Method and apparatus for diagnosing abnormal state of valve
AssigneeVolvo Construction Equipment AB
InventorEun Byeol Lee
Life of this patent
Estimating the term…
Abstract
According to an embodiment of the present invention, there is provided a method of diagnosing an abnormal state of a valve including: applying a current having a predetermined intensity to a valve; estimating a resistance value of the valve on the basis of an intensity of a feedback current from the valve according to the application of the current and a voltage between both terminals of the valve; and when a difference between a resistance value of the valve estimated at a first time point and a resistance value of the valve estimated at a second time point is greater than or equal to a threshold, determining that abnormality has occurred in the valve.
Claims4
A method of diagnosing an abnormal state of a valve, comprising:
- obtaining a state of a target equipment comprising a valve, varied by an electrical signal;
- applying, by a valve controller, a current having a predetermined intensity to the valve, corresponded to the state of the target equipment, wherein the valve has two terminals;
- estimating a resistance value of the valve at a first point in time and a second point in time on the basis of an intensity of a feedback current from the valve according to the application of the current and a voltage between both terminals of the valve;
- and
- when a difference between a resistance value of the valve estimated at the first time point and a resistance value of the valve estimated at the second time point is greater than or equal to a threshold, determining that abnormality has occurred in the valve,
- wherein an interval between the first time point and the second time point is preset values,
- wherein the valve controller applies the current by controlling the voltage between the terminals of the valve through pulse width modulation (PWM) control,
- wherein, if the state of the target equipment is an off state, the applying of the current includes applying a first current and a second current having different intensities at the first time point and the second time point, respectively, and wherein the first point in time is at the time of standby state and the second point in time is at the time of the off state.
An apparatus for diagnosing an abnormal state of a valve, comprising a valve controller configured to:
- obtain a state of a target equipment comprising a valve, varied by an electrical signal;
- estimate a resistance value of a valve having two terminals by applying, at different points in time, a current having a predetermined intensity to the valve, corresponded to the state of the target equipment, and
- determine that abnormality has occurred in the valve when a difference between resistance values of valve estimated at different points in time is greater than or equal to a threshold,
- wherein an interval between the different points in time is preset values,
- wherein the valve controller applies the current by controlling a voltage between the terminals of the valve through pulse width modulation (PWM) control,
- wherein, if the state of the target equipment is an off state, the applying of the current includes applying a first current and a second current having different intensities at the first time point and the second time point, respectively, and wherein the first point in time is at the time of standby state and the second point in time is at the time of the off state.
Dependencies are inferred from the claim text.