KR100999622B1 - System for control urea injection of vehicle and method thereof - Google Patents

System for control urea injection of vehicle and method thereof Download PDF

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KR100999622B1
KR100999622B1 KR1020080068304A KR20080068304A KR100999622B1 KR 100999622 B1 KR100999622 B1 KR 100999622B1 KR 1020080068304 A KR1020080068304 A KR 1020080068304A KR 20080068304 A KR20080068304 A KR 20080068304A KR 100999622 B1 KR100999622 B1 KR 100999622B1
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scr catalyst
nox
amount
scr
urea
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KR20100007602A (en
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조지호
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기아자동차주식회사
현대자동차주식회사
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2066—Selective catalytic reduction [SCR]
    • F01N3/208—Control of selective catalytic reduction [SCR], e.g. dosing of reducing agent
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/02—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/14—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics having more than one sensor of one kind
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/02—Adding substances to exhaust gases the substance being ammonia or urea
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/14—Arrangements for the supply of substances, e.g. conduits
    • F01N2610/1453—Sprayers or atomisers; Arrangement thereof in the exhaust apparatus
    • F01N2610/146—Control thereof, e.g. control of injectors or injection valves
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Gas After Treatment (AREA)

Abstract

본 발명은 수치해석 및 반응속도론을 접목한 SCR 반응모델을 적용하여 운전 상황에 따라 우레아 수용액의 분사를 제어하는 것으로,The present invention is to control the injection of the urea aqueous solution according to the operating situation by applying the SCR reaction model that combines numerical analysis and reaction kinetics,

운전조건과 SCR촉매의 온도 및 NOx 정화효율을 검출하는 과정, SCR 반응모델을 적용하여 운전조건과 NOx 정화효율에 따른 NH3 흡착량을 산출하는 과정, NH3의 흡착량에 따른 우레아 수용액의 양을 결정하여 도징모듈의 작동을 통해 SCR 촉매의 전단에 분사하는 과정을 포함한다.Process of detecting operating conditions, temperature and NOx purification efficiency of SCR catalyst, calculating NH3 adsorption amount according to operating conditions and NOx purification efficiency by applying SCR reaction model, and determining the amount of urea solution according to NH3 adsorption amount By spraying the front end of the SCR catalyst through the operation of the dosing module.

SCR촉매, 우레아 수용액, NH3, 도징모듈 SCR catalyst, urea solution, NH3, dosing module

Description

차량의 우레아 분사 제어장치 및 방법{SYSTEM FOR CONTROL UREA INJECTION OF VEHICLE AND METHOD THEREOF}Urea injection control device and method of vehicle {SYSTEM FOR CONTROL UREA INJECTION OF VEHICLE AND METHOD THEREOF}

본 발명은 차량의 촉매 제어장치에 관한 것으로, 더 상세하게는 수치해석 및 반응속도론을 접목한 SCR(Selective Catalytic Reduction) 반응모델을 적용하여 운전 상황에 따라 우레아(Urea) 수용액의 분사를 제어하는 차량의 우레아 분사 제어장치 및 방법에 관한 것이다.The present invention relates to a catalyst control device for a vehicle, and more particularly, a vehicle for controlling injection of urea solution according to driving conditions by applying a SCR (Selective Catalytic Reduction) reaction model incorporating numerical analysis and reaction kinetics. Urea injection control apparatus and method.

디젤 엔진이 적용되는 차량은 북미디젤 Tier2 BIN5 규제나 유로 6의 배기가스 규제에 따라 배기가스에 포함된 NOx, CO, THC, 그을음(soot), 입자상 물질(Particulate Matters) 등의 유해물질을 제거시키는 후처리 장치가 장착된다.Vehicles with diesel engines can remove harmful substances such as NOx, CO, THC, soot and Particulate Matters contained in the exhaust according to North American diesel Tier 2 BIN5 regulation or Euro 6 emission regulations. The aftertreatment device is mounted.

디젤 차량에 장착되는 후처리 장치는 배기 파이프에서 엔진과 가장 근접하게 배치되어 NMHC 변환기능을 실행하는 DOC(Diesel Oxidation Catalyst), DOC의 하류측에 배치되어 입자상 물질(Particulate Matters :PM)을 포집하는 CPF(Catalyzed Particulate Filter), CPF의 하류측에 배치되며 V2O5/TiO2나 Pt/Al2O3 또는 Zeolite로 이루어지며, 환원작용을 통해 NOx를 정화하는 SCR촉매가 포함된다.The post-treatment unit mounted on the diesel vehicle is a DOC (Diesel Oxidation Catalyst) which is disposed closest to the engine in the exhaust pipe and performs NMHC conversion, and collects particulate matter (PM) downstream of the DOC. Catalyzed Particulate Filter (CPF), located downstream of CPF, consists of V 2 O 5 / TiO 2 , Pt / Al 2 O 3 or Zeolite, and includes SCR catalyst to purify NOx through reduction.

상기의 SCR촉매는 NOx를 정화하기 위한 환원제로 NH3(암모니아)를 사용하며, NOx에 대한 선택도가 매우 우수할 뿐만 아니라 산소가 존재하는 경우에도 NOx와 NH3 사이의 반응이 촉진되는 장점이 있다.The SCR catalyst uses NH3 (ammonia) as a reducing agent for purifying NOx, and has an advantage in that the reaction between NOx and NH3 is promoted even in the presence of oxygen as well as excellent selectivity to NOx.

NOx와 NH3의 환원반응은 다음과 같다.The reduction reaction of NOx and NH3 is as follows.

NOx + NH3 → N2 + H2ONOx + NH3 → N2 + H2O

SCR촉매의 NOx 정화성능을 일정수준으로 이상으로 유지하기 위해 도징모듈(Dosing Module)로 우레아(Urea) 수용액을 분사하고, 우레아 수용액의 증발 및 분해에 따라 생성되는 NH3를 취득하여 SCR촉매의 내부에 NH3의 흡착량을 유지시킨다.In order to maintain the NOx purification performance of the SCR catalyst to a certain level or more, the urea solution is sprayed with a dosing module, NH3 generated by the evaporation and decomposition of the urea solution is acquired, and the inside of the SCR catalyst is obtained. The adsorption amount of NH 3 is maintained.

통상적으로 우레아 수용액의 주입량을 증가시키게 되면 NOx 정화율도 증가하는 경향을 보이나, 일정량 이상의 우레아 수용액을 주입하게 되면 생성된 NH3가 분해되지 않거나 반응하지 않고 남게 되어 대기중으로 배출되어 더 심각한 환경오염을 유발시키게 되는 문제점이 발생한다.In general, increasing the injection amount of the urea solution tends to increase the NOx purification rate, but injecting more than a certain amount of urea solution does not decompose or remain without reacting, resulting in more serious environmental pollution. Problem occurs.

특히, 과도한 NH3의 생성으로 인하여 배기관을 통해 배출되는 경우 악취를 유발시키게 되어 차량의 품질을 저하시키는 문제점을 발생시킨다.In particular, when the exhaust gas is discharged through the exhaust pipe due to excessive generation of NH 3, it causes a bad smell, which causes a problem of degrading the quality of the vehicle.

따라서 우레아 수용액의 주입량을 적정하게 유지시키면서 NOx의 정화율을 높이는 것이 매우 중요하다.Therefore, it is very important to increase the NOx purification rate while maintaining an appropriate injection amount of the urea solution.

현재 차량에는 엔진 회전수와 배출가스의 온도로부터 배기가스에 포함되는 NOx 량을 산출한 다음 우레아 수용액의 주입량을 결정하여 분사하는 방식이 제공되고 있다.At present, the vehicle is provided with a method of calculating the amount of NOx contained in the exhaust gas from the engine speed and the temperature of the exhaust gas, and then determining the injection amount of the aqueous urea solution and spraying the same.

이 방식은 운전자의 가감속에 따라 수시로 변화하는 부하에 대하여 NOx 양을 능동적으로 계산할 수 없으며 이에 따라 우레아 분사량 제어가 불확실하게 수행되어지는 단점이 있다.This method can not actively calculate the amount of NOx for the load that changes frequently depending on the acceleration and deceleration of the driver, there is a disadvantage that the urea injection amount control is carried out uncertainly.

NOx 맵에 따라 우레아 수용액을 분사하는 경우 실제 차량에서의 발생량을 예측하는 것이 아니라 대상 엔진에서의 발생량을 기준으로 예측분사하기 때문에 실제의 NOx 발생량과 차이가 불가피하고, 정확한 우레아 수용액의 분사량으로 분사할 수 없으며, SCR촉매의 효율에 대한 정확도가 보장되지 않고, NH3 소모량의 오예측을 유발시키는 문제점이 발생된다.When injecting urea solution according to NOx map, it is not predicted the amount generated in the actual vehicle but is predicted based on the amount generated in the target engine, so it is inevitable to be different from the actual amount of generated NOx. And the accuracy of the efficiency of the SCR catalyst is not guaranteed and causes a problem of causing misprediction of NH3 consumption.

이러한 문제는 필요 이상의 과도한 우레아 수용액이 분사되어 반응되지 못하고 잔류하는 NH3의 배출이라는 2차 오염을 발생시킬 수 있으며, 이를 방지하기 위한 2차, 3차 촉매를 사용하여야 하는 또 하나의 문제점을 발생시킨다.This problem can cause secondary pollution such as the release of excess NH3 solution, which is impossible to react due to excessive injection of urea solution, and another problem of using secondary and tertiary catalysts to prevent this. .

반대로 우레아 수용액의 분사량이 모자라는 경우에는 NOx 정화효율의 저하로 연결되어 배출가스의 안정화를 제공하지 못하는 문제점을 발생시킨다.On the contrary, when the injection amount of the urea aqueous solution is insufficient, it leads to a decrease in NOx purification efficiency, which causes a problem in that it does not provide stabilization of the exhaust gas.

본 발명은 상기한 문제점을 해결하기 위하여 발명한 것으로, 그 목적은 SCR 촉매에서 NOx의 정화에 필요한 NH3를 생성하는데 요구되는 우레아 수용액의 분사량을 수치해석 및 반응속도론이 접목된 SCR 반응모델을 적용하여 결정함으로써, 운전조건에 적합한 최대의 NOx 정화효율이 제공되는 우레아 수용액의 분사가 제공되도록 하는 것이다.The present invention has been invented to solve the above problems, the object of which is to apply the SCR reaction model combined with numerical analysis and reaction kinetics of the injection amount of the aqueous urea solution required to generate NH3 required for the purification of NOx in the SCR catalyst By determining, the injection of an aqueous urea solution is provided which provides the maximum NOx purification efficiency suitable for the operating conditions.

상기한 목적을 실현하기 위한 본 발명의 특징에 따른 차량의 우레아 분사 제어장치는, 엔진; 배기가스에 포함된 NOx와 NH3의 환원반응을 NOx를 정화하는 SCR촉매; 상기 SCR촉매의 양단간 NOx 농도를 검출하는 제1,2NOx센서; 상기 SCR촉매의 선단에 우레아 수용액을 분사하는 도징모듈; 상기 SCR촉매의 온도를 검출하는 온도센서를 포함하며,An urea injection control apparatus for a vehicle according to a feature of the present invention for realizing the above object includes an engine; SCR catalyst for purifying NOx by the reduction reaction of NOx and NH3 contained in the exhaust gas; First and second NOx sensors detecting NOx concentration between both ends of the SCR catalyst; A dosing module for injecting an aqueous urea solution at the tip of the SCR catalyst; It includes a temperature sensor for detecting the temperature of the SCR catalyst,

운전조건과 SCR촉매의 NOx 정화효율에 따라 SCR 반응모델을 통해 SCR촉매의 필요 NH3 양을 산출하고, 우레아 수용액의 양을 결정하여 도징모듈을 통해 분사 제어하는 제어부를 더 포함한다.According to the operating conditions and the NOx purification efficiency of the SCR catalyst further comprises a control unit for calculating the required NH3 amount of the SCR catalyst through the SCR reaction model, determining the amount of the urea aqueous solution and injection control through the dosing module.

또한, 본 발명의 특징에 따른 차량의 우레아 분사 제어방법은, 운전조건과 SCR촉매의 온도 및 NOx 정화효율을 검출하는 과정; SCR 반응모델을 적용하여 운전조건과 NOx 정화효율에 따른 NH3 흡착량을 산출하는 과정; NH3의 흡착량에 따른 우레아 수용액의 양을 결정하여 도징모듈의 작동을 통해 SCR 촉매의 전단에 분사하는 과정을 포함한다.In addition, the urea injection control method of the vehicle according to the characteristics of the present invention, the process of detecting the operating conditions and the temperature and NOx purification efficiency of the SCR catalyst; Calculating NH3 adsorption amount according to operating conditions and NOx purification efficiency by applying SCR reaction model; Determining the amount of the urea aqueous solution according to the adsorption amount of NH3 and spraying the front end of the SCR catalyst through the operation of the dosing module.

전술한 구성에 의하여 본 발명은 SCR 촉매에서 NH3의 생성에 필요한 양의 우레아 수용액을 결정하여 분사함으로써, 우레아 수용액의 소모를 최소화하면서도 NOx의 정화효율이 최대화되는 효과가 기대된다.According to the above-described configuration, the present invention is expected to minimize the consumption of the urea solution while maximizing the NOx purification efficiency by determining and spraying the urea solution of the amount required for the production of NH 3 in the SCR catalyst.

또한, 우레아 수용액이 엔진 조건에 맞는 현실적인 분사량으로 제어됨으로써, NH3의 과다 혹은 과소 생성으로 인한 배기가스 불안정이 발생되지 않는다.In addition, since the urea aqueous solution is controlled to a realistic injection amount suitable for the engine conditions, exhaust gas instability due to excessive or underproduction of NH 3 is not generated.

아래에서는 첨부한 도면을 참고로 하여 본 발명의 실시예에 대하여 본 발명이 속하는 기술 분야에서 통상의 지식을 가진 자가 용이하게 실시할 수 있도록 상세히 설명한다. DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

본 발명은 여러 가지 상이한 형태로 구현될 수 있으므로, 여기에서 설명하는 실시예에 한정되지 않으며, 도면에서 본 발명을 명확하게 설명하기 위해서 설명과 관계없는 부분은 생략하였다.Since the present invention can be implemented in various different forms, the present invention is not limited to the exemplary embodiments described herein, and parts not related to the description are omitted in the drawings in order to clearly describe the present invention.

도 1은 본 발명의 실시예에 따른 차량의 우레아 분사 제어장치를 개략적으로 도시한 도면이다.1 is a view schematically showing a urea injection control apparatus for a vehicle according to an embodiment of the present invention.

본 발명은 동력원인 엔진(2), 연소된 배기가스를 배출시키는 배기 파이프(6), SCR촉매(10), 제1NOx센서(12), 제2NOx센서(14), 온도센서(16), 제어부(18), 도징모듈(20), 우레아 탱크(30) 및 펌프(32)를 포함한다.The present invention is an engine (2) as a power source, an exhaust pipe (6) for discharging burned exhaust gas, an SCR catalyst (10), a first NOx sensor (12), a second NOx sensor (14), a temperature sensor (16), a controller 18, the dosing module 20, the urea tank 30 and the pump 32.

상기 SCR촉매(10)는 엔진(2)과 연결되는 배기 파이프(6)의 소정 위치에 배치되어 V2O5/TiO2 또는 Pt/Al2O3 또는 Zeolite로 이루어지며, 우레아 수용액의 분해로 산출되는 NH3와 NOx의 환원반응에 의해 NOx를 정화한다.The SCR catalyst 10 is disposed at a predetermined position of the exhaust pipe 6 connected to the engine 2 and is composed of V 2 O 5 / TiO 2 or Pt / Al 2 O 3 or Zeolite, The NOx is purified by the reduction reaction of NH3 and NOx produced.

제1NOx센서(12)는 SCR촉매(10)의 입구측에 배치되어 SCR촉매(10)에 유입되는 배기가스에 포함된 NOx 양을 검출하여 그에 대한 정보를 제어부(18)에 제공한다.The first NOx sensor 12 is disposed at the inlet side of the SCR catalyst 10 to detect the amount of NOx contained in the exhaust gas flowing into the SCR catalyst 10 and provide information to the controller 18.

제2NOx센서(14)는 SCR촉매(10)의 출구측에 배치되어 SCR촉매(10)의 환원반응에 의해 정화된 배기가스에 포함된 NOx 양의 검출하여 그에 대한 정보를 제어 부(18)에 제공한다.The second NOx sensor 14 is disposed at the outlet side of the SCR catalyst 10 and detects the amount of NOx contained in the exhaust gas purified by the reduction reaction of the SCR catalyst 10 and transmits information on the information to the control unit 18. to provide.

온도센서(16)는 배기가스의 온도에 의해 활성화되는 SCR촉매(10)의 온도를 검출하여 그에 대한 정보를 제어부(18)에 제공한다.The temperature sensor 16 detects the temperature of the SCR catalyst 10 activated by the temperature of the exhaust gas and provides information about the SCR catalyst 10 to the controller 18.

제어부(18)는 공기량과 엔진 회전수의 정보, 배기가스 온도를 분석하여 엔진의 운전조건을 분석하고, 제1,2NOx센서(12)(14)의 정보와 온도센서(16)의 정보를 분석하여 온도에 따른 SCR촉매(10)의 NOx 정화효율을 분석하며, 운전조건과 NOx 정화효율에 따라 수치해석과 반응속도론을 접목한 SCR 반응모델을 적용하여 SCR촉매(10)의 필요 NH3 양을 산출한다.The controller 18 analyzes the operating conditions of the engine by analyzing the information of the air volume, the engine speed, and the exhaust gas temperature, and analyzes the information of the first and second NOx sensors 12 and 14 and the information of the temperature sensor 16. Analyze the NOx purification efficiency of the SCR catalyst 10 according to the temperature and calculate the required NH3 amount of the SCR catalyst 10 by applying the SCR reaction model that combines numerical analysis and reaction kinetics according to the operating conditions and NOx purification efficiency. do.

그리고, 필요 NH3의 양에 따라 요구되는 우레아 수용액의 양을 결정하여 도징모듈(20)을 통해 우레아 수용액의 분사를 제어한다.Then, the amount of the required urea solution is determined according to the amount of NH 3 required to control the injection of the urea solution through the dosing module 20.

상기 제어부(18)는 PWM(Pulse Width Modulation) 신호의 출력으로 도징모듈(20)의 작동시켜 우레아 수용액의 분사를 제어한다.The control unit 18 controls the injection of the urea solution by operating the dosing module 20 by outputting a pulse width modulation (PWM) signal.

우레아 탱크(30)는 운전조건에 따라 SCR촉매(10)의 선단에 분사하기 위한 우레아 수용액이 수용되고, 펌프(32)는 우레아 탱크(30)로부터 도징도뮬(20)에 공급되는 우레아 수용액을 설정된 압력으로 형성시켜 PWM신호에 따라 도징모듈(20)이 작동되는 경우 고압의 분사가 제공되도록 한다.The urea tank 30 accommodates an aqueous urea solution for injecting to the tip of the SCR catalyst 10 according to the operating conditions, and the pump 32 receives the urea solution supplied from the urea tank 30 to the dosing dome 20. It is formed at a set pressure so that the injection of high pressure is provided when the dosing module 20 is operated according to the PWM signal.

전술한 기능을 포함하는 본 발명에 따른 차량에서 우레아 수용액의 분사를 제어하는 동작에 대하여 설명한다.An operation of controlling the injection of the urea aqueous solution in the vehicle according to the present invention including the above-described function will be described.

엔진(2)이 시동 온되면 제어부(18)는 공기량, 엔진 회전수, 부하 등의 정보를 종합하여 엔진(2)의 동작을 제어하며(S101), 온도센서(16)를 통해 SCR촉매(10) 의 온도를 검출하여 SCR촉매(10)의 활성화가 이루어졌는지를 판단한다(S102).When the engine 2 is started on, the controller 18 controls the operation of the engine 2 by synthesizing information such as air volume, engine speed, and load (S101), and the SCR catalyst 10 through the temperature sensor 16. It is determined whether the activation of the SCR catalyst 10 by detecting the temperature of the (S102).

상기 SCR촉매(10)의 활성화가 이루어진 상태이면 SCR촉매(10) 전후단의 NOx 농도를 검출한다(S103).When the SCR catalyst 10 is activated, NOx concentrations of the front and rear ends of the SCR catalyst 10 are detected (S103).

즉, SCR촉매(10)의 입구측에 배치되는 제1NOx센서(12)와 출구측에 배치되는 제2NOx센서(14)의 정보를 분석하여 SCR촉매(10)의 NOx 정화효율을 판단한다. That is, the NOx purification efficiency of the SCR catalyst 10 is determined by analyzing the information of the first NOx sensor 12 disposed on the inlet side of the SCR catalyst 10 and the second NOx sensor 14 disposed on the outlet side.

상기 SCR촉매(10)의 반응 모델링은 다음과 같다.Reaction modeling of the SCR catalyst 10 is as follows.

우레아 수용액의 분해에 따른 NH3의 흡착은 화학식 1과 같이 반응된다.Adsorption of NH3 upon decomposition of aqueous urea solution is reacted as in Chemical Formula 1.

NH3 + SACID → SACIDNH3NH3 + S ACID → S ACID NH3

그리고, NH3와 NOx의 반응은 화학식 2와 같다.And, the reaction of NH3 and NOx is the same as the formula (2).

NO + NO2 + 2SACIDNH3 → 2N2 + 3H2ONO + NO 2 + 2S ACID NH 3 → 2N 2 + 3H 2 O

4NO + O2 + 4SACIDNH3 → 4N2 + 6H2O4NO + O 2 + 4S ACID NH 3 → 4N 2 + 6H 2 O

6NO2 + 8SACIDNH3 → 7N2 + 12H2O6NO 2 + 8S ACID NH 3 → 7N 2 + 12H 2 O

또한, SCR촉매(10)내에서 NH3의 탈착은 화학식 3과 같이 반응된다.In addition, desorption of NH 3 in the SCR catalyst 10 is reacted as in Chemical Formula 3.

SACIDNH3 → NH3 + SACID S ACID NH3 → NH3 + S ACID

이후, 수치해석과 반응속도론을 접목한 SCR 반응모델을 적용한 다음(S104) 상기 현재의 운전조건에서 판단되는 SCR촉매(10)의 NOx 정화효율에 따라 NH3의 흡착량을 예측한다(S105)Subsequently, the SCR reaction model combining the numerical analysis and the reaction kinetics is applied (S104), and then the amount of NH3 adsorption is predicted according to the NOx purification efficiency of the SCR catalyst 10 determined under the current operating conditions (S105).

상기에서 NH3의 흡착량 예측은 SCR촉매(10)의 온도별, 배기유량별, NOx 농도별, NH3 농도별 조건에 따라 결정되며, SCR촉매(10)의 NH3 흡착과 탈착 관계는 도 3에 도시된 바와 같다.The NH3 adsorption amount prediction is determined according to the temperature, exhaust flow rate, NOx concentration, and NH3 concentration conditions of the SCR catalyst 10, and the relationship between NH3 adsorption and desorption of the SCR catalyst 10 is shown in FIG. As it is.

상기 S105에서 현재의 운전조건에 따른 SCR촉매(10)의 실질적인 NH3 흡착량이 예측되면 이에 따라 요구되는 우레아 수용액의 양을 결정한다(S106)In step S105, if the actual NH3 adsorption amount of the SCR catalyst 10 according to the current operating conditions is predicted, the amount of the required urea solution is determined accordingly (S106).

상기 SCR촉매(10)의 선단에 분사하기 위한 우레아 수용액의 양은 우레아 수용액이 NH3로 변환될 수 있는 상수를 적용하여 상기 S105에서 예측된 NH3의 흡착량을 추종하도록 한다.The amount of urea solution to be sprayed to the tip of the SCR catalyst 10 is applied to a constant urea solution can be converted to NH 3 to follow the adsorption amount of NH 3 predicted in S105.

상기와 같이 SCR촉매(10)에서 흡착에 필요한 NH3에 따른 우레아 수용액의 양이 결정되면 제어부(18)는 도징모듈(20)을 PWM신호로 작동시켜 SCR촉매(10)의 선단에 우레아 수용액을 분사한다(S107).As described above, when the amount of urea solution according to NH 3 required for adsorption in the SCR catalyst 10 is determined, the controller 18 operates the dosing module 20 as a PWM signal to inject the urea solution into the tip of the SCR catalyst 10. (S107).

따라서, SCR촉매(10)는 NH3의 슬립이나 부족이 없는 조건으로 NOx와 환원반응하여 NOx의 정화효율을 높여주고, NH3의 슬립으로 인한 2차 오염이 발생되는 현상을 배제하여 차량의 상품성을 향상시킨다.Therefore, the SCR catalyst 10 reduces NOx by reducing reaction with NOx in a condition that there is no slip or lack of NH3, and improves the merchandise of the vehicle by excluding the phenomenon of secondary pollution caused by slip of NH3. Let's do it.

도 2는 SCR촉매(10)의 온도별, 배기유량별, NOx 농도별, NH3 농도별 조건을 하기의 테이블과 같이 설정될 때 NOx의 정화성능 예측값과 실험값의 비교 결과 그래프이다.FIG. 2 is a graph showing a comparison result between NOx purification performance and experimental values when the temperature, exhaust flow rate, NOx concentration, and NH3 concentration conditions of the SCR catalyst 10 are set as shown in the table below.

SCR 촉매온도(℃)SCR catalyst temperature (℃) 배기유량(kg/h)Exhaust flow rate (kg / h) 전단 NOx(ppm)Shear NOx (ppm) NH3/NOxNH3 / NOx 250250 156156 347347 1.181.18 1.501.50 300300 164164 448448 1.121.12 1.501.50 400400 199199 756756 1.101.10

도 4에 도시된 바와 같이 상기한 절차를 통해 결정한 우레아 수용액의 분사에 따른 SCR촉매(10)에 NOx 정화효율은 예측치와 실험치가 동일 내지 유사한 특성을 나타내고 있음을 확인할 수 있다.As shown in FIG. 4, the NOx purification efficiency of the SCR catalyst 10 according to the injection of the urea aqueous solution determined through the above procedure may be confirmed to have the same or similar characteristics as those of the predicted value and the experimental value.

이상에서 본 발명의 실시예에 대하여 상세하게 설명하였지만 본 발명의 권리범위는 이에 한정되는 것은 아니고 다음의 청구범위에서 정의하고 있는 본 발명의 기본 개념을 이용한 당업자의 여러 변형 및 개량 형태 또한 본 발명의 권리범위에 포함된다.Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It is included in the scope of rights.

도 1은 본 발명의 실시예에 따른 차량의 우레아 분사 제어장치를 개략적으로 도시한 도면이다.1 is a view schematically showing a urea injection control apparatus for a vehicle according to an embodiment of the present invention.

도 2는 본 발명의 실시예에 따른 차량에서 우레아 분사제어를 실행하는 흐름도이다.2 is a flowchart for performing urea injection control in a vehicle according to an embodiment of the present invention.

도 3은 본 발명의 실시예에 따른 차량의 SCR촉매에서 NH3의 흡착 및 탈착 관계를 도시한 도면이다.3 is a diagram illustrating the adsorption and desorption relationship of NH 3 in the SCR catalyst of a vehicle according to an embodiment of the present invention.

도 4는 본 발명의 실시예에 따른 차량에서 SCR촉매 온도별 NOx의 정화성능을 도시한 도면이다.4 is a view showing the purification performance of NOx for each SCR catalyst temperature in a vehicle according to an embodiment of the present invention.

<도면의 주요 부분에 대한 부호의 설명><Explanation of symbols for the main parts of the drawings>

2 : 엔진 6 : 배기 파이프2: engine 6: exhaust pipe

10 : SCR촉매 12 : 제1NOx센서10: SCR catalyst 12: 1st NOx sensor

14 : 제2NOx센서 16 : 온도센서14 second NOx sensor 16 temperature sensor

18 : 제어부 20 : 도징모듈 18: control unit 20: dosing module

30 : 요소탱크 32 : 펌프30: element tank 32: pump

Claims (5)

엔진(2); 배기가스에 포함된 NOx와 NH3의 환원반응을 NOx를 정화하는 SCR촉매(10); 상기 SCR촉매(10)의 양단간 NOx 농도를 검출하는 제1,2NOx센서(12,14); 상기 SCR촉매(10)의 선단에 우레아 수용액을 분사하는 도징모듈(20); 상기 SCR촉매(10)의 온도를 검출하는 온도센서(16); 운전조건과 SCR촉매(10)의 NOx 정화효율에 따라 SCR 반응모델을 통해 SCR촉매(10)의 필요 NH3 양을 산출하고, 우레아 수용액의 양을 결정하여 도징모듈(20)을 통해 분사 제어하는 제어부(18)를 포함하는 차량의 우레아 수용액 분사 제어장치에 있어서,Engine 2; SCR catalyst 10 for purifying NOx by the reduction reaction of NOx and NH3 contained in the exhaust gas; First and second NOx sensors 12 and 14 detecting NOx concentrations between both ends of the SCR catalyst 10; A dosing module 20 for spraying an urea aqueous solution at the tip of the SCR catalyst 10; A temperature sensor 16 for detecting the temperature of the SCR catalyst 10; The control unit calculates the required NH3 amount of the SCR catalyst 10 through the SCR reaction model according to the operating conditions and the NOx purification efficiency of the SCR catalyst 10, and determines the amount of the urea aqueous solution and controls the injection through the dosing module 20. A urea solution injection control apparatus for a vehicle comprising 18, 상기 제어부(18)는 공기량과 엔진 회전수 및 배기가스 온도로 결정되는 운전조건과 제1,2NOx센서(12,14)의 정보와 온도센서(16)의 정보로 결정되는 SCR촉매(10)의 NOx정화효율 및 수치해석과 반응속도론이 접목되어 SCR촉매(10)의 온도조건, 배기 유량, NOx 농도, NH3 농도에 따라 테이블로 설정되는 SCR 반응모델을 적용하여 SCR촉매(10)의 필요 NH3 양을 산출하는 것을 특징으로 하는 차량의 우레아 수용액 분사 제어장치.The controller 18 is configured to determine the operating conditions determined by the air volume, engine speed, and exhaust gas temperature, information of the first and second NOx sensors 12 and 14, and information of the temperature sensor 16 of the SCR catalyst 10. Combined with NOx purification efficiency, numerical analysis and reaction kinetics, the required NH3 amount of SCR catalyst (10) is applied by applying SCR reaction model that is set in table according to temperature condition, exhaust flow rate, NOx concentration, and NH3 concentration of SCR catalyst (10). Urea aqueous solution injection control device of the vehicle, characterized in that for calculating. 삭제delete 삭제delete 운전조건과 SCR촉매의 온도 및 NOx 정화효율을 검출하는 과정;Detecting operating conditions and temperature and NOx purification efficiency of the SCR catalyst; SCR 반응모델을 적용하여 운전조건과 NOx 정화효율에 따른 NH3 흡착량을 산출하는 과정;Calculating NH3 adsorption amount according to operating conditions and NOx purification efficiency by applying SCR reaction model; NH3의 흡착량에 따른 우레아 수용액의 양을 결정하여 도징모듈의 작동을 통해 SCR 촉매의 전단에 분사하는 과정;Determining the amount of aqueous urea solution in accordance with the adsorption amount of NH 3 and spraying the front end of the SCR catalyst through the operation of the dosing module; 을 포함하는 차량의 우레아 수용액 분사 제어방법.Urea aqueous solution injection control method of a vehicle comprising a. 제4항에 있어서,The method of claim 4, wherein 상기 NH3 흡착량은 SCR 촉매의 온도, 배기유량, NOx 농도, NH3 농도별 NOx의 환원특성이 적용되어 산출되는 차량의 우레아 수용액 분사 제어방법. The NH3 adsorption amount of the urea aqueous solution injection control method of the vehicle is calculated by applying the reduction characteristics of the temperature, exhaust flow rate, NOx concentration, NH3 concentration of the SCR catalyst.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101316390B1 (en) * 2011-11-22 2013-10-08 현대자동차주식회사 Variable type urea dispersing apparatus
KR101366994B1 (en) * 2012-12-28 2014-02-25 두산엔진주식회사 Power unit with exhaust gas clarifying system and control method thereof
KR101592776B1 (en) 2014-10-21 2016-02-18 현대자동차주식회사 Apparatus and Method for Detecting Manipulated of Exhaust Gas Temperature Sensor of Vehicle
EP3660288B1 (en) * 2017-07-26 2021-06-09 Robert Bosch GmbH Injection amount control method and device for scr urea injection system in engine
KR102529523B1 (en) * 2018-11-27 2023-05-04 현대자동차주식회사 Method for controlling urea supply of exhaust purification apparatus for vehicle

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004068659A (en) 2002-08-05 2004-03-04 Nikki Co Ltd Exhaust emission control device
JP2005127256A (en) * 2003-10-24 2005-05-19 Mitsubishi Fuso Truck & Bus Corp Exhaust emission control device for internal combustion engine
JP2005256633A (en) 2004-03-09 2005-09-22 Hiroshi Matsuoka Exhaust emission control system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004068659A (en) 2002-08-05 2004-03-04 Nikki Co Ltd Exhaust emission control device
JP2005127256A (en) * 2003-10-24 2005-05-19 Mitsubishi Fuso Truck & Bus Corp Exhaust emission control device for internal combustion engine
JP2005256633A (en) 2004-03-09 2005-09-22 Hiroshi Matsuoka Exhaust emission control system

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9181835B2 (en) 2013-08-13 2015-11-10 Caterpillar Inc. Supervisory model predictive selective catalytic reduction control method
KR20150062676A (en) * 2013-11-29 2015-06-08 현대중공업 주식회사 Apparatus and Method for Urea Provision Control in Selective Catalytic Reduction System
KR102017348B1 (en) * 2013-11-29 2019-09-02 한국조선해양 주식회사 Apparatus and Method for Urea Provision Control in Selective Catalytic Reduction System
KR20160092332A (en) 2015-01-27 2016-08-04 세종공업 주식회사 Urea sensor and method for fabricating the same
KR101664702B1 (en) 2015-06-12 2016-10-12 현대자동차주식회사 Control method for UREA injection of SCR system
KR20190134943A (en) * 2018-05-24 2019-12-05 현대자동차주식회사 CORRECTION METHOD OF NOx PURIFYING EFFICIENCY OF SDPF
KR102518593B1 (en) 2018-05-24 2023-04-05 현대자동차 주식회사 CORRECTION METHOD OF NOx PURIFYING EFFICIENCY OF SDPF

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