CN202391525U - Device for post treatment of exhaust emission of diesel engine - Google Patents

Abstract

The implementation mode of the utility model relates to a device for post treatment of exhaust emission of a diesel engine, and in particular relates to a device applied to the SCR (selective catalytic reduction) system of the diesel engine according to the implementation mode of the utility model. The SCR system comprises a catalyzing device which is used for converting nitric oxide emitted by the diesel engine by utilizing ammonia. The device comprises an acquiring device and a determining device, wherein the acquiring device is coupled to the catalyzing device and is used for acquiring the measurement value of at least one working condition of the catalyzing device; and the determining device is coupled to the acquiring device and is used for determining the ammonia storage capacity of the catalyzing device according to the acquired measurement value so as to determine the ammonia surface coverage rate of the catalyzing device. According to the scheme of the utility model, the ammonia surface coverage rate and the ammonia storage capacity of the SCR catalyzing device can be more exactly evaluated.

Description

The equipment that is used for the toxic emission reprocessing of DENG

Technical field

The mode of execution of the utility model relates generally to DENG, more specifically, relates to the equipment of the toxic emission reprocessing that is used for DENG.

Background technique

In present DENG field, SCR (SCR) is the after-treatment system that the waste gas of engine emission is handled in a kind of important being used to.The SCR after-treatment system generally includes: aqueous solution of urea storage tank, feedway, measuring apparatus, injection apparatus, catalyst converter and temperature and exhaust sensor etc.The basic functional principle of SCR after-treatment system is: waste gas is discharged from the back from engine turbine and gets into the exhaust fixed tube; On the exhaust fixed tube, urea measuring and injecting device is installed; Spray into aqueous solution of urea, urea at high temperature takes place to generate ammonia (NH after hydrolysis and the pyrolytic reaction ₃).Catalyst converter utilizes urea to convert the oxynitrides in the waste gas (NOx) to nitrogen (N as reducing agent ₂) and water.

In the SCR after-treatment system, control urea-spray amount is most important.Spray too much urea and can produce the ammonia leakage, and the urea that sprays very little will cause lower oxynitrides NOx conversion efficiency.In order to design SCR after-treatment system urea-spray control strategy, need to confirm the status information of SCR reprocessing catalysis system.In the prior art, can utilize sensor in real time to measure temperature, air mass flow, NOx concentration, ammonia concentration.Yet, can't carry out directly and accurately measuring to catalytic carrier ammonia surface coverage in practice at present.

Be appreciated that catalytic carrier ammonia surface coverage will directly influence oxynitrides NOx and the concentration of ammonia in the waste gas, and the concentration of oxynitrides NOx in the waste gas and ammonia is two most important states to the design of SCR reprocessing urea-spray amount controller.The design of SCR reprocessing urea-spray amount controller can reach oxynitrides NOx concentration and the minimum target of ammonia leakage in the waste gas through control catalytic carrier ammonia surface coverage.

Because catalytic carrier ammonia surface coverage can not be used conventional sensor measurement, so device that must design special is confirmed it or claimed estimation.This device is commonly called visualizer in the art.The state observer of existing catalytic carrier ammonia surface coverage mainly comprises linear visualizer and based on the visualizer of Kalman (Kalman) filtering.

On the other hand, the ammonia storage capacity of catalyst converter also is the factor that SCR reprocessing urea-spray amount controller must be considered.At present, in the SCR after-treatment system of control, ammonia storage capacity is assumed to be constant usually.Yet research shows that SCR reprocessing catalyst converter ammonia storage capacity reduces along with the aging of SCR reprocessing catalyst converter.It has been generally acknowledged that when time and temperature variation, SCR reprocessing catalyst converter ammonia storage capacity has very high uncertainty.Just because of this, just select SCR reprocessing catalytic carrier ammonia surface coverage to design urea-spray amount robust controller as controlled variable.

According to the definition of SCR reprocessing catalytic carrier ammonia surface coverage, there are inverse relation in ammonia storage capacity and ammonia surface coverage.Therefore, if select the ammonia surface coverage, then ammonia storage capacity must can be confirmed as controlled variable.And, the health status of present emission regulation demands online system failure diagnosis (OBD) monitoring SCR after-treatment system.Ammonia storage capacity is the key factor that reflects that directly SCR is aging.Estimate that SCR reprocessing catalyst converter ammonia storage capacity is that OBD confirms that SCR health status is essential.The state observer of existing ammonia storage capacity comprises the visualizer based on Kalamn filtering.

The state Observer Design of existing ammonia surface coverage and ammonia storage capacity based on Kalamn filtering be in supposition since the ammonia storage capacity dynamics that changes of the aging slow time that causes of SCR catalyst converter or synthermal relevant fast the time ammonia storage capacity dynamics of change design.The shortcoming of this design is: the kinetics mechanism of ammonia storage capacity is still uncertain, and actual ammonia storage capacity dynamics is much complicated possibly.

Therefore, in the prior art, need a kind of more efficiently solution to come to confirm adaptively SCR reprocessing carrier ammonia surface coverage and ammonia storage capacity.

The model utility content

In order to overcome the above-mentioned defective that exists in the existing technology, the mode of execution of the utility model provides a kind of in the SCR after-treatment system, confirm adaptively the carrier ammonia surface coverage of catalyst converter and the equipment of ammonia storage capacity.

Aspect of the utility model, the equipment that uses in a kind of SCR at DENG (SCR) system is provided, this SCR system comprises that catalyst converter transforms the nitrogen oxide of this diesel engine emissions to utilize ammonia.This equipment comprises: obtaining device, and it is coupled to said catalyst converter, and configuration is used to obtain the measured value of this at least one operating mode of catalyst converter; And definite device, it is coupled to said obtaining device, and configuration is used for confirming that based on this measured value that obtains the ammonia storage capacity of this catalyst converter is so that confirm the ammonia surface coverage of this catalyst converter.

According to some mode of execution of the utility model, confirm that device comprises: unite definite device, configuration is used for based on this measured value that obtains, and confirms the ammonia surface coverage of this catalyst converter together in company with the ammonia storage capacity of this catalyst converter.Alternatively; Unite and confirm that device comprises: based on definite device of model; Configuration is used for said measured value as independent variable, through using the reaction model of the chemical reaction characteristic that characterizes said catalyst converter, confirms the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter.

According to some mode of execution of the utility model, further comprise based on definite device of model: computing device, configuration is used for calculating according to this measured value that obtains the Observed value of at least one operating mode; And first confirm device, and configuration is used for based on said reaction model, uses said measured value and said Observed value to confirm the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter.

According to some mode of execution of the utility model, obtaining device comprise following at least one: the first concentration obtaining device, configuration is used for obtaining the nitrous oxides concentration of this catalyst converter; The second concentration obtaining device, configuration is used for obtaining the ammonia concentration of this catalyst converter; And the temperature obtaining device, configuration is used for obtaining the temperature of this catalyst converter.

It will be recognized by those skilled in the art through the hereinafter description; Through adopting the mode of execution of the utility model; When confirming based on the operating mode of the catalyst converter that measures or claiming to estimate the ammonia surface coverage of catalyst converter; The ammonia storage capacity of catalyst converter (or claim storage ammonia ability) can be not for another example in the existing technology that kind be assumed that constant all the time, or confirm based on specific dynamics.On the contrary, the mode of execution of the utility model is not done any hypothesis to the dynamics of ammonia storage capacity, and it can be that constant also can be a variable.Especially, can confirm the ammonia storage volume and the ammonia surface coverage of catalyst converter simultaneously based on the Chemical Reaction Model of catalyst converter.

The physical features that ammonia storage volume of confirming in this way and ammonia surface coverage can reflect the SCR catalyst converter more truly, exactly.In addition, the solution of the utility model proposition is easy to realize and operation in practice.

Description of drawings

Through detailed description with reference to the advantages hereinafter, above-mentioned and other purposes of the utility model mode of execution, the feature and advantage easy to understand that will become.In the accompanying drawings, show the plurality of embodiments of the utility model with exemplary and nonrestrictive mode, wherein:

Fig. 1 shows the block diagram according to the equipment 100 that is used for using in the SCR system of the utility model illustrative embodiments;

Fig. 2 shows the block diagram according to the equipment 200 that is used for using in the SCR system of the utility model illustrative embodiments;

Fig. 3 shows the block diagram of confirming device of uniting according to the utility model illustrative embodiments;

Fig. 4 shows the operation of equipment flow chart that uses in the SCR system of being used for according to the utility model illustrative embodiments.

In the accompanying drawings, identical or corresponding label is represented identical or corresponding part.

Embodiment

The principle and the spirit of the utility model are described below with reference to some illustrative embodiments.Should be appreciated that providing these mode of executions only is in order those skilled in the art can be understood better and then to realize the utility model, and be not the scope that limits the utility model by any way.

Notice that in the application's context, employed term " parameter " expression is any can indicate the value of physical quantity of (target or reality) physical state or the operation conditions of DENG.And in this article, " parameter " physical quantity represented with it can be exchanged use.For example, " parameter of indication concentration " has the implication that is equal in this article with " concentration ".In addition, employed term " obtains " and comprises various means known at present or that develop in the future, and for example measure, read, estimate, estimate, or the like.

Below with reference to some representative embodiments of the utility model, principle of explained in detail the utility model and spirit.At first with reference to figure 1, it shows the schematic representation of the equipment 100 that is used for using in selective reduction reaction SCR system.

As stated, the SCR system comprises catalyst converter.Catalyst converter utilizes urea to convert the oxynitrides in the waste gas of engine emission (NOx) to nitrogen (N as reducing agent usually ₂) and water.As shown in Figure 1, equipment 100 comprises obtaining device 102, and it can be coupled to the catalyst converter in the SCR system, and configuration is used to obtain the measured value of at least one operating mode of catalyst converter.In addition, equipment 100 also comprises confirms device 104, and it is coupled to obtaining device 102, and configuration is used for confirming that based on the said measured value that obtains the ammonia storage capacity of said catalyst converter is so that confirm the ammonia surface coverage of said catalyst converter.Specific operation and characteristic about obtaining device 102 and definite device 104 will be explained below.

Below with reference to figure 2, it shows the schematic representation of the equipment 200 that is used for using in selective reduction reaction SCR system.Equipment 200 is that the concrete and refinement of above-described equipment 100 realizes.Equipment 200 comprises obtaining device 202 and the definite device 204 that is coupled with it, and it corresponds respectively to above-described device 102 and 104.To combine concrete example that the characteristic of equipment 200 is described in detail below.

In some mode of execution of the utility model, can confirm the ammonia storage capacity and the ammonia surface coverage of catalyst converter based on following at least one working condition measuring value: the nitrous oxides concentration in the catalyst converter, the ammonia concentration in the catalyst converter; And the temperature in the catalyst converter.Correspondingly, in these mode of executions, obtaining device 202 can comprise following at least one: the first concentration obtaining device 2022, configuration is used for obtaining the nitrous oxides concentration of catalyst converter; The second concentration obtaining device 2024, configuration is used for obtaining the ammonia concentration of catalyst converter; And temperature obtaining device 2026, configuration is used for obtaining the temperature of catalyst converter.

As an example, the first concentration obtaining device 2022 and the second concentration obtaining device 2024 can dispose the measured value that is used to utilize appropriate sensor to obtain nitrous oxides concentration and the measured value of ammonia concentration respectively.Equally, temperature obtaining device 2026 for example can dispose and be used to use suitable temperature transducer to obtain the measured temperature of catalyst converter.Especially, according to some mode of execution, the entry end of catalyst converter and outlet end can be respectively arranged with upstream temperature sensor and downstream temperature sensor.At this moment, the temperature obtaining device 2026 in the obtaining device 202 of equipment 200 can be estimated the temperature of catalyst converter based on the measured value of upstream temperature sensor and downstream temperature sensor.For example, can with the temperature computation of catalyst converter the arithmetic mean value or the weighted mean value of upstream temperature and downstream temperature.

Notice that above-described only is some possible example, other any proper technology means known at present or exploitation in the future all can be used for obtaining the working condition measuring value of catalyst converter.The scope of the utility model is unrestricted in this regard.

In an optional mode of execution of the utility model, can confirm the ammonia storage capacity and the ammonia surface coverage of catalyst converter simultaneously according to a kind of mode of associating.In other words, when confirming the ammonia surface coverage of catalyst converter, ammonia storage capacity no longer must be constant, but is determined as dependent variable with the ammonia surface coverage alternatively.Correspondingly, in such mode of execution, definite device 204 of equipment 200 can comprise uniting confirms device 2042, and its configuration is used for based on the said measured value that obtains, and confirms the ammonia surface coverage of catalyst converter together in company with the ammonia storage capacity of catalyst converter.

Unite and confirm that device 2042 can confirm simultaneously the ammonia storage capacity and the ammonia surface coverage of catalyst converter through any suitable mode.For example; In some mode of execution of the utility model; Unite and confirm that device can comprise the definite device (not shown) based on model; Its configuration is used for said measured value as independent variable, through using the model of the chemical reaction characteristic that characterizes said catalyst converter, confirms the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter.

In such mode of execution, can set up the reaction model (or abbreviation " reaction model ") of the chemical reaction characteristic that characterizes the SCR catalyst converter through any suitable means of developing known or future at present.Based on this reaction model, confirm that device 204 will be used as independent variable by the catalyst converter working condition measuring value that obtaining device 202 obtains, so that confirm to estimate in other words the ammonia storage capacity and the ammonia surface coverage of catalyst converter simultaneously.In other words, the ammonia storage capacity of catalyst converter and ammonia surface coverage are in this reaction model, to serve as dependent variable.To describe the concrete example of a reaction model below, wherein, the independent variable of this reaction model comprises nitrous oxides concentration, ammonia concentration and the temperature in the catalyst converter.

In this mode of execution, as indicated above, temperature obtaining device 2026 for example can obtain the measured value of catalyst temperature through following mode:

$T=\frac{T_{\mathrm{Us}}+T_{\mathrm{Ds}}}{2}---\left(1\right)$

T wherein _UsAnd T _DsBe respectively the upstream temperature and the downstream temperature of catalyst converter.

The ammonia storage capacity of catalyst converter is expressed as Ω; And the ammonia surface coverage of catalyst converter being expressed as

can set up the model that characterizes chemical reaction characteristic in the catalyst converter through following mode; That is reaction model:

${\stackrel{\·}{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}=c_{{\mathrm{NH}}_3}{a}_3\left(T\right)(1-{\mathrm{\Θ}}_{{\mathrm{NH}}_3})-[a_4\left(T\right)+a_5\left(T\right)c_{{\mathrm{NO}}_x}+a_6\left(T\right)]{\mathrm{\Θ}}_{{\mathrm{NH}}_3}---\left(2\right)$

${\stackrel{\·}{c}}_{{\mathrm{NO}}_x}=a_1{n}_{{\mathrm{NO}}_x,\mathrm{in}}^{*}-c_{{\mathrm{NO}}_x}(a_0{a}_1{m}_{\mathrm{EG}}^{*}T+a_5\left(T\right)\mathrm{\Ω}{\mathrm{\Θ}}_{{\mathrm{NH}}_3})---\left(3\right)$

${\stackrel{\·}{c}}_{{\mathrm{NH}}_3}=a_1{n}_{{\mathrm{NH}}_3,\mathrm{in}}^{*}-c_{{\mathrm{NH}}_3}[a_0{a}_1{m}_{\mathrm{EG}}^{*}T+a_3\left(T\right)\mathrm{\Ω}(1-{\mathrm{\Θ}}_{{\mathrm{NH}}_3})]+a_4\left(T\right){\mathrm{\Ω\Θ}}_{{\mathrm{NH}}_3}---\left(4\right)$

In formula (3)-(4), from temperature T, the nitrous oxides concentration measured value c of obtaining device 202 _NOxWith ammonia concentration measurement c _NH3Be independent variable.The definition of other constants is following:

$a_0=\frac{R_{S,\mathrm{EG}}}{P_{\mathrm{amb}}};$

R _{S, EG}: engine exhaust gas constant (J/kgK);

P _Amb: external pressure (pa);

$a_1=\frac{n_{\mathrm{Cell}}}{\mathrm{\ϵ}{V}_C};$

n _Cell: catalyst converter infinitesimal number;

V _C: catalyst converter volume (m ³);

ε: void ratio;

$a_3\left(T\right)=S_C{\mathrm{\α}}_{\mathrm{Prob}}\sqrt{\frac{\mathrm{RT}}{2\mathrm{\π}{\mathrm{Mr}}_{{\mathrm{NH}}_3}}};$

c _S: ammonia absorbing capacity, catalyst converter surface active atomic concentration (mol/m ³);

S _C: the area (m of surface activity atom ²/ mol);

α _Prob: sticking probability;

R: gas constant (J/molK)

NH3 molecular weight

m ^* _EG: exhaust mass flow (kg/s)

$a_4\left(T\right)=k_{\mathrm{Des}}{e}^{\left(\frac{-E_{a,\mathrm{Des}}}{\mathrm{RT}}\right)}$

k _Des: NH3 desorption reactive rate (mol/m ³S);

E _ADes: NH3 desorption frequency factor;

$a_5\left(T\right)={\mathrm{RTk}}_{\mathrm{SCR}}{e}^{\left(\frac{-E_{a,\mathrm{SCR}}}{\mathrm{RT}}\right)}$

k _SCR: SCR chemical reaction frequency factor (m ²/ Ns)

E _ASCR: SCR chemical reaction activation energy (J/mol)

$a_6\left(T\right)=k_{\mathrm{Ox}}{e}^{\left(\frac{-E_{a,\mathrm{Ox}}}{\mathrm{RT}}\right)}$

k _OX: NH3 oxidation reaction frequency factor (m ²/ Ns)

E _AOX: NH3 oxidation reaction activation energy (J/mol)

Nitrous oxides concentration in the former machine discharging of

diesel engine

The ammonia concentration that

urea pump ejects

Notice that preceding text are not intended to limit the scope of the utility model through the example of Chemical Reaction Model that is only used for characterizing catalyst converter of formula (2)-(4) foundation.Can use any suitable mode, be independent variable with the working condition measuring value of SCR catalyst converter, is dependent variable with the ammonia storage capacity and the ammonia surface coverage of catalyst converter, sets up the Chemical Reaction Model of SCR catalyst converter.

Based on the reaction model (for example, above-described exemplary reaction model) of the SCR catalyst converter of setting up, can confirm the ammonia storage capacity and the ammonia surface coverage of catalyst converter based on definite device of model through the set of equation of finding the solution representation model.For example, consider that still exemplary catalyst converter reaction model that preceding text pass through to set up formula (2)-(4) as an example.Based on formula (2)-(4), can derive following vector equation:

$\stackrel{\·}{x}=\mathrm{Ax}+\mathrm{\φ}(x,u)+\mathrm{\Ωf}\left(x\right)---\left(5\right)$

Wherein

serves as controlled quentity controlled variable, and wherein:

$x=\left\{\begin{array}{c}{\mathrm{\Θ}}_{{\mathrm{NH}}_3}\\ c_{{\mathrm{NO}}_X}\\ c_{{\mathrm{NH}}_3}\end{array}\right\}$

$A=\left[\begin{array}{ccc}-(a_4\left(T\right)+a_1)& 0& 0\\ 0& -a_0{a}_1{m}_{\mathrm{EG}}^{*}T& 0\\ 0& 0& -a_0{a}_1{m}_{\mathrm{EG}}^{*}T\end{array}\right]$

$\mathrm{\φ}(x,u)=\left\{\begin{array}{c}{c}_{{\mathrm{NH}}_3}{a}_3\left(T\right)(1-{\mathrm{\Θ}}_{{\mathrm{NH}}_3})-a_5\left(T\right){\mathrm{\Θ}}_{{\mathrm{NH}}_3}{c}_{{\mathrm{NO}}_x}\\ a_1{n}_{{\mathrm{NO}}_x,\mathrm{in}}^{*}\\ a_{1}u\end{array}\right\}$

$f\left(x\right)=\left\{\begin{array}{c}0\\ -a_5\left(T\right){\mathrm{\Θ}}_{{\mathrm{NH}}_3}{c}_{{\mathrm{NO}}_x}\\ a_4\left(T\right){\mathrm{\Θ}}_{{\mathrm{NH}}_3}-a_3\left(T\right)c_{{\mathrm{NH}}_3}(1-{\mathrm{\Θ}}_{{\mathrm{NH}}_3})\end{array}\right\}$

Here, in order to confirm the ammonia storage capacity and the ammonia surface coverage of catalyst converter more exactly simultaneously, according to some mode of execution of the utility model, the measured value of the catalyst converter operating mode that can obtain obtaining device 202 is further handled.For example, uniting the definite device of confirming in the device 2042 based on model can comprise: computing device (not shown), its configuration are used for calculating according to the measured value that obtains the Observed value of corresponding operating mode; And first confirm the device (not shown), and its configuration is used for based on reaction model, and the measured value of applying working condition and Observed value are confirmed the ammonia storage capacity of catalyst converter and the ammonia surface coverage of catalyst converter.

Particularly, as an example, based on definite device of model can operate make nonlinear function φ (x, u) and f (x) satisfy local Li Puxisi (Lipchitz) condition, then have:

$\left|\right|\mathrm{\φ}(x,u)-\mathrm{\φ}(\hat{x},u)\left|\right|\≤{\mathrm{\α}}_1\left|\right|x-\hat{x}\left|\right|$

$\left|\right|f\left(x\right)-f\left(\hat{x}\right)\left|\right|\≤{\mathrm{\α}}_2\left|\right|x-\hat{x}\left|\right|$

α wherein ₁And α ₂It is constant.Consider following Liapunov (Lyapunov) function simultaneously:

$V=\frac{1}{2}{e}^{T}e+\frac{1}{2}\mathrm{\ρ}{\widetilde{\mathrm{\Ω}}}^2$

Wherein

and

is the state observation value of x;

is the estimated value of Ω, and ρ＞0th, the weight factor constant.

Thus, can confirm the Observed value of each working condition measuring value and correspondingly confirm ammonia storage capacity and the ammonia surface coverage of catalyst converter through following mode based on definite device of model, feasible:

${\stackrel{\stackrel{\·}{^}}{T}}_{\mathrm{Ds}}=a_7{m}_{\mathrm{EG}}^{*}(T_{\mathrm{Us}}-{\hat{T}}_{\mathrm{Ds}})-a_9({\hat{T}}_{\mathrm{Ds}}^4-T_{\mathrm{amb}}^4)+L_1(T_{\mathrm{Us}}-{\hat{T}}_{\mathrm{Us}})---\left(6\right)$

$\hat{T}=\frac{T_{\mathrm{Us}}+T_D}{2}---\left(7\right)$

${\stackrel{\stackrel{\·}{^}}{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}=[a_4\left(\hat{T}\right)+a_6\left(\hat{T}\right)]{\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}+{\hat{c}}_{N{H}_3}{a}_3\left(\hat{T}\right)(1-{\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3})-a_5\left(\hat{T}\right){\hat{c}}_{{\mathrm{NO}}_x}{\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}---\left(8\right)$

${\stackrel{\stackrel{\·}{^}}{c}}_{{\mathrm{NO}}_x}=-{\hat{c}}_{{\mathrm{NO}}_x}{a}_0{a}_1{m}_{\mathrm{EG}}^{*}\hat{T}+a_1{n}_{{\mathrm{NO}}_x,\mathrm{in}}^{*}-\widehat{\mathrm{\Ω}}{a}_5\left(\hat{T}\right){\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}{\hat{c}}_{{\mathrm{NO}}_x}+$ (9)

$L_1(c_{{\mathrm{NO}}_x}-{\hat{c}}_{{\mathrm{NO}}_x})-{\mathrm{\λ}}_1\mathrm{sign}(c_{{\mathrm{NO}}_x}-{\hat{c}}_{{\mathrm{NO}}_x})$

${\stackrel{\stackrel{\·}{^}}{c}}_{{\mathrm{NH}}_3}=-{\hat{c}}_{{\mathrm{NH}}_3}{a}_0{a}_1{m}_{\mathrm{EG}}^{*}\hat{T}+a_{1}u+\widehat{\mathrm{\Ω}}{c}_{{\mathrm{NH}}_3}[a_4\left(\hat{T}\right){\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}-a_3\left(\hat{T}\right){\hat{c}}_{{\mathrm{NH}}_3}(1-{\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3})]$ (10)

${+L}_2(c_{{\mathrm{NH}}_3}-{\hat{c}}_{{\mathrm{NH}}_3})-{\mathrm{\λ}}_2\mathrm{sign}(c_{{\mathrm{NH}}_3}-{\hat{c}}_{{\mathrm{NH}}_3})$

$\stackrel{\stackrel{\·}{^}}{\mathrm{\Ω}}=-\frac{1}{\mathrm{\ρ}}\{-a_5\left(\hat{T}\right){\hat{c}}_{{\mathrm{NO}}_x}{\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}(c_{{\mathrm{NO}}_x}-{\hat{c}}_{{\mathrm{NO}}_x})+$ (11)

$[a_4\left(\hat{T}\right){\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3}-a_3\left(\hat{T}\right){\hat{c}}_{{\mathrm{NH}}_3}(1-{\widehat{\mathrm{\Θ}}}_{{\mathrm{NH}}_3})](c_{{\mathrm{NH}}_3}-{\hat{c}}_{{\mathrm{CH}}_3})\}$

What wherein have subscript " Λ " is the estimated value of respective measurement values or physical quantity, L ₁, L ₂, L ₃, λ ₁, λ ₂Be constant, they can regulate and confirm according to demand.In addition, sign is-symbol function defines as follows:

$\mathrm{sign}\left(y\right)=\left\{\begin{array}{cc}-1:& y<0\\ 0:& y=0\\ 1& y>0\end{array}\right\}$

In this way; Unite definite device (more specifically; Definite device based on model) in fact can be regarded as the Adaptive Observer of catalyst converter ammonia storage capacity and ammonia surface concentration; It is through "black box" pattern operation, thereby confirms the ammonia storage capacity of catalyst converter and the estimated value of ammonia surface coverage (and other measure, for example estimated value of working condition measuring value) based on the measured value of catalyst converter operating mode.Fig. 3 schematically shows the structured flowchart based on definite device of model.

Should be noted that the above-described measured value that only is based on the catalyst converter operating mode and confirm the ammonia storage capacity of catalyst converter and the possible example of ammonia surface coverage.Based on instruction and the enlightenment that the utility model provides, those skilled in the art can easily expect the embodiment that any other is feasible.Therefore, anyly when confirming the estimated value of catalyst converter ammonia surface coverage, consider of the distortion of ammonia storage capacity, all fall within the scope of the utility model as variable.

Should be appreciated that shown in Fig. 1 and Fig. 2 and at above-described equipment 100 and 200 to utilize multiple mode to implement.For example, in some embodiments, equipment 100 and 200 can be implemented as intergrated circuit (IC), ASIC (ASIC), SOC(system on a chip) (SOC) or its combination in any.

Below with reference to figure 4, it shows the operation of equipment flow chart that uses in the SCR system of being used for according to the utility model illustrative embodiments.For simplicity, the represented process of this flow chart is designated as method 400.

After method 400 beginnings,, obtain the measured value of at least one operating mode of the catalyst converter in the SCR system at step S402.In some embodiments, the measured value that obtains at least one operating mode of catalyst converter comprise obtain following at least one: the nitrous oxides concentration in the said catalyst converter, the ammonia concentration in the said catalyst converter; And the temperature in the said catalyst converter.

Next, method 400 proceeds to step S404, confirms that based on the said measured value that obtains the ammonia storage capacity of said catalyst converter is so that confirm the ammonia surface coverage of said catalyst converter at this.In some mode of execution of the utility model; Confirming the ammonia storage capacity of said catalyst converter based on the said measured value that obtains comprises so that confirm the ammonia surface coverage of said catalyst converter: based on the said measured value that obtains, confirm the ammonia surface coverage of said catalyst converter together in company with the ammonia storage capacity of said catalyst converter.Alternatively; Confirm that in company with the ammonia storage capacity of said catalyst converter the ammonia surface coverage of said catalyst converter comprises based on the said measured value that obtains together: with said measured value as independent variable; Through using the reaction model of the chemical reaction characteristic that characterizes said catalyst converter, confirm the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter.

In mode of execution, confirm that through the reaction model that uses the chemical reaction characteristic that characterizes said catalyst converter the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter comprise as independent variable: the Observed value of calculating said at least one operating mode according to the said measured value that obtains with said measured value based on reaction model; And, use said measured value and said Observed value to confirm that the ammonia storage capacity of said catalyst converter is so that confirm the ammonia surface coverage of said catalyst converter based on said reaction model.

Method 400 finishes after step S404.

The step that should be appreciated that record in the method 400 corresponds respectively to operation and/or the function of preceding text with reference to each device in the equipment 100 and 200 of figure 1 and Fig. 2 description.Thus, preceding text reference device 100 and each device of 200 and the characteristic described is equally applicable to each step of method 400.And each step of record can be carried out and/or executed in parallel according to different orders in the method 400.

Preceding text have combined some embodiments to explain the spirit and the principle of the utility model.Mode of execution according to the utility model; When confirming based on the operating mode of the catalyst converter that measures or claiming to estimate the ammonia surface coverage of catalyst converter; The ammonia storage capacity of catalyst converter (or claim storage ammonia ability) can be not for another example in the existing technology that kind be assumed that constant all the time, or confirm based on specific dynamics.On the contrary, the mode of execution of the utility model is not done any hypothesis to the dynamics of ammonia storage capacity, and it can be that constant also can be a variable.Especially, can confirm the ammonia storage volume and the ammonia surface coverage of catalyst converter simultaneously based on the Chemical Reaction Model of catalyst converter.The physical features that ammonia storage volume of confirming in this way and ammonia surface coverage can reflect the SCR catalyst converter more truly, exactly.In addition, the solution of the utility model proposition is easy to realize and operation in practice.

The mode of execution that should be noted that the utility model can be through hardware mode realization completely.Hardware components can utilize special logic to realize.Equipment of the utility model and module thereof can by such as vlsi circuit or gate array, such as the semiconductor of logic chip, transistor etc., or realize such as the hardware circuit of the programmable hardware device of field programmable gate array, programmable logic device etc.

Although should be noted that the some devices or the sub-device of the equipment of in above-detailed, having mentioned, this division only is not enforceable.In fact, according to the mode of execution of the utility model, the characteristic of above-described two or more devices and function can be specialized in a device.Otherwise the characteristic of an above-described device and function can further be divided into by multiple arrangement to be specialized.

In addition; Although described the operation of equipment process of the utility model in the accompanying drawings with particular order; But this is not that requirement or hint must be carried out these operations according to this particular order, or the operation shown in must carrying out all could realize the result of expectation.On the contrary, the step of describing in the flow chart can change execution sequence.Additionally or alternatively, can omit some step, a plurality of steps merged into a step carry out, and/or a step is decomposed into a plurality of steps carries out.

Though described the utility model, should be appreciated that the utility model is not limited to disclosed embodiment with reference to some embodiments.The utility model is intended to contain included various modifications and equivalent arrangements in spirit and the scope of accompanying claims.The scope of accompanying claims meets the most wide in range explanation, thereby comprises all such modifications and equivalent structure and function.

Claims (5)

1. equipment that is used for the toxic emission reprocessing of DENG; Said equipment uses in the SCR SCR of DENG system; Said SCR system comprises that catalyst converter transforms the nitrogen oxide of said diesel engine emissions to utilize ammonia, is characterized in that said equipment comprises:

Obtaining device, it is coupled to said catalyst converter, and configuration is used to obtain the measured value of at least one operating mode of said catalyst converter; And

Confirm device, it is coupled to said obtaining device, and configuration is used for the said measured value that obtains based on said obtaining device, confirms that the ammonia storage capacity of said catalyst converter is so that confirm the ammonia surface coverage of said catalyst converter.

2. equipment according to claim 1 is characterized in that said definite device comprises:

Unite definite device, configuration is used for the said measured value that obtains based on said obtaining device, confirms the ammonia surface coverage of said catalyst converter together in company with the ammonia storage capacity of said catalyst converter.

3. equipment according to claim 2 is characterized in that said the associating confirming that device comprises:

Based on definite device of model, configuration is used for said measured value as independent variable, based on the reaction model of the chemical reaction characteristic that characterizes said catalyst converter, confirms the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter.

4. equipment according to claim 3 is characterized in that said definite device based on model comprises:

Computing device, configuration is used for the said measured value that obtains according to said obtaining device, calculates the Observed value of said at least one operating mode;

First confirms device, and configuration is used for based on said reaction model, uses said measured value and said Observed value to confirm the ammonia storage capacity of said catalyst converter and the ammonia surface coverage of said catalyst converter.

5. equipment according to claim 1, it is characterized in that said obtaining device comprise following at least one:

The first concentration obtaining device, configuration is used for obtaining the nitrous oxides concentration of said catalyst converter;

The second concentration obtaining device, configuration is used for obtaining the ammonia concentration of said catalyst converter; And

The temperature obtaining device, configuration is used for obtaining the temperature of said catalyst converter.

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