GB2561932A

GB2561932A - Clean diesel & other eco-boost engines with throttled exhaust systems

Info

Publication number: GB2561932A
Application number: GB1713047.7A
Authority: GB
Inventors: John Bayram Peter
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-04-28
Filing date: 2017-08-15
Publication date: 2018-10-31
Also published as: GB201713047D0

Abstract

An internal combustion engine may be fitted with an exhaust gas driven turbine 6 coupled to a motor generator 2. The motor generator may be connected via a continuously variable transmission (CVT) unit 3 to an engine crankshaft 4. The system may be used to start a vehicle. In a second embodiment a turbocharger having an exhaust gas driven turbine 10 is connected to a motor generator 10 and to a compressor 2. An intercooler 4, cooled by a fan 5 may be fitted. A second motor generator 17 may be coupled via a CVT unit 19 to an engine crankshaft 22. The speed of the turbine or turbocharger may be varied by the motor generator and vice versa. Sensors measure engine and vehicle parameters and send signals to an ECU which may be self-learning. The turbine, turbocharger motor generator may be operated in differing modes dependent upon the vehicles status i.e. start up, normal running, regenerative braking, temperature of catalytic convertor. A battery pack may be used to store power from the generator. The system may be used for petrol or diesel internal combustion engines. The motor generator may transmit mechanical or electrical power.

Description

(56) Documents Cited:

GB 2533664 A GB 2450957 A US 6568173 B1 US 20100107632 A1

GB 2533661 A WO 2014/158077 A1 US 20120137681 A1 (71) Applicant(s):

Peter John Bayram 13 Glamorgan Road, Hampton Wick, KINGSTON UPON THAMES, Surrey, KT1 4HS, United Kingdom (58) Field of Search:

Other: WPI, EPODOC (72) Inventor(s):

Peter John Bayram (74) Agent and/or Address for Service:

Peter John Bayram 13 Glamorgan Road, Hampton Wick, KINGSTON UPON THAMES, Surrey, KT1 4HS, United Kingdom (54) Title of the Invention: Clean diesel & other eco-boost engines with throttled exhaust systems

Abstract Title: Control system for turbine or turbocharger and variable speed motor generator for power transmission.

(57) An internal combustion engine may be fitted with an exhaust gas driven turbine 6 coupled to a motor generator 2. The motor generator may be connected via a continuously variable transmission (CVT) unit 3 to an engine crankshaft 4. The system may be used to start a vehicle. In a second embodiment a turbocharger having an exhaust gas driven turbine 10 is connected to a motor generator 10 and to a compressor 2. An intercooler 4, cooled by a fan 5 may be fitted. A second motor generator 17 may be coupled via a CVT unit 19 to an engine crankshaft 22. The speed of the turbine or turbocharger may be varied by the motor generator and vice versa. Sensors measure engine and vehicle parameters and send signals to an ECU which may be self-learning. The turbine, turbocharger motor generator may be operated in differing modes dependent upon the vehicle’s status i.e. start up, normal running, regenerative braking, temperature of catalytic convertor. A battery pack may be used to store power from the generator. The system may be used for petrol or diesel internal combustion engines. The motor generator may transmit mechanical or electrical power.

=.- ^-=. VOCTAOE =*25^ feX-HAUST

13

ID

ΙϊΖ tf ···

2/3 • · • · • ··· • · · • I » ·· ···

• ί ··· ·

3/3

CO ώ

&

□ ί

Intellectual

Property

Office

Application No. GB1713047.7

RTM

Date :12 February 2018

The following terms are registered trade marks and should be read as such wherever they occur in this document:

ECOBOOST

Intellectual Property Office is an operating name of the Patent Office www.gov.uk/ipo

	CONTROL SYSTEMS for ’CLEAN’ DIESEL & OTHER ECO-BOOST ENGINES with THROTTLED EXHAUST SYSTEMS
1	This invention relates to the possible throttle and emissions control systems of i.e. engines in which there are no intake system throttle control butterfly valves, i.e. those with, at
5	least, a controllable adiabatic engine in their exhaust system. When i.e.engines have throttle controlled adiabatic engines in their intake systems, as in eco-boost engines, adiabatic expanpansion cooling of less than hot intake air is liable to cause intake manifold freeze-up. Such is conventionally obviated by
ΙΟ	run-around systems that transfer exhaust heat to intake air/ intake manifolds. However, such run—around systems not only prevent the possibility of efficiency increasing tuned-pipe exhaust headers be-
15	ing used but also incur a cost penalty. Furthermore, in ecoboost i.e.engines such run-around system transfer of heat from their exhaust system cools exhaust gases such that less heat energy can be extracted from their exhaust gases than otherwise would be the case. Also adiabatic engine throttling of normally
20	aspirated i.e. engines has been disregarded because such throttling only involves the extraction of heat energy from ambient air, which sometimes is freezing cold, whereas an eco-boost en—
• · • t • ···	gine also extracts heat, energy from much hotter exhaust gases, particularly during high turbo boost pressures. It is known
es	(**) that these problems can be overcome by the use of usefully throttled adiabatic engines in normally aspirated i.e.engines’
• · · • · · • · ·	exhaust systems, use of usefully throttled turbochargers with bypasses in turbocharged i.e.engines and use of bypasses around
• • · · • 30	usefully throttled adiabatic engines in eco-boost i.e.engines that enables prevention of expansion cooling freeze—up in their
» · · » · ·	i.e. engine intake ystems during low and sub-zero ambient conditions whilst at the same time increasing useful adiabatic en-
	gine throttling of the i.e.engine’s exhaust gases. Such useful
• · 35	throttling, or increased throttling (adiabatic cooling) of exexhaust gases for any given i.e.engine throttling effect genet— ates more power output than intake air throttling because the absolute temperature and pressures of the exhaust gases are significantly higher such that for the same %age drops in them the drop measure of the exhaust gases would be higher than the
40	intake air measure drop, or to put it another way the expansion cooling of the combustion gases that occurs in i.e.engines is further expansion cooled by any adiabatic engines in their exhaust systems, particularly when they are throttling the flow of exhaust gases (which is not to say that controllable ones
45	necessarily always expansion cool); it is as if an i.e.engine’s expansion stroke has become longer than its compression stroke. CIt should be noted that the use of throttle controlled adiabatic engines in the intakes of normally aspirated i.e.engines, whilst theoretically possible, is impractical because during
50	low, and particularly during sub-zero ambients further cooling by expansion cooling makes it more difficult to maintain adequate i.e.engine operating temperatures (and run-around system heat exchanger gas flow pressure losses negate some of the

ΙΟ • · • · • ··· ······

• ·· • · · » · · gains From adiabatic throttling)» whereas the use of throttle controlled adiabatic engines in the exhausts of normally aspirated engines helps to maintain adequate i.e.engine operating temperatures when idling during sub-zero ambients because of the exhaust back-pressures generated by such throttling» and also there is no run—around system incurring losses. N. B. The power output of said adiabatic engines when idle-thrott1ing is used to lower idle rpm which helps to avoid i.e.engine overheating during high ambient temperature conditions.

(**> fts divulged in Bayram’s patent application GB1209146.β.s Control of a Diesel Engine’s Exhaust Condition to Improve Catalytic Convertor Efficacy, tin particular» the final claims» as filed on the 14th of October, 201&, can be said to be the precursor of this invention.!

In such aforementioned i.e.engines there are exhaust turbines or reverse—acting positive displacement exhaust pumps, turbochargers with exhaust turbines and centrifugal air compressors, and superchargers which can be adiabatic expansion (cooling) engines, or adiabatic compression (heating) engines, or adiabatic compression-expansion engines. However, they can most conveniently, concisely, and ’broadly’, all be described as adiabatic engines, especially for ones whose function changes when their speed is sufficiently varied.

Such ways of throttling exhaust gases can be applied to Diesel engines, diesel-glo engines and diesel fueled glo-engines to minimise their exhaust gas NOX and particulate soot emissions when controllable adiabatic engines are connected to a control system connected to Lambda/02 sensors (wideband, or otherwise) in their exhausts, and which conventionally is also connected to fuel flow varying means. In this way the use of catalytic convertors is enabled without necessarily requiring the use of urea injection systems, which ideally should be upstream of adiabatic engines in the exhaust system and which could be mini ones close to each i.e.engine exhaust port. Which is not to say that such cannot also be applied to all other types of i.e.engines, including turbojets. Particularly in Diesel engines, exhaust heat temperature sensors can be used in lieu of Lambda/02 sensors to indirectly control their NOX and soot particulate emissions, which in either case also indirectly controls such engines’ combustion efficiency.

Conventionally Diesel and jet engines have throttle controlled fuel supply systems and petrol/spark ignition engines have throttle controlled intake air/charge-air systems, which now also includes indirect control by means of throttle controlling exhaust systems or even sometimes throttle controlling one whilst at the same time throttling the other one in a compensating unified way. As such, conventionally two (2) different

i.e.engine throttle control systems (TCSs) exist for basically different types of i.e.engines, requiring two (2) different engine management computer Unit (ECU) software programmes, and detected failure in any part of them will stop the i.e.engine, or at least cause rough running. To overcome these problems the present invention proposes that the ECU’s of any i.e.en55 gines having at least one (1) controllable adiabatic engine in its exhaust system be programmed for the TCS to control any such controllable adiabatic engines and for the exhaust emissio control system to control the fuel flow system, or, vice versa, for the TCS to control the fuel flow system and for the exhaust emissions control system to control exhaust system controllable adiabatic engines. It is also possible for the ECU to incorporate both such operating modes and be programmed in such a way that they frequently change, randomly or otherwise, from one to the other, or change from one mode to the other in the event that a fault is detected in one, or pulse-modulate change from one mode to the other to obtain limp—home operation when there is fuel flow in one mode and gas flow in the other. It is anticipated that the hysteresis delay times of fuel flow control systems and gas flow control systems will be different so that, at least in prototype form, an ECU should have a selflearning programme to determine optimum proportional control bands and whether or not derivative, or derivative + integral controls are also required to meet whichever performance criteria may need to met or have been selected, and also determine which mode may be optimal, and since any two electro-mechanical systems are unlikely to be the same they should be individually learned.

Such exhaust throttled i.e.engines can have their controllable adiabatic engines connected to power accumulating—discharging means such as a battery-pack since such adiabatic engines can output power during throttle lift-offs, and can be used to pneumatically brake the i.e.engine and thereby any drivetrain connected to it such that said adiabatic engines output power (brakehorsepower) , and such power accumulating-discharging means can also be connected to wheel hub motoi—generators (M-G*s) and/or M-G* s mechanically connected to a respective

i.e.engine. Such power as is accumulated (limited to prevent over-charging) can be discharged (also limited to obviate excess depletion) to the aforementioned M-G*s and to M-G’s connected to adiabatic engines for them to generate boost pressures when extra acceleration (but less economy) is required. All as may be limited by means preventing overloads in each of the aforementioned system parts.

Typical examples of the invention are now described by way of reference to the accompanying schematic drawings, in whichs

Figure 1 shows an exhaust emission control system for normally aspirated i.e. petrol engines having throttle controlled fuel supply^ systems.

Figure 2 shows a similar exhaust emission control system for turbocharged i.e. petrol engines that also have throttle controlled fuel supply systems.

Figure 3 is a figure 2 system with the addition of a supercharger sequentially controlled with the turbocharger.

In Figure i: upon start—up, valve 1 closes and motor-generator (M—G) 2 is energised, and it’s speed is stepped—down by contin4

ΙΟ • · • · • ··· • · • · · • · • · · • · · • ·

I · · • · · · ft · uously variable transmission (CVT) 3 (in low gear at shutdown) so that i.e. engine crankshaft 4 is rotated at low rpm, such that the i.e. engine increases the pressure and temperature of the air in it’s exhaust system upstream of throttle valve (TV) until a set pressure, sensed by sensor 5, is achieved. When such pressure is achieved, fuel-injection to the petrol engine is commenced and TV 1 simultaneously opened, releasing the energy of the compressed air into the exhaust system such that it powers turbine 6, inputting power to M-G 2 to boost it’s starting torque/speed (such that no starter ring gear is required). At wide-open-throttle (wot) fuel injection rate, throttle valve (TV) 7 is wide open such that the parasitic drag of turbine 6 does not throttle the engine at wot. At less than wot, sequentially, valve 7 is modulated and turbine 6’s speed is varied in response to output signals from 02 sensor β via the engine’s ECU processor to CVT 3’s actuator 9, and M-G 2 is switched-off. Such speed variation of turbine G variably throttles the flow of the engine’s exhaust gases, thereby indirectly varying engine intake airflow to obtain not only optimum combustion air/ fuel ratios during varying fuel injection rates, but also high exhaust gas temperatures at low fuel injection rates, keeping catalytic converter IO lit at such times. Uith M-G 2 switched -off, the power output of turbine &, derived from it’s throttling of the exhaust gases, is input to engine crankshaft 4 via CVT 3 which variably brakes turbine 6’s higher relative speed to that of the engine’s crankshaft. Upon ’throttle’ lift-off fuel injection cessation exhaust turbine 6 throttles air from the exhaust manifold, compressing and heating it, such that such heating reduces catalytic converter 10’s temperature dropoff, whilst at the same time outputting power to engine crankshaft 4, such that there is little nett braking effect upon the drivetrain. Upon a demand for vehicle braking from the vehicle’s braking system, via the ECU, actuator 9 locks-up CVT 3 and the nominal speed of M-G 2 is proportionaily reduced by it’s speed controller 11 such that M-G 2 outputs power to power absorbing means such as a battery-pack - as and when such means become fully charged a feed-back signal from it’s charge controlling means is fed to speed controller 11 to increase M-G 2’s nominal speed up to it’s actual speed such that all vehicle braking becomes mechanical via it’s wheels. In reverse, such stored energy would be released via M—G 2 when it’s nominal speed is increased above it’s actual speed, inputting power to the vehicle’s drivetrain via engine crankshaft 4, such that when steady state cruising or idling the fuel injection rate would thereby be reduced and, consequentially, the throttling and power output of turbine 6 would also be increased - also, maximimum wot fuel injection rate acceleration can be similarly increased since at wot TV 7 would be wide open such that there would be no throttling of the engine’s exhaust gases. In this example, turbine & is a turbocharger’s radial flow turbine whose spirally rotating discharge is de-rotated by radial outlet volute 12 to increase turbine 6’s power output in the order of 25 to 30*, and, likewise, energy recovery from the engine’s exhaust gases when they are being throttled by turbine 6. However, turbine 6 could be a positive displacement type such as a Wankel rotary engine (without fuel injection and spark ignition); an off-the-shelf Roots type supercharger would not be

1	suitable for use with exhaust gases. ( In Figure 2: radial inlet volute 1 pre-rotates intake air to centrifugal compressor 2 whose discharge, when not bypassed
5	when TV 3 is open, is cooled by intercooler 4 whose cooling capacity is increased when fan 5 is switched-on, except when diverting valve 6 bypasses compressor 2’s discharge around it. Freeze sensor 7, via the engine’s ECU, modulates open TV 3 as and when cold ambient intake air is being adiabatically expan-
ΙΟ	sion refrigerated excessively by compressor 2 when it is being braked by M-G 8 during throttle lift-off coast-down, downhill coasting and engine start—up conditions (whose nominal speed can be varied by it’s speed controller 9) such that during such conditions M—G 8 would increasingly throttle brake radial tur-
15	bine IO, whose discharge is de-rotated by volute 11. At lower ambient temperatures maximum intake manifold charge air boost pressure would be limited by braking compressor 2 and turbine 10, in response to outputs from pressure sensor 12 via the ECU to speed controller 9, but when exhaust gas temperatures rise
20	above a set point at higher ambient conditions (as they will tend to do when there is high boost pressure, reduced inter— cooling, high exhaust throttling and high fuel injection), exhaust gas sensor 13, via the ECU, modulates open TV 14 and 02 sensor 16, via the ECU, compensatingly reduces the fuel injec-
25	tion rate. If the exhaust gas temperature falls below a point
• · • · • ··· •	insufficient to keep catalytic convertor 15 lit, in sequence, fan 5 is switched-off, valve 6 diverts intake air around intet— cooler 4, TV 3 is modulated open (such that all 02 sensor 16
• · 30 • · · • · · • ··	throttling becomes transferred to turbine IO, as it does upon throttle lift-off). M-G 17, speed controller 18, CVT 19, it’s actuator 20, shut-off valve 21 plus engine crankshaft 22 are all operated together in the same way as described for those
• • · · •	same elements in the Figure 1 system, excepting power transmission between turbine IO and crankshaft 22 is transferred in-
35 » · · • · ·	directly via M-G 17.
···· •	In Figure 3: during high ambient temperatures and wot fuel in-
• ·	jection rates M-G 1 is electrically disconnected such that radial exhaust turbine 2, whose discharge is de-rotated by radial
40	outlet volute 3, directly drives centrifugal compressor 4 whose intake air is pre—rotated by radial inlet volute 5. Compressor 4’s hot high pressure discharge air is cooled by intercooler 6 and fan 7, and is then pressure reduced by turbine & such that it is adiabatically expansion refrigerated. Turbine 8*s speed,
45	relative to engine crankshaft 9’s, is varied by CVT IO whose gearing is varied by actuator 11 in response to output signals from pressure sensor 12, via the ECU, which limits the manifold charge air pressure at such conditions. As fuel injection rates reduce at such conditions, 02 sensor 13, via the ECU, outputs
50	signals to CVT actuator 11 to reduce CVT IO’s gearing and the speed of throttling turbine 8. As ambient temperatures drop, to obviate intake manifold freeze-up due to excessive ait—cycle refrigerating by the above mentioned air intake system, freeze sensor 14 outputs control signals, via the ECU, to the air in-
55	take equipment so that, sequentially: fan 7 is switched-off; diverting valve 15 modulates open and TV 16 modulates open, and during throttle lift-off TV 21 is modulated open to obviate

compressor' 4 acting as an adiabatic expansion refrigerator. As diverting valve 15 modulates open then TV 16 modulates open. Os TV 16 modulates open, compensatingly, M-6 1 is activated and it’s nominal speed relative to it’s actual speed is modulating5 ly reduced by it’s speed controller 17 such that exhaust gases begin to be throttled by turbine 2, increasing exhaust gas temperatures which, particularly at sub-zero ambient temperatures, minimises catalytic convertor 16’s temperature drop-off. Except during throttle lift-off, any power output from turbine 8 is

IO transmitted via CVT 10 to engine crankshaft 9 - M-G 19’s nominal speed being controlled by it’s actuator 20 to be the same as it’s actual speed, except when there is also power output from M-G 1 into it when it’s nominal speed is reduced such that it outputs power into crankshaft 9. During throttle lift-off, CVT

IO’s gearing is locked Isl such that the powered vehicle’s brake control system can brake it by inputting, via the ECU, a control signal to M-G 19’s speed controller 20 to reduce it’s nominal speed to less than it’s actual speed such that M-G 19 exerts a braking effect upon engine crankshaft 9 (but only when such engine is in-gear), and, as priorly mentioned, during low temperature ambients, TV 21 is opened. Start-up operation is similar to the Figure 1 & 2 systems, wherein TV’s 21, 22 & 16 are closed, diverting valve 15 opened, M-G’s 1 4 19 energised, CVT IO motored in to low gear by actuator 11 until pressure sensor 23 is satisfied, whereupon TV 22 is opened and fuel injection commenced. If it is required to limit the throttling

J pressure differential across turbine 6, as might be the case , with the rotor tip seals of a Roots type supercharger, as sen*·***! sed by the pressure difference between sensors 25 and 12, modu30 lated opening of TV 24 would accordingly reduce turbo boost ,·.··. pressures, or a Wankel rotary engine (without fuel injection • ·· and spark ignition) could be used.

·· ·

In the Figure 1, 2 & 3 systems: fuel injection may be mechanic, .. 35 ally controlled manually via a foot or hand pedal, or electron’.J..· ically controlled from a throttle position sensor (TPS) sensing • the movement of such pedals and their rate-of-movement and or • *· by autonomous means such as cruise—contro1, or radar, etc., and there may also be control inputs from other sensors such as 40 a mass airflow sensor, 02 sensors per cylinder, etc.,

In all three (3) Figures, respectively, bypass valves 13, 23 and 26 open upon throttle lift-off and subsequently close upon vehicle braking or throttle tip-in such that whilst open resi45 dual i.e.engine heat is recirculated and air is obviated from being pumped through the insulated downstream exhaust system and catalytic convertor so that loss of residual heat from them is minimised.

Claims

CLAIMS!

1 1) Means for controlling an internal combustion (i.e.) engine having one <11, or «ore, adiabatic engines in its one <11, or ore exhaust systems, of which one (1), or more, of said adiabatic engines have means for transmitting power between them and the i.e.engine comprising of means for varying the trans5 mission of power between said adiabatic engines and the i.e.engine, means connecting such varying means to control means connected to to one <11, or more, means for sensing the i.e. engine* s exhaust gas condition and fuel flow varying means, and which incorporates at least one <11 of two (2) possible

IO throttle control system operating modes.
2) Means for controlling an i.e.engine according to claim 1, in which where there are one <11, or more adiabatic engines in the

i.e. engine’s intake system and one <11, or more, of them are

15 connected to the i.e.engine via variable power transmitting means and such varying means are connected to claim 1* s control means.
3) Means for controlling an i.e.engine according to claim 2, in

20 which there are means sensing the i.e. engine’s air, or chargeair, intake conditions connected to claim l’s control means.

·*·
4) Means for controlling an i.e. engine according to any of the * preceding claims, in which there are power transmitting means •J···; 25 connecting one <11, or more, controllable adiabatic engines to power accuaulating-discharging means, or power absorbing means, • ·· or both such means, and such power as is transmitted by said • ··* transmitting means is controlled by a brake control system and, or, claim l’s control means.

• 30
5) Means for controlling an i.e.engine according claim 4, in which there are limit controls limiting power transmission by , the power transmitting means.

»····« • ·

35
6) Means for controlling an i.e. engine according claim 4, in which there are controls limiting the continuation of power accumulation and power depletion.
7) Means for controlling an i.e.engine according to any of the

40 preceding claims, in which there are motorised exhaust flow shut-off means in the i.e.engine’s one ill, or more exhaust systems and the actuators of said shut-off means are connected to control means connected to means sensing exhaust conditions upstream of said flow shut-off means, and in which any fitted

45 catalytic convertors are preferably located upstream of said shut-off means.

81 Means for controlling an i.e.engine according to any of the preceding claims, in which there are bypassing means in the

50 i.e.engine’s one <11, or more, exhaust systems connecting said exhaust systems to the i.e.engine’s one <11, or more, intake systems and which incorporate motorised dampers whose actuators are connected to control means connected to temperature sensors

1 located upstream of said bypasses, and in which any fitted catalytic convertors are preferably located ustream of said bypasses.

5 9) Means for controlling an i.e. engine according to any of the preceding claims, in which there are means for bypassing exhaust gases around one <1), or more, of any adiabatic engines in the exhaust system connected to variable power transmitting in which there are motorised valves whose actuators are conn1O ected to control means connected to throttle position sensing means and, or, throttle rate-of-movement sensing means.
10) Means for controlling an i.e.engine according to any of the preceding claims, in which there are means for bypassing ex15 haust gases around one <1), or more, of any adiabatic engines connected to variable power transmitting means, and in which there are motorised valves whose actuators are connected to control means sensing conditions in the i.e.engine’s one <1), or more, intake systens downstream of adiabatic engines in said

20 intake systems.

·· • · r * * · • · · • « · • · · ···

I ft·

I * · ··· r •

>·«<·· • f

Intellectual

Property

Office

Application No: GB1713047.7 Examiner: Gareth Jones