clamping phase. If the measured current indicates an insufficient decrease, the clamping phase duration is lengthened for the next following activation cycle.

主权项

1. A method of driving a solenoid actuator, the method comprising:
connecting a voltage signal to the actuator and causing an electric current to flow through the actuator, the current having mutually different current intensities during temporally offset phases of actuator operation; selectively operating the actuator during a plurality of temporally subsequent closed-loop current control phases during which the current is maintained within a given target window defined between a lower current set point and a higher current set point, wherein the current through the actuator is measured and the voltage signal is adjusted to cause the current to remain within the given target window; selectively operating the actuator in a clamping phase between two respective closed-loop current control phases, during which clamping phase the current through the actuator is decreased by applying an inverted voltage signal to the actuator for a given clamping time period; measuring the current through the actuator immediately following the clamping phase to determine whether the current intensity has undershot or overshot the target window of the subsequent closed-loop current control phase; and generating a redefined clamping time period for a next following activation cycle by one of the following:
if the current intensity has undershot the lower current set point of the target window, decreasing the given clamping time period by a defined unit of time; orif the current intensity has overshot the upper current set point of the target window, increasing the given clamping time period by a defined unit of time; orif the current intensity measured immediately following the clamping phase lies within the target window, retaining the given clamping time as the redefined clamping time period; and operating the actuator in the next following activation cycle with the redefined clamping time period.