CN107060989B

CN107060989B - Three stage of the three turbocharger sequential turbocharging device and its control method of function are realized with EGR

Info

Publication number: CN107060989B
Application number: CN201710204422.4A
Authority: CN
Inventors: 王银燕; 李宗营; 宋恩哲; 杨传雷; 王贺春
Original assignee: Harbin Engineering University
Current assignee: Harbin Engineering University
Priority date: 2017-03-31
Filing date: 2017-03-31
Publication date: 2019-05-17
Anticipated expiration: 2037-03-31
Also published as: CN107060989A

Abstract

The purpose of the present invention is to provide three stage of three turbocharger sequential turbocharging devices and its control method that function is realized with EGR, including exhaust header, inlet manifold, No. 1 big turbocharger, No. 2 big turbocharger, small turbocharger, the input end of No. 1 turbine is connected to exhaust header, the input end of No. 2 turbines is connected to exhaust header, the input end of small size turbine is connected to exhaust header, the outlet end of No. 1 turbine, the outlet end of No. 2 turbines, small turbine outlet end be connected to discharge manifold；No. 1 compressor, No. 2 compressors, small compressor input end be connected to inlet manifold, the outlet end of No. 1 compressor is connected to outlet general pipeline, and the outlet end of No. 2 compressors is connected to outlet general pipeline, and the outlet end of small compressor is connected to outlet general pipeline；The present invention, which can play the role of sequential pressurizing, to be improved diesel engine low-load performance and meets diesel engine in the NOx emission requirement in emission control area by EGR, and the comprehensive performance of diesel engine can be greatly improved.

Description

Three stage of the three turbocharger sequential turbocharging device of function is realized with EGR And its control method

Technical field

The present invention relates to a kind of diesel exhaust utilize device and its control method, specifically EGR device and Its control method.

Background technique

Traditional turbocharging technology can greatly improve the mean effective pressure of diesel engine, but can bring simultaneously certain The problem of, when diesel engine operates in low operating condition, exhaust energy is lower, and efficiency of turbocharger and boost pressure, which are substantially reduced, to be caused to supply Tolerance is insufficient, and in-cylinder combustion is bad, and fuel consumption rate increases, and excessive discharge temperature and emission performance deteriorate, if selected increasing Depressor selection is too small, and when diesel engine operates in high operating condition, boost pressure and supercharger speed all can be excessively high, influence diesel engine With the service life of turbocharger, consecutive pressurization system uses two or more turbocharger, with engine with supercharger The growth of revolving speed and load, puts into operation in order in succession, to enable turbo-charged diesel in entire operation range There are higher pressure ratio and preferable economy, meet the air requirements of different operating condition diesel engines, the sequential pressurizing stage is more, cuts Change it is more steady, work it is more stable.In recent years, diesel engine by its thermal efficiency, economy, in terms of advantage by Concern, although the use of diesel engine is greatly promoted the development and progress of society, it also brings along in use The a series of problem such as environmental pollution, wherein NOx is one of main noxious pollutant, and greatly danger can be generated to human body Evil, corresponding emission regulation has been formulated in countries in the world one after another, for marine diesel, in emission control area requirement NOx Being emitted on original basis is reducing by 70%, and EGR technology is that exhaust gas a part of in diesel exhaust gas is introduced into air inlet pipe, It participates in burning again with cylinder is entered after fresh air mixing, reduces air inlet oxygen content and ignition temperature, and then can reduce Diesel NOx discharges and meets emission request.

Summary of the invention

The purpose of the present invention is to provide be able to achieve sequential turbocharging and discharge of the diesel engine in non-emission control area Three stage of the three turbocharger sequential turbocharging that function is realized with EGR of the sequential turbocharging joint EGR of control zone Device and its control method.

The object of the present invention is achieved like this:

Three stage of the three turbocharger sequential turbocharging device that there is the present invention EGR to realize function, it is characterized in that: packet Exhaust header, inlet manifold, No. 1 big turbocharger, No. 2 big turbocharger, small turbocharger are included, No. 1 big turbine increases Depressor includes No. 1 compressor, No. 1 turbine, and No. 2 big turbocharger includes No. 2 compressors, No. 2 turbines, small turbocharger packet Include small compressor, small turbine；The input end of No. 1 turbine is connected to exhaust header by No. 1 exhaust pipe, and the input end of No. 2 turbines is logical Cross No. 2 exhaust pipes connection exhaust headers, the input end of small size turbine passes through small size exhaust pipe and is connected to exhaust header, No. 1 turbine Outlet end, the outlet end of No. 2 turbines, small turbine outlet end be connected to discharge manifold, delivery pipe is connected to atmosphere；No. 1 compressor, No. 2 compressors, small compressor input end be connected to inlet manifold, inlet manifold one end is connected to atmosphere, and the other end is connected to EGR Pipe, EGR pipe are connected to discharge manifold, and the outlet end of No. 1 compressor is connected to outlet general pipeline by No. 1 escape pipe, and No. 2 compressors go out Mouth end is connected to outlet general pipeline by No. 2 escape pipes, and the outlet end of small compressor passes through small size escape pipe connection outlet general pipeline, outlet General pipeline is connected to inlet manifold by air inlet communicating pipe；No. 1 gas valve is installed, No. 2 combustions of installation on No. 2 exhaust pipes on No. 1 exhaust pipe Air valve installs No. 3 gas valves on small size exhaust pipe, No. 1 air cutoff valve is installed on No. 1 escape pipe, installs 2 on No. 2 escape pipes Number air cutoff valve installs EGR valve on small size escape pipe.

The present invention have EGR realize function three stage of three turbocharger sequential turbocharging device can also include:

1, small compressor air control valve is installed on the inlet manifold between No. 2 compressors and small compressor, is pacified in EGR pipe Cooler for recycled exhaust gas, EGR washer, small compressor exhaust gas control valve are filled, air inlet installs aerial cooler on communicating pipe.

Three stage of the three turbocharger sequential turbocharging control method that there is the present invention EGR to realize function, feature It is:

When diesel engine operates in non-emission control area:

Small compressor air control valve is opened, and small compressor exhaust gas control valve is closed, and EGR washer and cooler for recycled exhaust gas are not Participate in work；

(1) when diesel engine is in low operating condition: close No. 1 gas shutoff valve, No. 2 gas shutoff valves, No. 1 air valve and No. 2 air valves open No. 3 gas control valves and standard-sized sheet EGR valve；

(2) when diesel engine operates in medium-heavy duty: opening No. 2 gas valves and No. 2 on the basis of diesel engine low operating condition Air valve makes No. 2 big turbocharger start to devote oneself to work, at this time No. 2 big turbocharger and small turbocharger while work Make；

(3) when diesel engine operates in high operating condition: opened on the basis of diesel engine medium-heavy duty No. 1 air cutoff valve and No. 1 gas shutoff valve, three turbocharger work at the same time at this time.

When diesel engine operates in emission control area:

(a) when diesel engine is in low condition range: closing No. 1 gas shutoff valve, No. 2 gas shutoff valves, No. 1 air Shut-off valve, No. 2 air cutoff valves and small compressor exhaust gas control valve open No. 3 gas control valves, the control of small compressor air Valve and standard-sized sheet EGR valve,；

(b) when diesel engine operates in medium-heavy duty: opening No. 3 gas valves, No. 2 gas valves, No. 2 air valves, small calm the anger Machine exhaust gas control valve, EGR valve simultaneously close off small compressor air control valve, and EGR washer and cooler for recycled exhaust gas are started to work, this When No. 2 big turbocharger and small turbocharger work at the same time, No. 2 compressor inlets connect atmosphere, and small compressor inlet connects Connect exhaust gas washed and after cooling；

(c) when diesel engine operates in high operating condition: opening No. 1 gas shutoff valve, No. 1 air cutoff valve, No. 2 gas valves, 2 Number air valve, No. 3 gas valves, small compressor exhaust gas control valve, EGR valve, simultaneously close off small compressor air control valve, EGR is washed It washs device and cooler for recycled exhaust gas is started to work, three turbocharger work at the same time at this time, No. 1 compressor, No. 2 compressor inlet connections Atmosphere, small compressor inlet connect washed and after cooling exhaust gas.

Present invention has an advantage that the present invention can be realized by two big turbocharger and one small turbocharger Diesel engine non-emission control region three stage adjustable consecutives be pressurized, solve diesel engine in low operating condition due to exhaust energy not Foot, turbocharger are sluggish serious, and cylinder intake air quantity caused by turbine efficiency is lower is insufficient, and burning deteriorates, fuel consumption rate compared with The problems such as high, for three stage sequential turbochargings are with respect to two stages sequential turbocharging, works more stable, transition effect is more Ideal can take into account overall performance.Simultaneously EGR can also be realized on the basis of three stage sequential pressurizings in emission control area, The oxygen content and maximum combustion temperature of air inlet are reduced, and then reduces the NOx emission of diesel engine, to meet emission control area Emission request, small size turbocharger air compressor compression is not air but the exhaust gas after turbine at this time, does not need additionally to borrow It helps EGR blower that can overcome the pressure difference between diesel engine intake and exhaust, improves Diesel Engine Complete Machine efficiency, the EGR rate of diesel engine It is that adjustable range is larger to may be implemented diesel engine difference work by being adjusted by the EGR valve after small turbocharger air compressor The Optimum EGR rate of condition.

Detailed description of the invention

Fig. 1 is the structural diagram of the present invention；

Fig. 2 is flow chart of the invention.

Specific embodiment

It illustrates with reference to the accompanying drawing and the present invention is described in more detail:

In conjunction with Fig. 1-2, three stage of the three turbocharger sequential turbocharging disclosed by the invention that function is realized with EGR Device specifically includes that exhaust header 1, inlet manifold 2,5, No. 2 gas valves 6 of the gas valve of gas valve 4,1 of diesel engine 3,3, small Turbocharger air compressor exhaust gas control valve 7, EGR washer 8, cooler for recycled exhaust gas 9, the control of small turbocharger air compressor air 11, No. 1 big turbocharger turbine 12, the 2 big turbocharger air compressors 13,2 of valve 10,1 big turbocharger air compressors Number big turbocharger turbine 14, small turbocharger air compressor 15,16, No. 1 air cutoff valves 17 of small turbocharger turbine, No. 2 air cutoff valves 18, EGR valve 19, aerial cooler 20 and it is relatively large in diameter exhaust pipe 21.Each cylinder of diesel engine leads to respectively Exhaust branch pipe connection exhaust header 1 is crossed, inlet manifold 2 is connected by air intake branch；Exhaust gas difference after 1 pressure stabilizing of exhaust header Lead to No. 1 big turbocharger, No. 2 big turbines by No. 1 gas shutoff valve 4 of gas shutoff valve 6,3 of gas shutoff valve 5,2 The entrance of booster and small turbocharger turbine 12,14,16, the exhaust gas come out from turbocharger turbine 12,14,16 are logical Cross a 21 directly row Xiang great Qi being relatively large in diameter；No. 1 big turbocharger air compressor 11 and No. 2 big turbocharger are calmed the anger 13 entrance of machine is directly connected to atmosphere, and small size 15 entrance of turbocharger air compressor can both be directly connected to atmosphere or can connect useless The exhaust gas of air pipe end, wherein they are calmed the anger by small turbocharger air compressor air shut-off valve 10 and small turbocharger Machine exhaust gas control valve 7 controls, and is equipped with small turbocharger on the pipeline of small 15 entrance of turbocharger air compressor connection atmosphere Compressor air control valve 10 is installed on the EGR line between 21 end of small turbocharger air compressor entrance and exhaust pipe There are small turbocharger air compressor exhaust gas control valve 7, EGR washer 8 and cooler for recycled exhaust gas 9；No. 1 big turbocharger, No. 2 The blower outlet of big turbocharger pressure and small turbocharger passes through 17, No. 2 air cutoff valves of No. 1 air cutoff valve respectively 18 and EGR valve 19 connect 20 entrance of aerial cooler, and from aerial cooler 20 come out fresh air be directly communicated to air inlet Collector 3 participates in burning into cylinder, and the EGR rate of diesel engine difference operating condition is to adjust the aperture of EGR valve 19 by closed loop to realize 's.

The specific control program of the device is as follows:

When diesel engine operates in non-emission control area

Small turbocharger air compressor air shut-off valve 10 is opened, and small turbocharger air compressor exhaust gas control valve 7 is closed, EGR washer 8 and cooler for recycled exhaust gas 9 are not involved in work, and diesel engine is in pure phase after boost mode at this time.

(1) when diesel engine is in low operating condition: closing No. 1 air valve 17 of gas shutoff valve 6,1 of gas shutoff valve 5,2 And No. 2 air valves 18, No. 3 gas control valves 4 and standard-sized sheet EGR valve 19 are opened, at this time only small turbocharger operation, turbine Circulation area is smaller, and response is fast, and turbine efficiency is high, and acting ability is strong, can generate higher pressure ratio and flow, improve low operating condition Acceleration and load response characteristic.

(2) when diesel engine operates in medium-heavy duty: No. 2 gas valve 6 and No. 2 air valves 18 are opened on the basis of (1), No. 2 big turbocharger is set to start to devote oneself to work, No. 2 big turbocharger and small turbocharger work at the same time at this time, turbine Circulation area increases, and small turbo charger speed will not be made to transfinite, while pressure ratio will not be too high, and air mass flow increases, and meets The air requirements of diesel engine medium-heavy duty.

(3) when diesel engine operates in high operating condition: air mass flow required for diesel engine works at this time increases, in (2) On the basis of open No. 1 air cutoff valve 17 and No. 1 gas shutoff valve 5, three turbocharger work at the same time at this time, turbine circulation Area is maximum, pressure ratio will not very high while total flow it is larger, meet the air requirements of the high operating condition of diesel engine.

When diesel engine operates in emission control area

(1) if diesel engine is in low condition range: NOx emission is relatively fewer, while mainly full under low operating condition The air inflow problem of sufficient diesel engine, so when diesel engine is in low operating condition, without EGR, close at this time No. 1 gas shutoff valve 5, No. 2 air cutoff valves 18 of air cutoff valve 17,2 of gas shutoff valve 6,1 and the control of small turbocharger air compressor exhaust gas Valve 7 opens No. 3 gas control valves 4, small turbocharger air compressor air shut-off valve 10 and standard-sized sheet EGR valve 19, cooler for recycled exhaust gas It does not work with EGR washer, at this moment only small turbocharger operation, turbine circulation area is smaller, and response is fast, turbine efficiency Height, acting ability is strong, can generate higher pressure ratio and flow, improves the acceleration and load response characteristic of low operating condition, meets bavin The air requirements of the low operating condition of oil machine.

(2) when diesel engine operates in medium-heavy duty, the gas valve 6,2 of No. 3 gas valves 4,2 air valve 18, small is opened Turbocharger air compressor exhaust gas control valve 7, EGR valve 19 keep certain aperture, and it is empty to simultaneously close off small turbocharger air compressor Gas control valve 10, at this moment EGR washer 8 and cooler for recycled exhaust gas 9 are started to work, No. 2 big turbocharger and small turbocharging at this time Device works at the same time, and No. 2 13 entrances of big turbocharger air compressor connect atmosphere, small 15 entrance of turbocharger air compressor connection warp Washing and exhaust gas after cooling will lead in this way into the specific heats of gases in inlet manifold 2 and holds increase, and oxygen content reduces, finally Maximum combustion temperature is caused to reduce, NOx emission reduces, simultaneously because supercharged diesel engine excess air coefficient is larger, in exhaust gas Containing a large amount of oxygen, so the useless internal oxygen content through too small turbocharger air compressor 15 is also higher not to will lead to air inlet collection Gas oxygen content is very low in pipe 2 and then influences combustion quality.

(3) when diesel engine operates in high operating condition, the combustion gas of air cutoff valve 17,2 of No. 1 gas shutoff valve 5,1 is opened The air valve 18,3 of valve 6,2 gas valve 4, small turbocharger air compressor exhaust gas control valve 7, EGR valve 19 keep certain aperture, Small turbocharger air compressor air shut-off valve 10 is simultaneously closed off, at this moment EGR washer and cooler for recycled exhaust gas are started to work, at this time Three turbocharger work at the same time, and 1, No. 2 big turbocharger air compressor 11,13 entrances connect atmosphere, small turbocharger pressure 15 entrance of mechanism of qi connects washed and after cooling exhaust gas, and total circulation area of turbine is maximum, and boost pressure will not be very high, simultaneously Maximum flow meets air required for high operating condition is burnt, while being entered in inlet manifold 2 by small turbocharger air compressor Exhaust gas can make the specific heats of gases in inlet manifold 2 hold increase, oxygen content reduce, eventually lead to maximum combustion temperature reduction, NOx Discharge reduces, simultaneously because supercharged diesel engine excess air coefficient is very big, a large amount of oxygen is also contained in exhaust gas, so through too small Oxygen content is also higher in the exhaust gas of turbocharger air compressor 15, not will lead in inlet manifold 2 gas oxygen content very it is low in turn Influence combustion quality.

Claims

1. three stage of the three turbocharger sequential turbocharging control method of function is realized with EGR, it is characterized in that:

Based on three stage of the three turbocharger sequential turbocharging device for realizing function with EGR, including exhaust header, air inlet Collector, No. 1 big turbocharger, No. 2 big turbocharger, small turbocharger, No. 1 big turbocharger include No. 1 and calm the anger Machine, No. 1 turbine, No. 2 big turbocharger include No. 2 compressors, No. 2 turbines, and small turbocharger includes small compressor, small whirlpool Wheel；The input end of No. 1 turbine is connected to exhaust header by No. 1 exhaust pipe, and the input end of No. 2 turbines passes through No. 2 exhaust pipe connections Exhaust header, the input end of small size turbine pass through small size exhaust pipe and are connected to exhaust header, the outlet end of No. 1 turbine, No. 2 turbines Outlet end, small turbine outlet end be connected to discharge manifold, delivery pipe is connected to atmosphere；No. 1 compressor, small is calmed the anger at No. 2 compressors The input end of machine is connected to inlet manifold, and inlet manifold one end is connected to atmosphere, and the other end is connected to EGR pipe, and EGR pipe connection discharge is total The outlet end of pipe, No. 1 compressor is connected to outlet general pipeline by No. 1 escape pipe, and the outlet end of No. 2 compressors passes through No. 2 escape pipes It is connected to outlet general pipeline, the outlet end of small compressor passes through small size escape pipe and is connected to outlet general pipeline, and outlet general pipeline is connected to by air inlet Pipe is connected to inlet manifold；No. 1 gas valve is installed on No. 1 exhaust pipe, No. 2 gas valves are installed on No. 2 exhaust pipes, on small size exhaust pipe No. 3 gas valves are installed, No. 1 air cutoff valve is installed on No. 1 escape pipe, No. 2 air cutoff valves are installed on No. 2 escape pipes, it is small size EGR valve is installed on escape pipe；

Small compressor air control valve is installed on the inlet manifold between No. 2 compressors and small compressor, EGR is installed in EGR pipe Cooler, EGR washer, small compressor exhaust gas control valve, air inlet install aerial cooler on communicating pipe；

When diesel engine operates in non-emission control area:

Small compressor air control valve is opened, and small compressor exhaust gas control valve is closed, and EGR washer and cooler for recycled exhaust gas are not involved in Work；

(1) when diesel engine is in low operating condition: No. 1 gas shutoff valve of closing, No. 2 gas shutoff valves, No. 1 air valve and No. 2 Air valve opens No. 3 gas control valves and standard-sized sheet EGR valve；

(2) when diesel engine operates in medium-heavy duty: opening No. 2 gas valves and No. 2 air on the basis of diesel engine low operating condition Valve makes No. 2 big turbocharger start to devote oneself to work, and No. 2 big turbocharger and small turbocharger work at the same time at this time；

(3) when diesel engine operates in high operating condition: opening No. 1 air cutoff valve and No. 1 on the basis of diesel engine medium-heavy duty Gas shutoff valve, three turbocharger work at the same time at this time；

When diesel engine operates in emission control area:

(a) when diesel engine is in low condition range: closing No. 1 gas shutoff valve, No. 2 gas shutoff valves, No. 1 air interception Valve, No. 2 air cutoff valves and small compressor exhaust gas control valve open No. 3 gas control valves, small compressor air control valve simultaneously Standard-sized sheet EGR valve；

(b) when diesel engine operates in medium-heavy duty: it is useless to open No. 3 gas valves, No. 2 gas valves, No. 2 air valves, small compressor Gas control valve, EGR valve, simultaneously close off small compressor air control valve, and EGR washer and cooler for recycled exhaust gas are started to work, and at this time 2 Number big turbocharger and small turbocharger work at the same time, and No. 2 compressor inlets connect atmosphere, small compressor inlet connection warp Washing and exhaust gas after cooling；

(c) when diesel engine operates in high operating condition: opening No. 1 gas shutoff valve, No. 1 air cutoff valve, No. 2 gas valves, No. 2 skies Air valve, No. 3 gas valves, small compressor exhaust gas control valve, EGR valve, simultaneously close off small compressor air control valve, EGR washer It starts to work with cooler for recycled exhaust gas, three turbocharger work at the same time at this time, and No. 1 compressor, No. 2 compressor inlets connect atmosphere, Small compressor inlet connects washed and after cooling exhaust gas.