G01N27/4065

Control device for gas sensor

An SCU as a control device for the gas sensor (first and second NOx sensors) includes an applied voltage switching unit for switching an applied voltage of a pump cell when a deterioration detecting function is performed, and a deterioration rate calculation unit for calculating a deterioration rate of a sensor cell based on a slope during a transient change in an output of the sensor cell according to a switching of the applied voltage by the applied voltage switching unit.

SENSOR CONTROL DEVICE

To provide a sensor control device capable of identifying a short circuit terminal with a simple configuration and whose identification operation is not easily affected by environmental conditions around the sensor. The sensor control device includes a short circuit detection unit that detects a short circuit of a sensor having a plurality of terminals, a resistance value control unit that increases a resistance value of an element between the terminals when the short circuit of the sensor is detected by the short circuit detection unit, and a short circuit terminal identification unit that identifies at which of the plurality of terminals a short circuit occurs when the resistance value control unit increases the resistance value of the element between the terminals to a set value or greater.

METHOD FOR DIAGNOSING EXHAUST GAS SENSORS

An evaluation and control unit for operating a wideband lambda sensor that has at least two electrical lines, the evaluation and control unit having at least two electrical terminals for electrical connection to the electrical lines of the wideband lambda sensor. Each of the electrical terminals has assigned to it a respective electrical switch via which each terminal is capable of being individually connected to at least one defined electrical potential. Each switch is voltage-resistant against the maximum short-circuit voltage that is to be expected at the respective terminal in case of fault. In addition, a method is described for the line-specific short-circuit diagnosis of the wideband lambda sensor (pinpointing).

Oxygen sensor system and method

An oxygen sensor is in a system including compensator circuitry connected to the oxygen sensor. The oxygen sensor includes a pump cell and the compensator circuitry includes a feedback control loop which includes a digital compensator which determines and outputs a compensation current to the pump cell or adjusts a pump cell voltage. A method of controlling the oxygen sensor includes, subsequent to a period of time when the feedback control loop is disrupted, pumping a balancing current into or out the pump cell for a balancing time interval, the balancing current and/or the balancing time interval is dependent on a current pumped into or out of the pump cell prior to the feedback control loop being disrupted.

NOx SENSOR AND NOx SENSOR OPERATION METHOD
20230273148 · 2023-08-31 ·

A controller of a NOx sensor determines whether a determination target value being an indicator of operation of pumping in oxygen of one of electrochemical pump cells other than a measurement pump cell including inner electrodes arranged in respective internal spaces of a sensor element, an out-of-space pump outer electrode disposed at a location other than the internal spaces, and solid electrolytes between these electrodes exceeds a threshold during a predetermined determination time, controls, unless the determination target value exceeds the threshold, the NOx sensor in a basic mode in which a concentration of NOx is identified based on a pump current flowing between the measurement electrode and the outer electrode, and stops, when the determination target value exceeds the threshold, the basic mode, and controls the NOx sensor in a protected execution mode in which the measurement electrode is protected against over-reduction.

Gas sensor control device

A control device performs deterioration diagnosis of a gas sensor including a pump cell and a sensor cell. The control device includes a control unit, a determination value acquisition unit, a diagnosis unit, and a correction unit. The control unit temporarily reduces the oxygen removal capability of the pump cell. The determination value acquisition unit acquires an output ratio of the sensor cell based on an output value of the sensor cell in a state where the oxygen removal capability of the pump cell is temporarily reduced. The diagnosis unit performs deterioration diagnosis of the gas sensor by comparing the output ratio with a determination threshold. The correction unit sets a correction coefficient based on an atmospheric pressure and an oxygen concentration, and also corrects the output ratio using the correction coefficient.

Sensor element, gas sensor, and gas sensor unit

A sensor element (100) including a measurement chamber (89); a pump cell (83) including a solid electrolyte body (69), an inner electrode (101), and an outer electrode (99); and a reference cell (85). At least one electrode contains a noble metal and a component of the solid electrolyte body. In a cross section, the at least one electrode has a noble metal region (205), a solid electrolyte body region (203), and a coexistence region (207) in which the noble metal and the component of the solid electrolyte body coexist. Further, in the cross section, an area ratio SR of the coexistence region is not less than 15.5% and is less than 30%.

SOx CONCENTRATION ACQUIRING APPARATUS OF INTERNAL COMBUSTION ENGINE

A SOx concentration acquiring apparatus of an internal combustion engine of the invention acquires sensor currents as SOx concentration currents after a sensor voltage reaches an oxygen decreasing voltage in a reoxidation voltage decreasing control, acquires the sensor current as a base current when the sensor voltage is equal to or lower than the oxygen decreasing voltage in the reoxidation voltage decreasing control, acquires an integration value of differences between the base current and each of the SOx concentration currents, and acquires a SOx concentration of an exhaust gas discharged from an internal combustion engine on the basis of the integration value.

Compact microelectronic integrated gas sensor

A compact microelectronic gas sensor module includes electrical contacts formed in such a way that they do not consume real estate on an integrated circuit chip. Using such a design, the package can be miniaturized further. The gas sensor is packaged together with a custom-designed Application Specific Integrated Circuit (ASIC) that provides circuitry for processing sensor signals to identify gas species within a sample under test. In one example, the output signal strength of the sensor is enhanced by providing an additional metal surface area in the form of pillars exposed to an electrolytic gas sensing compound, while reducing the overall package size. In some examples, bottom side contacts are formed on the underside of the substrate on which the gas sensor is formed. Sensor electrodes may be electrically coupled to the ASIC directly, or indirectly by vias.

Stabilization of sensor signal in electrochemical gas sensors

An electrochemical gas sensor includes a housing comprising a gas inlet, an electrolyte within the housing, a working electrode in ionic contact with the electrolyte, a counter electrode in ionic contact with the electrolyte and a secondary electrode in ionic contact with the electrolyte. Reaction of target gas at the secondary electrode is less than reaction of target gas at the working electrode. Electronic circuitry of the gas sensor is configured to measure an output from the working electrode and an output from the at least one secondary electrode. A correction factor is determined for correcting the output from the working electrode on the basis of the working electrode output and the secondary electrode output during an assessment in which the electrochemical sensor is exposed to the target gas for a determined period of time.