| 摘要 |
<p num="1">A system for optimising the power to a core of a valve in a position of the valve comprises at least one valve and a controller unit. The at least one valve comprises a core operable between a first position and a second position, and the controller unit defines an inrush DC voltage level signal for forcing the core into the second position, and further defines a hold DC voltage level signal for retaining the core in the second position. The controller unit, in the first position of the core, provides a valve control signal with the hold DC voltage level and measures a first self inductance representing the core in the first position. The controller unit, in the first position of the core, provides the valve control signal with the inrush DC voltage level signal for forcing the core from the first position to the second position, and subsequently the controller unit provides the valve control signal with the hold DC voltage level for retaining the core in the second position, and the controller unit measures, in the second position of the core, a second self inductance representing the core in the second position. The controller unit, in the second position of the core, while providing the valve control signal with the hold DC voltage level gradually decreases the hold DC voltage level and measures a third self inductance representing the actual physical position of the core. The controller unit determines on basis of the first or second self inductance in comparison with the third self inductance whether the core is in the first or second position.</p> |
