CN203257550U - Lean burn gasoline engine constant torque self-learning control system provided with NOx absorption reduction catalytic converter - Google Patents

Abstract

The utility model relates to an internal combustion engine lean burn tail gas control technology, in particular to a lean burn gasoline engine constant torque self-learning control system provided with a NOx absorption reduction catalytic converter. The lean burn gasoline engine constant torque self-learning control system comprises an ECU main controller, an engine rotating speed monitoring module, an engine torque monitoring module, an original machine thick burn MAP storage unit, an original machine lean burn MAP storage unit, an auxiliary thick burn MAP storage unit and an auxiliary lean burn MAP storage unit. The original machine thick burn MAP storage unit and the auxiliary thick burn MAP storage unit are connected with the ECU main controller in a double-direction mode. The lean burn gasoline engine constant torque self-learning control system has the advantages that compared with the prior art, through dynamic adjustment of a MAP, optimal adjustment of throttle percentage and a spark advance angle is achieved.

Description

The permanent moment of torsion automatic learning control system of gasoline engine of being furnished with NOx absorbing and reducing catalytic converter

Technical field

The utility model relates to internal-combustion engine Rarefied combustion tail gas control technique, relate to particularly a kind of gasoline engine of realizing being furnished with NOx absorbing and reducing catalytic converter periodically alternate run keep output speed and the constant control system of moment of torsion when lean-burn working state and dense combustion working state.

Background technique

The petrol engine lean burn technology can improve the fuel economy of petrol engine effectively, and the discharging of reduction HC, CO, yet be in the atmosphere of oxygen content surplus due to the tail gas of motor discharge, make traditional triple effect catalytic converter TWC lose efficacy, can't efficiently remove NOx under oxygen-enriched environment.This just needs to adopt the exhaust aftertreatment technology to reduce a large amount of NOx dischargings that produce under lean burn conditions.NOx absorbing and reducing catalytic converter LNT(Lean-NOx-Trap) can effectively reduce the discharging of gasoline engine NOx.Gasoline engine is when adopting NOx absorbing and reducing catalyzed conversion preprocessor LNT work, its periodically alternation in lean-burn working state (NOx adsorptive process) and dense combustion working state (NOx reduction process) so that complete LNT in achieving lean combustion in engine state NOx adsorption and dense combustion state reducing NOx emissions thing process.If merely keep throttle opening constant, only keep certain mixer concentration by fuel injection amount, will inevitably make the external output torque of petrol engine produce larger fluctuation, cause the larger variation of engine speed, make the driveability deterioration of vehicle.Therefore need a kind of gasoline engine that can keep substantially to keep external output speed and the constant control system of moment of torsion when dense rare conversion.

Summary of the invention

The purpose of this utility model is in air-fuel ratio, dense combustion step change procedure, guarantees the automatic learning control system of petrol engine rotational speed and moment of torsion constant output.

The permanent moment of torsion automatic learning control system of gasoline engine of being furnished with NOx absorbing and reducing catalytic converter, definition: during different air fuel ratio A/F, the MAP figure of rotating speed, moment of torsion and throttle opening is former machine MAP figure, and machine MAP figure in its Central Plains can be divided into again the dense combustion of former machine MAP figure and former machine lean-burn MAP figure; Under different air fuel ratio A/F and different ignition advance angle condition take the MAP figure of rotating speed, moment of torsion and throttle opening for auxiliary MAP figure, wherein auxiliary MAP figure can be divided into again auxiliary dense combustion MAP and schemes and assist lean-burn MAP to scheme; Comprise:

ECU master controller 1 is respectively at the connected engine speed monitoring modular 2 of ECU master controller, Engine torque monitoring modular 3, former machine MAP figure storage unit 9, auxiliary MAP figure storage unit 10;

Described former machine MAP figure storage unit comprises: the dense combustion of former machine MAP figure storage unit 4, former machine lean-burn MAP figure storage unit 5;

Described auxiliary MAP figure storage unit comprises: auxiliary dense combustion MAP figure storage unit 6, auxiliary lean-burn MAP figure storage unit 7;

It is two-way the connection between the dense combustion of described former machine MAP figure storage unit, auxiliary dense combustion MAP figure storage unit and ECU master controller, poor according to engine speed the dense combustion of former machine MAP figure storage unit and auxiliary dense combustion MAP figure storage unit are dynamically adjusted the reservation optimal data.

The utility model is with respect to the advantage of prior art: by the dynamic adjustment of MAP figure, realize the optimal adjustment of throttle opening and ignition advance angle, when having realized that dense, phase process is switched, moment of torsion and rotating speed are controlled in driver's acceptable scope; Both guarantee the processing of LNT to NOx, also guaranteed driver or motroist's travelling comfort.

Description of drawings

Fig. 1 is the utility model system authority schematic diagram.In figure, 1 represents the ECU master controller, 2 represent the engine speed monitoring modular, and 3 represent the Engine torque monitoring modular, and 4 represent the dense combustion of former machine MAP figure storage unit, 5 represent former machine lean-burn MAP figure storage unit, the 6 auxiliary dense combustion MAP figure storage unit of representative, the 7 auxiliary lean-burn MAP figure storage unit of representative, 8 represent motor, 9 represent former machine MAP figure storage unit, the 10 auxiliary MAP figure storage unit of representative.

In Fig. 2 embodiment 1, the automatically controlled gasoline engine of CA3GA2 of transformation is 12 o'clock at air fuel ratio A/F, and under each throttle opening that obtains by self study, moment of torsion is with the change curve of rotating speed.

Fig. 3 is that the automatically controlled gasoline engine of CA3GA2 of transformation in embodiment 1 is 20 o'clock at air fuel ratio A/F, and under each throttle opening, moment of torsion is with the change curve of rotating speed.

Embodiment

In conjunction with Fig. 1-3 explanation specific implementation of the present utility model.

Be furnished with the permanent moment of torsion automatic learning control system of gasoline engine of NOx absorbing and reducing catalytic converter, comprise:

ECU master controller 1, the engine speed monitoring modular 2 that is connected with the ECU master controller respectively, Engine torque monitoring modular 3, former machine MAP figure storage unit 9, auxiliary MAP figure storage unit 10;

Described former machine MAP figure storage unit comprises: the dense combustion of former machine MAP figure storage unit 4, former machine lean-burn MAP figure storage unit 5;

Described auxiliary MAP figure storage unit comprises: auxiliary dense combustion MAP figure storage unit 6, auxiliary lean-burn MAP figure storage unit 7.

It is two-way the connection between the dense combustion of described former machine MAP figure storage unit, auxiliary dense combustion MAP figure storage unit and ECU master controller, poor according to engine speed the dense combustion of former machine MAP figure storage unit and auxiliary dense combustion MAP figure storage unit are dynamically adjusted the reservation optimal data.

Control procedure is as follows:

In the periodic step change procedure of engine air-fuel ratio, engine speed monitoring module monitors engine speed changes, Engine torque monitoring module monitors moment of torsion exporting change; At first the ECU master controller calls the MAP figure adjusting joint valve opening in former machine MAP figure storage unit, until the fluctuation absolute value of rotating speed is less than the particular value Q of certain setting, and the torque ripple absolute value is during less than the particular value P of certain setting, and this process is the coarse adjustment process;

Identical before if above-mentioned adjusting can not realize moment of torsion output and switch, the ECU master controller calls the MAP figure operation in auxiliary MAP figure storage unit, until make the moment of torsion output after switching between rare, dense combustion or dense, lean-burn before identical with switching; This process is the thin tuning process.

The dense combustion of described former machine MAP figure, auxiliary dense combustion MAP figure are in dynamic adjustment process,

When by dense combustion regeneration lean-burn adsorptive process; Record the deviation of this process medium speed; With this deviation as input quantity; At motor during with the lean-burn process operation; When calculating next adsorptive process by certain algorithm to the reduction value of air fuel ratio throttle opening and ignition timing; And write down the reduction value of each generation and the deviation of each regenerative process rotating speed; Each deviation is compared; And with the rotating speed deviation in qualified wave range the time each corresponding reduction value scheme as the dense combustion of former machine MAP; The increment graph of auxiliary dense combustion MAP figure stores; The corresponding reduction value of undesirable deviation is rejected; Rule constantly moves in circles according to this.

In the present embodiment: select the automatically controlled gasoline engine of CA3GA2 of transformation, dense combustion air fuel ratio A/F is 12, and lean-burn air fuel ratio A/F is 20; Q=50rpm; P=5N.m, adopting pid algorithm is the basis, uses for reference the principle of fuzzy control and neuron network, finds gradually optimum algorithm in the process of test.

Claims (1)

1. the permanent moment of torsion automatic learning control system of gasoline engine of being furnished with NOx absorbing and reducing catalytic converter, definition: during different air fuel ratio A/F, the MAP figure of rotating speed, moment of torsion and throttle opening is former machine MAP figure, and machine MAP figure in its Central Plains can be divided into again the dense combustion of former machine MAP figure and former machine lean-burn MAP figure; Under different air fuel ratio A/F and different ignition advance angle condition take the MAP figure of rotating speed, moment of torsion and throttle opening for auxiliary MAP figure, wherein auxiliary MAP figure can be divided into again auxiliary dense combustion MAP and schemes and assist lean-burn MAP to scheme; It is characterized in that, comprising:

ECU master controller (1) is respectively at the connected engine speed monitoring modular (2) of ECU master controller, Engine torque monitoring modular (3), former machine MAP figure storage unit (9), auxiliary MAP figure storage unit (10);

Described former machine MAP figure storage unit comprises: the dense combustion of former machine MAP figure storage unit (4), former machine lean-burn MAP figure storage unit (5);

Described auxiliary MAP figure storage unit comprises: auxiliary dense combustion MAP figure storage unit (6), auxiliary lean-burn MAP figure storage unit (7);

It is two-way the connection between the dense combustion of described former machine MAP figure storage unit, auxiliary dense combustion MAP figure storage unit and ECU master controller, poor according to engine speed the dense combustion of former machine MAP figure storage unit and auxiliary dense combustion MAP figure storage unit are dynamically adjusted the reservation optimal data.

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