CN104343547B - The control method and device of valve stroke - Google Patents
The control method and device of valve stroke Download PDFInfo
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- CN104343547B CN104343547B CN201310329511.3A CN201310329511A CN104343547B CN 104343547 B CN104343547 B CN 104343547B CN 201310329511 A CN201310329511 A CN 201310329511A CN 104343547 B CN104343547 B CN 104343547B
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Abstract
The present invention relates to automotive electronic technology, valve stroke method of adjustment more particularly to based on permagnetic synchronous motor and the valve stroke control device of the above method is realized.Include permagnetic synchronous motor according to valve stroke control device of the invention, microcontroller, the signal interface circuit and drive circuit coupled with microcontroller, the microcontroller controls the rotation of the permagnetic synchronous motor to arrive desired value corresponding with accelerator pedal position signal with by valve stroke regulation by the drive circuit, wherein, the microcontroller is to the control of the rotation of the permagnetic synchronous motor based on the motor position signal received through the signal interface circuit, motor current signal and the signal relevant with valve capacity, the motor position signal is provided by the rotary transformer being equipped with the permagnetic synchronous motor.
Description
Invention field
The present invention relates to automotive electronic technology, valve stroke method of adjustment more particularly to based on permagnetic synchronous motor and
Realize the valve stroke control device of the above method.
Background technology
Engine variable valve lift technology can provide the gas of matching when engine is with different rotating speeds and load operation
Door lift.For example under low speed, low load condition, the valve stroke of lift range variable technology selection of small so that strengthen into
Gas eddy intensity of flow, increases turbulent flow in cylinder, improves burning velocity, improves cold start-up and reduces oil consumption；And in high speed, higher load condition
Under, lift range variable technology then by increasing valve stroke, reduces valve throttling loss, significantly improves air inflow, so that
Improve the power output of engine and reduce fuel consumption.In a word, it is lifting engine by lift range variable technology
The key technology of dynamic property, economy, emission performance and ride comfort level.
Existing gasoline engine variable valve lift system adjusts valve stroke using brushed DC motor as power source.Figure
1 shows a kind of mechanical structure schematic diagram of typical valve stroke control device.In the construction shown in fig. 1, brushed DC
Motor drives eccentric shaft turns, eccentric cam 1 to act on intermediate bar 3 through rocking arm 2, make intermediate bar by turbine and worm decelerator
3 pivot position changes, so as to change the lift of valve indirectly.But the use of brushed DC motor is present is permitted
Many shortcomings, such as Service Life of Carbon Brush are short, electromagnetic noise is big etc. when needing periodic maintenance and motor rotation.On the other hand, it is
The current location of detection eccentricity control axle, it is necessary in the eccentricity control shaft end of brushed DC motor install rotary angle transmitter additional, should
The signal of sensor detection is input into regulation process of the microcontroller for valve stroke as feedback signal.But this non-connect
Touch rotary angle transmitter needs installation accuracy higher, and its is expensive.More thorny, rotary angle transmitter once loses
Effect, will certainly cause the collapse of whole valve lift control system.
The content of the invention
It is an object of the present invention to provide a kind of valve stroke control device, it passes through to be substituted using permagnetic synchronous motor
Brushed DC motor, effectively overcomes disadvantages mentioned above.
According to one embodiment of the present of invention, valve stroke control device includes permagnetic synchronous motor, microcontroller and micro-
The signal interface circuit and drive circuit of controller coupling, the microcontroller control the permanent magnetism by the drive circuit
The rotation of synchronous motor arrives desired value corresponding with accelerator pedal position signal with by valve stroke regulation, wherein, the micro-control
Device processed is to the control of the rotation of the permagnetic synchronous motor based on motor position signal, the electricity received through the signal interface circuit
Machine current signal and the signal relevant with valve capacity, the motor position signal are equipped with by the permagnetic synchronous motor
Rotary transformer provide.
In the above-described embodiments.Because permagnetic synchronous motor carries rotary transformer, therefore rotary angle transmitter can be saved,
This greatly reduces system cost.
Preferably, in above-mentioned valve stroke control device, the signal relevant with air inflow is near inlet manifold
Air flow rate signal, and the microcontroller to judge whether valve stroke is adjusted according to the air flow rate signal described
Desired value.
Preferably, in above-mentioned valve stroke control device, the signal relevant with valve capacity is inlet manifold
Oxygen concentration signal near neighbouring air flow rate signal and blast pipe, and the microcontroller believes according to the air mass flow
Number and oxygen concentration signal judge whether valve stroke adjusts the desired value.
Preferably, it is described when judging that valve stroke is not up to the desired value in above-mentioned valve stroke control device
Microcontroller controls the rotation of the permagnetic synchronous motor as follows：
Proportion of utilization integral adjustment algorithm determines the operational factor of the permagnetic synchronous motor, wherein, the proportional integral
It is the actual value of current of electric and the setting value of current of electric corresponding with the desired value, the reality to adjust the input quantity of algorithm
Actual value is obtained by implementing Clarke conversion and Park conversion successively to the motor position signal and the motor current signal
Arrive；
Implement inverse Park conversion and inverse Clarke conversion successively to the operational factor；
Utilization space Vector Modulation, is determined to drive institute by the operational factor after implementing inverse Park conversion and inverse Clarke conversion
State the duty cycle signals of the three-phase voltage of permagnetic synchronous motor；And
The duty cycle signals are exported to the drive circuit.
Preferably, in above-mentioned valve stroke control device, also comprising CAN communication circuit, the microcontroller is through described
CAN communication circuit and external device communication.
It is a further object to provide a kind of method that valve stroke is adjusted by permagnetic synchronous motor, it passes through
Brushed DC motor is substituted using permagnetic synchronous motor, disadvantages mentioned above is effectively overcome.
According to one embodiment of the present of invention, the method by permagnetic synchronous motor regulation valve stroke includes following step
Suddenly：
The desired value of the valve stroke is determined according to accelerator pedal position signal；
Judge whether valve stroke adjusts the desired value according to the signal relevant with valve capacity；
If it is determined that when valve stroke is not up to the desired value, then actual value according to current of electric and with the target
The setting value for being worth corresponding current of electric determines the operational factor of the permagnetic synchronous motor, wherein, the actual value is by right
The motor position signal and the motor current signal implement Clarke conversion successively and Park is converted and obtained, the motor
Position signalling is provided by the rotary transformer being equipped with the permagnetic synchronous motor；
Implement inverse Park conversion and inverse Clarke conversion successively to the operational factor；
Utilization space Vector Modulation, is determined to drive institute by the operational factor after implementing inverse Park conversion and inverse Clarke conversion
State the duty cycle signals of the three-phase voltage of permagnetic synchronous motor；And
The duty cycle signals are exported to the drive circuit.
Preferably, in the above-mentioned methods, proportion of utilization integral adjustment algorithm determines the adjusted value of current of electric.
Preferably, in the above-mentioned methods, the signal relevant with air inflow is the air mass flow letter near inlet manifold
Number.
Preferably, in the above-mentioned methods, the signal relevant with valve capacity is the air stream near inlet manifold
Oxygen concentration signal near amount signal and blast pipe.
Preferably, in the above-mentioned methods, the actual value is determined with the relation table of valve stroke by inquiring about air mass flow.
Brief description of the drawings
Fig. 1 is a kind of mechanical structure schematic diagram of typical valve stroke control device.
Fig. 2 is the structured flowchart according to the valve stroke control device of one embodiment of the invention.
Fig. 3 is the flow chart according to the valve stroke method of adjustment of another embodiment of the present invention.
Fig. 4 shows the relation curve of angle of eccentricity and valve stroke.
Fig. 5 is the relation curve for air mass flow and valve stroke.
Specific embodiment
The present invention is illustrated below with reference to Description of Drawings specific embodiment.It should be understood that these have
Body implementation method is merely exemplary, restriction effect is had no for spirit and scope of the invention.
In this manual, " coupling " one word should be understood to be included in direct transmission energy or signal between two units
Situation, or transmit the situation of energy or signal, and signal bag designated herein indirectly through one or more Unit the 3rd
Include but be not limited to the signal existed in the form of electricity, light and magnetic.In addition, "comprising" and " including " etc term represent except tool
Have has directly and beyond the unit clearly stated and step in the specification and in the claims, and technical scheme is not yet
Exclude the situation with other units and step do not stated directly or clearly.
It may also be noted that convenient to illustrate, each unit might not draw according to the ratio of their reality in accompanying drawing,
And the size of each unit and the ratio between them do not constitute limiting the scope of the present invention in accompanying drawing.
According to embodiments of the invention, valve stroke is adjusted using permagnetic synchronous motor, and by using being installed on
The rotary transformer of the output shaft end of permagnetic synchronous motor determines motor position or corner, eliminates and be installed on originally eccentric control
The rotary angle transmitter of shaft end processed.At the same time, it is related to the letter of valve capacity with utilization by comparing the desired value of valve stroke
Number actual value for determining, realizes to the stabilization of permagnetic synchronous motor and reliable control.Preferably, it is related to valve capacity
Signal for example includes but is not limited to the oxygen concentration signal near the air flow rate signal measured near inlet manifold and blast pipe.
Fig. 2 is the structured flowchart according to the valve stroke control device of one embodiment of the invention.
Valve stroke control device 20 according to the present embodiment mainly includes microcontroller（MCU）210th, drive circuit 220,
Permagnetic synchronous motor 230, signal processing circuit 240 and CAN communication circuit 250.
As shown in Fig. 2 microcontroller 210 and drive circuit 220, signal processing circuit 240 and the coupling of CAN communication circuit 250
Close, its transducing signal generation control command received according to signal processing circuit 240 is simultaneously exported to drive circuit 220, so as to borrow
Drive circuit 220 is helped to realize the control rotated to permagnetic synchronous motor 230.Preferably, control command uses the shape of pwm signal
Formula, drive circuit 220 will come from microcontroller 210 pwm signal be amplified after drive permagnetic synchronous motor 230.Micro-control
Device processed 210 is also communicated through CAN communication circuit 250 with external equipment.
In the present embodiment, transducing signal includes but is not limited to accelerator pedal position signal, motor position signal, motor mother
Line current signal and the signal relevant with valve capacity, wherein, motor position signal can be by installed in permanent magnet synchronous electric
Sensor on machine 230 is obtained, and motor bus current signal can be by the current sensor chip in drive circuit 220
（ICS）Obtain.Sensor for obtaining motor position signal can for example be mounted to the output shaft end of permagnetic synchronous motor
Rotary transformer, acquired signal can obtain the position of motor after being processed through the modulation /demodulation of signal processing circuit 240
Information.Transducing signal is supplied to microcontroller 210 after being converted to data signal through signal processing circuit 240.
In the present embodiment, in non-limiting manner, can be using ST Microelectronics's production based on Cortex-M3 kernels
STM32F103ZG processors as microcontroller 210, wherein, pin PB0, PB1, PC1 of the processor are coupled respectively to oil
Door pedal sensor, air flow sensor, motor bus current sensor, pin PE8, PE9, PE10, PE11, PE12,
PE13 is used as the control output end being connected with drive circuit 220.Additionally, STM32F103ZG processors and signal processing circuit 240
In rotary transformer decoding chip AD2S1205 between use serial communication mode, wherein, pin PD0~PD6 pins difference
SDO, SDI with rotary transformer decoding chip AD2S1205,SCLK、A0、A1、Pin is connected.
Fig. 3 is the flow chart according to the valve stroke method of adjustment of another embodiment of the present invention.For the sake of illustrating conveniently,
It is assumed here that the method that the present embodiment is realized in the valve stroke control device shown in Fig. 2.It should be noted however that this is only
Only it is exemplary, principle of the invention can be completely applied to the valve liter that other use permagnetic synchronous motor as power source
Process control device.
As shown in figure 3, in step 301, signal processing circuit 240 receives gas pedal position from accelerator pedal position sensor
Confidence number and being converted to is suitable to the form of the treatment of microprocessor 210.
Subsequently enter step 302, the desired value that microcontroller 210 determines valve stroke according to accelerator pedal position signal is simultaneously
And determine corresponding angle of eccentricity from the desired value, it is hereby achieved that permagnetic synchronous motor, electricity in d-q coordinate systems
Stream setting value idsAnd iqs。
Fig. 4 shows the relation curve of angle of eccentricity and valve stroke, and wherein abscissa is eccentricity control Shaft angle, is indulged
Coordinate is the valve stroke in units of millimeter.As illustrated, existing between angle of eccentricity and valve stroke one-to-one
Relation, therefore corresponding angle of eccentricity can be worth to the target of identified valve stroke.Due to the deceleration of worm and gear
The angle turned over than being known, therefore needed for the angle that can be turned over as eccentricity control axle extrapolates permagnetic synchronous motor.
In typical application example, eccentric shaft can continuously change in the range of 0~170 °, and valve stroke can be in the range of 0~8.93MM
Continuously adjust.
Preferably, between the relation and angle of eccentricity and valve stroke between accelerator pedal position signal and valve stroke
Relation all store in table form, therefore microcontroller 210 can by table look-up determine desired value and angle of eccentricity.
Then step 303 is performed, the rotary transformer that signal processing circuit 240 is equipped with from permagnetic synchronous motor 240 is read
Take motor position signal and be supplied to microcontroller 210.Step 304 is then performed, signal processing circuit 240 is from drive circuit
Current sensor chip in 220 reads the actual value of current of electric（Namely motor bus current signal ia、ibAnd ic）And carry
Supply microcontroller 210.
Step 305 and 306 are then performed successively, microcontroller 210 utilizes motor position signal, motor bus current is believed
Number ia、ibAnd icClarke conversion and Park conversion are implemented respectively so as to obtain the actual value i of the current of electric in d-q coordinate systemsq
And id。
In step 307, microcontroller 210 is according to current setting value idsAnd iqsWith actual value iqAnd idDetermine permanent-magnet synchronous
The operational factor of motor.In the present embodiment, for the consideration of motor control convenient to carry out, operational factor is with d-q coordinate systems
Voltage signal uqAnd udForm provide.Preferably, it is possible to use proportional integral regulation algorithm determine above-mentioned operational factor, its
In, input quantity is the actual value and setting value of current of electric.It is worthy of note that, it would however also be possible to employ other control algolithms, bag
Include but be not limited to PID regulation algorithm etc..
Step 308 and 309 are then performed successively, and microcontroller 210 is to operational factor uqAnd udInverse Clarke is implemented respectively to become
Change and inverse Park conversion is so as to obtain the voltage signal u in A-B-C coordinate systemsa、ubAnd uc.
Subsequently enter step 310, the utilization space Vector Modulation of microcontroller 210（SVPWM）Calculate permagnetic synchronous motor
Three-phase voltage dutycycle and export to drive circuit 220.Used as response, drive circuit 220 drives according to above-mentioned dutycycle
Eccentric shaft turns are changed with the pivot position for driving intermediate bar, so as to change the lift of valve.
Then, in step 311, signal processing circuit 240 is from the air flow sensor near the inlet manifold
（Such as mass air flow sensor）Receive the signal of the air mass flow on entering inlet manifold and be converted to and be suitable to microprocessor 210
The form for the treatment of.
Then step 312 is performed, microcontroller 210 judges whether valve stroke is adjusted in abovementioned steps 302 really
Fixed desired value.If it is determined that reach desired value, then into step 313, otherwise return to step 303.
Fig. 5 is the relation curve for air mass flow and valve stroke, and wherein abscissa is the valve in units of millimeter
Lift, ordinate is the air mass flow in units of liter/second.As illustrated, air mass flow and valve liter near inlet manifold
There is one-to-one relation between journey, therefore corresponding valve stroke can be determined according to air flow rate signal.
In order to further improve the reliability of system, alternatively, air flow rate signal can be simultaneously utilized in step 312
Judge whether valve stroke is adjusted to desired value with the oxygen concentration of the lambda sensor detection near blast pipe.
In step 313, whether microcontroller 210 determines experience one in advance from the previous rotation end of permagnetic synchronous motor
If time period, if it is determined that a default time period is experienced, then return to step 301, with according to new gas pedal position
Signal Regulation valve stroke is put, will otherwise be continued waiting for.
Above the present invention is illustrated by reference to specific embodiment.However, other embodiments than that described above are similarly
Ground is within the scope of the invention.Can provide within the scope of the invention and the above-mentioned method that the method is performed by hardware or software
The different method and step of step.Different qualities of the invention and step can be combined in other combinations other than the above.This
The scope of invention is only defined by the following claims.
Claims (9)
1. a kind of valve stroke control device, including the signaling interface that permagnetic synchronous motor, microcontroller are coupled with microcontroller
Circuit and drive circuit, the microcontroller control the rotation of the permagnetic synchronous motor by the drive circuit with by gas
Desired value corresponding with accelerator pedal position signal is arrived in door lift regulation, wherein, the microcontroller is to the permanent magnet synchronous electric
The control of the rotation of machine is based on the motor position signal, motor current signal that are received through the signal interface circuit and and valve
The relevant signal of air inflow, the motor position signal is provided by the rotary transformer being equipped with the permagnetic synchronous motor,
Wherein, when judging that valve stroke is not up to the desired value, the microcontroller control as follows it is described forever
The rotation of magnetic-synchro motor：
Proportion of utilization integral adjustment algorithm determines the operational factor of the permagnetic synchronous motor, wherein, the proportional integral regulation
The input quantity of algorithm is the actual value of current of electric and the setting value of current of electric corresponding with the desired value, the actual value
Obtained by implementing Clarke conversion and Park conversion successively to the motor position signal and the motor current signal；
Implement inverse Park conversion and inverse Clarke conversion successively to the operational factor；
Utilization space Vector Modulation, the operational factor after being converted by the inverse Park conversion of execution and inverse Clarke is determined described in driving forever
The duty cycle signals of the three-phase voltage of magnetic-synchro motor；And
The duty cycle signals are exported to the drive circuit.
2. valve stroke control device as claimed in claim 1, wherein, the signal relevant with valve capacity is air inlet
Air flow rate signal near manifold, and the microcontroller judges whether valve stroke is adjusted according to the air flow rate signal
Save the desired value.
3. valve stroke control device as claimed in claim 1, wherein, the signal relevant with valve capacity is air inlet
The oxygen concentration signal near air flow rate signal and blast pipe near manifold, and the microcontroller is simultaneously according to the sky
Throughput signal and oxygen concentration signal judge whether valve stroke adjusts the desired value.
4. valve stroke control device as claimed in claim 1, wherein, also comprising CAN communication circuit, the microcontroller warp
The CAN communication circuit and external device communication.
5. a kind of method that valve stroke is adjusted by permagnetic synchronous motor, comprises the following steps：
The desired value of the valve stroke is determined according to accelerator pedal position signal；
Judge whether valve stroke adjusts the desired value according to the signal relevant with valve capacity；
If it is determined that when valve stroke is not up to the desired value, then actual value according to current of electric and with the desired value pair
The setting value of the current of electric answered determines the operational factor of the permagnetic synchronous motor, wherein, the actual value is by motor
Position signalling and motor current signal implement Clarke conversion successively and Park is converted and obtained, and the motor position signal is by institute
The rotary transformer being equipped with permagnetic synchronous motor is stated to provide；
Implement inverse Park conversion and inverse Clarke conversion successively to the operational factor；
Utilization space Vector Modulation, the operational factor after being converted by the inverse Park conversion of execution and inverse Clarke is determined described in driving forever
The duty cycle signals of the three-phase voltage of magnetic-synchro motor；And
The duty cycle signals are exported to drive circuit.
6. method as claimed in claim 5, wherein, proportion of utilization integral adjustment algorithm determines the adjusted value of current of electric.
7. method as claimed in claim 5, wherein, the signal relevant with valve capacity is the sky near inlet manifold
Throughput signal.
8. method as claimed in claim 5, wherein, the signal relevant with valve capacity is the sky near inlet manifold
Oxygen concentration signal near throughput signal and blast pipe.
9. method as claimed in claim 7 or 8, wherein, determine institute with the relation table of valve stroke by inquiring about air mass flow
State actual value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310329511.3A CN104343547B (en) | 2013-07-31 | 2013-07-31 | The control method and device of valve stroke |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310329511.3A CN104343547B (en) | 2013-07-31 | 2013-07-31 | The control method and device of valve stroke |
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| Publication Number | Publication Date |
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| CN104343547A CN104343547A (en) | 2015-02-11 |
| CN104343547B true CN104343547B (en) | 2017-05-31 |
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| CN201310329511.3A Active CN104343547B (en) | 2013-07-31 | 2013-07-31 | The control method and device of valve stroke |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1851242A (en) * | 2006-04-14 | 2006-10-25 | 江门市硕普科技开发有限公司 | Engine continuous variable valve phase driving device |
| JP2007285483A (en) * | 2006-04-20 | 2007-11-01 | Denso Corp | Actuator with feed screw mechanism |
| CN101907001A (en) * | 2010-07-23 | 2010-12-08 | 高伟 | Stepless variable valve lift mechanism |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4305398B2 (en) * | 2005-02-01 | 2009-07-29 | 株式会社デンソー | Actuator of valve lift control device |
| JP4314208B2 (en) * | 2005-04-28 | 2009-08-12 | 株式会社デンソー | Actuator of valve lift control device |
-
2013
- 2013-07-31 CN CN201310329511.3A patent/CN104343547B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1851242A (en) * | 2006-04-14 | 2006-10-25 | 江门市硕普科技开发有限公司 | Engine continuous variable valve phase driving device |
| JP2007285483A (en) * | 2006-04-20 | 2007-11-01 | Denso Corp | Actuator with feed screw mechanism |
| CN101907001A (en) * | 2010-07-23 | 2010-12-08 | 高伟 | Stepless variable valve lift mechanism |
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| CN104343547A (en) | 2015-02-11 |
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