Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2425—Particular ways of programming the data
  • F02D41/2429—Methods of calibrating or learning
  • F02D41/2432—Methods of calibration
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D33/00—Controlling delivery of fuel or combustion-air, not otherwise provided for
  • F02D33/003—Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus ; Failure or leakage prevention; Diagnosis or detection of failure; Arrangement of sensors in the fuel system; Electric wiring; Electrostatic discharge
  • F02D33/006—Controlling the feeding of liquid fuel from storage containers to carburettors or fuel-injection apparatus ; Failure or leakage prevention; Diagnosis or detection of failure; Arrangement of sensors in the fuel system; Electric wiring; Electrostatic discharge depending on engine operating conditions, e.g. start, stop or ambient conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/22—Safety or indicating devices for abnormal conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2425—Particular ways of programming the data
  • F02D41/2429—Methods of calibrating or learning
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2425—Particular ways of programming the data
  • F02D41/2429—Methods of calibrating or learning
  • F02D41/2441—Methods of calibrating or learning characterised by the learning conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2425—Particular ways of programming the data
  • F02D41/2429—Methods of calibrating or learning
  • F02D41/2451—Methods of calibrating or learning characterised by what is learned or calibrated
  • F02D41/2464—Characteristics of actuators
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2425—Particular ways of programming the data
  • F02D41/2429—Methods of calibrating or learning
  • F02D41/2477—Methods of calibrating or learning characterised by the method used for learning
  • F02D41/248—Methods of calibrating or learning characterised by the method used for learning using a plurality of learned values
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/30—Controlling fuel injection
  • F02D41/38—Controlling fuel injection of the high pressure type
  • F02D41/3809—Common rail control systems
  • F02D41/3836—Controlling the fuel pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/0011—Constructional details; Manufacturing or assembly of elements of fuel systems; Materials therefor
  • F02M37/0023—Valves in the fuel supply and return system
  • F02M37/0029—Pressure regulator in the low pressure fuel system
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/04—Feeding by means of driven pumps
  • F02M37/08—Feeding by means of driven pumps electrically driven
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
  • F04D15/0066—Control, e.g. regulation, of pumps, pumping installations or systems by changing the speed, e.g. of the driving engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
  • F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
  • F04D15/0088—Testing machines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/22—Safety or indicating devices for abnormal conditions
  • F02D2041/224—Diagnosis of the fuel system
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/06—Fuel or fuel supply system parameters
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/06—Fuel or fuel supply system parameters
  • F02D2200/0602—Fuel pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
  • F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
  • F02D41/2425—Particular ways of programming the data
  • F02D41/2429—Methods of calibrating or learning
  • F02D41/2438—Active learning methods
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/30—Controlling fuel injection
  • F02D41/3082—Control of electrical fuel pumps
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/04—Feeding by means of driven pumps
  • F02M37/08—Feeding by means of driven pumps electrically driven
  • F02M37/10—Feeding by means of driven pumps electrically driven submerged in fuel, e.g. in reservoir
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M37/00—Apparatus or systems for feeding liquid fuel from storage containers to carburettors or fuel-injection apparatus; Arrangements for purifying liquid fuel specially adapted for, or arranged on, internal-combustion engines
  • F02M37/04—Feeding by means of driven pumps
  • F02M37/18—Feeding by means of driven pumps characterised by provision of main and auxiliary pumps

Definitions

• the invention relates to a first method for determining a representative for a component tolerance and a state of wear of a fuel pump inflection point of a parameter course, wherein the fuel pump is provided for a fuel supply system for use in a device which is equipped with an internal combustion engine.
• the invention further relates to a second method for calibrating such a fuel pump using the first method.
• the invention further relates to a computer program and a computer program product for carrying out these two methods, a fuel supply system for use in a device equipped with an internal combustion engine, and a device equipped with an internal combustion engine and such a fuel supply system.
• a device or system Under a device or system is any type of device or system to understand, which is equipped with a United combustion engine and which must be supplied for operation with a liquid fuel, in particular by passenger cars and / or commercial vehicles, but also stationary or mobile power generator. Under a liquid fuel is in particular a gasoline or diesel fuel or an alternative, liquid, combustible fuel to understand.
• An internal combustion engine is supplied depending on the operating point in accordance with its fuel demand by a fuel pump arranged for example in a fuel tank with a force.
• the fuel delivery through the fuel pump is done purely for cost reasons purely controlled ("open loop") and is therefore subject to no target-actual comparison, which is as such for a control (“closed loop”) characterizing. Therefore, this controlled fuel delivery is subject to a certain inaccuracy, on the one hand, a production-related component tolerance of the fuel pump and on the other hand wear of the fuel pump are the cause.
• Such a natural wear arises in particular in a so-called positive displacement - ie a pump that works on the so-called displacement principle - over their lifetime increasingly, so that there is a deviation between a actually representing flow and a set flow rate of the fuel pump over its lifetime increasingly apparent.
• the component tolerance of the fuel pump in turn is wear-dependent, so that it changes over the lifetime of the fuel pump. This is also referred to as a lifetime of the fuel pump ver wear-dependent changing tolerance position of the fuel pump.
• Fuel pump at the end of their lifetime meets the requirements placed on them. However, this requires an increased energy consumption of the fuel pump.
• An object of the invention is therefore to provide a more accurate fuel delivery.
• a further object of the invention is to reduce the energy consumption of such a fuel pump and thus to contribute to an improved CCg balance of an engine-operated device.
• the proposed, first method is based on a determination of a component tolerance and wear state of a fuel pump representative kink point of a parameter curve.
• the method comprises the following steps:
• Stepwise increasing a speed n of a fuel pump motor to increase the pressure upstream of the locked position while determining a set in the fuel pump motor phase current i, wherein the speed is increased until a valve of the fuel supply system for pressure reduction opens (OP opening point), wherein the individual speed levels, a determined value for the phase current i is assigned, and
• phase current i - this may be a direct current or a Wech selstrom - is proportional to the pressure generated in the fuel pump p and to a first approximation proportional to the pressure p upstream of the locked point. This proportionality represents an identifiable system property.
• a partial or complete blockage of the fuel-carrying body is to be understood as meaning a partial constriction or a complete blockage of the fuel-carrying body by means of a shut-off device.
• the shut-off device may be, for example, a separate, actively controllable valve or a high-pressure pump, which as such has a low-pressure inlet and a high-pressure outlet, which each act in the sense of such a valve.
• the proposed first method provides a cost-effective and effective solution for determining a component tolerance and a state of wear of a fuel pump representative kink point of a parameter curve.
• the first method contributes to compensate for the initially mentioned inaccuracy of purely controlled th fuel delivery. This in turn contributes to an energy saving in connection with the control of the fuel pump motor and thus also to an improved CO 2 balance of a device which is equipped with an internal combustion engine.
• the proposed second method is based on a calibration of a fuel pump using the first method described above.
• the second method comprises the following steps:
• a first set of value pairs of one respective phase current i and an associated rotational speed n below the break point (OP) is approximated by means of a first straight line
• a second set of pairs of values each of a phase current i and an associated rotational speed n above the break point ( OP) is approximated by means of a second straight line and an intersection point between the two lines is determined
• the intersection of the break point (OP) ent speaks, which corresponds to the opening time (OP) of the valve korres, wherein the intersection of a speed n 0p is assigned ,
• a first break point (OP n ) as a reference point or initial point for an unspun fuel pump and at a second, later time (t 2 ) a second
• Break point (OP v ) to determine the current state of wear of the fuel pump corresponding.
• a speed difference Dh between the first break point (OP n ) and the second break point (OP v ) is determined, the speed difference Dh for energy consumption optimized control of the fuel pump until the next souzuprint generating calibration process in the sense of a fixed value to a Depending on the engine requirement, the determined speed of the fuel pump is added up.
• the proposed second method or Kalibrie rungs vide the initially mentioned inaccuracy of the controlled fuel delivery is compensated, without having to resort to a control ("closed loop") with a sensor-based actual value acquisition.
• this calibration process also represents a cost-effective solution, in particular in connection with a pressure-sensorless concept.
• a pressure sensorless concept is understood to mean a fuel supply system whose low-pressure part has no pressure sensor built into the hardware.
• the said compensation of the inaccuracy in turn contributes to an energy saving in connection with the control of the fuel pump motor and thus also to an improved CO 2 balance of a device which is equipped with an internal combustion engine.
• the speed difference is only used from a determinable defined minimum value for calibrating the fuel pump.
• speed differences below this minimum value can be disregarded.
• the first and the second method during a coasting operation of the internal combustion engine or during an operating phase of the combustion tion motor performed at least approximately constant conditions condi- tions.
• An operating phase of the internal combustion engine under at least approximately constant conditions would e.g. an idling phase in which the internal combustion engine does not emit significant torque via the crankshaft.
• an operating phase is equally conceivable under at least approximately constant load conditions under which the internal combustion engine delivers a corresponding torque via the crankshaft.
• the first and the second method are carried out at regular intervals to determine the representative of the component tolerance and the United schleibschreib the fuel pump break point of the parameter curve (i, n) on the one hand and the calibration of the fuel pump on the other hand over its lifetime to update .
• the first method for determining the reference point or initial point can be carried out for the first time after a first operating time of eg 1 to 3 hours (h) or a mileage of eg 20 to 100 km, after which the fuel pump is still unworn.
• the first and second procedures were scheduled at intervals each corresponding to a multiple of the first operating time or the first mileage, for example every 10 to 100 hours (h) or every 500 to 1000 km.
• the intervals following the first number of operating hours or mileage do not have to be constant. For example, these intervals could be reduced and / or increased over the lifetime of the fuel pump.
• the two methods could also be carried out, for example, after a definable number of driving cycles of the vehicle, for which corresponding intervals can be defined in an analogous manner.
• a drive cycle is to be understood as a cycle which is defined by the process of switching on, followed by the operation of switching off an ignition.
• the two methods could also be carried out after each filling process of a fuel tank. This would compensate for the influence of a meanwhile changing fuel quality on the two methods.
• stepwise He increase the speed n of the fuel pump motor is proposed to increase the speed n at least substantially in the form of a speed ramp.
• a progressive or degressive drive course is also suitable for the stepwise increase of the rotational speed n.
• the speed n associated with the respective break point is stored non-volatilely in a memory of a control unit for sys-side utilization. Similarly, the determined speed difference non-volatile stored in the memory of the control unit for system utilization.
• the computer program and the computer program product can each be understood in terms of a functional module architecture, such a functional module architecture having at least one function block, so that the computer program and the computer program product each equate to a device having at least one means for
• the at least one means of the device corresponds to said at least one functional block.
• the fuel supply system includes a low pressure part with an electric motor driven fuel pump to promote fuel from a fuel tank, a shut-off for at least partial or complete, active obstruction of a fuel-carrying point in a flow line of the fuel supply system downstream of the fuel pump to conditions under a defined loading a Fuel flow to an internal combustion engine at least to reduce or even completely prevent, as well as at least one control unit in which the first and second methods are imaged software or implemen ted benefits.
• the low pressure part includes a valve for pressure reduction in the overpressure case.
• the Kraftstoffversor supply system in addition to the low-pressure part also have a high-pressure part, which is in communication with the low-pressure part in fluid communication.
• the fuel supply system may include a high-pressure pump, which connects the low-pressure part with the high-pressure part and forms the shut-off unit.
• the fuel supply system can have, in addition to a motor control unit, a pump control unit which is in communication communication with the engine control unit and in which the first and second methods are imaged or implemented by software.
• the low-pressure part can be designed so that in the unlocked state of the fuel-carrying body by means of the fuel pump, a fuel pressure of up to about 3.5 bar in the low-pressure part is reached, whereas in at least partially or completely blocked state of the fuel leading point by means of the fuel pump Fuel pressure of up to about 3, 9bar can be reached at which a valve opens to reduce pressure.
• the valve may be, for example, a valve of a fuel-carrying return line of the fuel supply system. Basically, this pressure reduction does not necessarily require such a return line. Also, for this pressure reduction would be e.g. only one valve is conceivable, which is arranged within a fuel tank and via which a fuel is returned to the fuel tank by opening the valve.
• a use of a fuel supply system of the type described above is proposed in a device or system operated in particular with gasoline or diesel fuel, which is equipped with an internal combustion engine.
• a device or plant which is equipped with an internal combustion engine, wherein the device or plant comprises a fuel supply system of the type described above be.
• Fig.l is a schematic representation of a controlled
• FIG. 3 shows a schematic, second illustration of a pre
• FIG. 1 illustrates a purely controlled fuel supply system 2 according to the prior art.
• a motor control unit 4 outputs depending on an operating point of a United combustion engine, a speed request to a Pumpensteu eratti 8, which is in communication with the engine control unit 4 in Medu.
• the pump control unit 8 controls in turn an electric motor operated fuel pump 12 - also called prefeed pump - on, which is as such part of a so-called fuel delivery unit 10.
• the rotational speed requirement n A results, for example, from a transmission characteristic curve in the form of a three-dimensional characteristic diagram 6, which can be spanned, for example, via a rotational speed n VM and a load rl of the internal combustion engine.
• the transfer characteristic could just as well represent a complex multidimensional transfer characteristic. In both cases, the transfer characteristic is pumped out by means of an unworn fuel pump 12 and then applied for a series application.
• Fuel filter 15 is promoted, from which a return line 16 for excess fuel leads back into the surge chamber. From the fuel filter 15, the fuel is then conveyed via a further supply line 18 to a high pressure pump 20 for further compression, which in this example generates a high pressure for a so-called common rail system ("common rail” means as much as “common line” ).
• FIG. 2 illustrates a greatly simplified fuel supply system 2, in which in a Pumpensteu eratti 8, the previously described, proposed first and second method implemented by software or mapped.
• the pump control unit 8 is communicating onsimpl with the electric motor operated fuel pump fuel 12, which promotes a fuel from a swirl pot within a fuel tank 9 to a high pressure pump, to which only the low pressure side inlet and variable, high pressure side outlet 26 are shown for simplicity , Further, a pressure relief valve 24 is shown as part of a return line through which excess fuel flows back into the fuel tank 9.
• the fuel supply system 2 for supplying a combustion engine 28, for example in the form of a diesel engine.
• the fuel supply system 2 comprises, in addition to a derdruckteil 30 and a high-pressure part 32, which communicates with the low-pressure part 30 via a high-pressure pump 20 in fluid communication connection.
• the high-pressure pump 20 is thus both part of the low-pressure part 30 and part of the high-pressure part 32.
• the fuel supply system 2 further comprises in addition to a motor control unit 4 and a pump control unit 8, which communicates with the engine control unit 4 in Karlunikationsver bond and in which the two methods described above software implemented or mapped. Alternatively, the two methods described above could also be represented in software in the engine control unit 4.
• the engine control unit 4 detects an operating point-dependent fuel demand of the internal combustion engine 28 and derives therefrom a speed request to the pump control unit 8, which in turn then an electric motor operated
• Fuel pump 12 controls a fuel delivery unit 10 for a position of a corresponding fuel delivery volume.
• the fuel pump 12 promotes, for example, a diesel fuel from a arranged within a fuel tank 9 swirl pot 10 via a flow line 18 to the high-pressure pump 20.
• the fuel arrives at the pressure pump 20 at a pressure of about 3 to 6bar.
• a example of the high pressure pump 20 belonging valve eg in the form of a spring-loaded ball valve 36 limits the form in the low pressure part 30 depending on the version to about 3 to 6 bar (p max ) ⁇ Excess fuel passes through a return line 34 back into the fuel tank.
• the high pressure pump 20 which may be formed in the form of a so-called radial piston pump, further compresses the fuel depending on the application to a pressure of up to 2500 bar. If the pressure in the pump chamber exceeds a rail pressure, a motor-side outlet valve 20b, 26 (FIG. 2) opens and the fuel flows through a high-pressure line of the high-pressure part 32 to a common rail ("common line").
• Fig. 4 illustrates a representative correlation between a rotational speed n of the fuel pump 12 and the pressure p generated in the fuel pump 12 due to a stepwise increase of the rotational speed of the fuel pump motor.
• a speed control of the fuel pump motor both as a mechanically commutated DC motor or electronically commutated alternating current motor, can be performed in the form of a permanently excited Syn chronher machine.
• a phase current i of the fuel pump motor can also be plotted, because the phase current i which is load-dependent in the fuel pump motor is proportional to the pressure p in the fuel pump.
• the phase current i can be a direct current or an alternating current.
• the pressure p in the fuel pump is in first approximation proportional to the pressure p upstream of the blocked point.
• FIG. 5 illustrates a speed increase in thousands of stages (1000, 2000, 3000,... RPM), with the individual speed stages being held for approximately 2 s.
• the hold time of approx. 2s is only an example. Basically, this holding time may vary depending on the configuration of the pump control unit 8, i. the fuel pump electronics, also take significantly lower values, e.g. 50 to 200ms.
• a phase current i which sets in the fuel pump motor is then determined. This results in a value pair of a speed n and an associated phase current i for each individual speed step.
• a first set of pairs of values of i and n is below one of the break points OP n , OP v illustrated in each case, and a second set of pairs of values of i and n above the respective break point OP n , OP v shown .
• a first straight line is then laid through the first set of value pairs of i and n, whereas a second straight line is laid by the second set of value pairs of i and n.
• the two straight lines intersect at a point or point of intersection, which corresponds to the respective, approximated kink point OP n , OP v .
• the respective break point OP n , OP v is a speed n n , n v uniquely assignable.
• the first steeper parameter curve illustrates an unsoldered or new fuel pump
• the second flatter parameter curve illustrates an already partially worn fuel pump.
• the two parameter curves each have a break point OP n , OP v , in which the respective straight line sections meet.
• the two break points OP n , OP v correspond to an opening time of the valve 24 ( Figure 2), 36 an associated fuel-carrying return line of the low pressure part 30.
• the second method further comprises the steps:
• the proposed calibration is a calibration performed at regular intervals over a lifetime of the fuel pump 12 of a device such as a vehicle. So you can too speak of an "online calibration". It is beaten before, the calibration about after a definable duration of the fuel pump - for example, measured in hours of operation (h) - to perform regularly or after a definable mileage of the vehicle.
• the first and second methods may be repeated at regular intervals for determining a representative state of wear, wherein the intervals following the first interval correspond to a multiple of the first operating time or number of kilometers respectively.
• the second and each additional mileage of the vehicle could be 500 km or the second and each additional operating hours of 10 hours.
• the second method can then be carried out for the first time, which in addition to the
• Steps of the first method has the determination of said speed difference Dh for the purpose of calibration to the object.
• the determination of the second break point OP v and the calibration itself are therefore subject to a regular repetition in order to update the determination of the state of wear of the fuel pump over its entire lifetime.
• the fact that only calibrated discontinuously, the computational cost of the pump control unit 8 is kept minimal.
• control unit in which the two methods are implemented by software, on the one hand the determination of a need and on the other hand, the determination of readiness to carry out the two methods.
• Both the reference point or "initial point” and the following values of the second inflection point OP v to be updated are stored non-volatile in a memory of the pump control unit 8.
• the proposed second method or calibration method the initially mentioned inaccuracy of the control th fuel delivery is compensated, without having to resort to a Re ("closed loop"). This in turn contributes to an energy saving in connection with the control of the fuel pump motor and thus also to an improved CO2 balance of the vehicle.
• the vehicle instead of the vehicle, it may be a device or installation in the form of a stationary or mobile power generator.
• the pump control unit 8 comprises analogous to the motor control unit 4 a data-connected to a memory system and a bus system digital microprocessor unit (CPU), a random access memory (RAM) and a memory means.
• the CPU is adapted to execute instructions executed as a program stored in a memory system, to detect input signals from the data bus, and to output signals to the data bus.
• the storage system may have at least one storage medium in the form of a magnetic solid and / or other non-volatile medium on which a corresponding computer program for carrying out the method is stored.
• the program may be such that it is capable of embodying the methods described herein so that the CPU may perform the steps of such methods and thereby control the fuel pump.
• Suitable for performing the two methods described above is a computer program having program code means for performing all steps of any one of the method claims when executing the program in the CPU.
• the computer program can be integrated with simple means in an existing control electronics and used to control the fuel pump and its electric motor.
• a computer program product with program code means which are stored on a computer-readable data carrier ge to perform the method according to any of the method claims, when the computer program product is executed in the CPU.
• the computer program product can also be integrated into the pump control unit 8 as a retrofit option.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)

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• 2017
  • 2017-11-28 DE DE102017221333.7A patent/DE102017221333B4/de active Active
• 2018
  • 2018-11-01 EP EP18796637.9A patent/EP3717764A1/de not_active Withdrawn
  • 2018-11-01 CN CN201880065133.3A patent/CN111542690A/zh active Pending
  • 2018-11-01 US US16/767,564 patent/US11261817B2/en active Active
  • 2018-11-01 WO PCT/EP2018/079924 patent/WO2019105676A1/de unknown

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