A control method and device of a nitrogen-oxygen sensor pump unit, a system and a medium

Abstract

The application discloses a control method, device and system of a nitrogen-oxygen sensor pump unit and a medium. The method comprises the following steps: if it is detected that the nitrogen-oxygen sensor pump unit is started, the size relationship between a first deviation value of pump current of a second chamber and a first preset value is compared; if the first deviation value of the pump current of the second chamber is greater than the first preset value, the upper limit value of the Nernst voltage of a first chamber is set as a second preset value; a preset closed-loop control strategy is executed; the oxygen concentration of each chamber of the nitrogen-oxygen sensor pump unit is detected; if the oxygen concentration of each chamber of the nitrogen-oxygen sensor pump unit is within a corresponding first preset range, the upper limit value of the Nernst voltage of the first chamber is set as a third preset value. According to the oxygen concentration of the nitrogen-oxygen sensor pump unit, different upper limit values of the Nernst voltage of the first chamber are set, the oxygen pumping capacity is improved when the oxygen concentration is high, the adjustment pressure and the adjustment time of the subsequent chamber are reduced, and the pump current is prevented from overshooting when the oxygen concentration is normal.

Description

Technical Field

[0001] This invention relates to the field of nitrogen and oxygen sensor technology, and in particular to a control method, device, system and medium for a nitrogen and oxygen sensor pump unit. Background Technology

[0002] The method used by the nitrogen oxide sensor to measure nitrogen oxide concentration involves causing nitrogen oxides to undergo the following decomposition reaction under set oxygen concentration and probe cavity temperature conditions: , This method indirectly measures the concentration of nitrogen oxides in the exhaust gas by measuring the oxygen content produced by the decomposition of nitrogen oxides. To measure the concentration of nitrogen oxides using this method, the oxygen concentration in each chamber of the nitrogen-oxygen sensor (first chamber, second chamber, and third chamber) must be maintained at a set level, ensuring that the oxygen content detected by the third chamber originates entirely from the decomposition of nitrogen oxides.

[0003] Once the nitrogen oxide sensor ceramic chip reaches and stabilizes at the target control temperature, the Sensor Control Unit (SCU) enables closed-loop control of each chamber pump unit. During the initial phase of pump unit activation and the sudden engine fuel cut-off phase, the actual values ​​of the pump current in the second chamber, the Nernst voltage in the second chamber, and the Nernst voltage in the third chamber differ significantly from the set target values. This phase of control can lead to overshoot of the pump current in the first chamber.

[0004] Existing technology sets an upper limit on the Nernst voltage of the first chamber to prevent overshoot of the pump current. This limits the output of a large pump current in the first chamber, hindering the timely pumping out of oxygen and causing excess oxygen to diffuse into the second and third chambers. However, limiting the output of the pump current in the first chamber significantly affects the convergence time of the Nernst voltage, allowing even more oxygen to flow into the third chamber. Since the third chamber generates its pump current based on the oxygen content, outputting the nitrogen and oxygen concentration, the influx of excess oxygen will cause a deviation in the pump current measurement of the third chamber, thus affecting the accuracy of nitrogen and oxygen testing. Summary of the Invention

[0005] This invention provides a control method, device, system, and medium for a nitrogen and oxygen sensor pump unit, which can improve the pumping capacity when the oxygen concentration is too high, reduce the adjustment pressure and adjustment time of the subsequent chamber, and avoid pump current overshoot when the oxygen concentration is normal.

[0006] In a first aspect, embodiments of the present invention provide a control method for a nitrogen and oxygen sensor pump unit, comprising:

[0007] Detect the on / off status of the nitrogen and oxygen sensor pump unit;

[0008] If the nitrogen and oxygen sensor pump unit is detected to be turned on, the first deviation value of the pump current in the second chamber is compared with the first preset value.

[0009] If the first deviation value of the pump current in the second chamber is greater than the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the second preset value; wherein, when the oxygen concentration in the second chamber is greater than the corresponding first preset range, the first deviation value of the pump current in the second chamber is greater than the first preset value, and there is excess unstable oxygen in the nitrogen-oxygen sensor pump unit.

[0010] A preset closed-loop control strategy is executed; wherein, the upper limit of the Nernst voltage of the first chamber is set to the second preset value, and after the preset closed-loop control strategy is executed, the oxygen in the unstable state in the first chamber can be pumped out in time.

[0011] The oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is detected;

[0012] If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, then the upper limit of the Nernst voltage of the first chamber is set to a third preset value. When the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, the nitrogen-oxygen sensor pump unit enters a stable test state. At this time, setting the upper limit of the Nernst voltage of the first chamber to the third preset value can avoid overshooting of the pump current in the first chamber.

[0013] Optionally, the second preset value is greater than the third preset value.

[0014] Optionally, after comparing the magnitude of the first deviation value of the pump current in the second chamber with the first preset value if the nitrogen and oxygen sensor pump unit is detected to be turned on, the method further includes:

[0015] If the first deviation value of the pump current in the second chamber is less than or equal to the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the third preset value.

[0016] Optionally, if the nitrogen and oxygen sensor pump unit is detected to be turned on, comparing the magnitude of the first deviation value of the pump current in the second chamber with the first preset value includes:

[0017] When the nitrogen and oxygen sensor pump unit is detected to be turned on, the absolute value of the deviation between the set value and the actual value of the pump current in the second chamber is obtained after calibration, and the first deviation value is obtained.

[0018] Compare whether the first deviation value is greater than the first preset value.

[0019] Optionally, the step of setting the upper limit of the Nernst voltage of the first chamber to the second preset value if the first deviation value of the pump current in the second chamber is greater than the first preset value includes:

[0020] When the first deviation value of the pump current in the second chamber is detected to be greater than the first preset value, the upper limit value of the Nernst voltage of the first chamber is set to the second preset value according to the voltage value corresponding to the oxygen concentration in the first chamber within the corresponding first preset range.

[0021] Optionally, if the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, then setting the upper limit of the Nernst voltage of the first chamber to a third preset value includes:

[0022] When the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is detected to be within the corresponding first preset range, the upper limit of the Nernst voltage of the first chamber is set to the third preset value based on the voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range.

[0023] Optionally, after detecting the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit, the method further includes:

[0024] If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is outside the corresponding first preset range, the first deviation value of the pump current in the second chamber is compared with the first preset value.

[0025] Optionally, before detecting the on / off state of the nitrogen and oxygen sensor pump unit, the method further includes:

[0026] When engine startup is detected and dew point detection is completed, the ceramic chip is controlled to heat up to the target temperature.

[0027] Optionally, after setting the upper limit of the Nernst voltage of the first chamber to a third preset value if the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, the method further includes:

[0028] Obtain the concentration of nitrogen oxides.

[0029] Secondly, embodiments of the present invention also provide a control device for a nitrogen and oxygen sensor pump unit, comprising:

[0030] An on-state detection module is used to detect the on-state of the nitrogen and oxygen sensor pump unit;

[0031] The current comparison module is used to compare the magnitude of a first deviation value of the pump current in the second chamber with a first preset value if the nitrogen and oxygen sensor pump unit is detected to be turned on.

[0032] The Nernst voltage setting module is used to set the upper limit of the Nernst voltage of the first chamber to a second preset value when the first deviation value of the pump current in the second chamber is greater than the first preset value; wherein, when the oxygen concentration in the second chamber is greater than the corresponding first preset range, the first deviation value of the pump current in the second chamber is greater than the first preset value, and there is excess unstable oxygen in the nitrogen-oxygen sensor pump unit.

[0033] The closed-loop control strategy execution module is used to execute a preset closed-loop control strategy; wherein, the upper limit of the Nernst voltage of the first chamber is set to the second preset value, and after executing the preset closed-loop control strategy, the oxygen in the unstable state in the first chamber can be pumped out in time.

[0034] An oxygen concentration detection module is used to detect the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit;

[0035] The Nernst voltage setting module is also used to set the upper limit of the Nernst voltage of the first chamber to a third preset value when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range; wherein, when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, the nitrogen-oxygen sensor pump unit enters a stable test state, and setting the upper limit of the Nernst voltage of the first chamber to the third preset value at this time can avoid overshooting of the pump current in the first chamber.

[0036] Thirdly, embodiments of the present invention also provide a control system for a nitrogen and oxygen sensor pump unit, comprising: a control device for the nitrogen and oxygen sensor pump unit described in the second aspect, and the nitrogen and oxygen sensor pump unit.

[0037] Fourthly, embodiments of the present invention also provide a storage medium storing computer-readable instructions, characterized in that, when the computer-readable instructions are executed by one or more processors, the one or more processors cause the one or more processors to perform the control method of the nitrogen-oxygen sensor pump unit as described in the first aspect.

[0038] This invention provides a control method, device, system, and medium for a nitrogen oxide sensor pump unit. To ensure that the measurement of nitrogen oxide concentration is not affected by excess oxygen in the nitrogen oxide sensor chamber, during the initial stage of pump unit activation or engine fuel cut-off, when the oxygen concentration in the chamber is high and the first deviation value is large, the upper limit of the Nernst voltage of the first chamber is released, and the upper limit of the Nernst voltage of the first chamber is set to a second preset value. By setting a larger Nernst voltage of the first chamber, a preset closed-loop control strategy is executed to generate a larger pump current in the first chamber, which pumps out excess oxygen in the first chamber as quickly as possible, making the initial stage controllable and reducing the adjustment pressure and adjustment time of subsequent chambers. When entering the stable testing stage, when the oxygen concentration in each chamber of the nitrogen oxide sensor pump unit is within the corresponding first preset range, the deviation of the first deviation value during pump current adjustment is small. The upper limit of the Nernst voltage of the first chamber is set to a third preset value to limit the output of the pump current in the first chamber, avoid overshoot, reduce the impact on the adjustment of other chambers, and ensure that the oxygen concentration in each chamber is quickly closed-loop within the set value range, accurately outputting the real-time nitrogen oxide concentration. The solution of this invention shortens the convergence time of target values ​​in each chamber of the pump unit, allowing the nitrogen oxide sensor to enter the accurate oxygen and nitrogen oxide concentration measurement state earlier. This reduces the time required for engine aftertreatment monitoring and closed-loop control. The main control module, by receiving the output signal from the nitrogen oxide sensor, controls the aftertreatment actuator to perform pollutant purification treatment immediately, thus shortening the emission runaway time and reducing the content of emitted pollutants. Using the control method of the nitrogen oxide sensor pump unit in the above embodiments of this invention, the accuracy of the obtained nitrogen oxide concentration is high.

[0039] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 A flowchart of a control method for a nitrogen and oxygen sensor pump unit provided in an embodiment of the present invention;

[0042] Figure 2 A flowchart illustrating another control method for a nitrogen and oxygen sensor pump unit provided in an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the control device for a nitrogen and oxygen sensor pump unit provided in an embodiment of the present invention;

[0044] Figure 4 The present invention also provides a schematic diagram of the control system of a nitrogen and oxygen sensor pump unit. Detailed Implementation

[0045] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0046] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0047] Figure 1 This is a flowchart illustrating a control method for a nitrogen oxide sensor pump unit according to an embodiment of the present invention. This embodiment is applicable to controlling nitrogen oxide sensor pump units. The method can be executed by a control device for the nitrogen oxide sensor pump unit, which can be implemented in hardware and / or software. (See reference...) Figure 1 The method includes:

[0048] S110, Detect the on / off status of the nitrogen and oxygen sensor pump unit.

[0049] It is understandable that the nitrogen oxide sensor pump unit needs to be activated during the initial stage of enabling the nitrogen oxide sensor pump unit and during the stage of sudden engine fuel cut-off, in order to detect nitrogen oxides in the engine exhaust.

[0050] S120. If the nitrogen and oxygen sensor pump unit is detected to be turned on, compare the first deviation value of the pump current in the second chamber with the first preset value.

[0051] It is understandable that when the nitrogen-oxygen sensor pump unit is detected to be turned on, comparing the first deviation value of the pump current in the second chamber with the first preset value essentially means that, in the initial stage of enabling the nitrogen-oxygen sensor pump unit, by comparing the deviation of the actual value of the pump current in the second chamber with the preset value, it is possible to determine whether there is unstable oxygen in the nitrogen-oxygen sensor pump unit. By comparing the first deviation value of the pump current in the second chamber with the first preset value, the deviation of the actual value of the pump current in the second chamber from the preset value can be obtained.

[0052] Optionally, based on the above embodiments, step S120 includes: when the nitrogen oxygen sensor pump unit is detected to be turned on, obtaining the absolute value of the deviation between the set value and the actual value of the pump current in the second chamber after calibration, to obtain a first deviation value; comparing whether the first deviation value is greater than a first preset value.

[0053] It should be noted that the first preset value can be set by the user according to the user manual of the nitrogen-oxygen sensor pump unit. Since the actual value of the pump current in the second chamber is measured in real time, it is necessary to use the preset anti-shake operation for calibration to stabilize the actual value of the pump current in the second chamber at a certain value. By obtaining the absolute value of the deviation between the set value and the actual value of the pump current in the second chamber after calibration, the obtained first deviation value can more stably determine whether there is unstable oxygen in the nitrogen-oxygen sensor pump unit.

[0054] S130. If the first deviation value of the pump current in the second chamber is greater than the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the second preset value.

[0055] When the oxygen concentration in the second chamber is greater than the corresponding first preset range, the first deviation value of the pump current in the second chamber is greater than the first preset value, and there is excess unstable oxygen in the nitrogen-oxygen sensor pump unit.

[0056] It should be noted that the second preset value and the first preset range can be set by the user according to the user manual of the nitrogen-oxygen sensor pump unit. The first preset range is the range of oxygen concentration when there is no excess oxygen in the nitrogen-oxygen sensor pump unit. The first preset range includes the preset range of oxygen concentration in the first chamber, the preset range of oxygen concentration in the second chamber, and the preset range of oxygen concentration in the third chamber.

[0057] Optionally, based on the above embodiments, step S130 includes:

[0058] When the first deviation value of the pump current in the second chamber is detected to be greater than the first preset value, the upper limit value of the Nernst voltage of the first chamber is set to the second preset value according to the voltage value corresponding to the oxygen concentration in the first chamber within the corresponding first preset range.

[0059] For example, the second preset value can be the maximum voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range.

[0060] It is understandable that when the first deviation value of the pump current in the second chamber is detected to be greater than the first preset value, it indicates that the oxygen concentration in the second chamber is not within the corresponding first preset range. At this time, based on the voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range, the upper limit value of the Nernst voltage in the first chamber is set to the second preset value. This can increase the pump current in the first chamber, promptly pump out the oxygen that has diffused into the first chamber, and prevent oxygen from diffusing into subsequent chambers, thus affecting the measurement accuracy.

[0061] Because of the coupling relationship between the chambers of the nitrogen-oxygen sensor, the atmosphere state of each chamber will affect other chambers through the diffusion process. When the first deviation value of the pump current in the second chamber is detected to be greater than the first preset value, setting a larger Nernst voltage in the first chamber can enable the Nernst closed-loop control to be completed in the first chamber as soon as possible, so that the chambers can reach a dynamic equilibrium state as early as possible, shorten the adjustment time, and enable the pump current in the second chamber to converge to the target value as soon as possible.

[0062] S140, Execute the preset closed-loop control strategy.

[0063] Specifically, the upper limit of the Nernst voltage in the first chamber is set to a second preset value. After executing the preset closed-loop control strategy, the oxygen in the unstable state in the first chamber can be pumped out in a timely manner.

[0064] It should be noted that the preset closed-loop control strategy can be a proportional-integral-derivative (PID) control strategy. Executing the preset closed-loop control strategy can control the system based on the proportional, integral, and derivative of the error generated by comparing the real-time data of the controlled object with the given value.

[0065] S150, Detects the oxygen concentration in each chamber of the nitrogen and oxygen sensor pump unit.

[0066] Understandably, after executing the preset closed-loop control strategy, the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is detected, and the nitrogen-oxygen sensor pump unit can be judged as to whether it has entered a stable test state based on the oxygen concentration in each chamber.

[0067] S160. If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, then the upper limit of the Nernst voltage of the first chamber is set to the third preset value.

[0068] When the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, the nitrogen-oxygen sensor pump unit enters a stable test state. At this time, the upper limit of the Nernst voltage of the first chamber is set to the third preset value, which can avoid overshooting of the pump current in the first chamber.

[0069] It should be noted that the third preset value can be set by the user according to the user manual of the nitrogen and oxygen sensor pump unit.

[0070] Optionally, based on the above embodiments, the second preset value is greater than the third preset value.

[0071] Optionally, based on the above embodiments, step S160 includes:

[0072] When the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is detected to be within the corresponding first preset range, the upper limit of the Nernst voltage of the first chamber is set to a third preset value based on the voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range.

[0073] For example, the third preset value can be the minimum voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range.

[0074] Understandably, when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, the upper limit of the Nernst voltage of the first chamber is set to a third preset value based on the voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range. This can limit the overshoot of the pump current in the first chamber, making the measurement of nitrogen-oxygen concentration faster and more accurate.

[0075] To ensure that the measurement of nitrogen oxide concentration is not affected by excess oxygen in the nitrogen oxide sensor chamber, this embodiment of the invention, in the initial stage of pump unit activation or engine fuel cut-off stage, when the oxygen concentration in the chamber is high and the first deviation value is large, releases the upper limit of the Nernst voltage of the first chamber and sets the upper limit of the Nernst voltage of the first chamber to a second preset value. By setting a larger Nernst voltage of the first chamber, a preset closed-loop control strategy is executed to generate a larger pump current in the first chamber, pumping out excess oxygen in the first chamber as quickly as possible, making the initial stage controllable and reducing the adjustment pressure and adjustment time of subsequent chambers. When entering the stable testing stage, when the oxygen concentration in each chamber of the nitrogen oxide sensor pump unit is within the corresponding first preset range, the deviation of the first deviation value during pump current adjustment is small. The upper limit of the Nernst voltage of the first chamber is then set to a third preset value to limit the output of the pump current of the first chamber, avoiding overshoot and reducing the impact on the adjustment of other chambers, so that the oxygen concentration in each chamber is quickly closed-loop within the set value range, accurately outputting the real-time nitrogen oxide concentration. The solution of this invention shortens the convergence time of the target values ​​in each chamber of the pump unit, allowing the nitrogen oxide sensor to enter the accurate oxygen and nitrogen oxide concentration measurement state earlier. This can shorten the time of engine aftertreatment monitoring and closed-loop control. By receiving the output signal from the nitrogen oxide sensor, the main control module controls the aftertreatment actuator to perform pollutant purification treatment as soon as possible, which can shorten the emission runaway time and reduce the content of emission pollutants.

[0076] Figure 2 A flowchart of another control method for a nitrogen and oxygen sensor pump unit provided in an embodiment of the present invention is shown below. Figure 2 The method includes the following steps:

[0077] S210, Detect the on / off status of the nitrogen and oxygen sensor pump unit.

[0078] S220. If the nitrogen and oxygen sensor pump unit is detected to be turned on, compare the first deviation value of the pump current in the second chamber with the first preset value.

[0079] S230. If the first deviation value of the pump current in the second chamber is greater than the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the second preset value.

[0080] S240, Execute the preset closed-loop control strategy.

[0081] S250, detects the oxygen concentration in each chamber of the nitrogen and oxygen sensor pump unit.

[0082] S260. If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, then the upper limit of the Nernst voltage of the first chamber is set to the third preset value.

[0083] Optionally, based on the above embodiments, after step S220, the method further includes:

[0084] S231. If the first deviation value of the pump current in the second chamber is less than or equal to the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the third preset value.

[0085] It is understandable that when the first deviation value of the pump current in the second chamber is less than or equal to the first preset value, it means that the oxygen concentration in the second chamber is within the first preset range. At this time, setting the upper limit of the Nernst voltage in the first chamber to the third preset value can avoid overshoot.

[0086] Optionally, based on the above embodiments, after step S250, the method further includes:

[0087] S261. If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is outside the corresponding first preset range, compare the magnitude of the first deviation value of the pump current in the second chamber with the first preset value.

[0088] It is understandable that when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is outside the corresponding first preset range, it indicates that there may still be excess oxygen in the nitrogen-oxygen sensor pump unit. At this time, it is necessary to compare the first deviation value of the pump current in the second chamber with the first preset value again, and then execute the steps after step S220.

[0089] Optionally, based on the above embodiments, before step S210, the method further includes:

[0090] S200: When engine start is detected and dew point detection is completed, control the ceramic chip to heat to the target temperature.

[0091] The target temperature is the temperature at which the nitrogen and oxygen sensor pump unit can be turned on, and the specific temperature can be set by the user according to the actual situation.

[0092] Understandably, when engine startup is detected and dew point detection is completed, controlling the ceramic chip to heat to the target temperature enables the nitrogen oxide sensor pump unit to start.

[0093] It should be noted that after step S210, the process further includes: if the nitrogen and oxygen sensor pump unit is not detected to be turned on within a preset time, then the ceramic chip is controlled to continue heating. The preset time can be set by the user according to actual conditions.

[0094] Optionally, based on the above embodiments, after step S260, the method further includes:

[0095] S270, Obtain the concentration of nitrogen oxides.

[0096] To ensure that the measurement of nitrogen oxide concentration is not affected by excess oxygen in the nitrogen oxide sensor chamber, this embodiment of the invention, in the initial stage of pump unit activation or engine fuel cut-off stage, when the oxygen concentration in the chamber is high and the first deviation value is large, releases the upper limit of the Nernst voltage of the first chamber and sets the upper limit of the Nernst voltage of the first chamber to a second preset value. By setting a larger Nernst voltage of the first chamber, a preset closed-loop control strategy is executed to generate a larger pump current in the first chamber, pumping out excess oxygen in the first chamber as quickly as possible, making the initial stage controllable and reducing the adjustment pressure and adjustment time of subsequent chambers. When entering the stable testing stage, when the oxygen concentration in each chamber of the nitrogen oxide sensor pump unit is within the corresponding first preset range, the deviation of the first deviation value during pump current adjustment is small. The upper limit of the Nernst voltage of the first chamber is then set to a third preset value to limit the output of the pump current of the first chamber, avoiding overshoot and reducing the impact on the adjustment of other chambers, so that the oxygen concentration in each chamber is quickly closed-loop within the set value range, accurately outputting the real-time nitrogen oxide concentration. The solution of this invention shortens the convergence time of target values ​​in each chamber of the pump unit, allowing the nitrogen oxide sensor to enter the accurate oxygen and nitrogen oxide concentration measurement state earlier. This reduces the time required for engine aftertreatment monitoring and closed-loop control. The main control module, by receiving the output signal from the nitrogen oxide sensor, controls the aftertreatment actuator to perform pollutant purification treatment immediately, thus shortening the emission runaway time and reducing the content of emitted pollutants. Using the control method of the nitrogen oxide sensor pump unit in the above embodiments of this invention, the accuracy of the obtained nitrogen oxide concentration is high.

[0097] Figure 3 This is a schematic diagram of the control device for a nitrogen and oxygen sensor pump unit provided in an embodiment of the present invention, with reference to... Figure 3 The device includes: an on-state detection module 310, a current comparison module 320, a Nernst voltage setting module 330, a closed-loop control strategy execution module 340, and an oxygen concentration detection module 350.

[0098] The on-state detection module 310 is used to detect the on-state of the nitrogen-oxygen sensor pump unit. The current comparison module 320, if the nitrogen-oxygen sensor pump unit is detected to be on, compares the first deviation value of the pump current in the second chamber with a first preset value. The Nernst voltage setting module 330, when the first deviation value of the pump current in the second chamber is greater than the first preset value, sets the upper limit of the Nernst voltage in the first chamber to a second preset value. Specifically, when the oxygen concentration in the second chamber is greater than the corresponding first preset range, the first deviation value of the pump current in the second chamber is greater than the first preset value, indicating the presence of excess unstable oxygen within the nitrogen-oxygen sensor pump unit. The closed-loop control strategy execution module 340 is used to execute a preset closed-loop control strategy; wherein, by setting the upper limit of the Nernst voltage in the first chamber to the second preset value, the execution of the preset closed-loop control strategy enables the timely pumping out of the unstable oxygen in the first chamber. The oxygen concentration detection module 350 is used to detect the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit. The Nernst voltage setting module 330 is also used to set the upper limit of the Nernst voltage of the first chamber to a third preset value when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range; wherein, when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, the nitrogen-oxygen sensor pump unit enters a stable test state, and setting the upper limit of the Nernst voltage of the first chamber to the third preset value at this time can avoid overshooting of the pump current in the first chamber.

[0099] The control device for the nitrogen and oxygen sensor pump unit provided in this embodiment of the invention is used to implement the control method for the nitrogen and oxygen sensor pump unit provided in the above embodiments. For details not described in detail in this embodiment, please refer to the control method for the nitrogen and oxygen sensor pump unit provided in the above embodiments. The control device for the nitrogen and oxygen sensor pump unit provided in this embodiment of the invention has the same beneficial effects as the control method for the nitrogen and oxygen sensor pump unit provided in the above embodiments.

[0100] Figure 4 This invention also provides a schematic diagram of the control system for a nitrogen and oxygen sensor pump unit, as shown in the embodiments of the present invention. Figure 4 The system includes: a control device 410 for the nitrogen and oxygen sensor pump unit and a nitrogen and oxygen sensor pump unit 420 as described in the above embodiments.

[0101] This invention also provides a storage medium storing computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to perform the control method of the nitrogen and oxygen sensor pump unit described above.

[0102] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0103] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A control method for a nitrogen-oxygen sensor pump unit, the nitrogen-oxygen sensor pump unit comprising a first chamber, a second chamber, and a third chamber; characterized in that, include: Detect the on / off status of the nitrogen and oxygen sensor pump unit; If the nitrogen and oxygen sensor pump unit is detected to be turned on, the first deviation value of the pump current in the second chamber is compared with the first preset value. If the first deviation value of the pump current in the second chamber is greater than the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the second preset value; the second preset value is the maximum voltage value corresponding to the oxygen concentration in the first chamber within the corresponding first preset range; wherein, the first preset range is the range of oxygen concentration when there is no excess unstable oxygen in the nitrogen-oxygen sensor pump unit, and the first preset range includes the preset range of oxygen concentration in the first chamber, the preset range of oxygen concentration in the second chamber, and the preset range of oxygen concentration in the third chamber; A preset closed-loop control strategy is executed to promptly pump out the oxygen in the unstable state from the first chamber; The oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is detected; If the oxygen concentration in each chamber of the nitrogen and oxygen sensor pump unit is within the corresponding first preset range, then the upper limit of the Nernst voltage of the first chamber is set to the third preset value to avoid overshooting of the pump current of the first chamber. The second preset value is greater than the third preset value; the nitrogen oxide concentration is obtained based on the oxygen content of the third chamber.

2. The control method for the nitrogen and oxygen sensor pump unit according to claim 1, characterized in that, After comparing the first deviation value of the pump current in the second chamber with the first preset value if the nitrogen and oxygen sensor pump unit is detected to be turned on, the method further includes: If the first deviation value of the pump current in the second chamber is less than or equal to the first preset value, then the upper limit value of the Nernst voltage in the first chamber is set to the third preset value.

3. The control method for the nitrogen and oxygen sensor pump unit according to claim 1 or 2, characterized in that, If the nitrogen and oxygen sensor pump unit is detected to be turned on, comparing the first deviation value of the pump current in the second chamber with the first preset value includes: When the nitrogen and oxygen sensor pump unit is detected to be turned on, the absolute value of the deviation between the set value and the actual value of the pump current in the second chamber is obtained after calibration, and the first deviation value is obtained. Compare whether the first deviation value is greater than the first preset value.

4. The control method for the nitrogen and oxygen sensor pump unit according to claim 1, characterized in that, If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, then setting the upper limit of the Nernst voltage of the first chamber to a third preset value includes: When the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is detected to be within the corresponding first preset range, the upper limit of the Nernst voltage of the first chamber is set to the third preset value based on the voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range.

5. The control method for the nitrogen and oxygen sensor pump unit according to claim 1, characterized in that, After detecting the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit, the method further includes: If the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is outside the corresponding first preset range, the first deviation value of the pump current in the second chamber is compared with the first preset value.

6. The control method for the nitrogen and oxygen sensor pump unit according to claim 1, characterized in that, Before detecting the on / off state of the nitrogen and oxygen sensor pump unit, the method further includes: When engine startup is detected and dew point detection is completed, the ceramic chip is controlled to heat up to the target temperature.

7. A control device for a nitrogen-oxygen sensor pump unit, used to execute the control method for the nitrogen-oxygen sensor pump unit according to any one of claims 1 to 6, characterized in that, include: An on-state detection module is used to detect the on-state of the nitrogen and oxygen sensor pump unit; The current comparison module is used to compare the magnitude of a first deviation value of the pump current in the second chamber with a first preset value if the nitrogen and oxygen sensor pump unit is detected to be turned on. A Nernst voltage setting module is used to set the upper limit of the Nernst voltage of the first chamber to a second preset value when the first deviation value of the pump current in the second chamber is greater than the first preset value; the second preset value is the maximum voltage value corresponding to the oxygen concentration in the first chamber being within the corresponding first preset range; wherein, the first preset range is the range of oxygen concentration when there is no excess unstable oxygen in the nitrogen-oxygen sensor pump unit, and the first preset range includes the preset range of oxygen concentration in the first chamber, the preset range of oxygen concentration in the second chamber, and the preset range of oxygen concentration in the third chamber; a closed-loop control strategy execution module is used to execute a preset closed-loop control strategy to pump out the unstable oxygen in the first chamber in a timely manner; An oxygen concentration detection module is used to detect the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit; The Nernst voltage setting module is also used to set the upper limit of the Nernst voltage of the first chamber to a third preset value when the oxygen concentration in each chamber of the nitrogen-oxygen sensor pump unit is within the corresponding first preset range, so as to avoid overshooting of the pump current of the first chamber; the second preset value is greater than the third preset value. The control device obtains the nitrogen oxide concentration based on the oxygen content in the third chamber.

8. A control system for a nitrogen and oxygen sensor pump unit, characterized in that, include: The control device for the nitrogen and oxygen sensor pump unit according to claim 7, and the nitrogen and oxygen sensor pump unit.

9. A storage medium storing computer-readable instructions, characterized in that, When the computer-readable instructions are executed by one or more processors, the one or more processors cause the one or more processors to perform the control method of the nitrogen and oxygen sensor pump unit as described in any one of claims 1-6.

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