CN105157914A - System and method for conversion from time domain to angle domain of internal combustion engine internal cylinder pressure signal - Google Patents

Abstract

The invention discloses a system and method for conversion from a time domain to an angle domain of an internal combustion engine internal cylinder pressure signal. The system comprises a cylinder pressure measurement device and a pulse signal measurement device. The cylinder pressure measurement device and the pulse signal measurement device transmit a collected internal cylinder pressure signal and a pulse signal corresponding to a flywheel ring gear to an internal clock collection system; the internal clock collection system transmits the received data to a processor for processing; and a precise zero crossing point of the pulse signal is determined based on an interpolation algorithm and conversion from a time domain to an angle domain of the internal cylinder pressure signal is realized. Therefore, a problem of mistaken triggering caused by coder signal loss or interference according to the traditional testing method can be solved effectively; and thus reliability of the data acquisition process can be effectively improved.

Description

A kind of system and method for internal combustion engine cylinder pressure signal time domain gyration territory

Technical field

The present invention relates to the method for testing of internal combustion engine cylinder pressure signal, be specifically related to a kind of system and method for the internal combustion engine cylinder pressure signal time domain gyration territory based on interpolation algorithm.

Background technology

Internal combustion engine cylinder pressure signal has contained the abundant information of in-cylinder combustion process, and these information can be improved for the research and development of internal combustion engine and performance and provide important reference frame.Every 720 crank angle degrees of internal combustion engine are a working cycle, are all that benchmark launches when gathering cylinder pressure signal and analyze with crank angle.For this reason, existing cylinder pressure signal test macro many employings external clock sample mode test in-cylinder pressure.This method of testing needs to adopt scrambler to provide trigger pip, carries out data acquisition for controlling test macro by specific angle step.Need the housing of scrambler to be connected on the body of engine in use procedure, the rotating shaft of scrambler is connected to the bent axle of engine.After scrambler is fixing, bent axle drives scrambler rotating shaft to rotate when the engine operates, and scrambler converts the amount of spin of bent axle to pulse signal by photoelectricity transformation principle, for triggering collection system acquisition cylinder pressure signal.

This method needs to find correct position regular coding device at the free end of engine, and because current engine free end pieces is many, integrated level is high, the fixing difficulty of scrambler is large.Scrambler rotating shaft and crankshaft-synchronous rotate, and the concentricity of both requirements is high, if there is deviation at both centers, easily cause encoder output to lose, even the problem such as scrambler rotating shaft fracture, produce adverse influence to the reliably working of whole test macro.In addition, scrambler exports as high-frequency pulse signal, and after this signal is sent into and carried out Shape correction in test macro, for triggering sampling, engine test scene exists the multiple interference such as dynamometer, easily causes test macro sampling by mistake.

According to the above-mentioned analysis to having cylinder pressure signal method of testing at present, there is sensor and install inconvenience in existing method, is subject to the problems such as disturbing effect; And due to scrambler installation difficulty, current the method can only be applicable to the occasion of laboratory test, for vehicular engine, because engine free end spaces limit, is difficult to the test realizing in-cylinder pressure.

Summary of the invention

For solving the deficiency that prior art exists, the invention discloses one and utilizing internal clock acquisition system to test cylinder pressure signal, and then by interpolation algorithm, the time-domain signal of collection being converted to the method for angle domain signal.The method no longer adopts scrambler to trigger sampling, but installs pulsed test signal sensor at engine flywheel end, gathers cylinder pressure signal and pulse signal by internal clock acquisition system simultaneously.Be that benchmark carries out interpolation processing to cylinder pressure signal with pulse signal after collection, realize the conversion of time-domain signal and angle domain signal.The Pluse signal sensor that the method adopts only needs to be arranged near flywheel ring gear, and installation requirement is low, easily realizes; Adopt internal clock sample mode collection signal, eliminate external clock sample mode and to be easily interfered the sampling abnormal problem that signal false triggering causes.

For achieving the above object, concrete scheme of the present invention is as follows:

A kind of system of internal combustion engine cylinder pressure signal time domain gyration territory, comprise: cylinder pressure measuring device and pulse measure device, the cylinder pressure signal of collection and pulse signal corresponding to flywheel ring gear are sent to internal clock acquisition system by described cylinder pressure measuring device and pulse measure device, and the data of reception are sent to processor and process by described internal clock acquisition system further;

Within a processor, obtain by interpolation algorithm point and the zero crossing that pulse measure device output voltage is zero, obtain the time interval of adjacent two between cog according to the data of zero crossing, obtain the data of two arbitrarily angled correspondences of between cog further by interpolation algorithm.

Further, described cylinder pressure measuring device comprises cylinder pressure sensor, and described cylinder pressure sensor is arranged on engine cylinder and covers, and is connected to the firing chamber of engine by measuring pressure passage.

Further, described pulse measure device is arranged on engine flywheel end, and the tooth top of pulse measure device front end distance flywheel ring gear is about 1mm, during engine operation, each tooth of flywheel ring gear, through this sensor, all can produce a pulse signal by trigger sensor.

Further, described pulse measure device adopts magnetoelectric sensor.

Further, described internal clock acquisition system be within the multi-channel high-speed data capture card of clock sampling mode work, the data transfer mode of multi-channel high-speed data capture card adopts USB interface or pci interface high speed data transmission interface and processor communication.

The method in internal combustion engine cylinder pressure signal time domain gyration territory, comprising:

The output voltage being obtained pulse measure device by interpolation algorithm is the point of zero and moment Tstart and Tend of zero crossing; The signal of footmark signal and pulse measure device to test;

Moment Tstart and Tend is duration corresponding to engine flywheel gear ring tooth between these two moment, angle corresponding between two moment of moment Tstart and Tend is the angular duration θ of a tooth;

According to the angular duration θ of two moment of Tstart and Tend, a tooth and cylinder pressure signal is converted into the angle intervals θ after angle domain by time domain _{interpolation interval}determine the time step T between angle domain cylinder pressure signal consecutive point _step;

According to sampling interval T _step, as nipper initial time Tstart and first the angle domain point obtained when nipper interpolate value and the angular deviation T when between nipper initial time Tstart _offobtain being converted into moment T corresponding to angle domain _n, n=0,1,2,3

According to the corresponding moment T of the angle domain obtained _n, n=0,1,2,3 ..., then each point in-cylinder pressure numerical value y of angle domain is converted into _n, n=0,1,2,3 ... obtained by the time domain cylinder pressure signal linear interpolation of surveying before and after this point.

Further, when the output voltage obtaining pulse measure device is point and the zero crossing of zero, adopt 3 Newton interpolation methods by interpolation algorithm, first obtain each two points before and after zero crossing, (x ₀, y ₀), (x ₁, y ₁), (x ₂, y ₂) and (x ₃, y ₃), wherein, x ₀~ x ₃for the sampling sequence number of each sampled point, because four points are continuous print sampled point, the interval of adjacent spots all differs 1 sampled point moment; And y ₀~ y ₃then refer to the pulse signal sampling result of before and after zero crossing 2, x, y all in Newton interpolation formula are put upside down use, make y equal zero, obtain corresponding x value.

Further, the number of teeth of angle θ: θ=360 ° of corresponding between two moment of moment Tstart and Tend CA/ flywheel ring gears.

Further, interval time, difference was T _step:

In formula, θ is the angle that flywheel ring gear tooth continues; θ _{interpolation interval}for the angle intervals being converted into adjacent 2 of angle domain of setting; T _startand T _endfor the zero crossing time data obtained by interpolation.

Further, the moment T that each moment of angle domain is corresponding _nthe expression formula of (n=0,1,2,3...) is:

T _n＝Tstart+n×T _step+T _off

In formula, T _offfor first the angle domain point obtained when nipper interpolate value and the angular deviation of working as between nipper initial time Tstart.

Beneficial effect of the present invention:

1) the present invention proposes one, near engine flywheel gear ring, Pluse signal sensor is installed, and for realizing the new method that cylinder pressure signal gathers.The installation requirement of Pluse signal sensor is low, easily realizes; Effectively solve in conventional cylinder pressure method of testing the difficulty adopting the scrambler existed during scrambler to fix difficulty and need to ensure that scrambler rotating shaft is concentric with bent axle height.

2) cylinder pressure signal and pulse signal are first gathered as simulating signal by internal clock acquisition method by the cylinder pressure signal method of testing that the present invention proposes, then by the accurate zero crossing of interpolation algorithm determination pulse signal, realize cylinder pressure signal on this basis by the conversion of time domain to angle domain; The method effectively prevent the problem occurring false triggering in conventional test methodologies because code device signal is lost or be interfered, and effectively raises the reliability of data acquisition.

Accompanying drawing explanation

Fig. 1 is hardware configuration schematic diagram of the present invention;

The cylinder pressure signal of 5 circulations that Fig. 2 (a) is actual measurement and pulse signal correlation curve;

Time domain cylinder pressure signal to be converted into the signature tune line chart of angle domain for the interpolation algorithm that proposed by the present invention by Fig. 2 (b);

Fig. 3 is the zero crossing moment schematic diagram of the Pluse signal sensor that sampling process of the present invention obtains;

Fig. 4 is cylinder pressure signal time domain gyration territory of the present invention principle.

Embodiment:

Below in conjunction with accompanying drawing, the present invention is described in detail:

The present invention installs inconvenience, code device signal loss in view of the scrambler that current cylinder pressure signal method of testing exists or is disturbed the problems such as impact easily causes sampling abnormal, the present invention proposes the new method of a kind of cylinder pressure signal test.The advantages such as it is easy for installation that this method has sensor, reliable operation, can meet the needs of internal combustion engine research and development and production unit cylinder pressure signal test analysis, have broad application prospects.

The present invention proposes a kind of method of testing and the system that are applicable to cylinder pressure signal collection, comprise hardware system and method for testing and analyzing two parts.

1. hardware system introduction: hardware system comprises sensor and internal clock data acquisition system (DAS) two parts, wherein sensor comprises the pressure transducer for testing cylinder pressure signal and is arranged on the pulsed test signal sensor near flywheel ring gear.Wherein cylinder pressure sensor is arranged on engine cylinder and covers, and is connected to the firing chamber of engine by measuring pressure passage, and this sensor exports as simulating signal.Pluse signal sensor is just installed the tooth of flywheel ring gear, during engine operation, each tooth of flywheel ring gear is through this sensor, and all can produce a pulse signal by trigger sensor, this signal is pressed by cylinder signal to be converted to the time reference of angle domain from time domain.

The basis of put forward the methods of the present invention is the exact time being found zero crossing by interpolation algorithm, and this requires have some sampled points to exist before and after zero crossing.Pluse signal sensor conventional at present mainly comprises: magneto-electric, Hall-type and photo-electric, the signal that latter two sensor exports only has height two kinds of level, and counting before and after zero crossing is few, cannot meet request for utilization, therefore comparatively speaking, magnetoelectric sensor is the optimal selection of this method.

Internal clock acquisition system namely within the multi-channel high-speed data capture card of clock sampling mode work, this type of capture card utilizes the clock signal triggering AD conversion unit carried to realize data acquisition.Because this method requires that capture card has higher sample rate, therefore, the data transfer mode of capture card needs to adopt the high speed data transmission interface such as USB interface or pci interface.The signal of the cylinder pressure sensor that this method adopts and Pluse signal sensor is all sent in high-speed data acquisition card, and each signal is carried out data acquisition as analog quantity, and the data after collection are processed by following method.

2. method for testing and analyzing introduction: in order to the data transformations that internal clock is sampled be with crank angle be benchmark data need by following two steps: the zero crossing 1) being obtained Pluse signal sensor by interpolation algorithm; 2) take zero crossing as benchmark, adopt interpolation algorithm to change time domain cylinder pressure signal, obtaining take angle as the data of benchmark.Below each several part content is described:

1) acquisition of zero crossing

Zero crossing and Pluse signal sensor output voltage are the point of 0, and the time between pulse signal two adjacent zero crossings is duration of a tooth, and there is important effect this time for time domain cylinder pressure signal gyration territory.Due to gatherer process be separated in time collection once, therefore by means of only data acquisition, completely cannot obtain the data of each zero crossing of Pluse signal sensor.Utilize the value of sampled point before and after zero crossing at this, obtained the exact time of zero crossing by interpolation algorithm.Be illustrated in figure 3 the schematic diagram of the Pluse signal sensor that sampling process obtains, in figure, closed square represents the data of sampling, and the circular position representing zero crossing.

The present invention adopts the position of interpolation determination zero crossing, have employed the multiple interpolation algorithms such as Newton interpolation, Lagrange interpolation and Hermit interpolation, all have employed different order to often kind of method to contrast, find that the result that distinct methods obtains is close, at this with the defining method of 3 Newton interpolation method explanation zero crossings.3 Newton interpolation methods need to use each two points before and after zero crossing and calculate, and four points are as follows: (x ₀, y ₀), (x ₁, y ₁), (x ₂, y ₂) and (x ₃, y ₃), wherein, x ₀~ x ₃for the sampling sequence number of each sampled point, because four points are continuous print sampled point, the interval of adjacent spots all differs 1 sampled point moment; And y ₀~ y ₃then refer to the sampled result of before and after zero crossing 2, therefore, x ₀~ x ₃and y ₀~ y ₃be known quantity.

Newton interpolation formula is expressed as follows:

Y=N _n(x)=f [x ₀]+f [x ₀, x ₁] (x-x ₀)+interpolation

F [x ₀, x ₁, x ₂] (x-x0) (x-x1)+...+quadratic interpolation

f[x ₀,x ₁,...x _n](x-x ₀)(x-x ₁)...(x-x _n-1)

Rn (x)=f [x, x ₀..., x _n] π _n(x) remainder of interpolation

When determining zero crossing, be actually _ybe worth known, ask x, for the ease of use interpolation algorithm, for this reason by x all in formula, _yall put upside down use, obtain 3 Newton interpolation algorithms thus as follows:

x＝N _n(y)

＝f(y ₀)+f[y ₀，y ₁](y-y0)+f[y ₀，y ₁，y ₂](y-y ₀)(y-y ₁)+

f[y ₀，y ₁，y ₂，y ₃](y-y ₀)(y-y ₁)(y-y ₂)

Wherein, $\begin{array}{ccc}f\[y_0,y_1\]=\frac{x_0-x_1}{y_0-y_1}& f\[y_1,y_2\]=\frac{x_1-x_2}{y_1-y_2}& f\[y_2,y_3\]=\frac{x_2-x_3}{y_2-y_3}\end{array}$

$f\[y_0,y_1,y_2\]=\frac{f\[y_0,y_1\]-f\[y_1,y_2\]}{y_0-y_2}$

$f\[y_1,y_2,y_3\]=\frac{f\[y_1,y_2\]-f\[y_2,y_3\]}{y_1-y_3}$

$f\[y_0,y_1,y_2,y_3\]=\frac{f\[y_0,y_1,y_2\]-f\[y_1,y_2,y_3\]}{y_0-y_3};$

In addition, for zero crossing, its y=0, can obtain thus:

$x=f\left(y_0\right)+\frac{x_0-x_1}{y_0-y_1}(-y_0)+\frac{\frac{x_0-x_1}{y_0-y_1}-\frac{x_1-x_2}{y_1-y_2}}{y_0-y_2}(-y_0)(-y_1)+$

$\frac{\frac{\frac{x_0-x_1}{y_0-y_1}-\frac{x_1-x_2}{y_1-y_2}}{y_0-y_2}-\frac{\frac{x_1-x_2}{y_1-y_2}-\frac{x_2-x_3}{y_2-y_3}}{y_1-y_3}}{y_0-y_3}(-y_0)(-y_1)(-y_2)$

In above formula, x ₀=f (y ₀), and (x ₀, y ₀), (x ₁, y ₁) be front 2 points of zero crossing; (x ₂, y ₂), (x ₃, y ₃) be 2 points after zero crossing, four points are neighbouring sample point, therefore, x ₀-x ₁=x ₁-x ₂=x ₂-x ₃=-1, above formula can be written as:

$x=x_0+\frac{1}{y_0-y_1}\left(y_0\right)+\frac{\frac{1}{y_1-y_2}-\frac{1}{y_0-y_1}}{y_0-y_2}\left(y_0\right)\left(y_1\right)\frac{\frac{\frac{1}{y_1-y_2}-\frac{1}{y_0-y_1}}{y_0-y_2}-\frac{\frac{1}{y_2-y_3}-\frac{1}{y_1-y_2}}{y_1-y_3}}{y_0-y_3}\left(y_0\right)\left(y_1\right)\left(y_2\right)$

X in the variable related in above formula ₀for sampled point moment, y ₀~ y ₃for adjacent 4 pulse signal time-domain sampling point value, these parameters are known quantity, can obtain the data of each zero crossing according to above formula.After the data of zero crossing obtain, the precise time interval of adjacent two between cog can be obtained.

2) method in in-cylinder pressure time domain gyration territory

The precise moments of footmark signal zero crossing can be obtained by above-mentioned interpolation algorithm, namely Tstart and Tend shown in Fig. 4 is descended, the duration that engine flywheel gear ring tooth is corresponding is, the number of teeth of angle θ=360 ° CA/ flywheel ring gear corresponding between these two moment between these two moment.Suppose in this method that the rotating speed of engine in a tooth is identical, thus, the data of two arbitrarily angled correspondences of between cog can be obtained further by interpolation algorithm, as shown in Figure 4, for cylinder pressure signal time domain gyration territory schematic diagram, for this figure, implementation process is described.T in figure ₀, T ₁, T ₂and T ₃be difference for T _stepeach time data of time, T _stepexpression formula as follows:

In formula, θ is the angle of adjacent two between cog of flywheel ring gear; θ _{interpolation interval}for being converted into the angle intervals of angle domain; T _startand T _endfor the zero crossing data obtained by interpolation; Be converted into the moment T that each point of angle domain is corresponding _n(n=0,1,2,3 ...) expression formula be:

T _n＝Tstart+n×T _step+T _off

In formula, T _offfor first the angle domain point obtained when nipper interpolate value and the angular deviation of working as between nipper initial time Tstart, T for the calculating of the 1st tooth _offbe 0, for the 2nd tooth in figure, T _off=T ₃-Tend.

Once each moment T of in-cylinder pressure after obtaining being converted into angle domain _n(n=0,1,2,3 ...), then the numerical value y of in-cylinder pressure each point in angle domain _n(n=0,1,2,3 ...) by former and later two time domain cylinder pressure data (T gathered of this point _{before n}, y _{before n}) and (T _{after n}, y _{after n}) linear interpolation can obtain, wherein, T _{before n}and T _{after n}for the sampling instant of 2, front and back, both differences are 1, y _{before n}and y _{after n}for the in-cylinder pressure value of 2, front and back, with T ₁moment is example, and in-cylinder pressure value corresponding to this moment is y ₁expression formula as follows:

Adopt the method the time domain data of internal clock capture card collection can be converted into interpolation and be spaced apart θ _{interpolation interval}the angle domain data of ° CA.

Angle domain can be converted into by when the time domain pressure signal in nipper by said method, in each tooth, all adopt said method to carry out processing.

This method needs to utilize interpolation algorithm to obtain the moment of zero crossing, and needing before and after zero crossing counts accordingly can ensure that Interpolation Process is carried out smoothly, counts relevant with the rotating speed of the interpolation algorithm adopted, sample frequency and engine.In engine working process, rotation speed change haves a wide reach, and rotating speed is higher, the time of a circulation is shorter, and in order to ensure counting enough needed for interpolation, the sample frequency of needs is higher, only need ensure that sample frequency can obtain enough sampling numbers, at the slow-speed of revolution and no problem at high rotating speed.

Different interpolation algorithms needs the difference of counting before and after zero crossing, is still described with 3 Newton interpolation algorithms below.Known by above-mentioned analysis, when adopting 3 Newton interpolation methods calculated zero points, respectively need 2 sampled points to be used for calculating before and after zero crossing, therefore, in the duration of a tooth, at least should be able to gather the sampled point of more than 8, calculate with 8 points temporarily.Assuming that the number of teeth of engine flywheel gear ring is z, then the sampling number of one, engine circulation is 8 × 2 × z, and rotating speed is n ₁time one circulation time be second, the sample frequency that can obtain thus under current rotating speed is:

$\frac{8\×2\×z}{\frac{120}{n_1}}=\frac{8\×2\×z\×n_1}{120}$

Assuming that engine ring gear number is 141, the highest running speed is 2200r/min, then can obtain single pass sample frequency according to above formula can not lower than 41.36kHz.

When gathering cylinder pressure signal and analyze, to the requirement of having counted of sampling, the period of at every turn sampling as diesel engine General Requirements is more than 100; For gasoline engine, because Combustion Cycle Variability is comparatively large, therefore sample cyclic number is more than 150.Can determine sample frequency by said method, when engine speed is different, the corresponding time of often circulating is different, and the sampling number therefore required is not identical yet, and rotating speed is lower, and the time of a circulation is longer, and corresponding sampling number is more.The computing method of sampling number are analyzed, assuming that engine speed is n ₂, the period needing sampling is m, then the expression formula of corresponding sampling number is as follows:

$\frac{120}{n_2}\×m\×\frac{8\×2\×z\×n_1}{120}$

Assuming that engine ring gear number is for being 141, the highest running speed is 2200r/min, assuming that idling speed is 600r/min, now needs the data that collection 100 circulates, then the sampling number that now each sampling needs is: 827200 points.

The method that the present invention proposes is when practical application, sample frequency and sampling number is reasonably selected according to the flywheel number of teeth of engine, the range of speeds of operation, the cylinder pressure signal of internal clock collection can be converted into angle domain signal according to above-mentioned interpolation algorithm, for carrying out subsequent analysis.

The present invention is when applying, and accompanying drawing 1 proposes the hardware configuration schematic diagram of method of testing for the present invention, and this method needs to use cylinder pressure sensor and Pluse signal sensor, and each signal is all as the collection realizing data in simulating signal feeding internal clock data acquisition system (DAS).Because the data volume gathered is large, therefore analog-to-digital result is sent to computer by high speed data transmission interfaces such as USB or PCI, and carries out follow-up analysis.The clock that internal clock acquisition system carries with inside carries out data acquisition, and therefore the time interval of each sampled point of signal is fixed, and the signal of namely sampling take time as benchmark.Be a cycle period sex work with 720 crank angle degrees during internal combustion engine, needing in order to crank angle when combustion motor cylinder pressure signal is analyzed is that benchmark is analyzed, therefore need the signal of time domain to be converted to angle domain signal, and this process is the content that the present invention relates generally to.

Actual measurement engine cylinder pressure signal is converted to the correlation curve after angle domain by time domain for utilizing this method by accompanying drawing 2.Wherein Fig. 2 (a) is cylinder pressure signal and the pulse signal correlation curve of 5 circulations of actual measurement, and wherein horizontal ordinate is sampling number, and because the sample frequency of internal clock sampling is fixed, therefore sampling number and time are mutually corresponding.As can be seen from the figure sample frequency is high, and cylinder pressure signal and pulse signal sampling are counted all more.Time domain cylinder pressure signal to be converted into the signal of angle domain, angle intervals θ during conversion for the interpolation algorithm that proposed by the present invention by Fig. 2 (b) _{interpolation interval}be set as 0.5 DEG C of A, namely each circulation has 1440 points.Can be found out by the contrast of two figure, the signal of internal clock collection can be converted into angle domain by method that the present invention proposes accurately.

By reference to the accompanying drawings the specific embodiment of the present invention is described although above-mentioned; but not limiting the scope of the invention; one of ordinary skill in the art should be understood that; on the basis of technical scheme of the present invention, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection scope of the present invention.

Claims (10)

1. the system in an internal combustion engine cylinder pressure signal time domain gyration territory, it is characterized in that, comprise: cylinder pressure measuring device and pulse measure device, the cylinder pressure signal of collection and pulse signal corresponding to flywheel ring gear are sent to internal clock acquisition system by described cylinder pressure measuring device and pulse measure device, and the data of reception are sent to processor and process by described internal clock acquisition system further;

Within a processor, obtain by interpolation algorithm point and the zero crossing that pulse measure device output voltage is zero, obtain the time interval of adjacent two between cog according to the data of zero crossing, obtain the data of two arbitrarily angled correspondences of between cog further by interpolation algorithm.

2. the system in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 1, it is characterized in that, described cylinder pressure measuring device comprises cylinder pressure sensor, and described cylinder pressure sensor is arranged on engine cylinder and covers, and is connected to the firing chamber of engine by measuring pressure passage.

3. the system in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 1, it is characterized in that, described pulse measure device is arranged on engine flywheel end, during engine operation, each tooth of flywheel ring gear, through this sensor, all can produce a pulse signal by trigger sensor.

4. the system in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 1, it is characterized in that, described Pluse signal sensor is magnetoelectric sensor.

5. the system in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 1, it is characterized in that, described internal clock acquisition system be within the multi-channel high-speed data capture card of clock sampling mode work, the data transfer mode of multi-channel high-speed data capture card adopts USB interface or pci interface high speed data transmission interface.

6. the method in internal combustion engine cylinder pressure signal time domain gyration territory, is characterized in that, comprising:

Obtaining pulse measure device output voltage by interpolation algorithm is the point of 0 and moment Tstart and Tend of zero crossing;

Moment Tstart and Tend is duration corresponding to engine flywheel gear ring tooth between these two moment, angle corresponding between two moment of moment Tstart and Tend is the angular duration θ of a tooth;

According to the angular duration θ of two moment of Tstart and Tend, a tooth and cylinder pressure signal is converted into the angle intervals θ after angle domain by time domain _{interpolation interval}determine the time step T between angle domain cylinder pressure signal consecutive point _step;

According to sampling interval T _stepand work as first angle domain point that nipper interpolate value obtains and the angular deviation T worked as between nipper initial time Tstart _offand when nipper initial time Tstart obtains being converted into moment T corresponding to angle domain _n(n=0,1,2,3...);

According to the corresponding moment T of the angle domain obtained _n(n=0,1,2,3...), the in-cylinder pressure numerical value y of each point _n(n=0,1,2,3...) is obtained by 2 actual measurement cylinder pressure signal linear interpolations before and after this point.

7. the method in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 6, it is characterized in that, when the output voltage obtaining pulse measure device by interpolation algorithm is point and the zero crossing of 0, adopt 3 Newton interpolation methods, first each two points before and after zero crossing are obtained, (x ₀, y ₀), (x ₁, y ₁), (x ₂, y ₂) and (x ₃, y ₃), wherein, x ₀~ x ₃for the sampling sequence number of each sampled point, because four points are continuous print sampled point, the interval of adjacent spots all differs 1 sampled point moment; And y ₀~ y ₃then refer to the sampled result of before and after zero crossing 2, then x, y all in Newton interpolation formula are put upside down use, make y equal zero, obtain corresponding x value.

8. the method in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 6, is characterized in that, the number of teeth of angle θ: θ=360 ° of CA/ flywheel ring gears corresponding between two moment of moment Tstart and Tend.

9. the method in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 6, is characterized in that,

Interval time, difference was T _step:

In formula, θ is the angular duration of a flywheel ring gear tooth; θ _{interpolation interval}for the angle intervals being converted into angle domain of setting; T _startand T _endfor the zero crossing data obtained by interpolation.

10. the method in a kind of internal combustion engine cylinder pressure signal time domain gyration territory as claimed in claim 9, is characterized in that, the moment T that each point of angle domain is corresponding _nthe expression formula of (n=0,1,2,3...) is:

T _n＝T _start+n×T _step+T _off

In formula, T _offfor first the angle domain point obtained when nipper interpolate value and the angular deviation of working as between nipper initial time Tstart.