Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D23/00—Controlling engines characterised by their being supercharged
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
  • F02B37/12—Control of the pumps
  • F02B37/18—Control of the pumps by bypassing exhaust from the inlet to the outlet of turbine or to the atmosphere
• • 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
  • F02D41/0002—Controlling intake air
  • F02D41/0007—Controlling intake air for control of turbo-charged or super-charged engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
  • F02B37/004—Engines characterised by provision of pumps driven at least for part of the time by exhaust with exhaust drives arranged in series
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
  • F02B37/013—Engines characterised by provision of pumps driven at least for part of the time by exhaust with exhaust-driven pumps arranged in series
• • 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
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/14—Introducing closed-loop corrections
  • F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
  • F02D2041/1433—Introducing closed-loop corrections characterised by the control or regulation method using a model or simulation of the system
  • F02D2041/1434—Inverse model
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/12—Improving ICE efficiencies

Definitions

• the present invention relates to the motor control and more particularly to the control of a turbocharger supercharging device by a method of determining a position setpoint of a turbine bypass actuator as a function of a compression ratio setpoint. .
• the invention applies to a supercharging device comprising a turbocharger with fixed geometry, or two such turbochargers connected in series.
• turbochargers With the increased performance of supercharged engines, boost pressure levels are increasing and turbochargers are increasingly in demand. It is important to control these turbochargers as finely as possible to avoid deterioration of the turbocharger while improving the brio of the vehicle during acceleration.
• the particulate filter is a solution that reduces the amount of particles released into the environment. It is composed of a set of micro channels in which a large part of the particles are trapped. Once the filter is full, empty the filter by burning the particles, this phase is called "regeneration". The regeneration can be obtained either by a heating device or by specific engine settings.
• the particulate filter is placed in the exhaust line downstream of the low pressure turbine.
• control method advantageously uses a compression ratio variable compressor to drive a turbocharger in the case where it is unique.
• the method replaces a dual-loop control by a control at a given moment of one or other of the turbochargers, combined with a manager that selects the turbocharger piloted.
• the invention relates to a method for a supercharger turbocharger of a heat engine comprising a turbine driven by the exhaust gas, a compressor driven in rotation by the turbine to compress the intake air, and a turbine bypass actuator for controlling a flow rate of air not passing through the turbine, said method determining a position value of the bypass actuator as a function of a compression ratio setpoint, a compression ratio measurement, a flow measurement through the compressor, a pressure measurement downstream of the turbine, a pressure measurement downstream of the compressor, a temperature measurement upstream of the compressor; the turbine, and a measure of temperature upstream of the compressor.
• the determination of a position setpoint of the bypass actuator comprises: - determination of an expansion ratio setpoint as a function of the compression ratio setpoint and the measurement compression ratio,
• the determination of the position setpoint of the bypass actuator, as a function of the relaxation rate setpoint uses an inverse actuator model.
• the flash rate reference is, prior to the use of the inverse actuator model, saturated as a function of a maximum permissible pressure downstream of the turbine, according to the formula:
• PRt, s P , sat is the set point of relaxation after saturation
• PR t , s p is the set point of expansion before saturation
• P dt is the pressure downstream of the turbine
• Pdt, ma ⁇ is the maximum acceptable pressure downstream of the turbine
• the expansion ratio setpoint is equal to the sum of an open loop expansion ratio setpoint calculated as a function of the compression ratio setpoint by a prepositioning module, and a closed loop expansion rate setpoint calculated as a function of an error between the compression ratio setpoint and the compression ratio measurement by a first controller module.
• the position setpoint of one bypass actuator is equal to the sum of an open loop position setpoint calculated as a function of the compression ratio setpoint, and a closed loop position setpoint calculated as a function of an error between the compression ratio setpoint and the compression ratio measurement by a second controller module.
• the determination of the open-loop position instruction comprises the steps of:
• the maximum position setpoint is determined as a function of the open-loop expansion ratio using an inverse actuator model.
• PRt, s P , sat is the set point of relaxation after saturation
• PR t , s p is the set point of expansion before saturation
• P dt is the pressure downstream of the turbine
• Pdt, ma ⁇ is the maximum acceptable pressure downstream of the turbine, the set value of the saturated expansion ratio subsequently replacing the initial value of the open loop expansion ratio.
• the prepositioning module comprises the following steps: determination of a corrected flow rate measurement of intake air through the compressor as a function of an air flow measurement of admission through the compressor, according to the formula: W cmcor
• W c , m, co r is the corrected intake air flow measurement through the compressor
• W c , m is the intake air flow measurement through the compressor
• T uc is a temperature upstream of the compressor
• P uc is a pressure upstream of the compressor
• T c , ref is a reference temperature of the compressor
• P c , r e f is a reference pressure of the compressor
• N sp is the speed setpoint of the turbocharger
• corc is the corrected speed setpoint relative to the turbocharger compressor
• T uc is the temperature upstream of the compressor
• T c ref is the reference temperature of the compressor, - calculation of a compressor efficiency according to the corrected speed reference relative to the turbocharger compressor and the corrected intake air flow rate setpoint through the compressor, by means of a function of the corrected speed setpoint relative to the turbocharger compressor and the flow setpoint corrected intake air through the compressor, said function being defined by two-dimensional mapping,
• W c , m is the intake air flow measurement through the compressor
• ⁇ c is the efficiency of the compressor
• T uc is the temperature upstream of the compressor
• PR c , sp is the compression ratio setpoint of the compressor
• Cp c is a first thermodynamic constant of the intake air
• ⁇ c is a second thermodynamic constant of the intake air
• N sp is the turbocharger speed setpoint
• N sp cort is the corrected speed setpoint relative to the turbine of the turbocharger
• T ut is a temperature upstream of the turbine
• T t ref is a reference temperature of the turbine
• PRt, sp, oi is the open loop expansion ratio of the turbine
• Ht, sp is the power setpoint of the turbine
• cort is the corrected speed setpoint relative to the turbine of the turbocharger
• Ht, sp is the power setpoint of the turbine
• PRt, s P where is the open-loop expansion ratio of the turbine, Cp t is a first thermodynamic constant of the exhaust gas,
• Y t is a second thermodynamic constant of the exhaust gas
• ⁇ t is a turbine efficiency that can be expressed by means of a function of the corrected speed reference relative to the turbine of the turbocompressor and the reference rate of expansion in an open loop, said function being defined by a two-dimensional map, W t , S p is an exhaust gas flow setpoint through the turbine determined by the formula:
• W t , S p is an exhaust gas flow setpoint through the turbine
• W t , sp , cor is a corrected flow rate setpoint of the exhaust gas through the turbine that can be expressed by means of a function of the corrected speed setpoint relative to the turbocharger turbine and the open-loop expansion ratio setpoint, said function being defined by two-dimensional mapping
• T ut is a temperature upstream of the turbine
• T t ref is a reference temperature of the turbine
• P dt is a pressure downstream of the turbine
• the first controller module is a controller configured to cancel said error.
• the controller uses fuzzy logic rules.
• the regulator comprises a Proportional Integral Derivative module, PID.
• bypass actuator of the turbine is modeled by an equation of Barré Saint Venant, according to the formula:
• PR denotes the input quantity, respectively:
• PR t , S p the relaxation ratio reference, PR t , sp , where the open loop expansion ratio setpoint
• W act is a flow through the actuator
• S act is a section of the actuator
• P dt is a pressure downstream of the turbine
• T dt is a temperature downstream of the turbine, ⁇ a function of the variable X, defined by:
• Y t is a first thermodynamic constant of the exhaust gas, equal to 1.4
• R is the gas constant, equal to 287 J / kg / K.
• the flow rate through the actuator is determined according to the formula: O U U U W c, m is a measure of flow through the compressor, W t, s p is a flow setpoint through the turbine.
• said section of the actuator is mapped as a function of the position setpoint of said actuator and the trigger ratio setpoint.
• the invention also relates to a method, for a dual supercharging device with a fixed geometry of a heat engine, comprising:
• a first high pressure turbocharger comprising a high pressure turbine driven by the exhaust gases from said heat engine, a high pressure compressor rotated by the high pressure turbine in order to compress the intake air injected into the heat engine, and a high pressure bypass actuator of the high pressure turbine for controlling a flow of air not passing through the high pressure turbine,
• a second low pressure turbocharger comprising a low pressure turbine driven by the exhaust gases from said engine via the high pressure turbine or the high pressure bypass actuator, a low pressure compressor driven in rotation by the low pressure turbine to compress the intake air injected into the engine via the high pressure compressor, and a low pressure bypass actuator of the low pressure turbine to control a flow of air not passing through the low pressure turbine, and a bypass valve of the high pressure compressor selectively bypassing the high pressure compressor to directly connect the low pressure compressor to the engine, determining a control setpoint of the high bypass actuator pressure and a command setpoint of the low pressure bypass actuator according to a high pressure pressure ratio set point, low pressure pressure ratio set point, high pressure pressure ratio measurement, low pressure pressure ratio measurement, air flow measurement high pressure and low pressure compressors, pressure measurements downstream respectively of the high pressure turbine and the low pressure turbine, downstream pressure measurements respectively of the high pressure compressor and the low pressure compressor, temperature measurements.
• said method comprising the following steps: - selection by means of a transmission manager a bypass actuator to be controlled from the high pressure bypass actuator and the low pressure bypass actuator,
• the selection step is performed by the manager according to the following rules: the high-pressure bypass actuator is controlled when the engine speed is below a threshold, the valve of bypass of the high pressure compressor being controlled closed and the low pressure bypass actuator being controlled closed,
• the low pressure bypass actuator is controlled when the engine speed is above a threshold, the bypass valve of the high pressure compressor being controlled open and the high pressure bypass actuator being controlled open .
• the threshold engine speed is equal to 2750 rpm.
• FIG. 1 illustrates a heat engine with a turbocharger
• FIG. 2 illustrates a heat engine equipped with a supercharging device comprising two turbochargers
• FIG. 3 shows a block diagram of a "series" embodiment of the method according to the invention
• FIG. 4 shows a block diagram of a "parallel" embodiment of the method according to the invention
• FIG. 5 shows a block diagram integrating two series or parallel modules
• FIGS. 6 and 7 respectively show a map and a table of numerical values defining the function f 1, for the high pressure turbocharger
• FIGS. mapping and a table of numerical values defining the function f1 for the low pressure turbocharger
• Figures 10 and 11 respectively show a map and a table of numerical values defining the function f2, for the high pressure turbocharger
• Figures 12 and 13 present respectively a map and a table of numerical values defining the function f2, for the low-pressure turbocharger
• - Figures 14 and 15 respectively show a map and a table of numerical values defining the function F "1 , for the high-pressure turbocharger
• the Figures 16 and 17 show respectively a mapping and an array of numerical values defining the function F "1 , for the low pressure turbocharger
• FIGS. 18 and 19 illustrate the results obtained respectively with the serial module and with the parallel module.
• N speed or rotational speed (turbocharger)
• PR pressure ratio (compressor compression ratio, turbine expansion ratio)
• thermodynamic constant coefficient equal to Cp / Cv
• J moment of inertia (turbocharger)
• FIG. 1 illustrates the context of the invention in the case of a single turbocharger 1.
• a heat engine 4 typically receives air intake pipes 6 from the air 5.
• the engine 4 produces exhaust gases 7 that escape through exhaust pipes 8.
• a turbocharger 1 for boosting increases the amount of exhaust gas.
• the turbocharger 1 comprises a turbine 2 and a compressor 3.
• the turbine 2 is fluidly connected to the exhaust pipes 8 to be driven by the exhaust gas 7 from the thermal engine 4.
• the turbine 2 is mechanically secured to the compressor 3 which rotates.
• the compressor 3 is fluidly connected to the intake manifolds 6, so that the compressor 3 compresses the intake air 5 before entering the heat engine 4. It is possible to isolate the turbine 2 by means of a By-pass actuator 15. It is possible to isolate the compressor by means of a bypass valve 14.
• the reference 9 is an air flow sensor W c , m intake 5.
• FIG. 2 illustrates the context of the invention in the case of a double turbocharger 1, 11.
• a first high-pressure turbocharger 1 is identical to the turbocharger previously described with a high-pressure turbine 2, a high-pressure compressor 3 and an actuator proportional control of high-pressure bypass 15 makes it possible to regulate a flow rate that does not pass through the high-pressure turbine 2.
• a second low pressure turbocharger 11 is connected in series with the first turbocharger 1.
• the low pressure turbine 12 is driven by the exhaust gas 7 exiting downstream of the high pressure turbine 2, or when it is at least partially controlled open, high pressure bypass actuator. At the outlet of the low-pressure turbine 12, the exhaust gas 7 is directed towards the exhaust.
• the low-pressure turbine 12 is mechanically secured to the low-pressure compressor 13 which it rotates.
• the low pressure compressor 13 receives the air from the air filter compresses it before transmitting it upstream of the high pressure compressor 3. If the on-off bypass valve 14 is open, the low-pressure compressor 13 transmits the air directly to the engine 4 via the intake manif
• the two proportionally controllable high pressure and low pressure bypass actuators 16 are arranged between the upstream and downstream respectively of the high pressure turbine 2 and the low pressure turbine 12.
• the bypass valve 14 compressor controllable in all or nothing is arranged between the upstream and downstream of the compressor 3 high pressure.
• the central module of the method comprises a step of determining a position setpoint ⁇ sp of a bypass actuator 15, 16 as a function of a compression ratio setpoint PR c , sP and d.
• a pressure ratio measurement PR c , m - Two pressure ratios PR can be defined as the ratio of the upstream pressure P 11 to the downstream pressure P d .
• this pressure ratio is called compression ratio PR C and is equal
• relaxation rate PR t is equal to
• the central module accepts as input a compression ratio setpoint PR c , sP from which are determined quantities in open loop. In order to refine the method, closed loop quantities are also determined. For this, the method is looped back to a magnitude indicative of the response of the system 20.
• This central module can be implemented according to several embodiments. Two illustrative embodiments are presented here. These two modes use identical or similar modules organized differently. A first "series" embodiment is illustrated in FIG. 3. A second "parallel" embodiment is illustrated in FIG.
• the determination of a position command ⁇ sp of the bypass actuator 15, 16 can be decomposed into a first determination step, by the blocks 21, 22 , 23, of a relaxation ratio setpoint PR t , sp as a function of the compression ratio setpoint PR c , sP and of the compression ratio measurement PR c , m , or of the distance ⁇ P R C , available as input, followed by a second step of determining a position setpoint ⁇ sp of the bypass actuator 15, 16 as a function of the relaxation ratio setpoint PR t , sp thus determined, within of the block 25 and, if applicable, of the block 24.
• the determination of the position setpoint ⁇ sp of the bypass actuator 15, 16 as a function of the trigger ratio setpoint PR t , sp uses an actuator model inverse, located in block 25. This model of reverse actuator reused several times, will be detailed later.
• the relaxation ratio set point PR t , sp is advantageously saturated, before application of the inverse actuator model 25.
• This saturation is advantageously achieved by limiting said expansion ratio PR t , sp by a rate expansion pressure PR t , S p, ma ⁇ maximum, calculated as a function of a maximum pressure P dt , m a ⁇ allowed downstream of the turbine 2, 12, according to the formula:
• the intermediate relaxation rate reference PR t , sp is determined by adding, by the adder 23, a setpoint of expansion rate PR t , sp , oi in open loop and a relaxation rate reference PR t , sp , ci in closed loop.
• the open-loop expansion rate command PR t , sp , oi is calculated as a function of the compression ratio setpoint PR c , sP by a module that models the system 20. This so-called prepositioning module, implemented in block 21, reused several times, will be detailed later.
• the closed loop expansion rate command PR t , sp , c i uses a loopback on measured or estimated quantities from the system 20 to control the process. It is calculated as a function of an error or deviation ⁇ PRc between the compression ratio setpoint PR c , sp and the measurement of the compression ratio PR c , m actually produced. The calculation is performed by a first controller module 22. This controller module, implemented in block 22, reused several times, will be detailed later.
• the ⁇ sp position setpoint of the actuator of the bypass 15, 16 is determined by adding by the adder 29, a position setpoint ⁇ sp, i o in open loop and a position command ⁇ sp , c i closed loop.
• the closed loop position command ⁇ sp , c i uses a loopback on measured or estimated quantities from the system 20 to control the process. It is calculated according to the error ⁇ PRc between the compression ratio setpoint PR c, sp and the compression ratio measurement PR c, m by a second controller module 27. This controller module, implemented at block 27 is very similar to the one used in the serial mode.
• the open-loop position command ⁇ sp , o i is calculated as a function of the compression ratio setpoint PR C; Sp by a module modeling the system 20.
• This module comprises in sequence a prepositioning module 26, implemented in the block 26 and identical to the pre-positioning module 21 of the serial mode, and a model inverse actuator module, implanted at the block 28 and identical to the model module of the inverse actuator 25 of the series mode.
• the determination of the position set ⁇ sp , o i in loop open comprises the successive steps of determining a relaxation rate setpoint PR t , sp , oi open loop according to the compression ratio setpoint PR c , sp by the prepositioning module 26 and determining a position set ⁇ sp , o i in open loop as a function of the relaxation ratio setpoint PR t , sp , oi in open loop thus determined using an inverse actuator model, implemented in block 28.
• the saturation optional, performed on the magnitude of the expansion ratio PR t , sp within the block 24 of the series mode, is here carried out on the position variable ⁇ sp of the bypass actuator 15, 16, within the block 32, the larger magnitude setpoint maximum position ⁇ sp , max , corresponding to the same maximum acceptable pressure Pdt, ma ⁇ in the exhaust pipe downstream of the turbine 2, 12.
• This saturation is performed according to the formula:
• ⁇ sp sat is a position setpoint after saturation
• ⁇ sp is the position setpoint before saturation
• ⁇ sp max is a maximum position setpoint
• the maximum position setpoint ⁇ sp , max is determined as a function of the expansion ratio PR t , sp , o i in open loop using a reverse actuator model, implemented in the block
• This model of inverse actuator is identical to that implanted in block 28 and block 25 of the serial mode.
• the open-loop expansion ratio PR t , sp , o i is, prior to the application of the inverse actuator model 31, to determine the maximum position setpoint ⁇ sp , max , saturated, at block 30, as a function of the maximum pressure Pdt, ma ⁇ authorized downstream of the turbine 2, 12.
• the prepositioning module implanted at the blocks 21 and 26, determines a relaxation rate reference from the compression ratio setpoint. It is based on an assumption of equal power of the compressor and the turbine in steady state. It can break down into four stages.
• Step n ° 1 Calculation of a turbocharger speed set point
• a speed reference is calculated from a function f1, given in the form of a compressor chart f1, supplied by the manufacturer as a function of reduced or corrected quantities in pressure and temperature relative to reference values.
• This map is represented in FIGS. 6 to 9. It gives the compression ratio PR C on the wheel of the compressor 3, 13 as a function of the flow W c , m , cor corrected and the speed N sp , corc corrected relative to the compressor.
• the regime N being defined indifferently for the turbine 2, 12 or the compressor 3, 13 can be corrected N sp , cort relative to the temperature T ut of the turbine 2, 12 or corrected N sp , corc relative to the temperature T uc compressor 3, 13.
• the flow rate W c , m , intake air horn 5 is obtained by the above formula as a function of the flow rate W c , m , air horn .
• This flow W c , m , cor is for example measured by a flow meter 9. Hypothesis is made that the flow through the compressor 13 low pressure is identical to the flow rate through the compressor 3 high pressure.
• the setpoint N sp of turbocharger speed is thus obtained as a function of the compression ratio setpoint PR c , sp and the flow rate W c , m by inverting the function f1.
• Step 2 Calculation of the compressor power setpoint.
• the power H c of the compressor 3, 13 is expressed analytically by applying the fundamental principle of thermodynamics to the wheel of the compressor 3, 13. This results in an expression showing the pressure conditions at the terminals of the compressor 3, 13, the flow rate W c , m through it and the temperature T uc upstream:
• the yield ⁇ c in the previous expression is related to the regime N sp and to the flow rate W c , m .
• This relation is given by a function f2, established by the constructor, for example in the form of a map f2. Such mapping is shown in Figures 10 to 13.
• the pressure ratio setpoint PR c , sp , the flow measurement W c , m and the setpoint speed N sp are known . It is thus possible to calculate the power setpoint H c , sp compressor.
• This power H c , sp consumed by the compressor 3, 13 corresponds to the power that must be recovered by the turbine 2, 12 and transmitted to said compressor 3, 13 to reach the supercharging pressure P dt , HP desired in the distributor of admission 6.
• Step 3 Calculate the power of the turbine.
• Step 3 transforms the power setpoint H c , sp compressor into power setpoint H t , sp turbine.
• the rotational speed or speed N of the turbocharger 1, 11 is obtained by the fundamental principle of the dynamics applied to the compound system of the turbine 2, 12, the compressor 3, 13 and the axis of coupling between turbine and compressor. This relationship allows to transfer the instructions “admission” (on the compressor) in "exhaust” instructions (on the turbine).
• the N regime of the turbocharger 1, 11 depends essentially on the difference between the power H t of the turbine 2, 12 and the power H c of the compressor 3, 13. These powers are expressed analytically from the application of the first principle of thermodynamics. In the equation below, the powers are replaced by their instructions:
• Step 4 Calculation of the Open Loop Rate Setpoint
• the power H t , sp turbine is known and depends explicitly on the expansion ratio PR t , sp , according to the following formula:
• the cartography F integrates the cartographies f3 and f4
• An example of such mapping F "1 is illustrated in Figures 14 to 17.
• thermodynamic constants Cp t thermal capacity of the exhaust gas 7 at constant pressure is equal to 1136 J / kg / K
• Cp c thermal capacity of the intake air 5 at constant pressure is equal to 1005 J / kg / K
• T ut upstream of the turbine can be known by mapping according to the engine speed
• T c , ref 298 ° K
• T t , f e 873 ° K
• the controller is another reused module in the various embodiments.
• a first controller module is another reused module in the various embodiments.
• a second controller module 27 is used by the parallel mode.
• the function of such a regulator is, in known manner, to modify a output quantity, here PR t , sp or ⁇ sp , in order to cancel the difference ⁇ PRc measured at the input.
• the controller is a regulator 22, 27 using fuzzy logic rules.
• the regulator 22, 27 may comprise a Proportional, Integral, Derived or PID module.
• Another module reused in the various embodiments is a module modeling a bypass actuator 15, 16.
• Such an actuator placed in a manifold is controllable proportionally by a setpoint ⁇ sp in order to modify the section of S act from its opening. between 0 and 100%.
• Such modeling is for example obtained using an equation of Barré Saint Venant, according to the formula:
• PR denotes the input quantity is respectively: PR t , S p the reference rate of relaxation,
• PRt, sp where the open loop expansion ratio setpoint, PRt, sp, oi, sat the saturated open loop expansion ratio setpoint
• W act is a flow through the actuator 15, 16 S act is a section of the actuator 15, 16, P dt is a pressure measurement downstream of the turbine, T dt is a temperature measurement downstream of the turbine, ⁇ a function of the variable X, defined by:
• Y t is a first thermodynamic constant of the exhaust gas (7), equal to 1.4
• R is the gas constant, equal to 287 J / kg / K.
• W t , s p is a flow setpoint through the turbine 2
• said section can be mapped as a function of the position command ⁇ sp of said actuator 15, 16 and of the relaxation rate reference PR t , sp .
• a double turbocharger as shown in Figure 2, comprising a first high pressure turbocharger 1 comprising a turbine 2 driven high pressure by the exhaust gas 7 from the heat engine 4, a high pressure compressor 3 driven in rotation by the high pressure turbine 2 to compress the intake air 5 injected into the heat engine 4, and a by-pass actuator.
• Such a method determines an instruction ⁇ sp , H p for controlling the high-pressure bypass actuator 15 and / or a setpoint ⁇ sp , B p for controlling the low-pressure bypass actuator 16 as a function of a report instruction of pressure PR c, sp, H high pressure p, pressure ratio setpoint PR c, sp, B p low pressure, a flow rate W c, m of air through the compressor, a temperature T uc upstream of the compressor 3, 13, a temperature T ut upstream of the turbine 2, 12.
• FIG. 5 One embodiment of such a method is illustrated in FIG. 5.
• a manager 19 arbitrates between two independent loops, each dedicated to the control of one of the turbochargers 1, 11 by means of its bypass actuator. respectively the high pressure bypass actuator and the low pressure bypass actuator 16. Only one of the two turbochargers 1, 11, determined by the manager 19, is driven at a time.
• the manager 19 determines the necessary inputs and is the position setpoint ⁇ sp , H p of the high pressure bypass actuator as a function of a compression ratio setpoint PR C , SP , HP high pressure and a compression ratio measurement PR c , m , high pressure H p if the high pressure turbocharger 1 is controlled, or the position set ⁇ sp , B p of the low pressure bypass actuator 16 as a function of a compression ratio setpoint PR c, sp, low pressure p B and a compression ratio measurement PR c, m, p B low pressure if the low-pressure turbocharger 11 is driven.
• Each of these two position commands ⁇ sp , H p, ⁇ sp , B p is determined according to one of the embodiments of the previously described method.
• the manager 19 determines which high pressure turbocharger 1 or low pressure 11 is controlled. Depending on the case, it receives either a position set ⁇ sp , H p high pressure determined by a high pressure module 17, or a position set ⁇ sp , BP low pressure determined by a low pressure module 18.
• the driver 19 drives the high-pressure actuator 15 by the setpoint ⁇ sp , H p, controls the low-pressure actuator 16 in the closed position by a command ⁇ sp , BP at 0%, and commands the high pressure valve 14 in the closed position by a control
• the driver 19 drives the low-pressure actuator 16 by the setpoint ⁇ sp , BP, controls the high-pressure actuator 15 in the open position by a command ⁇ sp , H p to 100%, and controls the high pressure valve 14 in the open position by a control ⁇ .
• the nominal or measurement input variables PR c , sp , H p, PRc, m, HP, PRC, S P , BP and PR c , m , B p are optionally shaped by an input block 35 from more basic quantities such as pressures.
• the main setpoint is a supercharging pressure or pressure P dc , sP , HP downstream of the compressor 3 high pressure.
• the measurement of this same magnitude Pdc, m, HP still noted Pdc, HP is also available measured or estimated from the controlled system 20.
• the pressure measurement P U c, m, HP still noted P UC , HP upstream of the high pressure compressor 3 is still available by measurement or estimation. This makes it possible to calculate the input quantities of the high-pressure module 17:
• the other useful quantities W c , m , HP , Pdt, HP, Pdc, HP, T ut , H p, T uc , H p are obtained by a sensor, an estimator or a cartography.
• the bypass valve compressor 14 When driving the turbocharger 11 low pressure, the bypass valve compressor 14 is open.
• the downstream pressure P dc , sP , low pressure BP is then equal to the supercharging pressure or downstream pressure Pdc, s P , high pressure HP which is known.
• Pdc, m, BP Pdc, m, HP-
• the upstream pressure P U c, m, BP low pressure is equal to the air intake pressure 5 is the atmospheric pressure P atm equal to 1 atm. This makes it possible to calculate the input quantities of the low-pressure module 18:
• the other useful quantities W c , m , B p, Pdt, BP, Pdc, BP, T ut , BP, T uc , B p are obtained by a sensor, an estimator or a cartography.
• the turbocharger selection step 1, 11 is carried out by the manager 19 according to the following rules: the high pressure turbocharger 1 via the high pressure bypass actuator is controlled when the engine RM 4 speed is less than a threshold, the bypass valve 14 of the high pressure compressor 3 being controlled closed and the low pressure bypass actuator 16 being controlled closed, - the low pressure turbocharger 11 via the low pressure bypass actuator 16 is piloted when the speed of the engine 4 is greater than a threshold, the bypass valve 14 of the high pressure compressor 3 being controlled open and the high pressure bypass actuator being controlled open.
• the engine speed threshold 4 is for example equal to 2750 rpm.
• a more advanced high pressure / low pressure switching strategy taking into account for example the load can still be used.
• a hysteresis can advantageously be introduced in order to avoid too frequent switching around the engine speed threshold.
• the results obtained with the method according to the invention are illustrated in the curves of FIGS. 18 and 19. All the curves show the boost pressure as a function of time during a transient, here a charge with a gear ratio. three.
• the reference / base corresponds to the double-loop process of the prior art.
• Curve 36 shows the boost pressure setpoint Pdc, s P , HP for the reference.
• Curve 37 shows the supercharging pressure setpoint P dc , sP , HP for the series mode.
• the Curve 38 shows the boost pressure measurement Pdc, m, HP for the reference.
• Curve 39 is the supercharging pressure measurement P dc , m, HP for the series mode.
• Curve 40 shows the boost pressure setpoint Pdc, s P , HP for the reference.
• Curve 41 shows the supercharging pressure setpoint P dc , sP , HP for the parallel mode.
• Curve 42 is the boost pressure measurement Pdc, m, HP for the reference.
• Curve 43 FIG boost pressure measurement P dc, m, HP for the parallel mode. The method presented shows that the regulation of a double stage supercharging system is possible without taking into account the measurement of the pressure in the exhaust manifold 8 of the engine 4.
• the "single loop” series and parallel structures have performance very close to each other.
• the "single loop” structures make it possible to obtain response times that are virtually identical to those obtained with the "double loop” reference method.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Supercharger (AREA)

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• 2009
  • 2009-03-30 FR FR0951992A patent/FR2943727A1/fr active Pending
• 2010
  • 2010-02-11 KR KR1020117025787A patent/KR20120006525A/ko not_active Application Discontinuation
  • 2010-02-11 WO PCT/FR2010/050234 patent/WO2010112718A1/fr active Application Filing
  • 2010-02-11 CN CN201080023128.XA patent/CN102449290B/zh not_active Expired - Fee Related
  • 2010-02-11 US US13/262,404 patent/US8931271B2/en not_active Expired - Fee Related
  • 2010-02-11 EP EP10708331A patent/EP2414657A1/de not_active Withdrawn

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