Control circuit for an electrochemical gas sensor and method for adjusting an electrochemical gas sensor
AssigneeContinental Automotive GmbH
InventorEkkehart-Peter Wagner
Life of this patent
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Abstract
An electrochemical gas sensor is provided for a motor vehicle. The gas sensor contains a digital controller and a detection circuit. The digital controller captures, by a feedback input, a value of the voltage applied to the inside of the gas sensor cell. The output of the digital controller provides a control value for the current flowing in the gas sensor cell. The detection circuit is used to detect the properties of the gas sensor cell and to adjust the dynamic control properties of the digital controller corresponding to the properties of the gas sensor cell.
Claims11
A control circuit for an electrochemical gas sensor for a motor vehicle, the control circuit comprising:
- a digital controller having a feedback input and an output, said digital controller receiving a value for a voltage present across a gas sensor cell by way of said feedback input, said output supplying a control value for a current flowing into the gas sensor cell;
- and
- a detection circuit for detecting properties of the gas sensor cell and for adjusting dynamic control properties of said digital controller according to the properties of the gas sensor cell;
- wherein said detection circuit detects the properties of the gas sensor cell based on the voltage dropping across the gas sensor cell when a step is applied to the current flowing into the gas sensor cell.
An assembly, comprising:
- a gas sensor cell for analyzing an exhaust gas;
- and
- a control circuit for said gas sensor cell, said control circuit containing:
- a digital controller having a feedback input and an output, said digital controller receiving a value for a voltage present across said gas sensor cell by way of said feedback input, said output supplying a control value for a current flowing into said gas sensor cell;
- and
- a detection circuit for detecting properties of said gas sensor cell and for adjusting dynamic control properties of said digital controller according to the properties of said gas sensor cell;
- wherein said detection circuit detects the properties of the gas sensor cell based on the voltage dropping across the gas sensor cell when a step is applied to the current flowing into the gas sensor cell.
A control method, which comprises the steps of:
- providing a control circuit for an electrochemical gas sensor for a motor vehicle, the control circuit containing a digital controller having a feedback input and an output, the digital controller receiving a value for a voltage present across a gas sensor cell by way of the feedback input and the output supplying a control value for a current flowing into the gas sensor cell, the control circuit further having a detection circuit for detecting properties of the gas sensor cell based on the voltage present across the gas sensor cell when a step is applied to the current flowing into the gas sensor cell and for adjusting dynamic control properties of the digital controller according to the properties of the gas sensor cell;
- and
- controlling, via the control circuit, an air/fuel mixture for an engine of the motor vehicle.
A method for adjusting an electrochemical gas sensor, which comprises the steps of:
- supplying a gas sensor cell for a motor vehicle;
- supplying a control circuit for the gas sensor, the control circuit containing a digital controller having a feedback input and an output, the digital controller receiving a value for a voltage present across the gas sensor cell by way of the feedback input and the output supplying a control value for a current flowing into the gas sensor cell, the control circuit further having a detection circuit for detecting properties of the gas sensor cell based on the voltage present across the gas sensor cell when a step is applied to the current flowing into the gas sensor cell and for adjusting dynamic control properties of the digital controller according to the properties of the gas sensor cell;
- and
- controlling the output of the digital controller so that the current flowing into the gas sensor cell has a current step;
- detecting the properties of the gas sensor cell based on the voltage present across the gas sensor cell when the step is applied to the current flowing into the gas sensor cell;
- and
- adjusting the dynamic control properties of the digital controller.
Dependencies are inferred from the claim text.