CN106958550A - VCR engine crankshaft connecting rod hydraulic control systems and its control method - Google Patents
VCR engine crankshaft connecting rod hydraulic control systems and its control method Download PDFInfo
- Publication number
- CN106958550A CN106958550A CN201710351403.4A CN201710351403A CN106958550A CN 106958550 A CN106958550 A CN 106958550A CN 201710351403 A CN201710351403 A CN 201710351403A CN 106958550 A CN106958550 A CN 106958550A
- Authority
- CN
- China
- Prior art keywords
- cylinder
- connecting rod
- vcr
- oil
- rod hydraulic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/003—Systems with load-holding valves
-
- 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
- F02B75/00—Other engines
- F02B75/04—Engines with variable distances between pistons at top dead-centre positions and cylinder heads
- F02B75/045—Engines with variable distances between pistons at top dead-centre positions and cylinder heads by means of a variable connecting rod length
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D15/00—Varying compression ratio
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
- F15B1/02—Installations or systems with accumulators
- F15B1/021—Installations or systems with accumulators used for damping
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/161—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load
- F15B11/165—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors with sensing of servomotor demand or load for adjusting the pump output or bypass in response to demand
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/02—Servomotor systems with programme control derived from a store or timing device; Control devices therefor
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06N—COMPUTING ARRANGEMENTS BASED ON SPECIFIC COMPUTATIONAL MODELS
- G06N3/00—Computing arrangements based on biological models
- G06N3/02—Neural networks
- G06N3/08—Learning methods
- G06N3/084—Backpropagation, e.g. using gradient descent
-
- 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
- F02D2200/04—Engine intake system parameters
- F02D2200/0404—Throttle position
-
- 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
- F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
- F02D2200/101—Engine speed
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D2700/00—Mechanical control of speed or power of a single cylinder piston engine
- F02D2700/03—Controlling by changing the compression ratio
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Theoretical Computer Science (AREA)
- Biophysics (AREA)
- Evolutionary Computation (AREA)
- Artificial Intelligence (AREA)
- Biomedical Technology (AREA)
- Health & Medical Sciences (AREA)
- Computational Linguistics (AREA)
- Data Mining & Analysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Molecular Biology (AREA)
- Computing Systems (AREA)
- General Physics & Mathematics (AREA)
- Mathematical Physics (AREA)
- Software Systems (AREA)
- Analytical Chemistry (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
Abstract
The invention discloses a kind of VCR engine crankshafts connecting rod hydraulic control system, including VCR connecting rods hydraulic cylinder, the first oil circuit and the second oil circuit, one end of first oil circuit is connected with the rodless cavity of VCR connecting rod hydraulic cylinders, the other end is connected by the first hydraulically-controlled one-way valve with the left position hydraulic circuit of servo valve；One end of second oil circuit is connected with the rod chamber of VCR connecting rod hydraulic cylinders, the other end is connected by the second hydraulically-controlled one-way valve with the right position hydraulic circuit of servo valve；The servo valve is connected by Variable plunger pump with fuel tank；The VCR engine crankshaft connecting rod hydraulic control systems that the present invention is provided, can realize the precise control being switched fast with position in oil circuit direction；Meanwhile, the present invention also provides a kind of VCR engine crankshafts connecting rod hydraulic control method.
Description
Technical field
The present invention relates to VCR field of engine control, more particularly to a kind of VCR engine crankshafts connecting rod hydraulic control system
And its control method.
Background technology
The core of VCR (Variable Compression Ratio, variable compression ratio) technology is：According to the fortune of engine
Row operating mode dynamically adjusts the compression ratio for starting cylinder, and in running on the lower load, engine keeps higher compression ratio, so may be used
To improve fuel economy and reduction exhaust emissions；And engine uses relatively low compression ratio in high load capacity operating mode, to prevent
The rough combustion of engine, improves the reliability of engine.As the raising most potential technology of Fuel Economy,
Very big concern of the VCR technologies by domestic and international educational circles and business circles.The existing engine for realizing alterable compression ratio, be typically all
Compression ratio is adjusted by way of piston stroke, the problem of existing is：Mechanical device knot for regulating piston stroke
Structure is complicated, part is numerous, because engine is very high for the requirement of structural stability, therefore causes this kind of VCR engines to be made
High price is expensive；Because compression ratio controlling mechanism is complex, along with the real-time responsiveness of mechanical device is inherently relatively slow, cause existing
Some VCR engines are difficult to tackle the demand for control under the conditions of engine sudden load, and control effect is poor, and due to reality
Very frequently, mechanical device is more easy to wear for engine operating condition change in operation；Meanwhile, also there is adjustable state Finite in mechanical device
The problem of.
In order to solve the above technical problems, the B of Chinese invention patent CN 103670729 disclose a kind of variable link-type VCR
Connecting rod in engine link mechanism, linkage is realized using a piston structure stretched by hydraulic control, by adjusting liquid
Press to adjust the length of connecting rod, so as to play the purpose that dynamic changes compression ratio, it provides a kind of new compression ratio adjustment hand
Section, adjustable state is versatile and flexible, and regulation action response is very fast, it is not necessary to which complicated mechanical driving device, structure is relatively simple,
Cost is relatively low.
The requirement analysis of hydraulic system is compared according to variable compressive, it is desirable to hydraulic system have higher location accuracy and
Fast-response, therefore Bit andits control is the key problem of the hydraulic system, while the station keeping of the hydraulic system is also needed
Reliably to ensure, and not yet have the hydraulic control for meeting the demand and control method in the prior art.
The content of the invention
In view of this, it is an object of the invention to provide a kind of VCR engine crankshafts connecting rod hydraulic control system, Neng Goushi
The precise control being switched fast with position in existing oil circuit direction；Meanwhile, the present invention also provides a kind of VCR engine crankshafts connecting rod liquid
Press control method.
The VCR engine crankshaft connecting rod hydraulic control systems of the present invention, including VCR connecting rods hydraulic cylinder, the first oil circuit and the
Two oil circuits, one end of first oil circuit is connected with the rodless cavity of VCR connecting rod hydraulic cylinders, the other end passes through the first hydraulically-controlled one-way valve
It is connected with the left position hydraulic circuit of servo valve；One end of second oil circuit is connected with the rod chamber of VCR connecting rod hydraulic cylinders, another
End is connected by the second hydraulically-controlled one-way valve with the right position hydraulic circuit of servo valve；The servo valve passes through Variable plunger pump and fuel tank
It is connected；
The system also includes controller, the engine speed sensor for gathering engine speed information, for gathering
The TPS of throttle position information, the displacement transducer for gathering connecting rod position information, for gathering VCR
The cylinder temperature sensor of connecting rod hydraulic cylinder cylinder temperature, the in-cylinder pressure biography for gathering VCR connecting rod hydraulic cylinder in-cylinder pressures
Sensor, for gathering outside VCR connecting rod hydraulic cylinders outside the cylinder of temperature temperature sensor and for gathering outside VCR connecting rod hydraulic cylinders
The cylinder external pressure sensor of pressure；The engine speed sensor, TPS, displacement transducer, temperature in cylinder
Spend the signal output part of the outer temperature sensor of sensor, in-cylinder pressure sensor, cylinder and cylinder external pressure sensor and controller
Signal input part be connected, the servo valve, the first hydraulically-controlled one-way valve, the second hydraulically-controlled one-way valve and Variable plunger pump signal it is defeated
Enter end with the signal output part of controller to be connected.
Further, accumulator is provided between the servo valve and the first hydraulically-controlled one-way valve, the second hydraulically-controlled one-way valve.
Further, the controller is STM32F103C8T6 type single-chip microcomputers.
The VCR engine crankshaft connecting rod hydraulic methods of the present invention, comprise the following steps：
Step 1: according to engine speed sensor and TPS, the operating mode of automobile is determined, according to difference
Operating mode select corresponding compression ratio, determine the displacement of targets variable quantity x of connecting rod1；
Step 2: according to the displacement of targets variable quantity x of connecting rod1With the current displacement x of connecting rod2, draw corresponding change in displacement
Measure ΔxWith cylinder inner fluid target volume variable quantity V1；α x=x1-x2If, Δx＞ 0 then carries out oil-feed flow, if Δx＜ 0 is then carried out
Fuel-displaced flow；
Step 3: the cylinder temperature T measured by cylinder temperature sensor and in-cylinder pressure sensor1With in-cylinder pressure P1,
By T1、P1, draw corresponding cylinder inner fluid density p1；By cylinder inner fluid volume change V1With cylinder inner fluid density p1, draw into
Oil/go out oil quality m；
Step 4: measuring temperature T outside cylinder by temperature sensor outside cylinder and cylinder external pressure sensor2With cylinder external pressure P2；By
T2、P2, draw the outer fluid density p of corresponding cylinder2；By oil-feed/go out fluid density p outside oil quality m and cylinder2, draw the outer oil-feed of cylinder/
Go out oil volume V2；
Step 5: according to oil-feed outside cylinder/go out oil volume V2Size, select the servo valve control voltage U of high/low gear1/
U2, and draw oil-feed/t of fuel-displaced time, and then the volume of oil-feed/fuel-displaced is controlled, carry out oil-feed/fuel-displaced operation；
Step 6: after the completion of oil-feed/fuel-displaced operation, according to the signal of displacement transducer and according to the place of position feedback system
Reason, obtains actual connecting rod displacement x, and then draws actual cylinder inner fluid volume change V, and actual cylinder inner fluid is drawn according to m, V
Density p；
Step 7: according to cylinder inner fluid target volume variable quantity V1With actual cylinder inner fluid volume change V, fluid is obtained
Volume Changes difference DELTA V；
If Step 8: Δ V ＞ 5 × 10-5Ml, then Δ V re-start step 2 as cylinder inner fluid target volume variable quantity
To step 7；If Δ V≤5 × 10-5Ml, then terminate.
Further, in step one, the displacement of targets variable quantity x of connecting rod1Determine in the following manner：
As 0 ＜ ＜ ra ＜ 0.4 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 24.8, x1=-0.921mm；
As 0 ＜ ＜ ra ＜ 0.4 and n ＞ ＞ 1500rpm, compression ratio is 23.6, x1=-0.693mm；
As 0.4 ＜ ＜ ra ＜ 0.7 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 19.6, x1=0.276mm；
As 0.4 ＜ ＜ ra ＜ 0.7 and n ＞ ＞ 1500rpm, compression ratio is 18.5, x1=0.625mm；
As ra ＞ ＞ 0.7 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 17.6, x1=0.941mm；
As ra ＞ ＞ 0.7 and n ＞ ＞ 1500rpm, compression ratio is 16.9, x1=1.212mm；
Wherein, ra is the engine load determined by TPS, and n is to pass through engine speed sensor
The engine speed of determination.
Further, in step 3 and step 4, cylinder inner fluid density p1And the outer fluid density p of cylinder2Calculated by dynamic BP
Method show that the tranining database in dynamic BP algorithm includes 100 kinds of operating modes, and 100 kinds of operating modes are according to engine link work
Make the temperature and pressure corresponding to environment, each ten points of transverse and longitudinal coordinate are selected respectively and are corresponded to two-by-two identified.
Further, in step 6, dynamic BP algorithm is updated simultaneously after actual cylinder inner fluid density p is drawn
Train in point data base.
Further, in step 5, if V2>=0.05ml then selects high voltage U1If, V2＜ 0.05ml, then select low-voltage
U2。
Beneficial effects of the present invention：The VCR engine crankshaft connecting rod hydraulic control systems of the present invention, using closed-loop control system
System is realized the precise control being switched fast with position in oil circuit direction by servo valve, and two hydraulic control one-way valves of inlet and outlet of fuel channel are realized
Servo valve is in the quick locking of Median Function, impact and pressure fluctuation during accumulator mitigation commutation；
The VCR engine crankshaft connecting rod hydraulic control methods of the present invention so that hydraulic control system can be by adjusting in real time
The extended length of whole VCR engine crankshafts connecting rod changes the compression ratio of engine, engine is operated in optimum state.
Brief description of the drawings
The invention will be further described with reference to the accompanying drawings and examples：
Fig. 1 is the structural representation of the VCR engine crankshaft connecting rod hydraulic control systems of the present invention；
Fig. 2 is the theory diagram of the VCR engine crankshaft connecting rod hydraulic control systems of the present invention；
Fig. 3 is the flow chart of the VCR engine crankshaft connecting rod hydraulic control methods of the present invention；
Fig. 4 is BP algorithm density prediction result figure.
Embodiment
Embodiment one
As depicted in figs. 1 and 2：The VCR engine crankshaft connecting rod hydraulic control systems of the present embodiment, including VCR connecting rod liquid
Cylinder pressure 1, the first oil circuit 21 and the second oil circuit 22, one end of first oil circuit 21 and the rodless cavity of VCR connecting rods hydraulic cylinder 1 are (i.e.
Connecting rod not lower cavity) be connected, the other end left position hydraulic circuit phase that passes through the first hydraulically-controlled one-way valve 31 and servo valve 4
Even；One end of second oil circuit 22 is connected, separately with the rod chamber (the top cavity volume i.e. where connecting rod) of VCR connecting rods hydraulic cylinder 1
One end is connected by the second hydraulically-controlled one-way valve 32 with the right position hydraulic circuit of servo valve 4；The servo valve 4 passes through Variable plunger pump
5 are connected with fuel tank 6；
The system also includes controller 71, the engine speed sensor 72 for gathering engine speed information, is used for
Gather the TPS 73, the displacement transducer 74 for gathering connecting rod position information, use of throttle position information
In collection the cylinder temperature of VCR connecting rods hydraulic cylinder 1 cylinder temperature sensor 75, for gathering the in-cylinder pressure of VCR connecting rods hydraulic cylinder 1
In-cylinder pressure sensor 76, for gathering outside the cylinder of VCR connecting rods hydraulic cylinder 1 outside the cylinder of temperature temperature sensor 77 and for gathering
The cylinder external pressure sensor 78 of the cylinder external pressure of VCR connecting rods hydraulic cylinder 1；The engine speed sensor 72, throttle position are passed
Outside the outer temperature sensor 77 of sensor 73, displacement transducer 74, cylinder temperature sensor 75, in-cylinder pressure sensor 76, cylinder and cylinder
Signal input part of the signal output part of pressure sensor 78 with controller 71 is connected, and the servo valve 4, the first hydraulic pressure are unidirectional
Signal output part of the signal input part of valve 31, the second hydraulically-controlled one-way valve 32 and Variable plunger pump 5 with controller 71 is connected.
The operation principle of the hydraulic control system is：The piston rod of VCR connecting rods hydraulic cylinder 1 stretches out, when needing to become big compression ratio
When, controller 71 determines the piston rod elongation under the operating mode by numerical computations and corresponding control strategy, and controller 71 is sent out
Go out and stretch out signal, system starts fuel feeding, servo valve 4 is started working under the control electric current that controller 71 is sent, and 1YA obtains electric, watches
Take 4 left hydraulic circuits of valve open-minded, the first fluid-control one-way valve deblocking, the elongation of VCR connecting rods；Meanwhile, displacement transducer 74 works, will
The connecting rod position signal measured in real time feeds back to controller 71, and controller 71 sends instruction control servo valve 4 by computing again
Openings of sizes so as to control the uninterrupted of hydraulic oil, finally ensure that the actual overhang of connecting rod, with requiring that overhang is identical, reaches
To the requirement of precise control connecting rod position；Reach after desired location, the fast break of servo valve 4 returns to middle position, and Variable plunger pump 5 is unloaded
Lotus, the first hydraulic control one-way valve locking keeps the position of connecting rod constant.Fluid stream during the stretching of the connecting rod of VCR connecting rods hydraulic cylinder 1
Emotionally condition is：
In-line：5 → servo valve of Variable plunger pump 4 (left position hydraulic circuit) → the first hydraulic control one-way valve → VCR connecting rod liquid
The rodless cavity of cylinder pressure 1；
Oil return line：The rod chamber of VCR connecting rods hydraulic cylinder 1 → the second hydraulic control one-way valve → servo valve 4 (left position hydraulic circuit) →
Fuel tank 6.
When the connecting rod of VCR connecting rods hydraulic cylinder 1 is retracted, similarly, pressed when controller 71 show that needs reduce according to engine operating condition
Contracting than when, controller 71 sends signal, and servo valve 42YA obtains electric, and the right position hydraulic circuit of servo valve 4 is open-minded, the second fluid-control one-way
Valve deblocking, connecting rod bounces back in the presence of hydraulic coupling, and fluid mobility status is during being somebody's turn to do：
In-line：5 → servo valve of Variable plunger pump 4 (right position hydraulic circuit) → the second hydraulic control one-way valve → VCR connecting rod liquid
The rod chamber of cylinder pressure 1；
Oil return line：The rodless cavity of VCR connecting rods hydraulic cylinder 1 → the first hydraulic control one-way valve → servo valve 4 (right position hydraulic circuit) →
Fuel tank 6.
In the present embodiment, accumulation of energy is provided between the hydraulically-controlled one-way valve 31 of servo valve 4 and first, the second hydraulically-controlled one-way valve 32
Device；The pressure energy of working media can be converted into other form of energy such as potential energy, and the energy stored by accumulator
Conversion；It is that compression energy or potential energy are stored to be in due course the energy conversion in accumulator system, when system needs,
Compression energy or potential energy are changed into the energy such as hydraulic pressure or air pressure again and discharged, feed system is mended again；When system instantaneous pressure
During increase, accumulator absorbs the energy of this part, normal to ensure whole system pressure.
In the present embodiment, the controller 71 is STM32F103C8T6 type single-chip microcomputers；STM32F103C8T6 is by meaning method
32 microcontrollers 71 for belonging to enhancing train type of semiconductor company's production, are a function more powerful processing cores
Piece, it can realize the functions such as signal acquisition, the processing needed for the design system.
Power supply provides electric energy to whole control system circuit, is a highly important ring, its operating circuit in whole system
Design vital effect is played to instrument stabilizer operation, if the unstable system that is likely to result in of power supply can not normal work
Make, the serious chip that even burns out triggers accident；Therefore, the different components how power supply is effectively distributed to system seem all the more
It is important；Power circuit design is main to be considered to use which type of power supply apparatus, input and output voltage, output current and control shape
State.The power source of the hydraulic control circuit of the system is in vehicle electronics 12V electric power supply control systems, by fixed output three-terminal voltage-stabilizing
Device MC78M05 is by voltage voltage stabilizing in 5V；3.3V voltages are produced using AMS1117, and the characteristics of its is maximum is easy to use, Er Qiexing
Valency directly exports 3.3V than high, input voltage 5V~12V.
During coherent signal input and output, the signal that can be collected sensor by specific modulate circuit
It is converted into corresponding voltage signal；Then, it is by the analog/digital conversion circuit conversion built in main control chip STM32F103C8T6
Digital quantity signal, the input signal of single-chip microcomputer is used as using this signal；The signal conditioning circuit of input signal is all used by double computings
The voltage follower that amplifier LMV258 is constituted, to increase the stability of voltage acquisition signal, while improving load capacity.
Embodiment two
The VCR engine crankshaft connecting rod hydraulic methods of the present embodiment, comprise the following steps：
Step 1: according to engine speed sensor 72 and TPS 73, the operating mode of automobile is determined, according to
Different operating modes selects corresponding compression ratio, determines the displacement of targets variable quantity x of connecting rod1；
Step 2: according to the displacement of targets variable quantity x of connecting rod1With the current displacement x of connecting rod2, draw corresponding change in displacement
Measure ΔxWith cylinder inner fluid target volume variable quantity V1；Δ x=x1-x2If, Δx＞ 0 then carries out oil-feed flow, if Δx＜ 0 then enters
The fuel-displaced flow of row；
Step 3: the cylinder temperature T measured by cylinder temperature sensor 75 and in-cylinder pressure sensor 761With cylinder internal pressure
Power P1, by T1、P1, draw corresponding cylinder inner fluid density p1；By cylinder inner fluid volume change V1With cylinder inner fluid density p1, obtain
Go out oil-feed/go out oil quality m；
Step 4: measuring temperature T outside cylinder by temperature sensor outside cylinder 77 and cylinder external pressure sensor 782With cylinder external pressure
P2；By T2、P2, draw the outer fluid density p of corresponding cylinder2；By oil-feed/go out fluid density p outside oil quality m and cylinder2, draw and enter outside cylinder
Oil/go out oil volume V2；
Step 5: according to oil-feed outside cylinder/go out oil volume V2Size, select the control voltage U of servo valve 4 of high/low gear1/
U2, and draw oil-feed/t of fuel-displaced time, and then the volume of oil-feed/fuel-displaced is controlled, carry out oil-feed/fuel-displaced operation；
Step 6: after the completion of oil-feed/fuel-displaced operation, according to the signal of displacement transducer 74 and according to position feedback system
Processing, obtains actual connecting rod displacement x, and then draws actual cylinder inner fluid volume change V, is drawn according to m, V oily in actual cylinder
Liquid density p；
Step 7: according to cylinder inner fluid target volume variable quantity V1With actual cylinder inner fluid volume change V, fluid is obtained
Volume Changes difference DELTA V；
If Step 8: Δ V ＞ 5 × 10-5Ml, then Δ V re-start step 2 as cylinder inner fluid target volume variable quantity
To step 7；If Δ V≤5 × 10-5Ml, then terminate.
Further, in step one, the displacement of targets variable quantity x of connecting rod1Determine in the following manner：
As 0 ＜ ＜ ra ＜ 0.4 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 24.8, x1=-0.921mm；
As 0 ＜ ＜ ra ＜ 0.4 and n ＞ ＞ 1500rpm, compression ratio is 23.6, x1=-0.693mm；
As 0.4 ＜ ＜ ra ＜ 0.7 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 19.6, x1=0.276mm；
As 0.4 ＜ ＜ ra ＜ 0.7 and n ＞ ＞ 1500rpm, compression ratio is 18.5, x1=0.625mm；
As ra ＞ ＞ 0.7 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 17.6, x1=0.941mm；
As ra ＞ ＞ 0.7 and n ＞ ＞ 1500rpm, compression ratio is 16.9, x1=1.212mm；
Wherein, ra is the engine load determined by TPS 73, and n is to be sensed by engine speed
The engine speed that device 72 is determined.
Wherein, in step 3 and step 4, cylinder inner fluid density p1And the outer fluid density p of cylinder2Pass through dynamic BP algorithm
Draw, the tranining database in dynamic BP algorithm includes 100 kinds of operating modes, and 100 kinds of operating modes are worked according to engine link
Temperature and pressure corresponding to environment, selects each ten points of transverse and longitudinal coordinate and corresponds to two-by-two identified respectively.
Wherein, in step 6, the instruction of dynamic BP algorithm is updated simultaneously after actual cylinder inner fluid density p is drawn
Practice in point data base.
Wherein, in step 5, if V2>=0.05ml then selects high voltage U1If, V2＜ 0.05ml, then select low-voltage
U2。
Wherein, BP neural network is that a kind of transmission function of neurode in multilayer feedforward network, network is S types
Function, its output quantity is the continuous data between 0 to 1, and it can realize any non-linear from input layer to output layer
Mapping；The features such as there is self-organizing, self study, knowledge reasoning to information processing due to neutral net, be to non-determined regularity
System has self-adaptive features.Neutral net can utilize the training to sample to realize from the Any Nonlinear Function for being input to output
The mapping of corresponding relation, and embody the inherent law of object by setting up this mapping relations；BP neural network is by inputting
Layer, at least one hidden layer and the part of output layer three composition, each layer are made up of one or more neurodes, each layer of god
The input of preceding layer neuron is only received through node, the processing that input information has to pass through each layer neuron can just be changed into output layer
Output, i.e. input layer receives extraneous input pattern, and the node of hidden layer can only receive input layer information input, output layer
Node can only receive the information input of hidden layer.
The study of BP neural network be rely on be a kind of multitiered network " backstepping " learning algorithm.It training study by
Two processes of the forward-propagating of information and the backpropagation of error are constituted.It is incoming from input layer when information carries out forward-propagating
Data X (i), after the processing of each hidden layer node, by nonlinear transformation, from output layer output information Y (k), such as
The reality output result y (k) of fruit output layer and desired output valve t deviation are larger, then the learning process of BP neural network is just
Can be transferred to the back-propagation process of error, that is, by the error amount of output result by hidden layer to input layer successively negative side
To being propagated, error amount is shared to neurode all in each layer in communication process, and then obtains each layer neuromere
The information of point, and the foundation for correcting each neurode is used as using this information.By constantly adjusting input layer and hidden layer section
The linking intensity W of pointij, hidden layer and export node layer linking intensity TjkSo that the error of output result is gradually reduced, this
The forward-propagating and the backpropagation of error and each layer weighed value adjusting process for planting signal are carried out again and again, and eventually
So that output layer output result is consistent with the desired value initially set.The process that each layer neurode weights are constantly adjusted,
It is exactly the process of training and the study of BP neural network.
BP network structures are set up using newff functions, hidden neuron is set to 10, and output layer has a neuron.Choosing
The transmission function for selecting hidden layer and output layer neuron is respectively tensig functions and purelin functions.Needed before being trained
Set network training parameter in advance：Maximum iteration is set to 100, and learning rate is 0.1, and convergence error is 0.00004, other ginsengs
Number selection default value.The core code that the BP algorithm Matlab of hydraulic oil density model is realized is as follows：
As shown in figure 4, the density sample in training storehouse, predicts with BP algorithm and obtains density value and actual density
Precision is 97.89%, meets system design goal.
Finally illustrate, the above embodiments are merely illustrative of the technical solutions of the present invention and it is unrestricted, although with reference to compared with
The present invention is described in detail good embodiment, it will be understood by those within the art that, can be to skill of the invention
Art scheme is modified or equivalent, and without departing from the objective and scope of technical solution of the present invention, it all should cover at this
Among the right of invention.
Claims (8)
1. a kind of VCR engine crankshafts connecting rod hydraulic control system, including VCR connecting rods hydraulic cylinder, the first oil circuit and the second oil circuit,
It is characterized in that：One end of first oil circuit is connected with the rodless cavity of VCR connecting rod hydraulic cylinders, the other end passes through the first hydraulic pressure list
It is connected to valve with the left position hydraulic circuit of servo valve；One end of second oil circuit is connected with the rod chamber of VCR connecting rod hydraulic cylinders,
The other end is connected by the second hydraulically-controlled one-way valve with the right position hydraulic circuit of servo valve；The servo valve by Variable plunger pump with
Fuel tank is connected；
The system also includes controller, the engine speed sensor for gathering engine speed information, for gathering solar term
The door TPS of positional information, the displacement transducer for gathering connecting rod position information, for gathering VCR connecting rods
The cylinder temperature sensor of hydraulic cylinder cylinder temperature, the in-cylinder pressure sensor for gathering VCR connecting rod hydraulic cylinder in-cylinder pressures,
For gathering outside VCR connecting rod hydraulic cylinders outside the cylinder of temperature temperature sensor and for gathering VCR connecting rod hydraulic cylinder external pressures
Cylinder external pressure sensor；The engine speed sensor, TPS, displacement transducer, cylinder temperature are passed
Letter of the signal output part of the outer temperature sensor of sensor, in-cylinder pressure sensor, cylinder and cylinder external pressure sensor with controller
Number input is connected, the servo valve, the first hydraulically-controlled one-way valve, the signal input part of the second hydraulically-controlled one-way valve and Variable plunger pump
It is connected with the signal output part of controller.
2. VCR engine crankshafts connecting rod hydraulic control system according to claim 1, it is characterised in that：The servo valve
Accumulator is provided between the first hydraulically-controlled one-way valve, the second hydraulically-controlled one-way valve.
3. VCR engine crankshafts connecting rod hydraulic control system according to claim 1, it is characterised in that：The controller
For STM32F103C8T6 type single-chip microcomputers.
4. a kind of VCR engine crankshafts connecting rod hydraulic control method, it is characterised in that comprise the following steps：
Step 1: according to engine speed sensor and TPS, the operating mode of automobile is determined, according to different works
Condition selects corresponding compression ratio, determines the displacement of targets variable quantity x of connecting rod1；
Step 2: according to the displacement of targets variable quantity x of connecting rod1With the current displacement x of connecting rod2, draw corresponding displacement variable
ΔXWith cylinder inner fluid target volume variable quantity V1；Δ x=x1-x2If, ΔX＞ 0 then carries out oil-feed flow, if ΔX＜ 0 is then carried out
Fuel-displaced flow；
Step 3: the cylinder temperature T measured by cylinder temperature sensor and in-cylinder pressure sensor1With in-cylinder pressure P1, by
T1、P1, draw corresponding cylinder inner fluid density p1；By cylinder inner fluid volume change V1With cylinder inner fluid density p1, draw oil-feed/
Go out oil quality m；
Step 4: measuring temperature T outside cylinder by temperature sensor outside cylinder and cylinder external pressure sensor2With cylinder external pressure P2；By T2、
P2, draw the outer fluid density p of corresponding cylinder2；By oil-feed/go out fluid density p outside oil quality m and cylinder2, draw the outer oil-feed of cylinder/fuel-displaced
Volume V2；
Step 5: according to oil-feed outside cylinder/go out oil volume V2Size, select the servo valve control voltage U of high/low gear1/U2, and
Draw oil-feed/t of fuel-displaced time, and then control the volume of oil-feed/fuel-displaced, carry out oil-feed/fuel-displaced operation；
Step 6: after the completion of oil-feed/fuel-displaced operation, according to the signal of displacement transducer and according to the processing of position feedback system,
Actual connecting rod displacement x is obtained, and then draws actual cylinder inner fluid volume change V, actual cylinder inner fluid density is drawn according to m, V
ρ；
Step 7: according to cylinder inner fluid target volume variable quantity V1With actual cylinder inner fluid volume change V, fluid volume is obtained
Change difference DELTA V；
If Step 8: Δ V ＞ 5 × 10-5Ml, then Δ V is as cylinder inner fluid target volume variable quantity, re-starts step 2 to step
Rapid seven；If Δ V≤5 × 10-5Ml, then terminate.
5. VCR engine crankshafts connecting rod hydraulic control method according to claim 4, it is characterised in that in step one,
The displacement of targets variable quantity x of connecting rod1Determine in the following manner：
As 0 ＜ ＜ ra ＜ 0.4 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 24.8, x1=-0.921mm；
As 0 ＜ ＜ ra ＜ ＜ 0.4 and n ＞ ＞ 1500rpm, compression ratio is 23.6, x1=-0.693mm；
As 0.4 ＜ ＜ ra ＜ 0.7 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 19.6, x1=0.276mm；
As 0.4 ＜ ＜ ra ＜ 0.7 and n ＞ ＞ 1500rpm, compression ratio is 18.5, x1=0.625mm；
As ra ＞ ＞ 0.7 and 0 ＜ ＜ n ＜ 1500rpm, compression ratio is 17.6, x1=0.941mm；
As ra ＞ ＞ 0.7 and n ＞ ＞ 1500rpm, compression ratio is 16.9, x1=1.212mm；
Wherein, ra is the engine load determined by TPS, and n is to be determined by engine speed sensor
Engine speed.
6. VCR engine crankshafts connecting rod hydraulic control method according to claim 5, it is characterised in that：In step 3 and
In step 4, cylinder inner fluid density p1And the outer fluid density p of cylinder2Drawn by dynamic BP algorithm, the training in dynamic BP algorithm
Database includes 100 kinds of operating modes, and 100 kinds of operating modes are the temperature and pressures according to corresponding to engine link working environment,
Each ten points of transverse and longitudinal coordinate are selected respectively and are corresponded to two-by-two identified.
7. VCR engine crankshafts connecting rod hydraulic control method according to claim 6, it is characterised in that：In step 6,
In the training point data base of dynamic BP algorithm is updated after drawing actual cylinder inner fluid density p simultaneously.
8. VCR engine crankshafts connecting rod hydraulic control method according to claim 4, it is characterised in that：In step 5,
If V2>=0.05ml then selects high voltage U1If, V2＜ 0.05ml, then select low-voltage U2。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710351403.4A CN106958550B (en) | 2017-05-18 | 2017-05-18 | VCR engine crankshaft connecting rod hydraulic control systems and its control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710351403.4A CN106958550B (en) | 2017-05-18 | 2017-05-18 | VCR engine crankshaft connecting rod hydraulic control systems and its control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106958550A true CN106958550A (en) | 2017-07-18 |
| CN106958550B CN106958550B (en) | 2018-04-20 |
Family
ID=59482054
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710351403.4A Expired - Fee Related CN106958550B (en) | 2017-05-18 | 2017-05-18 | VCR engine crankshaft connecting rod hydraulic control systems and its control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106958550B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111005805A (en) * | 2018-10-08 | 2020-04-14 | 伊威斯发动机***有限责任两合公司 | Length-adjustable connecting rod with hydraulic control |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1512050A (en) * | 2002-12-27 | 2004-07-14 | 日产自动车株式会社 | IC engine having variable compression ratio mechanism and its control method |
| US20070129875A1 (en) * | 2004-03-26 | 2007-06-07 | Honda Motor Co., Ltd. | Control system |
| CN101936229A (en) * | 2010-07-23 | 2011-01-05 | 高伟 | Variable volume compression ratio engine |
| CN103670729A (en) * | 2013-12-24 | 2014-03-26 | 重庆交通大学 | Variable connecting rod type VCR engine connecting rod mechanism |
| CN105626258A (en) * | 2016-03-16 | 2016-06-01 | 吉林大学 | Hydraulic-drive type variable-compression-ratio piston connection rod assembly |
-
2017
- 2017-05-18 CN CN201710351403.4A patent/CN106958550B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1512050A (en) * | 2002-12-27 | 2004-07-14 | 日产自动车株式会社 | IC engine having variable compression ratio mechanism and its control method |
| US20070129875A1 (en) * | 2004-03-26 | 2007-06-07 | Honda Motor Co., Ltd. | Control system |
| CN101936229A (en) * | 2010-07-23 | 2011-01-05 | 高伟 | Variable volume compression ratio engine |
| CN103670729A (en) * | 2013-12-24 | 2014-03-26 | 重庆交通大学 | Variable connecting rod type VCR engine connecting rod mechanism |
| CN105626258A (en) * | 2016-03-16 | 2016-06-01 | 吉林大学 | Hydraulic-drive type variable-compression-ratio piston connection rod assembly |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111005805A (en) * | 2018-10-08 | 2020-04-14 | 伊威斯发动机***有限责任两合公司 | Length-adjustable connecting rod with hydraulic control |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106958550B (en) | 2018-04-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE3833323C2 (en) | ||
| DE60131598T2 (en) | Charged internal combustion engine with improved crank mechanism | |
| CN109696836B (en) | Intelligent control method for airplane steering engine electrohydraulic servo system | |
| CN102079482B (en) | Control method and controller for crane and composite actions thereof of crane | |
| CN106006483A (en) | Self-adaptive control system and method for dynamic working conditions of forklift | |
| CN107143540A (en) | Digital load sensing hydraulic control system and method | |
| CN209244950U (en) | Double valve control cylinder mode position synchronization control devices | |
| CN101194092B (en) | Method and apparatus for controlling internal combustion engine | |
| CN201801313U (en) | Crane and controller for compound action of crane | |
| CN102787915A (en) | Diesel engine electronic speed adjusting method based on reinforced study of proportion integration differentiation (PID) controller | |
| CN106958550B (en) | VCR engine crankshaft connecting rod hydraulic control systems and its control method | |
| CN102886917A (en) | Hydraulic servo control system for efficiently improving pressing precision of powder-forming hydraulic machine | |
| CN104213997A (en) | Common rail pressure control method | |
| CN102562547B (en) | Stepless airflow regulation method for high-pressure reciprocating compressor | |
| DE102004018842A1 (en) | Variable valve actuation control for operation in height | |
| CN206958033U (en) | A kind of digital load-sensitive hydraulic control architectures | |
| CN103807236B (en) | Valve control unit loads mouth independently controls multi-cylinder assignment of traffic hydraulic system | |
| CN111673026B (en) | Online control method and control system for pressing process of forging press | |
| CN102864810B (en) | A kind of engineering machinery hydraulic energy saver and control method and excavator | |
| CN106640808A (en) | Hydraulic valve core control circuit and method | |
| CN108069348A (en) | Front handling mobile crane large arm adaptive control system | |
| CN204851824U (en) | Compound control formula variable pump | |
| CN212106422U (en) | Hydraulic valve and load sensing system | |
| CN107794968A (en) | A kind of hydraulic excavator energy-conservation control system | |
| Wang et al. | Fuzzy ignition timing control for a spark ignition engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: No. 1, Fuxing Avenue, Shuang Fu new area, Jiangjin District, Chongqing Applicant after: chongqing jiaotong university Address before: 400074 Chongqing Nan'an District University Avenue, No. 66 Applicant before: chongqing jiaotong university |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20180420 Termination date: 20210518 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |