CN112228233B - FPLG stable operation control method and system based on vibration speed signal - Google Patents
FPLG stable operation control method and system based on vibration speed signal Download PDFInfo
- Publication number
- CN112228233B CN112228233B CN202011138476.3A CN202011138476A CN112228233B CN 112228233 B CN112228233 B CN 112228233B CN 202011138476 A CN202011138476 A CN 202011138476A CN 112228233 B CN112228233 B CN 112228233B
- Authority
- CN
- China
- Prior art keywords
- starting
- displacement
- combustion
- dragging
- target
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 48
- 238000006073 displacement reaction Methods 0.000 claims abstract description 73
- 238000002485 combustion reaction Methods 0.000 claims abstract description 71
- 238000010248 power generation Methods 0.000 claims abstract description 23
- 230000008569 process Effects 0.000 claims description 25
- 230000005284 excitation Effects 0.000 claims description 13
- 238000003860 storage Methods 0.000 claims description 10
- 238000004458 analytical method Methods 0.000 claims description 8
- 238000005070 sampling Methods 0.000 claims description 8
- 230000009471 action Effects 0.000 claims description 6
- 238000004364 calculation method Methods 0.000 claims description 6
- 230000006835 compression Effects 0.000 claims description 6
- 238000007906 compression Methods 0.000 claims description 6
- 230000008859 change Effects 0.000 claims description 5
- 239000000446 fuel Substances 0.000 claims description 5
- 238000002347 injection Methods 0.000 claims description 5
- 239000007924 injection Substances 0.000 claims description 5
- 239000007921 spray Substances 0.000 claims description 3
- 230000000694 effects Effects 0.000 claims 2
- 239000004606 Fillers/Extenders Substances 0.000 abstract description 2
- 208000006011 Stroke Diseases 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 9
- 238000004590 computer program Methods 0.000 description 7
- 230000006870 function Effects 0.000 description 7
- 238000012545 processing Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 2
- 239000000567 combustion gas Substances 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D29/00—Controlling engines, such controlling being peculiar to the devices driven thereby, the devices being other than parts or accessories essential to engine operation, e.g. controlling of engines by signals external thereto
- F02D29/06—Controlling engines, such controlling being peculiar to the devices driven thereby, the devices being other than parts or accessories essential to engine operation, e.g. controlling of engines by signals external thereto peculiar to engines driving electric generators
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
The invention provides a FPLG steady operation control method and a system based on a vibration speed signal, which belong to the technical field of new energy automobile range extenders, and calculate target towing force required by a mover to move to target displacement according to target displacement and starting frequency to be met by the mover, and control ignition and starting of an engine according to starting conditions; collecting vibration speed signals after starting in real time, and calculating and describing average displacement of average indicated pressure in a cylinder; and calculating the target power generation amount of the primary stroke according to the linear relation between the average displacement and the average indicated pressure and the linear relation between the average indicated pressure and the power generation amount, and controlling the generator terminal voltage according to the target power generation amount so as to control the output current to meet the power generation requirement. According to the invention, the average indicated pressure of combustion in the cylinder is judged through the vibration speed signal, and the generated energy is controlled according to the characteristic parameters of the average indicated pressure and the vibration speed signal and the relation between the average indicated pressure and the generated energy, so that the mover of the FPLG can reach the position near the set top dead center, and stable combustion of the FPLG is realized.
Description
Technical Field
The invention relates to the technical field of new energy automobile range extenders, in particular to a FPLG stable operation control method and system based on vibration speed signals.
Background
The Free Piston Linear Generator (FPLG) converts heat energy generated by combustion of an internal combustion engine into electric energy through a motor to be output, can replace an Auxiliary Power Unit (APU) of a range-extended hybrid electric vehicle, and is an important research direction of a power system of a new energy vehicle in the future as an emerging power device.
The internal combustion engine in the FPLG system has a similar thermodynamic principle with the traditional internal combustion engine, a crank-link mechanism and a flywheel mechanism are omitted in structure, heat energy generated by combustion is converted into required energy output through a motor, and the FPLG system has various potential performance advantages of high efficiency, low oil consumption and the like. The mover in the FPLG consists of a piston connecting rod and a motor mover, and the movement of the mover mainly depends on factors such as combustion gas pressure, electromagnetic force, friction force and the like in the cylinder. Since the combustion of the internal combustion engine has cyclic variation, namely the combustion pressure is different in each cycle, and the friction force is relatively stable, the magnitude and the direction of electromagnetic force generated by each cycle motor are determined according to the actual combustion process of the engine in order to ensure that the mover can stably move and ensure the stable operation of the FPLG.
Disclosure of Invention
The invention aims to provide a control method for obtaining combustion information of an engine cylinder through rotor position and rotor surface vibration speed signals, determining a circulation target power generation amount based on the combustion quality of the engine cylinder, adjusting actual power generation according to the target power generation amount, and realizing stable operation of FPLG (floating gate type generator) so as to solve at least one technical problem in the background technology.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
in one aspect, the invention provides a FPLG steady operation control method based on a vibration speed signal, which comprises the following steps:
step S110: the rotor moves under the action of the dragging force of the linear motor, and when the movement frequency of the rotor and the top dead center position which can be reached by the rotor reach the engine starting condition, the engine is started in an ignition way;
step S120: collecting vibration speed signals of the active cell after starting in real time, and calculating and describing average displacement of average indicated pressure in the cylinder;
step S130: calculating an average indicated pressure from the average displacement;
step S140: calculating a stroke target power generation amount according to the average indicated pressure;
step S150: and controlling the generator terminal voltage according to the target generating capacity, further controlling the actual generating capacity, and realizing the stable operation of the FPLG.
Preferably, the step S110 specifically includes:
the mover is firstly dragged leftwards, and the dragging force F required by the mover to move from the middle of the stroke to the target displacement is calculated 1 According to F 1 Dragging the mover to move, judging whether the first dragging half-stroke mover can reach the target displacement, and if not, dragging the next stroke;
if the target displacement is reached, the time used in the process is recorded, the motion frequency of the stroke rotor is calculated and compared with the starting frequency, and if the starting frequency is not met, the dragging of the next stroke is continued; if so, the control system controls the engine to ignite and burn, and the starting is completed.
Preferably, when the target displacement and the movement frequency do not satisfy the starting condition, then the dragging force F required for the target displacement from the left dead center to the right is calculated 2 And feeds back to the control system, and controls the motor to provide a rightward target electromagnetic force F 2 And if the right dead point position which can be achieved by the rotor in the process does not meet the target displacement, dragging for the third time.
Preferably, if the right dead center position meets the target displacement, recording the time required from the left dead center to the right dead center, calculating whether the mover movement frequency of the stroke meets the starting frequency, if not, carrying out the third dragging, and if so, controlling the engine to ignite and burn by the control system, and finishing the starting.
Preferably, in the step S120, in combination with the differential relation between the vibration displacement and the vibration velocity, the average displacement is obtained as follows:
wherein ,S1 Representing the vibration displacement of the first point, v j The vibration speed of the j point is represented, delta t is sampling interval time, and n is the sampling point number of the selected vibration period.
Preferably, in the step S130,
according to the engine principle, the average indicated pressure can be expressed as follows:
wherein ,Vh Representing the total volume of the cylinder, p i 、p i-1 The in-cylinder pressures at the times i, i-1 are shown, V i 、V i-1 The cylinder volume at the time i, i-1;
then:
wherein ,Si 、S i-1 The cylinder vibration displacement at the time of i and i-1 are shown respectively.
In a second aspect, the FPLG steady operation control system of the present invention based on a vibration velocity signal includes:
the starting module is used for dragging the rotor to move under the action of the dragging force of the linear motor, and controlling the engine to start when the movement frequency of the rotor and the top dead center position which can be reached by the rotor reach the engine starting condition;
the first calculation module is used for collecting vibration speed signals of the active cell after starting in real time and calculating and describing average displacement of average indicated pressure in the cylinder;
the second calculation module is used for calculating average indicated pressure according to the average displacement;
the third calculation module is used for calculating the generated energy required by the stroke by utilizing the linear relation between the average indicated pressure and the generated energy;
and the control module is used for controlling the generator terminal voltage according to the target generated energy, further controlling the actual generated energy and realizing the stable operation of the FPLG.
In a third aspect, the present invention provides a non-transitory computer readable storage medium comprising instructions for performing the method as described above.
In a fourth aspect, the present invention provides an electronic device comprising a non-transitory computer readable storage medium as described above; and one or more processors capable of executing the instructions of the non-transitory computer-readable storage medium.
In a fifth aspect, the invention provides an electronic device comprising means for performing the method as described above.
The invention has the beneficial effects that: the average indicated pressure of combustion in the cylinder is judged through the vibration speed signal, and the expected generated energy can be determined according to the real-time combustion condition according to the characteristic parameters of the average indicated pressure and the vibration speed signal and the relation between the average indicated pressure and the generated energy, so that the mover of the FPLG can reach the position near the set top dead center, and stable combustion of the FPLG is realized.
Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic diagram of a mounting structure of a back-mounted FPLG steady operation control test according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a linear relationship between average indicated pressure and power generation according to an embodiment of the present invention.
FIG. 3 is a schematic diagram showing the linear relationship between the average indicated pressure and the average displacement according to the embodiment of the present invention.
FIG. 4 is a graph showing vibration velocity signal versus in-cylinder pressure for a certain operating condition according to an embodiment of the present invention.
Fig. 5 is a flowchart of a FPLG steady operation control method based on a vibration velocity signal according to an embodiment of the present invention.
Wherein: 2-a linear motor; 4-connecting flanges; 1-left cylinder; 3-right cylinder; 10-a piston; 11-connecting rod; 12-a mover; 7-a mover assembly; 5-a bracket; 6-a test bed; 8-position sensor; 9-piezoelectric vibration velocity sensor.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements throughout or elements having like or similar functionality. The embodiments described below by way of the drawings are exemplary only and should not be construed as limiting the invention.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless expressly stated otherwise, as understood by those skilled in the art. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, and/or groups thereof.
In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.
In order that the invention may be readily understood, a further description of the invention will be rendered by reference to specific embodiments that are illustrated in the appended drawings and are not to be construed as limiting embodiments of the invention.
It will be appreciated by those skilled in the art that the drawings are merely schematic representations of examples and that the elements of the drawings are not necessarily required to practice the invention.
Example 1
The embodiment 1 of the invention provides a FPLG steady operation control method based on a vibration speed signal, which is characterized in that real-time combustion state information in an engine cylinder is obtained by analyzing the vibration speed signal of the surface of an engine body, and a circulation target generating capacity is determined based on the in-cylinder combustion state information, so that actual power generation is adjusted according to the target generating capacity, a rotor can be operated to be near an ideal position, and the stable operation of the FPLG is ensured.
In this embodiment, a back-mounted FPLG is described. The existing back-mounted type generator is characterized in that engine structures are arranged at two ends of a generator mandrel, a linear motor is arranged in the middle of the generator mandrel, and the linear motor has two functions of a motor and a generator. The rotor component comprises a piston, a connecting rod, a motor rotor and the like.
In the starting process, the motor serves as a motor to drag the piston to the designated top dead center position, whether the movement frequency of the rotor reaches the starting requirement is judged, and if the movement frequency reaches the starting requirement, the engine ignites and burns, and the motor serves as a generator to output electric energy.
And under the stable operation condition, the engine combusts to generate energy, a part of the energy generated by combustion is used for overcoming friction, a part of the energy is used for generating electricity, and a part of the energy is converted into kinetic energy of the rotor. If the operating frequency is stable, the kinetic energy of the rotor reaching the designated position against friction per cycle is stable, but the energy generated by combustion per cycle is unstable, so that the FPLG is ensured to run stably, and the generated energy needs to be adjusted according to the real-time in-cylinder combustion condition.
Analysis shows that when the operating frequency is stable, there is an approximately linear relationship between in-cylinder combustion mean indicated pressure (IMEP) and stroke power generation, as shown in fig. 2. Therefore, the IMEP can be used for judging and adjusting the power generation amount.
The mechanical principle and the mechanical vibration principle can show that in-cylinder combustion gas force directly acts on the rotor and the cylinder cover, and the vibration signal on the surface of the cylinder cover can directly reflect the excitation change. The surface vibration signals are classified into vibration displacement, velocity and acceleration signals. The surface vibration displacement signal is a low-frequency signal, the combustion information can be submerged, the speed can reflect medium-low frequency information, and the acceleration can mainly reflect high-frequency information, wherein some high-frequency information can contain more interference information. The vibration velocity signal is selected to reflect the in-cylinder combustion process.
In an ideal situation without other disturbances (no other excitation and system stiffness reaching a certain threshold), the engine surface vibration displacement can reflect the change of in-cylinder pressure before the in-cylinder pressure peak. The vibration velocity can accurately reflect combustion state information such as a combustion start point and peak pressure according to a differential relation between the vibration velocity and the vibration displacement. Theoretically, the vibration velocity can also effectively reflect the in-cylinder IMEP.
According to the engine principle, the average indicated pressure can be expressed as follows:
wherein ,Vh Representing the total volume of the cylinder, p i 、p i-1 The in-cylinder pressures at the times i, i-1 are shown, V i 、V i-1 The cylinder volume at the time i, i-1 is shown.
Based on the theoretical basis that the vibration displacement can describe the in-cylinder pressure linearly under ideal conditions, the vibration displacement S is adopted i Substituted middle P i The parameter of the mean effective displacement can be extracted by referring to the IMEP expression, as follows:
in the formula Smean The average effective displacement is herein simply referred to as the average displacement; s is S i 、S i-1 The cylinder vibration displacement at the moment of i and i-1 are respectively shown. S is S mean IMEP can be described linearly.
And combining the differential relation of the vibration displacement and the vibration speed to obtain an average displacement expression describing the extraction of the vibration speed of the IMEP, wherein the average displacement expression is as follows:
wherein ,S1 Representing the vibration displacement of the first point, v j The vibration speed of the j point is represented, delta t is sampling interval time, and n is the sampling point number of the selected vibration period.
The results show that the average displacement S extracted based on the vibration velocity of formula (3) mean There is an approximately linear relationship between IMEP obtained from in-cylinder pressure. As shown in fig. 4.
Therefore, S, which can be recognized by using the vibration speed mean And the linear relation between IMEP and the generated energy, the generated energy required by the stroke is calculated, the value is fed back to the control system, and the control system controls the output current to meet the power generation requirement by controlling the generator terminal voltage, so that the purpose of stable operation is realized.
Example 2
In the embodiment of the invention, how to realize stable operation is described by a back-mounted FPLG, and the whole control process is shown in fig. 5.
The back-mounted FPLG structure is shown in fig. 1, the middle part is provided with a linear motor 2, the linear motor 2 converts a generator and a motor, two sides of the linear motor 2 are respectively connected with a left cylinder 1 and a right cylinder 3 through a connecting flange 4 and bolts, and a piston 10, a connecting rod 11 and a rotor 12 of the linear motor 2 form a rotor assembly 7. The whole device is fixed on a test stand 6 through a bracket 5.
The back-mounted structure is symmetrically arranged for the two-stroke engine, and the position sensor 8 is arranged at different positions, and can also be directly arranged with the magnetic grid sensor so as to detect the position reached by the rotor component. Piezoelectric vibration velocity sensors 9 are mounted on the cylinder head surfaces of the left cylinder and the right cylinder to measure the vibration velocity of the cylinder head surfaces.
The specific control procedure of the control method in this embodiment is as follows:
when the motor is started, the driving force required by the motor is determined according to the mass of the rotor, and the piston is dragged to move to a designated ignition position (determined by a rotor displacement signal) and reaches the starting frequency; and if the starting condition is met, the controller controls the engine to ignite and burn.
Starting a starting process, wherein the mover is generally near the middle of the stroke under the action of force, the position of the mover in the middle of the stroke is set as a reference position, S=0 can be set, when the mover moves leftwards, the displacement is negative, and when the mover moves rightwards, the displacement is positive;
in order to ensure that the engine is smoothly started, the mover moves leftwards or rightwards under the action of the dragging force of the linear motor, and when the movement frequency of the mover and the top dead center position reached by the mover reach the engine starting condition, the engine can be ignited and burnt, and the starting condition is determined according to the engine requirements selected or designed by the FPGL;
calculating the dragging force required by the mover to move to the target position, and setting the dragging force F required by the mover to move from the middle of the stroke to the target position when the mover is firstly dragged leftwards 1 The method comprises the following steps:
in the formula ,PPress left =f (S) is the left cylinder gas compression pressure, which is a function of the piston displacement S, and can be calculated according to an empirical formula; a represents the stress area of the piston and is constant; s is S Target object Representing the displacement of the position of the mover moving object; f (F) f1 Is the friction force when moving leftwards from the middle of the stroke.
And recording motion information in a first dragging half stroke (1/4 of one cycle) according to the position sensor, judging whether the mover can reach the target displacement, and if not, dragging the next stroke. If the target displacement is reached, the time T used in the process is recorded 1 Calculating the motion frequency of the stroke rotor,and compared with the starting frequency, if the starting frequency is not met, the dragging of the next stroke is continued. If so, the control system controls the fuel injection ignition combustion of the engine. The start-up is completed.
When the target displacement and the target frequency cannot meet the starting conditions, calculating the required dragging force F from the left dead center to the right target position 2 。
in the formula ,PRight pressing The compression pressure of the gas in the cylinder at the right side is also a function of the piston displacement S and can be calculated according to an empirical formula; f (F) f2 Is the friction force when moving from the left dead center to the right.
Drag force F 2 The magnitude of the electromagnetic force is fed back to the control system and controls the motor to provide a rightward target electromagnetic force F 2 Recording position information in the process and time T from the left dead point to the right dead point 2 If the right dead point position reached by the process rotor is S 2 When S 2 If the target displacement is not satisfied, a third drag (from right dead center to left target position) is performed, if S 2 Satisfying the target displacement, calculating the frequency of the strokeComparison f 2 If the starting frequency is satisfied, if not, the third dragging is carried out, and if so, the system is controlled to spray oil, ignite and burn. The start-up is completed.
When the second dragging still cannot meet the starting condition, the third dragging is performed, the rotor is dragged to the left target position from the right dead center, and the dragging force is required to be as follows:
F f3 is the friction force when moving from the left dead center to the right. When the rotor moves to the designated position and the rotor movement frequency meets the starting frequency requirement, the controller controls the engine to ignite and burn to complete the starting process. When the rotor cannot meet the starting condition, the motor continues to provide the dragging force in the left direction and the right direction shown in the formulas (5) and (6), and the process is repeated until the starting condition is met, and the engine ignites and burns to complete the starting process.
After the FPLG system is started, the engine on one side is ignited to burn, when the burning energy is large enough, the energy can push the rotor to move to the top dead center position on the other side against friction, and meanwhile, a part of energy can be used for generating electricity.
Because of the combustion cycle variation, even under the same operation condition, obvious differences exist in different cycle combustion, namely, the combustion energy generated by each cycle is different, the system condition stability is ensured, the moving frequency of the mover can be regarded as a constant, therefore, the friction force of each cycle, the heat dissipation of the system and the kinetic energy which the mover should have can be regarded as constants, and the power generation amount needs to be adjusted to coordinate the influence of the combustion cycle variation if the mover can reach the vicinity of the designed top dead center position.
Once combustion is complete, the energy produced by the combustion is constant and there is a target value for the power generation of the stroke. Analysis shows that under the condition of ensuring stable operation, the same FPLG approximately has a linear relation between the stroke target power generation amount and the average indicated pressure IMEP of in-cylinder combustion, the relation can be obtained based on simulation or experiment, and the relation is shown in FIG. 3 as a IMEP and power generation amount relation curve obtained by researching a certain FPLG, and the relation can be stored in a control system.
The vibration response signals caused by IMEP and combustion excitation are closely related, and the combustion excitation directly acts on the cylinder cover, so that the vibration signals on the surface of the cylinder cover of the engine can directly reflect the in-cylinder combustion process.
Since the vibration response signal caused by combustion excitation may be disturbed by other excitation sources, the vibration response signal of the combustion period before the peak pressure after the start of combustion is selected as the analysis basis. Selection of vibration period As shown in FIG. 4, selection of the ab-segment vibration signal calculates IMEP, with point a representing the location of the start of combustion and point b representing the location of peak pressure.
Judging the position of the point a: and when the control system judges that the rotor moves to the position of the combustion starting point and ignites, the control system generates a trigger signal and starts to collect vibration speed signals corresponding to the cylinder cover surface of the combustion cylinder.
b, judging the position of the point b: due to combustion excitation, the vibration velocity signal undergoes a process in which the absolute value of the amplitude increases first, then decreases to zero, and then increases in reverse after combustion starts. Analysis shows that the vibration speed signal is at the first zero crossing point of the combustion period, namely the position corresponding to the peak pressure, namely the position of the point b. The control system can judge the change of the vibration speed from positive to negative or from negative to positive by comparing the magnitude and the positive and negative of the front and the rear points of the vibration speed, and can calculate the first zero crossing point position of the vibration speed through interpolation. After position b is determined, the system no longer collects vibration velocity signals.
S mean Is calculated by (1): calculating the average displacement S of vibration speed recognition according to formula (7) from the start of acquisition of vibration signal to the end of acquisition mean . And feeds this value back to the control system.
S mean And IMEP are in linear relation, and the MAP of the relation between the IMEP and the IMEP can be obtained based on experimental or simulation results and the results are stored in a control system.
S according to system feedback mean Value, and S mean And IMEP offAnd (3) calculating the relation between IMEP and the generated energy, and calculating the target generated energy W to be output by the system after the combustion is finished.
And according to the target power generation amount W, the control system controls the power generator to timely adjust the actual power generation amount output to approach the target power generation amount so as to ensure the movement of the rotor and realize the stable operation of the FPLG.
It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The foregoing description of the preferred embodiments of the present disclosure is provided only and not intended to limit the disclosure so that various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.
While the foregoing embodiments of the present disclosure have been described in conjunction with the accompanying drawings, it is not intended to limit the scope of the disclosure, and it should be understood that, based on the technical solutions disclosed in the present disclosure, various modifications or variations may be made by those skilled in the art without requiring any inventive effort, and are intended to be included in the scope of the present disclosure.
Claims (5)
1. The FPLG steady operation control method based on the vibration speed signal is characterized by comprising the following steps of:
step S110: the rotor moves under the action of the dragging force of the linear motor, and when the movement frequency of the rotor and the top dead center position which can be reached by the rotor reach the engine starting condition, the engine is started in an ignition way;
step S120: collecting vibration speed signals of the surface of the cylinder cover after starting in real time, and calculating and describing average displacement of average indicated pressure in the cylinder;
step S130: calculating an average indicated pressure from the average displacement;
step S140: calculating a stroke target power generation amount according to the average indicated pressure;
step S150: controlling the voltage of the generator terminal according to the target generating capacity, and further controlling the actual generating capacity to realize stable operation of the FPLG;
because vibration speed signals caused by combustion excitation can be interfered by other excitation sources, the vibration speed signals of the combustion period before the peak pressure after the combustion start point are selected as analysis basis, ab-section vibration signals are selected to calculate IMEP, a point represents the position of the combustion start point, and b point represents the position of the peak pressure;
judging the position of the point a: the method comprises the steps that a rotor movement displacement signal is used as a feedback signal, when a control system judges that a rotor moves to a combustion starting point position and ignites, the control system generates a trigger signal and starts to collect a vibration speed signal corresponding to the cylinder cover surface of a combustion cylinder;
b, judging the position of the point b: due to the effect of combustion excitation, the vibration speed signal can undergo the process that the absolute value of the amplitude is firstly increased and then reduced to zero after combustion starts, and then the amplitude is reversely increased, and analysis shows that the first zero crossing point of the vibration speed signal in the combustion period is the position corresponding to the peak pressure, namely the position of the point b, and the control system can judge the change of the vibration speed from positive to negative or from negative to positive by comparing the magnitude and the positive and negative of the front and rear points of the vibration speed and can calculate the first zero crossing point of the vibration speed through interpolation; after the position b is determined, the system does not collect vibration speed signals any more;
the average displacement of vibration speed recognition is calculated according to the following formula from the beginning of vibration signal collection to the end of vibration signal collectionAnd feeding back the value to the control system;
wherein ,representing the vibration displacement of the first point +.>Indicate->Vibration speed of point, +.>For sampling interval time, +.>Sampling points for the selected vibration period;
identified by vibration velocityAnd linear relation of IMEP and generating capacity, calculate the generating capacity that this stroke needs, feed back this value to the control system, the control system is through controlling the end voltage of the generator, and then control the output current to meet the power generation requirement, achieve the purpose of steady operation;
the step S110 specifically includes:
calculating the dragging force required by the mover to move to the target position, and setting the dragging force required by the mover to move from the middle of the stroke to the target position when the mover is dragged leftwardsThe method comprises the following steps:
in the formula ,the left cylinder gas compression pressure is about the piston displacement +.>Can be calculated according to an empirical formula; />The stressed area of the piston is represented as a constant; />Representing the displacement of the position of the mover moving object; />Is the friction force when moving leftwards from the middle of the stroke;
recording motion information in a first dragging half stroke according to the position sensor, judging whether the mover can reach target displacement, and if not, dragging the next stroke; if the target displacement is reached, the time taken by the process is recordedCalculating the stroke mover movement frequency, < >>Comparing with the starting frequency, and if the starting frequency is not met, continuing dragging of the next stroke; if the fuel injection ignition and combustion of the engine are satisfied, the control system controls the fuel injection and ignition and combustion of the engine; starting is completed;
when the target displacement and the target frequency cannot meet the starting conditions, calculating the required dragging force from the left dead center to the right target position；
in the formula ,is the right cylinder gas compression pressure, also a function of piston displacement S; />Is the friction force when moving from the left dead center to the right;
will drag the forceThe magnitude is fed back to the control system and the motor is controlled to provide a rightward target electromagnetic force +.>Recording the position information in the process and the time from left dead point to right dead point +.>If the right dead center position reached by the process mover is + ->When->When the target displacement is not satisfied, the third dragging is performed, namely, from the right dead point to the left target position, if +>Satisfying the target displacement, calculating the frequency of the stroke +.>Comparison->If the starting frequency is met, if not, the third dragging is carried out, and if so, the system is controlled to spray oil, ignite and burn; starting is completed;
when the second dragging still cannot meet the starting condition, the third dragging is performed, the rotor is dragged to the left target position from the right dead center, and the dragging force is required to be as follows:
is the slaveWhen the rotor moves to a designated position and the moving frequency of the rotor meets the requirement of starting frequency, the controller controls the ignition combustion of the engine to finish the starting process; when the rotor cannot meet the starting condition, the motor continues to provideF 2 AndF 3 the dragging forces in the left direction and the right direction shown in the formula are repeated in this way until the starting condition is met, and the engine ignites and burns to complete the starting process.
2. An FPLG steady operation control system based on a vibration velocity signal, characterized by comprising:
the starting module is used for dragging the rotor to move under the action of the dragging force of the linear motor, and controlling the engine to start when the movement frequency of the rotor and the top dead center position which can be reached by the rotor reach the engine starting condition;
the first calculation module is used for collecting vibration speed signals of the active cell after starting in real time and calculating and describing average displacement of average indicated pressure in the cylinder;
the second calculation module is used for calculating average indicated pressure according to the average displacement;
the third calculation module is used for calculating the generated energy required by the stroke by utilizing the linear relation between the average indicated pressure and the generated energy;
the control module is used for controlling the voltage of the generator terminal according to the target generated energy, further controlling the actual generated energy and realizing the stable operation of the FPLG;
because vibration speed signals caused by combustion excitation can be interfered by other excitation sources, the vibration speed signals of the combustion period before the peak pressure after the combustion start point are selected as analysis basis, ab-section vibration signals are selected to calculate IMEP, a point represents the position of the combustion start point, and b point represents the position of the peak pressure;
judging the position of the point a: the method comprises the steps that a rotor movement displacement signal is used as a feedback signal, when a control system judges that a rotor moves to a combustion starting point position and ignites, the control system generates a trigger signal and starts to collect a vibration speed signal corresponding to the cylinder cover surface of a combustion cylinder;
b, judging the position of the point b: due to the effect of combustion excitation, the vibration speed signal can undergo the process that the absolute value of the amplitude is firstly increased and then reduced to zero after combustion starts, and then the amplitude is reversely increased, and analysis shows that the first zero crossing point of the vibration speed signal in the combustion period is the position corresponding to the peak pressure, namely the position of the point b, and the control system can judge the change of the vibration speed from positive to negative or from negative to positive by comparing the magnitude and the positive and negative of the front and rear points of the vibration speed and can calculate the first zero crossing point of the vibration speed through interpolation; after the position b is determined, the system does not collect vibration speed signals any more;
the average displacement of vibration speed recognition is calculated according to the following formula from the beginning of vibration signal collection to the end of vibration signal collectionAnd feeding back the value to the control system;
wherein ,representing the vibration displacement of the first point +.>Indicate->Vibration speed of point, +.>For sampling interval time, +.>Sampling points for the selected vibration period;
identified by vibration velocityAnd linear relation of IMEP and generating capacity, calculate the generating capacity that this stroke needs, feed back this value to the control system, the control system is through controlling the end voltage of the generator, and then control the output current to meet the power generation requirement, achieve the purpose of steady operation;
the starting module is also used for:
calculating the dragging force required by the mover to move to the target position, and setting the dragging force required by the mover to move from the middle of the stroke to the target position when the mover is dragged leftwardsThe method comprises the following steps:
in the formula ,the left cylinder gas compression pressure is about the piston displacement +.>Can be calculated according to an empirical formula; />The stressed area of the piston is represented as a constant; />Representing the displacement of the position of the mover moving object; />Is the friction force when moving leftwards from the middle of the stroke;
recording motion information in a first dragging half stroke according to the position sensor, judging whether the mover can reach target displacement, and if not, dragging the next stroke; if the target displacement is reached,the time taken for the process is recordedCalculating the stroke mover movement frequency, < >>Comparing with the starting frequency, and if the starting frequency is not met, continuing dragging of the next stroke; if the fuel injection ignition and combustion of the engine are satisfied, the control system controls the fuel injection and ignition and combustion of the engine; starting is completed;
when the target displacement and the target frequency cannot meet the starting conditions, calculating the required dragging force from the left dead center to the right target position；
in the formula ,is the right cylinder gas compression pressure, also a function of piston displacement S; />Is the friction force when moving from the left dead center to the right;
will drag the forceThe magnitude is fed back to the control system and the motor is controlled to provide a rightward target electromagnetic force +.>Recording the position information in the process and the time from left dead point to right dead point +.>If the process is enabled by the moverThe right dead center position reached is +.>When->When the target displacement is not satisfied, the third dragging is performed, namely, from the right dead point to the left target position, if +>Satisfying the target displacement, calculating the frequency of the stroke +.>Comparison->If the starting frequency is met, if not, the third dragging is carried out, and if so, the system is controlled to spray oil, ignite and burn; starting is completed;
when the second dragging still cannot meet the starting condition, the third dragging is performed, the rotor is dragged to the left target position from the right dead center, and the dragging force is required to be as follows:
when the rotor moves to a designated position and the moving frequency of the rotor meets the starting frequency requirement, the controller controls the ignition combustion of the engine to finish the starting process; when the rotor cannot meet the starting condition, the motor continues to provideF 2 AndF 3 the dragging forces in the left direction and the right direction shown in the formula are repeated in this way until the starting condition is met, and the engine ignites and burns to complete the starting process.
3. A non-transitory computer readable storage medium characterized by: the non-transitory computer readable storage medium comprising instructions for performing the method of claim 1.
4. An electronic device, characterized in that: a non-transitory computer readable storage medium comprising the method of claim 3; and one or more processors capable of executing the instructions of the non-transitory computer-readable storage medium.
5. An electronic device, characterized in that: the apparatus comprising means for performing the method of claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011138476.3A CN112228233B (en) | 2020-10-22 | 2020-10-22 | FPLG stable operation control method and system based on vibration speed signal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011138476.3A CN112228233B (en) | 2020-10-22 | 2020-10-22 | FPLG stable operation control method and system based on vibration speed signal |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112228233A CN112228233A (en) | 2021-01-15 |
| CN112228233B true CN112228233B (en) | 2023-10-03 |
Family
ID=74110266
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011138476.3A Active CN112228233B (en) | 2020-10-22 | 2020-10-22 | FPLG stable operation control method and system based on vibration speed signal |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112228233B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112818520B (en) * | 2021-01-18 | 2022-08-23 | 山东休普动力科技股份有限公司 | Vibration signal-based FPLG control strategy simulation model construction method and system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009015596A1 (en) * | 2007-07-29 | 2009-02-05 | Minglong Tang | A forced vibration directly driving generation system with an accelerating spring |
| CN109736957A (en) * | 2018-12-20 | 2019-05-10 | 南京理工大学 | A kind of free-piston engine start-up course control method |
| CN110608104A (en) * | 2019-09-20 | 2019-12-24 | 山东休普动力科技股份有限公司 | Control method for stabilizing top dead center position of free piston linear generator |
| WO2020128515A2 (en) * | 2018-12-21 | 2020-06-25 | Libertine Fpe Ltd | Method and system for controlling a free piston mover |
-
2020
- 2020-10-22 CN CN202011138476.3A patent/CN112228233B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009015596A1 (en) * | 2007-07-29 | 2009-02-05 | Minglong Tang | A forced vibration directly driving generation system with an accelerating spring |
| CN109736957A (en) * | 2018-12-20 | 2019-05-10 | 南京理工大学 | A kind of free-piston engine start-up course control method |
| WO2020128515A2 (en) * | 2018-12-21 | 2020-06-25 | Libertine Fpe Ltd | Method and system for controlling a free piston mover |
| CN110608104A (en) * | 2019-09-20 | 2019-12-24 | 山东休普动力科技股份有限公司 | Control method for stabilizing top dead center position of free piston linear generator |
Non-Patent Citations (5)
| Title |
|---|
| 唐娟.基于振动信号评价柴油机缸内燃烧状态的研究.《基于振动信号评价柴油机缸内燃烧状态的研究》.2011,摘要第11页、正文第33页、55页. * |
| 唐娟等.基于振动速度的柴油机缸内峰值压力提取方法研究.《基于振动速度的柴油机缸内峰值压力提取方法研究》.2019,第89-90页. * |
| 基于振动信号评价柴油机缸内燃烧状态的研究;唐娟;《基于振动信号评价柴油机缸内燃烧状态的研究》;20110731;摘要第11页、正文第33、55页 * |
| 基于振动速度的柴油机缸内峰值压力提取方法研究;唐娟等;《基于振动速度的柴油机缸内峰值压力提取方法研究》;20190830;第89-90页 * |
| 直线发动/发电机启动性能仿真研究;邓俊等;《同济大学学报（自然科学版）》;20130430;第596-599页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112228233A (en) | 2021-01-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Feng et al. | Research on the intermediate process of a free-piston linear generator from cold start-up to stable operation: Numerical model and experimental results | |
| CN110529268B (en) | Method for stable operation of composite free piston linear generator | |
| CN112267939B (en) | FPLG stable operation control method and system based on vibration acceleration signal | |
| CN112228233B (en) | FPLG stable operation control method and system based on vibration speed signal | |
| Wu et al. | Semi-analytical modelling of a hydraulic free-piston engine | |
| CN109653869B (en) | Two-stroke free piston power generation system and power generation method thereof | |
| Gonca et al. | Performance analysis and simulation of a diesel-miller cycle (DiMC) engine | |
| Lin et al. | Thermodynamic simulation and prototype testing of a four-stroke free-piston engine | |
| CN110608104B (en) | Control method for stabilizing top dead center position of free piston linear generator | |
| JP2008223628A (en) | Control device for free piston engine | |
| Lu et al. | Compression ratio control of an opposed-piston free-piston engine generator based on artificial neural networks | |
| Vu et al. | Piston motion control for a dual free piston linear generator: predictive-fuzzy logic control approach | |
| Lu et al. | A starting control strategy of single-cylinder two-stroke free-piston engine generator | |
| CN106194448B (en) | The control device of internal combustion engine | |
| JP2011202621A (en) | Control device of internal combustion engine | |
| CN109488471B (en) | Method for controlling stable operation process of free piston engine | |
| Schneider et al. | Experimental investigation and analysis of homogeneous charge compression ignition in a two-stroke free-piston engine | |
| Dönitz et al. | Validation of the fuel saving potential of downsized and supercharged hybrid pneumatic engines using vehicle emulation experiments | |
| Hu et al. | Fuel combustion under asymmetric piston motion: Tested results | |
| Chen et al. | A novel stable control strategy of single cylinder free-piston linear generator | |
| CN112761782B (en) | Free piston linear generator motion characteristic simulation analysis method and system | |
| CN112324563B (en) | Double-winding free piston linear generator and control method | |
| CN112836290B (en) | Free piston linear motor matching optimization method based on system output | |
| Sun et al. | Investigation of control method for starting of linear internal combustion engine-linear generator integrated system | |
| CN112818520B (en) | Vibration signal-based FPLG control strategy simulation model construction method and system |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |