INCREASING ENGINE EFFICIENCY

FIELD

[0001] The present disclosure relates generally to engine control and particularly to using artificial aspiration systems to increase engine efficiency.

BACKGROUND

[0002] Presently, the power-to-weight ratio of internal combustion engines can be improved using artificial aspiration to supplement the engine air intake manifold pressure. Traditional artificial aspiration methods include driving components directly from the engine or from exhaust pressure. When the engine is operating at low speeds or the exhaust temperature is not at design temperature, there may be insufficient artificial aspiration to operate the engine efficiently. Accordingly, there is a need and desire for improved artificial aspiration methods and systems.

SUMMARY

[0003] In various example embodiments, the present disclosure provides artificial aspiration methods and systems for maximizing engine efficiency. The method includes determining the engine operating status and determining an artificial aspiration goal value based on the engine operating status. The method also includes determining an artificial aspiration system configuration based on the artificial aspiration goal value and the engine operating status and configuring the artificial aspiration system to obtain the determined artificial aspiration system configuration.

[0004] One such embodiment comprises determining the engine status by evaluation of one or more of: an air intake temperature, an engine rotation speed, an exhaust pressure, an exhaust temperature, an engine torque, an atmospheric pressure, and an atmospheric humidity. Furthermore, the engine status may be determined by an engine or sensor signal flag supplied by another engine control or status system. [0005] In one aspect of the method, the artificial aspiration system configuration is determined based on the artificial aspiration goal value and the engine status such that engine fuel usage is minimized and or power is maximized depending on implementation preference. The method may further comprise determining a system configuration comprising a supercharger. The supercharger may be an electrical- mechanical hybrid supercharger. Generally, the hybrid supercharger may comprise a clutch such that the supercharger fan may operate on both electrical and mechanical inputs. In another embodiment, the determined system configuration will have independent values for the mechanical and electrical inputs to the supercharger fan. The method may further include determining a system configuration comprising a turbo booster. The turbo booster may have a turbo brake and a turbo bypass. In another example, the method comprises determining a system configuration comprising at least one aspiration source control valve configured to allow balancing or isolation of the artificial aspiration sources.

[0006] In one such embodiment, configuring the artificial aspiration system to obtain the artificial aspiration system configuration comprises controlling one or more of: a supercharger clutch, a supercharger electric motor, a turbo brake, a turbo bypass, and an aspiration source control valve.

[0007] Disclosed herein is an artificial aspiration efficiency system. The efficiency system includes an artificial aspiration system comprising a plurality of sensors for sensing characteristics of an operating engine and an artificial aspiration control unit comprising a processor connected to receive the sensed characteristics of the engine.

[0008] In one example the processor is configured to determine the engine operating status, determine an artificial aspiration goal value based on the engine operating status, determine an artificial aspiration system configuration based on the artificial aspiration goal value and the engine operating status, and configure the artificial aspiration system to obtain the determined artificial aspiration system configuration. The engine status may be determined by evaluating one or more of: an air intake temperature, an engine rotation speed, an exhaust pressure, an exhaust temperature, an engine torque, an atmospheric pressure, an atmospheric humidity, and engine status signal flags.

[0009] In another example the processor may be further configured such that the artificial aspiration system configuration is determined such that engine fuel usage is minimized and or power is maximized depending on implementation preference.

[0010] The artificial aspiration system may comprise a supercharger. In one embodiment, the supercharger may be an electrical-mechanical hybrid supercharger. Generally, the hybrid supercharger may comprise a clutch such that the supercharger fan may operate on mechanical input. In another example, the artificial aspiration system comprises a turbo booster that may have a turbo brake and a turbo bypass. The artificial aspiration system may further comprise at least one aspiration source control valve configured to allow balancing or isolation of the artificial aspiration sources.

[0011] In another embodiment the artificial aspiration system is configured by controlling one or more of: a supercharger clutch, a supercharger electric motor, a turbo brake, a turbo bypass, and an aspiration source control valve.

[0012] Further areas of applicability of the present disclosure will become apparent from the detailed description, drawings and claims provided hereinafter. It should be understood that the detailed description, including disclosed embodiments and drawings, are merely exemplary in nature intended for purposes of illustration only and are not intended to limit the scope of the invention, its application or use. Thus, variation that do not depart from the gist of the invention are intended to be within the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a schematic of an artificial aspiration efficiency system in accordance with the present disclosure; and

[0014] FIG. 2 is a flow diagram of a method of increasing efficiency in an engine according to the principles of the present disclosure.

DETAILED DESCRIPTION

[0015] In one form, the present disclosure provides a method of increasing the efficiency and or power of an engine using an artificial aspiration system. Artificial aspiration of an engine is desired because it provides for a higher power-to-weight ratio thereby, reducing the size of an engine necessary to output the same amount of power. However, creating the artificial aspiration pressure places additional load on the engine that may not be efficiently handled based on the status of the engine speed, temperature, or other operating or environmental factors.

[0016] Thus, as described below in more detail and in accordance with the disclosed principles, an engine operating status is evaluated to determine an artificial aspiration goal value based on the current operating characteristics of the engine. After the system determines the artificial aspiration goal value, the various artificial aspiration system configurations may then be evaluated to determine which configuration would be most efficient based on the current environmental conditions and operating characteristics of the engine. The artificial aspiration system is then controlled and placed into the efficient configuration and the steps may be repeated, as desired.

[0017] Figure 1 illustrates an example artificial aspiration efficiency system 100 that comprises an engine 101 and a plurality of sensors 160. A single system sensor 160 block is shown, but it should be understood that sensor information may come from multiple independent sensors throughout the system including additional sensors or signals not shown. The sensors 160 may include at least an air intake temperature sensor 161 , an engine rotation speed sensor 162, an exhaust pressure sensor 163, and an exhaust temperature sensor 164. Sensors 161 , 162, 163, and 164 are shown to illustrate where individual sensors may be located within artificial aspiration efficiency system 100 and are together represented as sensors 160. The sensors 160 may also include at least an engine torque sensor, an atmospheric pressure sensor, and an atmospheric humidity sensor. The sensors may be connected to an engine control unit 170 that may collect information from the sensors 160 and generate signal flags based on inputs from the sensors 160 and engine 101.

[0018] The artificial aspiration efficiency system 100 may further comprise a supercharger 1 10, a turbo booster 120, aspiration source control valves 130, and an artificial aspiration control unit 150. The artificial aspiration control unit 150 comprises a processor (P) 151 connected to a memory (M) 152, but it should be understood that artificial aspiration control unit 150 may comprise any programmable controller configured as described herein. Multiple aspiration source control valves 130 are shown, but it should be understood that a single valve capable of blending or isolating multiple aspiration sources may also be used. As an example, the aspiration source control valves 130 could be capable of reacting to reconfiguration either by reacting passively to changes in pressure, such as check valves, or actively by control signals from the artificial aspiration control unit 150, such as solenoid or motor operated valves.

[0019] In one example, the supercharger 1 10 is an electrical-mechanical hybrid supercharger comprising both a mechanical drive source 1 15 and an electric supercharger motor 1 12 drive source to a supercharger fan 1 1 1. Mechanical drive sourcel 15 may be driven by a belt 1 16 or other mechanical linkage (not shown) connected to the engine 101. The supercharger 1 10 may further comprise a clutch 1 13. In one example, clutch 113 is a centripetal clutch configured to transfer the input load of the supercharger fan 1 1 1 from the electric supercharger motor 112 to the mechanical drive source 1 15 as the rotational speed of the mechanical drive source 1 15 increases. In another example, the clutch 1 13 is a computer controlled clutch configured to allow independent contribution of the mechanical drive source 1 15 and the electric supercharger motor 1 12 to the driving power of supercharger fan 11 1. In another example, the clutch 113 is configured to allow only electric supercharger motor 1 12 input to the supercharger fan 11 1 , only mechanical drive source 115 input to the supercharger fan 1 1 1 , or any combination of electric supercharger motor 1 12 and mechanical drive source 1 15 inputs to the supercharger fan 1 1 1 .

[0020] The turbo booster 120 may comprise a turbo brake 122 and a turbo bypass 121 . The turbo bypass 121 may be separate exhaust piping that bypasses the turbo booster or it may be a vane bypass system within the turbo booster 120. The turbo bypass 121 may be configured to reduce exhaust back pressure when the turbo booster 120 is not in use.

[0021] In one example, the artificial aspiration control unit 150 includes connections from the sensors 160. In another example, the artificial aspiration control unit 150 includes connections from the engine control unit 170 or other vehicle status systems (not shown). The artificial aspiration control unit 150 is further connected to and configured to control at least one of: the electric supercharger motor 1 12, supercharger clutch 1 13, turbo bypass 121 , turbo brake 122, and/or aspiration source control valves 130.

[0022] Figure 2 shows a flowchart of a method 200 performed by the artificial aspiration control unit 150 for increasing efficiency in the engine 101 . At step 210, the engine 101 operating status is determined by collecting information from sensors 160 and/or engine control unit 170. The engine operating status may include operational information such as engine rotation speed, engine torque, and exhaust pressure and temperature, or it may include atmospheric information such as atmospheric pressure, atmospheric humidity, and air intake temperature. At step 220, the engine operating status is evaluated and an artificial aspiration goal value is determined based on the engine operating status determined at step 210. In one example, the artificial aspiration goal value is a combination of artificial aspiration pressure and flow rate.

[0023] The method continues at step 230 where an artificial aspiration system configuration is determined based on the artificial aspiration goal value and the engine operating status. In one example, the system configuration will be a combination of electric supercharger motor 1 12 current and voltage, supercharger clutch 1 13 position, turbo bypass 121 position, turbo brake 122 force, and the position of aspiration source control valves 130 such that engine efficiency is maximized. It should be understood, however, that not all system components are required to realize a gain in efficiency. In one example, engine efficiency is maximized by selecting the system configuration that obtains the artificial aspiration goal value with the least energy input thereby requiring the least amount of fuel for the desired power output. At step 240, the artificial aspiration system is configured into the configuration determined at step 230.

[0024] As can be seen, by determining an artificial aspiration system configuration based on engine operating characteristics, the engine will always be operating efficiently by using an artificial aspiration system configuration that places the least additional load on the engine given the target artificial aspiration goal value.