EA043325B1 - METHOD FOR LIMITING ENGINE EMISSIONS - Google Patents

Description

Cross reference to related applications

This invention is claimed to have priority as of the filing date of U.S. Provisional Patent Application No. 63/091212, entitled Systems and Methods for a Locomotive Engine, filed October 2020. The entire contents of the foregoing application are incorporated herein by reference for all purposes.

Field of technology

Embodiments of the invention disclosed herein relate to internal combustion engines.

Discussion of the state of the art

Vehicles using combustion energy sources, such as internal combustion engines, can limit vehicle emissions (such as gases and particulate matter) and improve vehicle fuel efficiency. For some existing engines, operating them to control emissions and improve fuel efficiency may cause the engine to operate beyond hardware limitations. For example, engine operation may be limited by cylinder pressure. As another example, engine operation may be limited by the operating range of the engine's turbocharger compressor. For example, based on the operating range of an engine turbocharger compressor, the turbocharger may provide a limited amount of charge air during engine operation. Because vehicle emissions controls and improved fuel efficiency may require the engine to operate beyond hardware limitations, the potential for component performance degradation may increase and engine life may be reduced. In addition, poor fuel efficiency can increase the overall fuel cost of the engine, which can reduce customer satisfaction. As such, it may be desirable to have a system for controlling emissions and improving engine fuel efficiency that is different from systems currently available. The above problems are not recognized in the current state of the art.

The essence of the invention

In one embodiment, a method for controlling engine emissions includes adjusting the fuel injection timing of fuel injectors of an internal combustion engine relative to top dead center (TDC) in response to engine effective power input proportional to an engine governor position, whereby, as engine effective engine power input increases, an amount of advance is achieved. The fuel injection timing is decreased in a first range of engine governor positions and then increased in a second range of engine governor positions comprising larger engine governor positions than the first range.

Brief description of drawings

Fig. 1 is a schematic diagram of a vehicle with an engine in accordance with one embodiment of the present invention.

Fig. 2 depicts an exemplary graph of the relationship between engine governor positions and engine revolutions per minute (RPM) for an engine.

Fig. 3 depicts an exemplary graph of the relationship between engine governor positions and fuel injection timing for an engine.

Fig. 4 depicts an exemplary graph of the relationship between engine governor positions and line pressure for an engine fuel injection system.

Fig. 5 depicts an illustrative graph of the relationship between engine speed and engine line pressure limits.

Fig. 6 depicts an illustrative graph of the relationship between engine governor positions and fuel injection timing limits for an engine.

Fig. 7A depicts exemplary graphs of the relationship between barometric pressure, engine speed, and fuel injection timing for an engine.

Fig. 7B depicts exemplary graphs of the relationship between turbocharger inlet temperature, fuel injection speed, and fuel injection timing for an engine.

Fig. 7C depicts an exemplary graph of the relationship between engine altitude and engine cooling system performance.

Fig. 8 depicts an exemplary method for adjusting engine settings based on engine governor position adjustment.

Fig. 9 depicts an exemplary method of operating the engine.

Fig. 10 depicts an exemplary timeline for adjusting the motor governor position setting, including transient setting.

Detailed description

The following description relates to embodiments of a system/method for a vehicle having an internal combustion engine configured to control vehicle emissions and improve fuel efficiency. In one example, a vehicle system (eg, a railroad vehicle system) such as that shown in FIG. 1 may include an engine for burning an air-fuel mixture and may include a lubrication system for supplying engine oil to various components of the engine. To improve engine efficiency and reduce fuel consumption, the engine may include a common rail fuel system, a turbocharger with extended compressor operating range and advanced intake valve closing (IVC) timing. Fig. 2-7C depict calibrations for operation of the engine shown in FIG. 1, to increase the efficiency of the engine. In addition, FIG. 8 illustrates the method of operation of the engine, and FIG. 9 depicts a method for adjusting engine operation in response to a transient condition during a change in engine effective power input. In addition, FIG. 10 depicts an exemplary timeline for adjusting engine operating conditions during transient operation.

The approach described in this document can be used in various types of engines and in various engine-driven systems. For clarity of illustration, a rail vehicle such as a locomotive may be offered as an example of a mobile platform supporting a system comprising an embodiment of the invention. For example, the mobile platform may be a shunting locomotive with an engine, as described in detail below.

Fig. 1 shows an embodiment of a vehicle system. In particular, FIG. 1 depicts a block diagram of an embodiment of a vehicle system 100, depicted here as a locomotive vehicle 106, configured to move along a rail track 102 using wheels 112. As depicted, the locomotive includes an engine 104. The engine includes cylinders 101 (only one representative cylinder shown in FIG. 1), each of which includes at least one intake valve 103, at least one exhaust valve 105, and at least one fuel injector 107. Each fuel injector may include an actuator that may be actuated by a signal from controller 110 engine. In some examples, the intake valves and exhaust valves may be controlled by a camshaft that is configured to open and close the valves at predetermined times. For example, the rotation of the camshaft may be coupled to engine speed, and the camshaft may include lobe cams such that the cams open and close the intake and exhaust valves at predetermined engine positions. As an example, to reduce air flow to the cylinders and reduce temperature rise during the compression stroke, the intake valve closing timing may be set ahead of top dead center (TDC), for example, by adjusting the position of the intake valve cams and/or by adjusting the shape intake valve cams. In other examples, each inlet valve and each outlet valve may include an actuator that can be actuated by a signal from the controller. In other non-limiting embodiments, the engine may be a stationary engine, such as in a propulsion system, or a marine engine or other off-road vehicle propulsion system, as described above.

The engine receives intake air for combustion from an intake passage 114. The intake passage contains an air filter 160 that filters air entering from outside the locomotive. Exhaust gas generated by combustion in the engine is supplied to exhaust passage 116. For example, the exhaust passage may include an exhaust gas sensor 162 that may monitor the temperature and/or combustion products of the exhaust gas. The exhaust gas passes through the exhaust duct and exhaust system 170 of the locomotive. For example, the exhaust duct may be connected to a spark arrester to reduce sparks and/or carbon deposits in the exhaust, and a muffler to reduce unwanted exhaust noise.

The vehicle system may further comprise an aftertreatment system connected to the exhaust duct. In one embodiment, the aftertreatment system may include one or more emission control devices. Such emission control devices may contain a selective catalytic reduction (SCR) catalyst, a three-way catalyst, a NOx trap, or various other exhaust gas aftertreatment devices or systems. In another embodiment, the aftertreatment system may additionally or alternatively comprise an oxidation catalyst, such as a diesel oxidation catalyst (DOC) and a particulate filter (PF).

In addition, combustion in the cylinder(s) rotates a crankshaft (not shown). In one example, the engine is a diesel engine that burns air and diesel fuel by compression ignition. In another example, the engine is a dual-fuel or multi-fuel engine that can burn a mixture of gaseous fuel and air by injecting diesel fuel while compressing the air-gas fuel mixture. In other non-limiting embodiments, the engine may additionally or alternatively burn fuels including gasoline, hydrogen, ammonia, alcohol such as ethanol (EtOH) and/or methanol, kerosene, natural gas, biodiesel, or other petroleum distillates of similar density by ignition from compression (and/or spark ignition). Fuel can be liquid, gaseous and/or their combination

- 2 043325 bination.

As shown in FIG. 1, the engine is coupled to a power generation system that includes an alternator/generator 122. For example, the engine is a diesel engine and/or a natural gas engine that generates a torque output that is transmitted to the alternator/generator, i.e. mechanically coupled to the crankshaft as well as at least one of the wheels 112 to provide motive force for propulsion of the locomotive. The alternator/generator produces electrical energy that can be stored (eg in a battery) and/or used for distribution to a large number of downstream electrical components. In one example, the alternator/generator may be coupled to the electrical system 126. The electrical system may include one or more electrical loads configured to operate on electrical power generated by the alternator/generator, such as vehicle headlights, a cabin ventilation system, and an entertainment system, and may further comprise an energy storage device (eg, a battery) configured to be charged by electricity generated by the alternator/generator. In some examples, the vehicle may be a diesel-electric vehicle and the alternator/alternator may provide electricity to one or more electric motors to drive the wheels 112.

As shown in FIG. 1, the vehicle system further includes a cooling system 150 (eg, an engine cooling system). The cooling system circulates coolant through the engine to absorb waste heat from the engine and distribute the heated coolant to a heat exchanger such as radiator 152 (eg, a radiator heat exchanger). In one example, the coolant may be water, antifreeze, or a mixture thereof. In another example, the coolant may be oil. A fan 154 may be connected to the radiator to maintain air flow through the radiator when the vehicle is moving slowly or stopped while the engine is running. In some examples, the fan speed may be controlled by a controller. Coolant cooled by the radiator can enter the tank (not shown). The coolant may then be pumped back to the engine or other vehicle system component by pump 156.

The controller may be configured to control various components related to the locomotive vehicle system. For example, various vehicle system components may be connected to the controller via a communication channel or data bus. In one example, the controller includes a computer control system. The controller may additionally or alternatively comprise a storage device containing non-volatile computer readable storage media (not shown), including code for enabling on-board monitoring and control of locomotive operation. In some examples, the controller may comprise more than one controller, each of which communicates with each other, such as a first controller for controlling an engine and a second controller for controlling other vehicle operating parameters (such as engine load, engine speed, braking torque, and etc.). The first controller may be configured to control various actuators based on output data received from the second controller, and/or the second controller may be configured to control various actuators based on output data received from the first controller.

The controller can receive information from sensors and can send control signals to actuators. The controller, while monitoring the control and coordination of the engine and/or vehicle, may be configured to receive signals from various engine sensors, as further described herein, to determine operating parameters and operating conditions and accordingly adjust various engine actuators for control operation of the engine and/or vehicle. For example, the controller may receive signals from various engine sensors including, but not limited to, engine speed, engine load, manifold air pressure, boost pressure, exhaust gas pressure, ambient pressure, ambient temperature, exhaust gas temperature, temperature particulate filter, particulate filter inlet pressure or particulate filter pressure drop, engine coolant pressure, etc. Additional sensors, such as coolant temperature sensors, can be placed in the cooling system. Accordingly, the controller may control the engine and/or vehicle by sending commands to various components, such as one or more electric motors 124, an alternator/generator, fuel injectors, valves, a coolant pump, and the like. For example, the controller may control the operation of a restrictive element (eg, such as a valve) in an engine cooling system. Other actuators may also be connected to various locations in the vehicle.

In addition, the controller can monitor the effective motor power consumption for the motor governor. In an illustrative embodiment, the effective power consumption is

- 3 043325 engine may contain adjustment of the governor position or adjustment of the throttle valve. For example, the engine governor may respond to an adjustment of the engine governor position to regulate engine operation. For example, a vehicle operator can adjust the input device using engine governor position settings. Based on the selected engine governor position setting, the controller may adjust engine operation to provide desired engine characteristics (eg, such as desired vehicle speed). As an example, engine governor position settings may include position 0, position 1, position 2, position 3, position 4, position 5, position 6, position 7, and position 8. An increase in the governor position numeric value may correspond to an increase in vehicle speed and/or engine power output, as well as adjustments to fuel injection timing and line pressure. For example, position 0 could be the locomotive not moving, position 4 could be a medium speed setting, and position 8 could be a maximum speed setting. For example, the controller may adjust engine revolutions per minute (RPM), gearing, valve timing, and other parameters to move the vehicle at a speed corresponding to the selected engine governor position. For example, the engine may be adjusted to produce more power to increase vehicle speed or to handle a heavy load (eg, load and/or grade).

Additionally, the vehicle can limit emissions and improve fuel efficiency. For example, existing diesel locomotive engines may contain a pump injector that can link injection pressure to engine speed and camshaft timing. In addition, such an engine system may include intake and exhaust cam profiles with optimized volumetric efficiency, which may be designed to ensure that as much air as possible can be entrained into the cylinder for the compression stroke. In addition, the turbocharger found in existing diesel locomotive engines may have a limited operating range. Operating such a system (e.g., a diesel locomotive incorporating pump injector, volumetric efficiency, and a limited operating range) to control emissions and improve fuel efficiency may result in operation beyond the mechanical limits of the engine components and may also result in relatively low efficiency at working within mechanical limits. For example, operating an engine beyond the hardware limits of the engine components can increase the likelihood of component degradation and increase maintenance costs.

To limit emissions and improve fuel efficiency without exceeding the engine's mechanical limitations, the inventors here have implemented several features that can synergistically combine to reduce vehicle emissions and improve vehicle efficiency. Firstly, instead of an injection pump, the engine may contain a fuel system with a common injection pipe, i.e. high pressure fuel pump with fuel lines with a common discharge line and with an appropriately sized discharge line volume leading to the electronically controlled injectors. Using a common rail fuel system can improve fuel atomization during injection and can reduce particulate matter (PM) formation. In addition, the use of a common rail fuel system separates injection pressure and timing from engine speed and/or valve timing, thereby optimizing the trade-off between nitrogen oxide (NOx), particulate matter (PM) and specific fuel consumption ( SFC) while remaining within the mechanical limits of the engine. Second, intake valve timing can be set to advance bottom dead center (BDC) (i.e., advance Miller cycle) to reduce air flow into the cylinder while reducing temperature rise during the compression stroke. For example, intake valve closure (IVC) may occur earlier. Adjusting the intake valve timing as described can reduce NOx formation during combustion. In particular, intake valve timing may be advanced relative to BDC (eg, offset from BDC to reduce the effective compression ratio). Third, the turbocharger may include an optimized compressor wheel, diffuser and nozzle ring to improve the efficiency of the turbocharger. Taken together, these turbocharger settings can extend the operating range of the compressor. For example, an extended turbocharger compressor operating range increases the turbocharger's surge margin. Additionally, particulate generation can be reduced while the mechanical limitations of the turbocharger can be increased to increase the engine's operating range.

The three features described above (i.e., common rail fuel system inclusion, advanced intake valve closing, and extended operating range turbocharger) can be advantageously combined to reduce vehicle emissions while improving vehicle fuel efficiency. In addition, combining the three functions may provide additional benefits over those provided by each function separately. For example, decreasing

- 4 043325

NOx can be achieved primarily by controlling the volumetric efficiency of the airflow and reducing the effective compression ratio of the engine cylinders by advancing the closing of the intake valves. However, this change in airflow can increase the amount of boost required from the turbocharger. For example, without enabling an extended-range turbocharger as described above, pre-closing intake valves may result in poor component performance and may impair overall engine performance. To reduce the likelihood of such component degradation, the turbocharger is preferably driven (eg, by an extended-range turbocharger) to synergistically reduce vehicle emissions. In addition, a decrease in volumetric efficiency (for example, as a result of advanced closing of the intake valves) can reduce the airflow for a given boost level at all engine governor positions. For example, reducing the air flow in the middle positions of the regulator can reduce the quality of combustion in systems with a pump injector system. Thus, without incorporating a common rail fuel system, the benefits to engine efficiency and emissions may be outweighed by the reduction in engine performance. Thus, incorporating a common rail fuel system can synergistically address combustion quality issues such that the volumetric efficiency reduction benefits of advanced IVC (e.g., reduced vehicle emissions) can be maintained without reducing combustion efficiency or reducing combustion quality resulting in increased emissions of individual substances. For example, both fuel injection pressure and fuel injection timing can be calibrated for each engine governor position to advantageously reduce vehicle emissions and improve vehicle efficiency. In general, the three diesel engine system adjustments described above can interact synergistically such that the combination of the three adjustments provides a greater benefit than each of the three adjustments could provide individually, so that engine efficiency is increased, emissions are reduced, fuel consumption is reduced, and performance engine operation is maintained.

To provide these benefits at any effective engine power input, different engine operating conditions can be calibrated for each effective engine power input to keep vehicle emissions low and fuel efficiency high. In an exemplary embodiment, engine operating conditions may be calibrated each time the governor position is adjusted. In particular, in FIG. Figure 2-7B shows engine calibrations over a range of engine system operating conditions, including common rail fuel system, advanced IVC, and extended operating range for the turbocharger.

Let us now turn to FIG. 2, graph 200 depicts an example of the relationship between engine governor positions and engine revolutions per minute (RPM). For example, the exemplary relationship in graph 200 may correspond to a prescription of governor positions for engine speeds based on a selected engine governor position. The target engine speed for each engine governor position is shown by crosses 202. For the above, the vertical axis depicts the relative engine speed per minute, with the target engine speed increasing along the vertical axis from bottom to top. The horizontal axis depicts the motor governor positions, with the engine governor positions increasing along the horizontal axis from left to right. As shown, the target engine RPM (crosses 202) may increase with engine governor positions such that the target engine RPM continuously increases in proportion to the engine governor position setting. In other words, the relationship between the target engine speed and the engine governor position setting can be described by a monotonic function. For example, the calibration contains higher RPM setpoints for higher governor positions to increase the amount of airflow through the engine and avoid running the turbocharger beyond the surge limit, increase bearing oil film thickness, and increase peak cylinder ignition pressure. Additionally, higher RPM targets at higher governor positions can increase engine ventilation since the electrical frequency of the auxiliary alternator can be locked to engine RPM. Increased airflow can also provide the ability to inject more fuel and increase torque/power. Increasing engine ventilation can reduce engine temperatures at higher governor positions, which can reduce the likelihood of component degradation.

Next, in FIG. 3, graph 300 depicts an example of the relationship between engine governor positions and fuel injection timing. For example, graph 300 shows the calibration of fuel injection timing for each engine governor position to reduce vehicle emissions while improving fuel efficiency. The target fuel injection timing for each engine governor position is shown by crosses 302. For the above, the vertical axis depicts the relative fuel injection timing, with the target fuel injection timing increasing up the vertical axis from bottom to top. The horizontal axis depicts the position of the regulator

- 5 043325 engine, with positions increasing along the horizontal axis from left to right. As shown, small governor positions (e.g., position 2 and below) may contain less advanced target fuel injection timing because fuel consumption can vary widely in this area, which may only minimally affect emissions and fuel consumption. In position 3 and position 4, the target fuel injection timing can be even less advanced, with less advanced timing reducing peak combustion temperatures, which result in lower NOx emissions. In addition, as power increases (e.g. position 5 and above), fuel consumption can be reduced thanks to advanced torques to reduce fuel consumption as much as possible. For example, the advance amount decreases continuously between position 1 and position 4 and increases continuously between position 4 and position 8. For example, the relationship between the advance amount and the engine governor position setting is non-monotonic. Additionally, in some examples, higher engine speed, lower power operating conditions may include more advanced target fuel injection timing to reduce hydrocarbon emissions while maintaining combustion stability.

Next, in FIG. 4, graph 400 depicts an example of the relationship between engine governor positions and line pressure (eg, fuel injection line pressure). The target line pressure for each engine governor position is shown by crosses 402. For the above, the vertical axis depicts the relative line pressure, with the target line pressure increasing upward along the vertical axis from bottom to top. The horizontal axis shows the engine governor positions increasing along the horizontal axis from left to right. As shown, small positions (eg, less than position 3) may correspond to a lower target line pressure due to changes in fuel flow in that area. For example, lower control positions may correspond to low power operation. In addition, the target main pressure is increased for position 3 and position 4 to limit/reduce PM. For example, in position 3 and position 4, boost can be applied/implemented during engine operation when a relatively low air-fuel ratio (AFR) is required. In general, line pressure may increase continuously (eg, increase monotonically) in response to increasing engine governor position adjustment. Medium line pressure may be required to achieve low AFR, and higher injection pressure may control PM and may improve thermodynamic efficiency.

Next, in FIG. 5, graph 500 depicts an example of the relationship between engine speed and line pressure limit. For example, although the target line pressure calibration was shown in FIG. 4 Based on the selected engine governor position, other engine operating conditions, such as engine speed, may cause the controller to adjust line pressure to maintain engine operation. The line pressure limit is shown by the dashed graph 502. For the above, the vertical axis depicts the line pressure limit, with the line pressure limit increasing upward along the vertical axis from bottom to top. The horizontal axis depicts the increase in engine speed along the horizontal axis from left to right. As shown, up to 580 rpm the main line pressure is limited to 1000 bar due to the mechanical limitations of the high pressure fuel pump. For example, up to 580 rpm the main pressure cannot exceed 1000 bar. Additionally, above 580 rpm the system is limited to 1600 bar due to the mechanical limitations of the high pressure fuel pump and fuel injector. For example, above 580 rpm the main pressure can rise to 1600 bar.

Next, in FIG. 6, graph 600 depicts an example of the relationship between engine governor positions and fuel injection timing limits. For example, although target fuel injection timings are shown in FIG. 3, the fuel injection timing can be adjusted based on the target fuel injection time based on various engine operating conditions such as engine temperature and engine power. The relationship shown in Graph 600 demonstrates the maximum and minimum restrictions on the timing of fuel injection depending on the positions of the engine governor. The upper limit of the fuel injection timing is shown by the dashed graph 602, and the lower limit of the fuel injection timing is shown by the dashed graph 604. For the above, the vertical axis depicts the relative fuel injection timing, and the relative limit of the fuel injection timing increases along the vertical axis from bottom to top. The horizontal axis shows the engine governor positions increasing along the horizontal axis from left to right. Minimum fuel injection timing can be increased (e.g., advanced) by governor positions, so that minimum fuel injection timing is higher at high governor positions and lower at low governor positions. For example, fewer engine physical constraints are present at lower governor positions, while more engine physical constraints are present at higher positions (eg, such as turbocharger speed, peak cylinder pressure, and fuel injection duration).

Fig. 7A depicts an exemplary graph 700 of the relationship between atmospheric pressure and engine operating conditions, including engine speed and fuel injection timing. Frequency

- 6 043325 engine rotation at position 5 is shown by graph 702, engine speed at position 3 is shown by graph 704, and engine speed at position 1 is shown by graph 706. In addition, the timing of fuel injection at position 3 is shown by graph 712, the timing of fuel injection at position 4 is shown in graph 710, fuel injection timing in position 5 is shown in graph 708, fuel injection timing in position 6 is shown in graph 718, fuel injection timing in position 7 is shown in graph 716, and fuel injection timing in position 8 is shown in graph 714. For all of the above the horizontal axis depicts atmospheric pressure increasing along the horizontal axis from left to right. The vertical axis represents each labeled parameter. For each of plots 702, 704, 706, 708, 710, 712, 714, 716, and 718, the parameter value increases upward along the vertical axis. Specifically, for each of plots 708, 710, 712, 714, 716, and 718, fuel injection timing is more advanced as it moves up the vertical axis. For example, a vehicle may operate in different atmospheric conditions, so the barometric pressure changes. Changes in barometric pressure can affect engine operating conditions and in particular can affect intake air quality, such as air flow into the engine due to changes in pressure/density. Higher barometric pressure can increase density, which can result in increased mass flow into the engine. As such, engine parameters such as engine speed and fuel injection timing can be adjusted based on atmospheric pressure.

As shown in FIG. 7A, each of position 5 engine speed (plot 702), position 3 engine speed (plot 704), and position 1 engine speed (plot 706) decreases as barometric pressure increases. For example, the engine speed at each of positions 5, 3, and 1 is higher at low barometric pressures, which can increase the oxygen-to-fuel ratio in the engine cylinders and promote mixing. Note that the trend shown by graphs 702, 704 and 706 may be similar for position 2 and position 4, which are not shown. This can counteract soot formation caused by the reduced oxygen content of the intake air at low barometric pressure. Moreover, as shown in FIG. 7A, each of the fuel injection timing at position 3, the fuel injection timing at position 4, and the fuel injection timing at position 5 may be less advanced as the barometric pressure increases and may be more advanced as the barometric pressure decreases. For example, the average engine governor position settings, such as position 3, position 4, and position 5, may be less advanced as barometric pressure increases. For example, fuel injection timing for positions 3, 4 and 5 can be advanced at lower barometric pressures, which can improve emissions opacity and reduce exhaust particulate emissions. Moreover, as shown in FIG. 7A, fuel injection timing for positions 6, 7, and 8 (eg, high engine governor position settings) may be more advanced as barometric pressure increases and may be less advanced as barometric pressure decreases. For example, less advanced fuel injection timing at low barometric pressure can reduce NOx emissions.

Fig. 7B depicts an exemplary graph 750 of the relationship between turbocharger inlet temperature (ie, compressor inlet temperature correlated with ambient temperature) and engine operating conditions, including engine speed and fuel injection timing. Engine speed at position 5 is shown by graph 720, engine speed at position 3 is shown by graph 722, and engine speed at position 1 is shown by graph 724. Note that engine speed trends may be similar for position 4 and position 2, which not shown. In addition, the fuel injection timing at position 6 is shown by graph 726, the fuel injection timing at position 5 is shown by graph 728, and the fuel injection timing at position 4 is shown by graph 730. For all of the above, the horizontal axis depicts the increase in temperature at the turbocharger inlet on the horizontal axis on the left right. The vertical axis depicts each labeled parameter. For each of plots 720, 722, 724, 726, 728 and 730, the parameter value increases upward along the vertical axis. For example, the turbocharger inlet temperature can also influence engine operating conditions, for example by changing the engine air temperature. As shown, at turbocharger inlet temperatures below 100°F (38°C), engine speed may be constant at each level shown. Specifically, the speed at position 1 (graph 724) is constant below 100°F (38°C), the speed at position 3 (graph 722) is constant below 100°F (38°C), and the speed at position 5 ( chart 720) is constant below 100°F (38°C). After the turbocharger inlet temperature exceeds 100°F (38°C), position 1 speed (graph 724), position 3 speed (graph 722), and position 5 speed (graph 720) may each increase. In addition, the relationship between fuel injection timing and turbocharger inlet temperature is shown. As shown, as the turbocharger inlet temperature increases, the fuel injection timing can be adjusted to less advanced timing. For example, the relationship between fuel injection timing and turbocharger temperature may be approximately inversely proportional.

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Next, in FIG. 7C shows a graph 775 of an exemplary relationship between engine altitude and engine cooling system performance (eg, cooling system performance). Cooling system performance is shown in graph 732. For example, cooling system performance may reflect the net effect of the cooling system. The performance of the cooling system can be adjusted by adjusting the coolant temperature, coolant pressure, radiator speed, etc. For the above, the horizontal axis depicts the increase in altitude along the horizontal axis from left to right. The vertical axis represents the labeled parameter. For graph 732, the parameter value increases upward along the vertical axis. For example, altitude can also affect engine operating conditions. In particular, engine cooling system performance (e.g., cooling system capacity) may be affected by altitude or atmospheric pressure and ambient temperature. As shown, the efficiency of the cooling system 732 decreases with altitude. Lower barometric pressure (high altitude) can reduce cooling system performance due to loss of air density used in convective cooling with radiators. As altitude and ambient temperature increase, the radiator and engine fan speeds may increase to try to maintain engine water temperature. Engine water can be used to cool the engine oil and manifold air temperature. In severe environmental conditions, when the fans and engine may be running at maximum speed, the engine power may be reduced to maintain the required oil temperatures.

Next, FIG. 8 illustrates a method 800 of operating an engine, such as the engine described with reference to FIG. 1. For example, an engine system may comprise a common rail fuel system, an advanced intake valve closing (IVC) timing, and an extended operating range turbocharger (eg, an extended operating range compressor turbocharger). In particular, these elements can be advantageously combined to improve the fuel efficiency of the engine. The method 800 will be described in relation to the locomotive 106 shown in FIG. 1, and with the calibration shown in FIG. 2-7C, although method 800 may be used in other systems. Instructions for performing method 800 and the remaining methods included herein may be executed by the controller based on instructions stored in the controller's memory and in combination with signals received from vehicle system sensors, such as the sensors described with reference to FIG. 1. The controller may use vehicle system actuators to adjust engine operation in accordance with the methods described below.

At step 802, method 800 includes forcing intake air using a boost mechanism (eg, a turbocharger), the operating range of the turbocharger providing reduced vehicle emissions and increased vehicle efficiency. For example, air may enter the engine system through the intake manifold. However, air can be forced through a turbocharger to increase pressure. For example, the compressor portion of a turbocharger may provide compressed air.

At step 804, method 800 includes injecting air into the engine cylinders. For example, intake air after being pressurized by the turbocharger at step 802 may be introduced into the engine cylinders. For example, each engine cylinder may include at least one intake valve. The actuator can adjust the position of the intake valves so that air can enter the cylinders. For example, the opening timing of the intake valve can be adjusted depending on engine operating conditions.

At step 806, method 800 includes adjusting the effective compression ratio of the cylinders by adjusting intake valve closing (IVC) timing. For example, by setting the IVC torque early, the effective compression ratio of the cylinders can be reduced. In this way, the volumetric efficiency of the engine can be controlled.

At step 808, method 800 includes injecting fuel into engine cylinders through a common rail fuel system. For example, a common rail fuel system can inject fuel into each cylinder at the same pressure and can be controlled independently of engine speed so that fuel injection timing can be adjusted without adjusting engine speed. For example, fuel injection timing may increase or decrease depending on the position of the engine governor and other engine operating conditions. For example, the controller may adjust a signal to one or more fuel injectors to adjust the timing of fuel injection.

At step 810, method 800 includes burning the air-fuel mixture in the cylinders. For example, air and fuel in each of the cylinders can be burned to produce energy. In addition, combustion can produce hot exhaust gas, which can exit the cylinders through the exhaust valves.

At step 812, method 800 includes extracting energy from combustion exhaust gas to gain

- 8 043325 activates the pressurization mechanism (nozzle ring). For example, a turbocharger includes a nozzle ring on the turbocharger turbine. The nozzle ring directs the exhaust gases to convert the exhaust gases into kinetic energy; thus energy is extracted by the turbine. In particular, the energy extracted by the turbine from the exhaust gas can be used to power the turbocharger compressor. For example, the energy extracted by a turbine can drive the compressor shaft of a turbocharger. In this way, the hot exhaust gas produced by combustion can in turn be used to supercharge the air drawn into the cylinders. As another example, a nozzle ring (on a turbocharger turbine) may direct exhaust flow into a turbine wheel, with the turbine extracting energy, and the nozzle ring may control exhaust velocity into the turbine and inlet pressure.

At step 814, method 800 optionally includes adjusting at least one of fuel injection timing, rail pressure, and intake valve closing timing. For example, depending on engine operating conditions, including engine governor position, engine speed, turbocharger inlet temperature, barometric pressure, and other conditions, one or more of fuel injection timing, rail pressure, and IVC timing can be adjusted to increase engine efficiency and reduce fuel consumption. In particular, to reduce emissions and improve efficiency, at least one of fuel injection timing, line pressure and IVC timing can be adjusted in accordance with the calibrations shown in FIG. 2-7V.

In this way, the engine system can provide energy to the vehicle while simultaneously increasing efficiency, reducing fuel consumption, and reducing vehicle emissions. Overall, customer satisfaction can be increased. For example, through the advantageous combination of an advanced charging mechanism, advanced IVC and a common rail fuel system, engine performance can be increased while fuel consumption and vehicle emissions are reduced.

In addition to the calibrations for each engine governor position shown in FIG. 2-7C, the engine may include calibrations for transient operation, such as when the engine switches between effective power inputs. For example, when a motor is switched between positions by the motor governors, it may enter a transition state until the transition is completed. In particular, when an upward transition occurs upon throttle activation (eg, a transition occurs from a lower engine governor position to a higher engine governor position), the transition state may contain calibrations to increase the engine's response to load.

Thus, FIG. 9 illustrates a method 900 of operating an engine to transition from a first effective engine power input to a second effective engine power input. In an exemplary embodiment, the method may control the engine to transition between governor position settings or throttle valve settings. For example, during a transition between a first engine governor position and a second engine governor position, where the second position is higher than the first position, the engine may enter a transition state. Thus, when the engine moves up in position when the throttle valve is activated, the engine enters a transient state that includes transient calibration for engine operating conditions such as fuel injection timing, line pressure, and reference engine speed. For example, the engine speed reference is the target engine speed. In particular, to increase engine load response, line pressure may be increased, fuel injection timing may be increased, and engine reference speed may be increased relative to steady state operation (e.g., steady state operation as in the first position of the engine governor, and in the second position of the engine governor). The method 900 can be described in relation to the locomotive 106 shown in FIG. 1, although method 900 may be used in other systems. Instructions for performing method 900 may be executed by the controller based on instructions stored in the controller's memory and in combination with signals received from vehicle system sensors, such as the sensors described with reference to FIG. 1. The controller may use vehicle system actuators to adjust engine operation in accordance with the methods described below.

At step 902, method 900 includes estimating and/or measuring operating conditions. Operating conditions may include, for example, vehicle speed, engine speed, engine load, engine governor position, engine temperature, turbocharger inlet temperature, atmospheric pressure, and the like. For example, the controller may determine the engine governor position based on the throttle position. As another example, the turbocharger inlet temperature may be measured by a temperature sensor located adjacent to the turbocharger inlet. As another example, barometric pressure may be determined based on a pressure sensor outside the engine. As another example, engine speed may be determined based on a crankshaft position sensor.

- 9 043325

At step 904, method 900 includes determining whether a change in knob position is requested. For example, the controller may determine whether the user has adjusted the engine governor position, such as by adjusting the throttle position. For example, the controller may monitor throttle position through a throttle position sensor. In particular, the controller may determine the position of the engine governor based on the throttle position.

If method 900 determines, at block 904, that a change in knob position is not requested, method 900 proceeds to block 908, as will be described in detail below. For example, if the controller determines that the throttle position has not been adjusted to a different engine governor position, method 900 proceeds to block 908.

If method 900 determines, at block 904, that a change in governor position is requested, method 900 proceeds to block 906 and includes adjusting the engine parameters for transient operation. For example, if the controller determines that a governor position change is a transition from a first position to a second position, and the second position is a higher position relative to the first position, the line pressure may be increased, fuel injection timing may be advanced, and the engine speed reference may be advanced. may be increased. In other words, when a governor position change is requested, and the governor position change is to a higher position (eg, the engine moves up in position when the throttle is activated), method 904 includes adjusting engine settings for transient operation by increasing the engine's response to load. To increase the engine's response to load, the main pressure is increased relative to the main pressure in each of the first and second positions, the fuel injection timing is set ahead of each of the first and second positions, the fuel injection duration is increased relative to the first position of the regulator, and the reference engine speed is increased. relative to each of the first and second positions. If the second position of the engine governor is lower than the first position, then the transient calibration may not include increasing the line pressure, setting the fuel injection timing ahead and increasing the reference engine speed. For example, transient calibration may involve not adjusting engine settings to increase engine response to load.

At step 908, method 900 includes determining calibrations for the desired adjustment of the control position. For example, calibrations for a desired control position setting may be determined based on a set of calibration tables such as those shown in FIG. 2-7C. For example, based on the position of the engine governor, a target rail pressure, a target fuel injection timing, a target engine speed, a rail pressure limit, and a fuel injection timing limit may be selected. In addition, engine settings can be further adjusted depending on environmental conditions (such as atmospheric pressure, for example).

At step 910, method 900 includes adjusting engine operation to the desired settings for the desired governor position. For example, the controller may regulate engine actuators to regulate one or more of line pressure, fuel injection timing, engine speed, and the like. For example, at step 910, the engine is operated at the desired position. After this, execution of method 900 may end.

Next, in FIG. 10 shows an example of how time scale 1000 can be used to operate an engine. For example, as described with respect to method 900 in FIG. 9, when the engine switches between consumed effective engine power, the engine enters a transition state, for example, between governor positions. In addition, since the second engine governor position is higher than the first engine governor position, the transition state includes increasing the engine reference speed, increasing the fuel line pressure, and setting the fuel injection timing to advance to increase the engine response to load. Engine governor position setting is shown in graph 1002, line pressure for the fuel injection system is shown in graph 1004, fuel injection timing is shown in graph 1006, and engine speed reference is shown in graph 1008. For all of the above, the horizontal axis represents time, with time increases along the horizontal axis from left to right. The vertical axis depicts each marked parameter. For each of the graphs 1004, 1006 and 1008, the parameter value increases upward along the vertical axis. For graph 1002, the vertical axis depicts whether the engine is running in position 4 (4), in position 5 (5), or in a transition state between position 4 and position 5 (t).

Between time t0 and time t1, the motor is set to position 4 (graph 1002). Accordingly, line pressure (graph 1004), fuel injection timing (graph 1006) and reference engine speed (graph 1008) can be set based on predefined calibration tables for governor position 4. For example, as shown, line pressure, fuel injection timing and the reference engine speed at position 4 are relatively small.

At time t1, the controller position setting enters a transition state. In particular,

- 10 043325 A transition state occurs when the motor switches between two governor positions. In addition, the engine can shift to a higher position, so that the engine moves up in position when the throttle is activated. To improve the engine's response to load, the main pressure (graph 1004), fuel injection timing (graph 1006) and reference engine speed (graph 1008) are adjusted. As shown, line pressure (plot 1004) increases relative to line pressure until time t1, fuel injection timing (plot 1006) increases relative to line pressure until time t1, and reference engine speed (plot 1008) increases relative to reference engine speed until moment of time t1. Between time t1 and time t2, when the engine is in a transition state between governor positions, each of the line pressure, fuel injection timing, and reference engine speed remains constant.

At time t2, the engine exits the transient state and enters operating mode at position 5. For example, governor position 5 represents a higher power setting than governor position 4, so that each of the line pressure (graph 1004), fuel injection timing ( graph 1006) and reference engine speed (graph 1008) increases compared to operation in position 4. However, each of the main pressure (graph 1004), fuel injection timing (graph 1006) and reference engine speed (graph 1008) is lower in position 5 regarding operation in a transition state (for example, between time t1 and time t2).

Between time t2 and time t3, the engine remains in position 5, while each of the main pressure (graph 1004), fuel injection timing (graph 1006) and reference engine speed (graph 1008) remains constant and higher in level than at operating in position 4 (for example, between time t0 and time t1), and lower in level than when operating in a transition state (for example, between time t1 and time t2).

Thus, as shown in FIG. 10, when the engine moves from the first governor position setting (for example, position 4) to the second, higher governor position setting (for example, position 5), the engine enters a transition state, with each of line pressure, fuel injection timing, and reference frequency engine rotation is higher in the transition state than when setting the first position of the regulator or the second, higher position of the regulator. Increasing the line pressure, fuel injection timing, and reference engine speed can increase the engine's load capacity, which can improve the vehicle's fuel efficiency.

In this way, a vehicle's diesel locomotive engine system can operate with reduced vehicle emissions while simultaneously increasing fuel efficiency. Specifically, the engine can operate with an extended-range turbocharger, a common rail fuel system, and advanced intake valve closure to reduce air flow into the engine cylinders. These three functions can be synergistically combined to reduce vehicle emissions such as NOx and PM while improving fuel efficiency throughout the engine's operating range. For example, in an engine system with these characteristics, engine speed, line pressure, fuel injection timing, line pressure limit, fuel injection timing limit, and other engine parameters can be calibrated for each engine governor position. Engine parameters can be further calibrated based on environmental conditions such as barometric pressure, turbocharger inlet temperature, and altitude. Overall, vehicle emissions can be reduced and fuel efficiency can be increased. For example, reduced vehicle emissions and increased fuel efficiency can enable a diesel locomotive system to meet environmental regulations without operating the engine beyond the engine's mechanical limits. Thus, the likelihood of component degradation may increase. In addition, by improving the fuel efficiency of the vehicle, the cost of operating the vehicle can be reduced. For example, when a vehicle operates with increased fuel efficiency, less fuel is required to travel the same distance, so overall fuel costs are reduced.

The technical result of incorporating a common rail fuel system, a turbocharger and an advance IVC into the engine system of a locomotive system is that the volumetric efficiency of the cylinders is reduced while emissions are reduced and fuel efficiency is increased.

The invention also provides a method including adjusting the amount of advance of the fuel injection timing of fuel injectors of a diesel internal combustion engine relative to top dead center (TDC) depending on the position of the engine governor, and as the position of the engine governor increases, the amount of advance is first reduced and then increased.

In the first example of the method, the method further includes adjusting the upper limit to increase the amount of advance of the fuel injection timing of the fuel injectors relative to TDC in advance

- 11 043325 depending on the position of the engine governor, and when the position of the engine governor increases, the upper limit for increasing the amount of advance of the fuel injectors relative to TDC is reduced, and the adjustment of the lower limit to reduce the amount of advance of the fuel injection timing of the fuel injectors relative to TDC depending on the position of the engine governor , and when the position of the engine governor increases, the lower limit for reducing the amount of advance of the fuel injection timing for the fuel injectors relative to TDC is increased.

In a second example of the method, optionally including the first example, the method further includes: adjusting the number of engine revolutions per minute (RPM) depending on the position of the engine governor, wherein as the position of the engine governor increases, the number of engine revolutions is increased.

In a third example of the method, optionally including one or both of the first and second examples, the method further includes adjusting the main pressure in the common rail fuel injection system of the diesel internal combustion engine depending on the position of the engine governor, wherein, as the position of the engine governor increases, The main pressure of the fuel injection system with a common discharge pipeline is increased.

In a fourth example of a method, optionally including one or more or each of the first through third examples, the method further includes, in response to a transition from a first motor governor position to a second engine governor position, wherein the second engine governor position is higher than the first engine governor position, increasing main pressure of the fuel injection system with a common discharge pipeline and reference engine speed.

In a fifth example of the method, optionally including one or more of the first through fourth examples, the method further includes, in response to a diesel internal combustion engine turbocharger inlet temperature exceeding 100°F (38°C), increasing engine speed and reducing fuel injection timing advance. injectors relative to TDC as the temperature at the turbocharger inlet increases.

In the sixth method example, optionally including one or more or each of the first to fifth examples, the engine governor position is determined based on the user input state for selecting the desired governor position for the diesel internal combustion engine governor.

The invention also provides an engine system comprising cylinders, an engine governor with engine governor position settings, a common rail fuel injection system, the common rail fuel injection system comprising fuel injectors coupled to the cylinders, a turbocharger comprising a nozzle ring on a turbocharger turbine, a camshaft configured to advance the closing timing of the intake valve, a controller containing executable instructions stored in non-volatile memory which, when executed, cause the controller to respond to an increase in the engine governor position setting from a first level to a second level higher than the first level , reduces the amount of advance of the fuel injection timing of the fuel injectors relative to top dead center (TDC) and in response to an additional increase in the engine governor position setting from the second level to the third level, which is higher than the second level, increases the amount of advance of the fuel injection timing of the fuel injectors relative to TDC.

In the first example system, the controller contains additional executable instructions stored in non-volatile memory that, when executed, cause the controller to: decrease the upper limit to increase the amount of fuel injection timing advance for the fuel injectors relative to TDC as the engine governor position setting is increased from the first level to the second level, and increases the lower limit to reduce the amount of advance of the fuel injection timing of the fuel injectors relative to TDC as the engine governor position setting increases from the first level to the second level.

In a second example system, not necessarily including the first example, the controller contains additional executable instructions stored in non-volatile memory that, when executed, cause the controller to: in response to adjusting the engine governor position, increase from a first level to a second level, increase engine speed per minute (RPM).

In a third example of a system, optionally including one or both of the first and second examples, the controller includes additional executable instructions stored in non-volatile memory that, when executed, cause the controller to respond to increasing the motor governor position setting from the first level to the second level increases the main pressure of the fuel injection system with a common discharge pipeline.

In a fourth example system, optionally including one or more of examples one through three, the controller includes additional executable instructions stored in nonvolatile memory that, when executed, cause the controller to limit line pressure in response to engine speeds of 580 rpm or below. common rail fuel injection systems up to 1000 bar or lower and in response to engine speeds above

- 12 043325

580 rpm limits the main fuel injection system pressure at or below 1600 bar.

In a fifth example system, optionally including one or more or each of the first through fourth examples, the controller includes additional executable instructions stored in nonvolatile memory that, when executed, cause the controller to respond to a transition state during the transition from adjusting the first engine governor position to adjusting the second engine governor position, wherein adjusting the second engine governor position higher than the first engine governor position setting increases both the main line pressure in the common rail fuel injection system and the reference engine speed.

In a sixth example system, optionally including one or more or each of examples one through five, the controller contains additional instructions stored in nonvolatile memory that, when executed, cause the controller to reduce engine speed in response to increased atmospheric pressure in the engine system, and in response to an increase in atmospheric pressure and setting the engine governor position to the middle position of the engine governor, it reduces the amount of advance of the fuel injection timing relative to TDC, and in response to an increase in barometric pressure and setting the engine governor position to a high position, the engine governor sets the advance torque fuel injection relative to TDC.

In a seventh example system, optionally including one, or more, or each of the first through sixth examples, the controller contains additional instructions stored in non-volatile memory that, when executed, cause the controller to respond to a turbocharger inlet temperature greater than 100° F (38°C) increases engine speed and reduces the advance of fuel injection timing relative to TDC as the temperature at the turbocharger inlet increases.

The invention also provides a system comprising a diesel engine comprising cylinders, an engine governor with engine governor position settings, a common rail fuel injection system, the common rail fuel injection system comprising fuel injectors coupled to the cylinders, a turbocharger comprising an injector ring, a camshaft configured for extended intake valve closing time, a controller containing executable instructions stored in non-volatile memory which, when executed, cause the controller, in response to engine governor position settings, to adjust the amount of advance of the fuel injection timing of the fuel injectors relative to top dead center (TDC) based on the first non-monotonic relationship between the engine governor position setting and the fuel injection timing.

In the first example of a system for adjusting the amount of advance of the fuel injection timing of fuel injectors relative to TDC based on a non-monotonic relationship between setting the position of the engine governor and the timing of fuel injection, the controller additionally contains instructions stored in non-volatile memory, which, when executed, cause the controller to respond to increasing the engine governor position setting from the first level to a second level, which is higher than the first level, reduces the amount of advance of the fuel injection timing of the fuel injectors relative to TDC and in response to a further increase in the engine governor position setting from the second level to the third level, which is higher than the second level increases the amount of advance of the fuel injection timing of the fuel injectors relative to TDC.

In a second example of a system, optionally including the first example, the controller contains additional instructions stored in non-volatile memory that, when executed, cause the controller to reduce the upper limit to increase the amount of advance of the fuel injection timing of the fuel injectors relative to TDC as the position is set the engine governor increases, and increases the lower limit to reduce the amount of advance of the fuel injection timing of the fuel injectors relative to TDC when the engine governor position setting is decreased.

In a third example of a system, optionally including one or both of the first and second examples, the controller includes additional instructions stored in non-volatile memory that, when executed, cause the controller to adjust the engine's revolutions per minute (RPM) in response to adjusting the engine governor position. ) based on a monotonic relationship between the engine governor position setting and engine speed.

In a fourth example system, optionally including one or more of examples one through three, the controller includes additional instructions stored in non-volatile memory that, when executed, cause the controller to, in response to atmospheric pressure, adjust the amount of fuel injection timing advance of the fuel injectors relative to TDC. based on the second non-monotonic relationship between setting the position of the engine governor and the timing of fuel injection.

When used herein, an element or step set forth in the singular is to be understood as not excluding the plurality of said elements or steps, unless

Claims (4)

However, such an exception is not explicitly stated. In addition, references to one embodiment of the invention do not preclude the existence of additional embodiments that also include the listed features. Moreover, unless explicitly stated otherwise, embodiments containing, including, or having an element or plurality of elements having a particular property may contain additional such elements not having that property. The terms including and wherein are used as plain language equivalents of the corresponding terms containing and wherein. Moreover, the terms first, second, third, etc. are used simply as adjuster positions and are not intended to impose numerical requirements or a specific positional order on their objects. The control methods and procedures disclosed herein may be stored as executable instructions in nonvolatile memory and may be executed by a control system comprising a controller in conjunction with various sensors, actuators, and other engine hardware. The specific procedures described herein may represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. As such, the various illustrated actions, operations and/or functions may be performed in the illustrated sequence, in parallel, or in some cases not performed. Likewise, the processing order is not necessarily required to achieve the characteristics and advantages of the exemplary embodiments described herein, but is provided for ease of illustration and description. One or more of the illustrated actions, operations and/or functions may be performed repeatedly depending on the specific strategy being used. In addition, the described actions, operations and/or functions may graphically represent code to be programmed into a non-volatile memory of a computer readable storage medium in the engine control system, where the described actions are performed by executing instructions in the system, including various engine hardware components in combination with electronic controller. This specification provides examples of the invention, including best practices, and to enable one of ordinary skill in the art to practice the invention, including making and using any devices or systems and performing any inherent methods. The patentable scope of an invention is defined by the claims and may include other examples that come to mind to those of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with non-material differences from the literal language of the claims. CLAIM 1. A method of controlling emissions in an engine, comprising adjusting the timing of fuel injection of fuel injectors of an internal combustion engine relative to top dead center (TDC) in response to the consumed effective engine power, proportional to the position of the engine governor, and, as the absorbed effective engine power increases, the amount of timing advance The fuel injection rate is decreased in a first range of engine governor positions and then increased in a second range of engine governor positions comprising larger engine governor positions than the first range. 2. The method according to claim 1, in which additionally: adjusting an upper limit for increasing the amount of fuel injection timing advance of the fuel injectors relative to TDC in response to the consumed effective power of the engine, and when the input effective power of the engine increases, the upper limit for increasing the amount of advancing the fuel injection timing of the fuel injectors relative to TDC is decreased; and adjusting a lower limit for reducing the amount of fuel injection timing advance of the fuel injectors relative to TDC in response to the engine effective power input, wherein, when the engine effective power input increases, the lower limit for decreasing the amount of fuel injection timing advance of the fuel injectors relative to TDC is increased. 3. The method of claim 1, further comprising adjusting the engine's revolutions per minute (RPM) in response to the engine's effective power input, wherein when the engine's effective engine power input increases, the engine speed is increased and the engine burns diesel fuel. 4. The method according to claim 1, wherein the main pressure in the common fuel injection system of the internal combustion engine is further adjusted in response to the consumed effective power of the engine, and when the consumed effective power of the engine -