CN205445831U - Satisfy exhaust gas recirculatioon constant voltage equipment of high supercharging than engine adaptive control - Google Patents

Abstract

The utility model provides a satisfy exhaust gas recirculatioon constant voltage equipment of high supercharging than engine adaptive control, set gradually electric booster pump, cooler, energy storage ware on including the exhaust gas circulation route between engine exhaust manifold and air intake manifold, and the controller, the inlet set of the energy storage ware check valve that admits air, the gas outlet sets up discharge valve, is equipped with energy storage ware pressure sensor in the energy storage ware, be equipped with back pressure transducer between engine and exhaust manifold, energy storage ware pressure sensor, exhaust pressure sensor, electric booster pump, energy storage ware discharge valve all are connected with the controller, and the controller is connected with festival valve opening sensor. Set up pressure boost, energy storage equipment in the exhaust gas circulation pipeline, the pressure of maintaining waste gas is invariable for engine application EGR reduces NOx's smooth implementation of technique. Simultaneously, through adaptive control energy storage ware discharge valve's aperture and the time, adjust EGR and rate, satisfy the requirement that the engine reduces NOx.

Description

A kind of exhaust gas recirculatioon constant voltage equipment meeting high pressure engine Self Adaptive Control

Technical field

This utility model relates to engines exhaust gas recirculation technology, particularly to a kind of exhaust gas recirculatioon constant voltage equipment meeting high pressure engine Self Adaptive Control.

Background technology

Using exhaust gas recirculatioon (EGR) in electromotor is by reducing burning velocity, reduces maximum combustion temperature and the persistent period of high temperature, thus destroys NO_xHigh-temperature oxygen-enriched condition needed for generation, reduces the NO of electromotor_xDischarge.EGR technology is to reduce NO_xOne of effective measures discharged pollutants, current EGR technology is applied relatively broad on middle-size and small-size vehicular engine.

Meanwhile, research finds, in the case of not taking other measures, and NO_xAnd between exhaust particulate (PM), there is the curve linear relationship of balance (trade-off).Under small engine load, the discharge on PM that increases of EGR rate affects less；And the increase of EGR rate makes PM amplification relatively big under middle high load capacity, need to limit EGR rate.So, analyzed by comprehensive, during Smaller load, can use bigger EGR rate, and centering high load capacity, then need regulation EGR rate, EGR rate is limited.

At present, the technical measures that EGR is taked are, arrange waste gas circulation path between enmgine exhaust and inlet manifold, and a part for the waste gas discharged by electromotor sends cylinder again back to.Under middle high load capacity, pressure at expulsion and temperature are the biggest, enter cylinder easily by closed circuit under the control of EGR valve；And during Smaller load, pressure at expulsion is relatively low with temperature, in engine with supercharger, high supercharging pressure level makes that waste gas is more difficult is passed through cylinder especially.So, take certain measure to improve portion pressure, reduce in the case of high supercharging pressure level, waste gas flows back to the technical difficulty of cylinder, for reduce the discharge of electromotor NOx in the urgent need to.

Utility model content

This utility model is for the deficiencies in the prior art, it is provided that a kind of EGR constant voltage equipment meeting high pressure engine Self Adaptive Control, suitably controls EGR rate according to engine with supercharger workload, reduces NO_xDischarge.

This utility model realizes above-mentioned technical purpose by techniques below means.

A kind of EGR constant voltage equipment meeting high pressure engine Self Adaptive Control, it is characterised in that: set gradually electric booster pump, cooler, accumulator, and controller on the waste gas circulation path being included between enmgine exhaust and inlet manifold；Described accumulator is used for storing waste gas constant pressure, and the air inlet of accumulator is provided with breather check valve, and gas outlet arranges air bleeding valve, is provided with energy storage pressure sensor in accumulator；It is provided with back pressure transducer in pipeline between electromotor and exhaust manifold；Described energy storage pressure sensor, back pressure transducer, electric booster pump, accumulator air bleeding valve are all connected with controller, controller engine load sensor existing with intake channel is connected, described controller controls the breather check valve of the start and stop of electric booster pump, accumulator then according to energy storage pressure sensor, back pressure transducer and engine load sensor output signal, and gas outlet arranges the opening and closing of air bleeding valve.

Further, the pipe diameter of described waste gas circulation path is 35～45mm.

Further, the volume of described accumulator is

m_EG/(m₁+m_EG)=[η_EGR]

$m_{EG}=\frac{\[{\mathrm{\η}}_{EGR}\]}{1-\[{\mathrm{\η}}_{EGR}\]}{m}_1$

The equation of gas state: P_EGV=(m_EGRT/M)=nRT

Wherein: m₁For often circulating actual fresh charge；

m_EGFor every cycle gas quality；

[η_EGR] it is maximum EGR rate in electromotor；

V accumulator volume；

M ideal gas molal weight；

The amount of n material；

R gas constant；

P_EGConstant exhaust gas pressure in accumulator, takes 1.3～1.5 times of atmospheric pressure.

Further, maximum EGR rate [η in electromotor_EGR] take 40%.

Further, the air-breathing turbine of described electric booster pump, exhaust driven gas turbine all use exotic material.

Exhaust gas recirculatioon technology (EGR) is used to reduce NO_xThe supercharged diesel engine of discharge and inner cylinder direct injection supercharging gasoline engine are when partial load condition runs, pressure at expulsion is relatively low, after using supercharging technology, admission pressure in air inlet pipe, apparently higher than exhaust gas pressure in EGR device, causes the waste gas in EGR device and is difficult to enter the phenomenon of engine air inlet tube.In this utility model, electric booster pump is used for improving exhaust gas pressure, and its feature is that response and controllability are good, and maximum (top) speed is up to 50000r/min.Accumulator is used for storing waste gas constant pressure.Use accumulator, play storage waste gas and constant exhaust gas pressure is 1.3～1.5 times of atmospheric pressure, enter inlet manifold smoothly with the waste gas of 1.3～1.5 times of constant atmospheric pressure, be mixed into cylinder with air.Use Experimental Calibration method, by control unit according to engine operation condition more accurately controls accumulator air bleeding valve under different operating modes aperture size and the time, regulate EGR rate, reduction NOx emission.

Arranging supercharging, energy storage equipment in waste gas circulation pipeline, the pressure maintaining waste gas is constant so that electromotor uses waste gas circulation (EGR) to reduce NO_xTechnology implement smoothly.Meanwhile, by aperture and the time of Self Adaptive Control accumulator air bleeding valve, regulate EGR rate, meet electromotor and reduce NO_xRequirement.

The PFE Exhaust Pressure Transducer being installed in accumulator is exhaust gas pressure in detecting accumulator, when playing that exhaust gas pressure is less than required scope in the effect of Self Adaptive Control, i.e. accumulator, control unit controls EGR electric booster pump and runs；When in accumulator, exhaust gas pressure reaches required scope, control unit controls EGR electric booster pump operation suspension.By the signal such as engine operation condition and TPS, the start-up time of EGR accumulator air bleeding valve, and determined aperture and the opening time of EGR accumulator air bleeding valve by Experimental Calibration method, regulate suitable EGR rate.

Accompanying drawing explanation

Fig. 1 is the structure chart of the EGR constant voltage equipment meeting high pressure engine Self Adaptive Control described in the utility model.

Fig. 2 is Self Adaptive Control flow chart of the present utility model.

Fig. 3 is operation principle flow chart of the present utility model.

In figure:

1-EGR admission line；2-EGR cooling liquid outlet；3-EGR cooler；4-EGR coolant inlet；5-accumulator breather check valve；6-energy storage pressure sensor；7-accumulator；8-accumulator air bleeding valve；9-inlet manifold；10-electromotor；11-back pressure transducer；12-electronic EGR booster pump energising port；13-exhaust manifold；14-exhaust gas processing device；15-booster pump air-breathing turbine；16-electronic EGR booster pump；17-booster pump exhaust driven gas turbine.

Detailed description of the invention

Below in conjunction with the accompanying drawings and this utility model is further described by specific embodiment, but protection domain of the present utility model is not limited to this.

As inscribed shown in 1, the exhaust gas recirculatioon constant voltage equipment meeting high pressure engine Self Adaptive Control described in the utility model, it is characterized in that: on the waste gas circulation path being included between enmgine exhaust and inlet manifold, set gradually electric booster pump 16, cooler 3, accumulator 7, and controller；Described accumulator 7 is used for storing waste gas constant pressure, and the air inlet of accumulator 7 is provided with breather check valve 5, and gas outlet arranges air bleeding valve 8, is provided with energy storage pressure sensor 6 in accumulator 7；Back pressure transducer 11 it is provided with in pipeline between electromotor and exhaust manifold；Described energy storage pressure sensor 6, back pressure transducer 11, electric booster pump 16, accumulator air bleeding valve 8 are all connected with controller, controller engine load sensor existing with intake channel is connected, described controller controls the breather check valve 5 of the start and stop of electric booster pump 16, accumulator 7 then according to energy storage pressure sensor 6, back pressure transducer 11 and engine load sensor output signal, and gas outlet arranges the opening and closing of air bleeding valve 8.

The air-breathing turbine 15 of described electric booster pump 16, exhaust driven gas turbine 17 all use exotic material.Booster pump uses motor to drive, and response and controllability are good, and maximum (top) speed, up to 50000r/min, can improve the pressure of waste gas.

Owing to using the mode of supercharging, exhaust gas flow, pressure increased with flow velocity, for reducing exhaust gas pressure decay, so the pipeline that in this device, the diameter of waste gas circulation pipeline compares to nowadays apply reduces by 6 10mm.The pipe diameter of described waste gas circulation path is 35～45mm.

Accumulator, plays storage waste gas and constant exhaust gas pressure is 1.3～1.5 times of atmospheric pressure, enters inlet manifold smoothly with the waste gas of 1.3～1.5 times of constant atmospheric pressure, is mixed into cylinder with air, and accumulator volume is

The calculating of accumulator volume

When diesel engine runs under Smaller load, can suitably increase EGR rate, maximum EGR rate is up to 40%.So, under Smaller load, on the basis of maximum EGR rate 40%, carry out the calculating of accumulator volume:

Total air mass m=actual fresh charge m₁+ exhaust mass m_EG

m_EG/(m₁+m_EG)=[η_EGR]

$m_{EG}=\frac{\[{\mathrm{\η}}_{EGR}\]}{1-\[{\mathrm{\η}}_{EGR}\]}{m}_1$

Wherein: m₁For often circulating actual fresh charge

m_EGFor every cycle gas quality

[η_EGR] it is maximum EGR rate in electromotor

The equation of gas state: P_EGV=(m_EGRT/M)=nRT

$V=\frac{m_{EG}RT}{P_{EG}M}$

Wherein: V accumulator volume；

M ideal gas molal weight；

The amount of n material；

R gas constant；

P_EGConstant exhaust gas pressure in accumulator, takes 1.3～1.5 times of atmospheric pressure.

Electromotor 10 runs, and piston, intake and exhaust are working properly, and electric booster pump 16 starts running.Waste gas after supercharging, by cooler 3, makes EGT be reduced.Accumulator breather check valve 5 is opened, and waste gas is stored in accumulator 7 by circulation duct.The pressure transducer 6 being installed in accumulator detects exhaust gas pressure.When in accumulator, exhaust gas pressure reaches 1.3～1.5 times of atmospheric pressure, control unit controls EGR electric booster pump 16 operation suspension.Control unit, according to the signal such as engine operation condition and TPS, controls accumulator exhaust valve opening and time, regulates EGR rate.Being embodied in, use the electromotor of EGR technology when Smaller load runs, control accumulator exhaust valve opening and suitably increase, the opening time extends；In electromotor under high load capacity, suitably controlling accumulator exhaust valve opening and suitably reduce, the time suitably shortens, and especially closes EGR under high load capacity.Accumulator air bleeding valve 8 is opened, and the waste gas after supercharging enters inlet manifold smoothly, subsequently into cylinder.

As in figure 2 it is shown, shown in Fig. 3, the control method of described constant voltage equipment, specifically include following steps:

1) Self Adaptive Control in accumulator: electromotor runs, electric booster pump 16 brings into operation, improve exhaust gas pressure, after waste gas enters cooler for recycled exhaust gas 3, temperature reduces, waste gas after cooling enters accumulator 7 by cooler rear end pipeline by accumulator breather check valve 5, the PFE Exhaust Pressure Transducer 6 being installed in accumulator 7 detects exhaust gas pressure in real time, and the exhaust gas pressure signal of telecommunication is exported to controller, when exhaust gas pressure is less than 1.3～1.5 atmospheric pressure, control unit controls electric booster pump 16 and runs；When exhaust gas pressure reaches 1.3～1.5 atmospheric pressure, suspend electric booster pump 16；

2) Self Adaptive Control of accumulator air bleeding valve: control unit combines signal and the engine operation condition signal of TPS output, aperture and the time parameter of accumulator air bleeding valve 8 under middle Smaller load is determined by Experimental Calibration, regulation EGR rate, accomplish to reduce electromotor pollutant emission, improve engine power performance, it is embodied in: when the electromotor using EGR technology runs at Smaller load, the discharge on PM that increases of engine EGR rate affects less, according to accumulator exhaust valve opening and time parameter determined by Experimental Calibration, use the EGR rate suitably increased；The increase of EGR rate but makes PM amplification relatively big, so by accumulator exhaust valve opening and time parameter determined by Experimental Calibration, controlling accumulator exhaust valve opening and reduce, the time shortens, and uses closedown EGR under less EGR rate especially high load capacity.

Described embodiment be of the present utility model preferred embodiment; but this utility model is not limited to above-mentioned embodiment; in the case of without departing substantially from flesh and blood of the present utility model, any conspicuously improved, replacement or modification that those skilled in the art can make belong to protection domain of the present utility model.

Claims (5)

1. the exhaust gas recirculatioon constant voltage equipment meeting high pressure engine Self Adaptive Control, it is characterized in that: on the waste gas circulation path being included between enmgine exhaust and inlet manifold, set gradually electric booster pump (16), cooler (3), accumulator (7), and controller；Described accumulator (7) is used for storing waste gas constant pressure, the air inlet of accumulator (7) is provided with breather check valve (5), gas outlet arranges air bleeding valve (8), is provided with energy storage pressure sensor (6) in accumulator (7)；Back pressure transducer (11) it is provided with in pipeline between electromotor and exhaust manifold；Described energy storage pressure sensor (6), back pressure transducer (11), electric booster pump (16), accumulator air bleeding valve (8) are all connected with controller, controller is connected with the engine load sensor in intake channel, described controller controls the breather check valve (5) of the start and stop of electric booster pump (16), accumulator (7) then according to energy storage pressure sensor (6), back pressure transducer (11) and engine load sensor output signal, and gas outlet arranges the opening and closing of air bleeding valve (8).

Constant voltage equipment the most according to claim 1, it is characterised in that: the pipe diameter of described waste gas circulation path is 35～45mm.

Constant voltage equipment the most according to claim 1, it is characterised in that: the volume of described accumulator (7) ism_EG/(m₁+m_EG)=[η_EGR]

The equation of gas state: P_EGV=(m_EGRT/M)=nRT

Wherein: m₁For often circulating actual fresh charge；

m_EGFor every cycle gas quality；

[η_EGR] it is maximum EGR rate in electromotor；

V accumulator volume；

M ideal gas molal weight；

The amount of n material；

R gas constant；

P_EGConstant exhaust gas pressure in accumulator, takes 1.3～1.5 times of atmospheric pressure.

Constant voltage equipment the most according to claim 2, it is characterised in that: maximum EGR rate [η in electromotor_EGR] take 40%.

Constant voltage equipment the most according to claim 1, it is characterised in that: the air-breathing turbine (15) of described electric booster pump (16), exhaust driven gas turbine (17) all use exotic material.