CN114109798B

CN114109798B - Frequency determining method, frequency determining device, compressor system and storage medium

Info

Publication number: CN114109798B
Application number: CN202111423594.3A
Authority: CN
Inventors: 张鹏飞; 刘树清; 李田; 杨斌
Original assignee: Midea Group Co Ltd; GD Midea Heating and Ventilating Equipment Co Ltd
Current assignee: Midea Group Co Ltd; GD Midea Heating and Ventilating Equipment Co Ltd
Priority date: 2021-11-26
Filing date: 2021-11-26
Publication date: 2023-08-29
Anticipated expiration: 2041-11-26
Also published as: CN114109798A

Abstract

The invention provides a frequency determining method, a frequency determining device, a compressor system and a storage medium. The frequency determining method comprises the following steps: according to the P preset frequencies, respectively carrying out frequency test on the transmission system to obtain P amplitude values and P phase values; q target amplitudes are determined in the P amplitudes, and a first frequency corresponding to the target amplitudes is determined; determining a phase mutation frequency interval according to the P phase values; and determining the target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval. The embodiment of the invention provides an automatic identification method for bending mode frequency by combining online open loop amplitude frequency and phase frequency, which avoids the instability risk caused by the difference between offline bending mode frequency and online bending mode frequency, and can be suitable for different rotors, avoids the problem of low frequency debugging efficiency caused by the difference between online bending mode frequency of different rotors due to manufacturing assembly errors, and improves the debugging efficiency and accuracy.

Description

Frequency determining method, frequency determining device, compressor system and storage medium

Technical Field

The present invention relates to the field of compressor technology, and in particular, to a frequency determining method, a frequency determining apparatus, a compressor system, and a readable storage medium.

Background

The magnetic suspension bearing system of the compressor is unstable, the stability of the magnetic suspension bearing system can be realized by active feedback control, and the stable control of the bending mode is a precondition for system stability. In the related art, bending mode frequencies are usually obtained through an offline test, but due to the difference between offline and online bending mode frequencies of the magnetic bearing system, the system is at risk of instability.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

To this end, an aspect of the present invention is to propose a frequency determination method.

Another aspect of the present invention is to provide a frequency determining apparatus.

Yet another aspect of the present invention is to provide a compressor system.

Yet another aspect of the present invention is to provide a readable storage medium.

In view of this, according to one aspect of the present invention, there is provided a frequency determining method including: according to the P preset frequencies, respectively carrying out frequency test on the transmission system to obtain P amplitude values and P phase values; q target amplitudes are determined in the P amplitudes, and a first frequency corresponding to the target amplitudes is determined; determining a phase mutation frequency interval according to the P phase values; determining a target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval; wherein P, Q is a positive integer, P is greater than 1, and Q is less than P.

In the technical scheme, a frequency sweep interval set by a user and a frequency interval value set by the user are obtained, and P preset frequencies are determined according to the frequency sweep interval and the frequency interval value. And then, carrying out sweep frequency test on the transmission system, namely, carrying out frequency test on the transmission system once according to each preset frequency to obtain an amplitude frequency curve and a phase frequency curve, wherein the amplitude frequency curve corresponds to P amplitude frequency pairs, and the phase frequency curve corresponds to P phase frequency pairs.

And acquiring a target amplitude value from the P amplitude values, wherein the target amplitude value refers to a local peak value of an amplitude value frequency curve, and recording a corresponding preset frequency as a first frequency. That is, P amplitude frequency pairs, Q local peak amplitude frequency pairs are obtained. Through the mode, the primary screening of the frequency is realized.

Further, according to the P phase frequency pairs, a phase abrupt frequency interval, that is, a frequency interval in which the phase value changes greatly, is determined. And then the phase mutation frequency interval is utilized to further screen the first frequency to obtain the target frequency of the transmission system, so that the obtained frequency can be more accurate and the identification efficiency is higher.

The embodiment of the invention provides an automatic identification method for bending mode frequency by combining online open loop amplitude frequency and phase frequency, which avoids the instability risk caused by the difference between offline bending mode frequency and online bending mode frequency, and can be suitable for different rotors, avoids the problem of low frequency debugging efficiency caused by the difference between online bending mode frequency of different rotors due to manufacturing assembly errors, and improves the debugging efficiency and accuracy.

The above-described frequency determination method according to the present invention may further have the following additional technical features:

in the above technical solution, determining the target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval includes: acquiring second frequencies in a phase mutation frequency interval in the Q first frequencies; a target frequency of the driveline is determined based on the second frequency.

In the technical scheme, a first frequency falling in a phase mutation frequency interval is determined, the first frequency falling in the phase mutation frequency interval is recorded as a second frequency, and then a target frequency is obtained according to the second frequency.

Through the mode, the Q obtained first frequencies are further screened to obtain the target frequency of the transmission system, so that the obtained frequency can be more accurate, and the identification efficiency is higher.

In any of the above solutions, determining Q target magnitudes among the P magnitudes includes: calculating a first difference value of amplitude values corresponding to two adjacent preset frequencies, and determining a first symbol function value of the first difference value; calculating a second difference value of the two adjacent first symbol function values; and taking the amplitude corresponding to the second difference value which is equal to-2 as a target amplitude.

In the technical scheme, the difference value of the amplitudes of two adjacent preset frequencies in the P preset frequencies is determined and is recorded as a first difference value. And calculating a sign function value of each first difference value by using a sign function, and recording the sign function value as a first sign function value, wherein the first sign function value represents whether the first difference value is a positive value or a negative value, so that the amplitude change trend of two adjacent preset frequencies is obtained, namely, the amplitude corresponding to the latter preset frequency is increased or decreased compared with the amplitude corresponding to the former preset frequency in the two adjacent preset frequencies. For example, when the first sign function value is-1, it indicates that the first difference is a negative value, and the amplitude corresponding to the next preset frequency is reduced compared with the amplitude corresponding to the previous preset frequency; when the first symbol function value is 1, the first difference value is a positive value, and the amplitude corresponding to the next preset frequency is increased compared with the amplitude corresponding to the previous preset frequency; when the first symbol function value is 0, the first difference value is 0, and the amplitude corresponding to the latter preset frequency is equal to the amplitude corresponding to the former preset frequency.

Further, determining the difference value of two adjacent first symbol function values, recording the difference value as a second difference value, finding out the second difference value with the value equal to-2, and taking the amplitude value corresponding to the second difference value with the value equal to-2 as a target amplitude value. If the difference value of two adjacent first symbol function values is equal to-2, the next first symbol function value is-1, and the previous first symbol function value is 1, in this case, the amplitude change trend is shown to be increasing and then decreasing, and the amplitude frequency curve is in a local peak.

In the above manner, among the P amplitudes, the local peak value (i.e., the target frequency) of the amplitude frequency curve is determined, thereby providing a basis for obtaining an accurate bending mode frequency.

In any of the above solutions, taking the amplitude corresponding to the second difference value equal to-2 as the target amplitude includes: determining an amplitude corresponding to a second difference value equal to-2; and taking the amplitude value which is larger than or equal to the first threshold value as a target amplitude value.

In this solution, a further way of screening frequencies is defined. Specifically, after the magnitudes corresponding to the second difference value with the value equal to-2 are found, the magnitudes are screened by using a first threshold, for example, the magnitudes greater than or equal to the first threshold are determined as target magnitudes, that is, frequencies corresponding to the magnitudes less than the first threshold are removed, and only frequencies corresponding to the magnitudes greater than or equal to the first threshold are reserved.

Through the mode, the frequency smaller than the specific amplitude is removed, so that the obtained frequency can be more accurate, and the identification efficiency is higher.

In any of the above technical solutions, determining a phase mutation frequency interval according to P phase values includes: calculating the absolute value of the difference value of the phase values corresponding to the two adjacent preset frequencies, and marking the absolute value as a third difference value; calculating a fourth difference value between the third difference value and the second threshold value, and determining a second sign function value of the fourth difference value; calculating a fifth difference value of the function values of the two adjacent second symbols; and taking the frequency interval corresponding to the fifth difference value which is equal to-2 and the frequency interval corresponding to the fifth difference value which is equal to 2 as phase abrupt change frequency intervals.

In this technical solution, a way of determining the phase jump frequency interval is defined. Specifically, the absolute value of the difference value of the phase values of the adjacent two preset frequencies among the P preset frequencies is determined as the third difference value. And (3) performing difference between the third difference and a second threshold to obtain a fourth difference, wherein the second threshold is a preset phase change margin, for example, 40 degrees. And calculating a sign function value of each fourth difference value by using the sign function, and recording the sign function value as a second sign function value for determining whether the fourth difference value is a positive value or a negative value.

And further, the two adjacent second symbol function values are subjected to difference to obtain a fifth difference value, so that whether the phase values of the two adjacent preset frequencies have mutation or not is obtained. Specifically, when the fifth difference is equal to 2 and/or-2, it is indicated that the phase value is suddenly changed, including a sudden change in the upward direction (corresponding to the fifth difference being equal to 2) and a sudden change in the downward direction (corresponding to the fifth difference being equal to-2).

And finally, determining the frequency interval when the fifth difference value is equal to 2 and-2 as the phase mutation frequency interval.

Through the mode, the frequency interval of the phase mutation is accurately determined, so that the frequency is screened by utilizing the frequency interval of the phase mutation, and a basis is provided for obtaining accurate bending mode frequency.

In any of the above solutions, determining the target frequency of the transmission system according to the second frequency includes: obtaining N third frequencies, wherein the third frequencies are second frequencies with the amplitude being greater than or equal to a third threshold value, and N is a positive integer; searching the third frequency in a preset frequency range to correct the third frequency, and taking the corrected third frequency as a target frequency.

In this embodiment, the second frequency having the amplitude exceeding the third threshold value is used as the third frequency. Specifically, all the obtained second frequencies are sequenced according to the order of the amplitude values from large to small, and the first N amplitude values are taken, namely the amplitude values exceeding a third threshold value.

Further, by using a preset mode, the third frequency is locally searched in a preset frequency range, so that the correction of the third frequency is realized until the frequency error is smaller than a specified value. Finally, the corrected third frequency is set as the target frequency.

The embodiment of the invention provides a rapid and accurate identification method for local search of bending mode frequency, which improves the accuracy of frequency identification, thereby improving the reliability of the system.

According to another aspect of the present invention, there is provided a frequency determining apparatus comprising: the testing module is used for respectively carrying out frequency test on the transmission system according to P preset frequencies to obtain P amplitude values and P phase values; the first determining module is used for determining Q target amplitude values in the P amplitude values and determining a first frequency corresponding to the target amplitude values; the second determining module is used for determining a phase mutation frequency interval according to the P phase values; the third determining module is used for determining the target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval; wherein P, Q is a positive integer, P is greater than 1, and Q is less than P.

The above-described frequency determining apparatus according to the present invention may further have the following additional technical features:

in the above technical solution, the third determining module is specifically configured to obtain a second frequency in the phase abrupt change frequency interval from the Q first frequencies, and determine the target frequency of the transmission system according to the second frequency.

In any of the above embodiments, the frequency determining apparatus further includes: the first calculating module is used for calculating a first difference value of the amplitude values corresponding to the two adjacent preset frequencies, determining a first sign function value of the first difference value and calculating a second difference value of the two adjacent first sign function values; the first determining module is specifically configured to take, as the target amplitude, the amplitude corresponding to the second difference value equal to-2.

In any of the above solutions, the first determining module is specifically configured to determine an amplitude corresponding to the second difference value equal to-2, and use the amplitude greater than or equal to the first threshold as the target amplitude.

In any of the above embodiments, the frequency determining apparatus further includes: the second calculation module is used for calculating the absolute value of the difference value of the phase values corresponding to the two adjacent preset frequencies and recording the absolute value as a third difference value; calculating a fourth difference value between the third difference value and the second threshold value, and determining a second sign function value of the fourth difference value; calculating a fifth difference value of the function values of the two adjacent second symbols; the second determining module is specifically configured to use, as the phase abrupt change frequency interval, a frequency interval corresponding to a fifth difference value equal to-2 and a frequency interval corresponding to a fifth difference value equal to 2.

In any of the foregoing solutions, the third determining module is specifically configured to: obtaining N third frequencies, wherein the third frequencies are second frequencies with the amplitude being greater than or equal to a third threshold value, and N is a positive integer; searching the third frequency in a preset frequency range to correct the third frequency, and taking the corrected third frequency as a target frequency.

According to yet another aspect of the present invention, there is provided a compressor system comprising: a transmission system; a memory storing a program or instructions; a processor, wherein the processor performs the steps of the frequency determining method according to any one of the above-mentioned aspects when executing a program or instructions.

The compressor system provided by the invention realizes the steps of the frequency determination method according to any one of the technical schemes when the program or the instructions are executed by the processor, so that the compressor system comprises all the beneficial effects of the frequency determination method according to any one of the technical schemes.

According to yet another aspect of the present invention, there is provided a compressor system comprising: a transmission system; the frequency determining apparatus according to any one of the above aspects.

The compressor system provided by the invention is the frequency determining device of any one of the technical schemes, so that the compressor system comprises all the beneficial effects of the frequency determining device of any one of the technical schemes.

According to a further aspect of the present invention, there is provided a readable storage medium having stored thereon a program or instructions which when executed by a processor, perform the steps of the frequency determining method of any of the above-mentioned aspects.

The readable storage medium, program or instruction provided by the present invention, when executed by a processor, implements the steps of the frequency determining method according to any one of the above-mentioned technical solutions, so that the readable storage medium includes all the beneficial effects of the frequency determining method according to any one of the above-mentioned technical solutions.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 shows one of the flow diagrams of a frequency determination method of an embodiment of the present invention;

FIG. 2 is a second flow chart of a frequency determining method according to an embodiment of the invention;

FIG. 3 is a third flow chart of a frequency determining method according to an embodiment of the invention;

FIG. 4 is a flow chart of a method for determining frequency according to an embodiment of the present invention;

FIG. 5 is a fifth flow chart of a frequency determination method according to an embodiment of the present invention;

FIG. 6 is a flowchart of a frequency determining method according to an embodiment of the present invention;

FIG. 7 is a flow chart illustrating an online identification method of bending mode frequency of a magnetic bearing rotor according to an embodiment of the present invention;

FIG. 8 shows a schematic block diagram of a control system for a magnetic bearing rotor according to an embodiment of the invention;

FIG. 9 shows a schematic of an amplitude-frequency plot from p to q for an embodiment of the present invention;

FIG. 10 is a schematic diagram showing a p-to-q phase frequency curve and a phase abrupt frequency interval according to an embodiment of the present invention;

FIG. 11 illustrates a schematic diagram of candidate frequency value and amplitude pairs for an embodiment of the present invention;

FIG. 12 shows a schematic diagram of the first 3 rd order bending mode frequencies of an embodiment of the present invention;

fig. 13 shows a schematic block diagram of a frequency determining apparatus of an embodiment of the present invention;

FIG. 14 shows one of the schematic block diagrams of the compressor system of an embodiment of the present invention;

fig. 15 shows a second schematic block diagram of a compressor system of an embodiment of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

It should be noted that all directional indicators (such as up, down, left, right, front, and rear … …) in the embodiments of the present invention are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture (as shown in the drawings), and if the particular posture is changed, the directional indicator is changed accordingly.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical solutions of the embodiments of the present invention may be combined with each other, but it is necessary to be based on the fact that those skilled in the art can implement the technical solutions, and when the technical solutions are contradictory or cannot be implemented, the combination of the technical solutions should be considered as not existing, and not falling within the scope of protection claimed by the present invention.

The frequency determining method, the frequency determining device, the compressor system and the readable storage medium provided by the embodiment of the invention are described in detail below through specific embodiments and application scenes thereof with reference to the accompanying drawings.

Example 1

In the embodiment of the present invention, a frequency determining method is provided, and fig. 1 shows one of flow diagrams of the frequency determining method in the embodiment of the present invention. Wherein the method comprises the following steps:

102, respectively carrying out frequency test on a transmission system according to P preset frequencies to obtain P amplitude values and P phase values;

104, determining Q target amplitudes among the P amplitudes, and determining a first frequency corresponding to the target amplitudes;

step 106, determining a phase mutation frequency interval according to the P phase values;

step 108, determining the target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval.

Wherein P, Q are positive integers, and P is greater than 1 and Q is less than P.

It should be noted that the above-mentioned transmission system includes a compressor bearing system, for example, a magnetic suspension bearing system, and the compressor may be a centrifugal compressor. The frequency determination method can be applied to the bending mode of the bearing system of the compressor.

The method for determining P preset frequencies is not limited to the above method for determining equidistant frequencies, but may be obtained by logarithmic distribution of frequencies, and the like.

The number of target frequencies of the transmission system is not limited, and specifically, is determined according to the number of bending modes set by the user, for example, if the number of bending modes set by the user is N, the number of target frequencies is N.

Example two

In this embodiment, fig. 2 shows a second flowchart of the frequency determining method according to the embodiment of the present invention. Wherein the method comprises the following steps:

Step 202, determining P preset frequencies, and performing frequency test on a transmission system according to each preset frequency to obtain an amplitude frequency curve and a phase frequency curve, wherein the amplitude frequency curve corresponds to P amplitude frequency pairs, and the phase frequency curve corresponds to P phase frequency pairs;

step 204, obtaining Q target amplitudes from the P amplitudes, and marking the corresponding preset frequency as a first frequency;

step 206, according to the P phase values, obtaining a phase mutation frequency interval;

step 208, determining a first frequency falling within the phase mutation frequency interval, and recording the first frequency falling within the phase mutation frequency interval as a second frequency;

step 210, obtaining the target frequency of the transmission system according to the second frequency.

Example III

In this embodiment, fig. 3 shows a third flowchart of the frequency determining method according to the embodiment of the present invention. Wherein the method comprises the following steps:

step 302, determining P preset frequencies, and performing frequency test on the transmission system according to each preset frequency to obtain an amplitude frequency curve and a phase frequency curve, wherein the amplitude frequency curve corresponds to P amplitude frequency pairs, and the phase frequency curve corresponds to P phase frequency pairs;

step 304, determining the difference value of the amplitudes of two adjacent preset frequencies in the P preset frequencies, marking the difference value as a first difference value, calculating a symbol function value of each first difference value by using a symbol function, and marking the symbol function value as a first symbol function value;

step 306, determining the difference value of two adjacent first symbol function values, recording the difference value as a second difference value, finding out the second difference value with the value equal to-2, taking the amplitude corresponding to the second difference value with the value equal to-2 as a target amplitude, and recording the corresponding preset frequency as a first frequency;

step 308, according to the P phase values, obtaining a phase mutation frequency interval;

step 310, determining a first frequency falling within a phase mutation frequency interval, and recording the first frequency falling within the phase mutation frequency interval as a second frequency;

Step 312, obtaining the target frequency of the transmission system according to the second frequency.

Example IV

In this embodiment, fig. 4 shows a fourth flowchart of the frequency determining method according to the embodiment of the present invention. Wherein the method comprises the following steps:

step 402, determining P preset frequencies, and performing frequency test on the transmission system according to each preset frequency to obtain an amplitude frequency curve and a phase frequency curve, wherein the amplitude frequency curve corresponds to P amplitude frequency pairs, and the phase frequency curve corresponds to P phase frequency pairs;

Step 404, determining the difference value of the amplitudes of two adjacent preset frequencies among the P preset frequencies, and marking the difference value as a first difference value, and calculating a symbol function value of each first difference value by using a symbol function, and marking the symbol function value as a first symbol function value;

step 406, determining the difference value of two adjacent first symbol function values, recording the difference value as a second difference value, finding out a second difference value with the value equal to-2, and comparing the amplitude value corresponding to the second difference value with the value equal to-2 with a first threshold value;

step 408, determining the amplitude exceeding the first threshold value as a target amplitude, and recording the corresponding preset frequency as a first frequency;

step 410, according to the P phase values, obtaining a phase mutation frequency interval;

step 412, determining a first frequency falling within the phase abrupt frequency interval, and recording the first frequency falling within the phase abrupt frequency interval as a second frequency;

step 414, obtaining the target frequency of the transmission system according to the second frequency.

Example five

In this embodiment, fig. 5 shows a fifth flowchart of the frequency determining method according to the embodiment of the present invention. Wherein the method comprises the following steps:

step 502, determining P preset frequencies, and performing frequency test on the transmission system according to each preset frequency to obtain an amplitude frequency curve and a phase frequency curve, wherein the amplitude frequency curve corresponds to P amplitude frequency pairs, and the phase frequency curve corresponds to P phase frequency pairs;

step 504, obtaining Q target amplitudes from the P amplitudes, and marking the corresponding preset frequency as a first frequency;

step 506, determining the absolute value of the difference value of the phase values of two adjacent preset frequencies in the P preset frequencies as a third difference value, and making a difference between the third difference value and a second threshold value to obtain a fourth difference value;

step 508, calculating the sign function value of each fourth difference value by using the sign function, and marking the sign function value as a second sign function value, and taking the difference between two adjacent second sign function values to obtain a fifth difference value;

step 510, determining the frequency interval when the fifth difference is equal to 2 and-2 as the phase abrupt frequency interval;

Step 512, determining a first frequency falling within the phase mutation frequency interval, and recording the first frequency falling within the phase mutation frequency interval as a second frequency;

step 514, obtaining the target frequency of the transmission system according to the second frequency.

Example six

In this embodiment, fig. 6 shows a sixth flowchart of the frequency determining method according to the embodiment of the present invention. Wherein the method comprises the following steps:

step 602, determining P preset frequencies, and performing frequency test on the transmission system according to each preset frequency to obtain an amplitude frequency curve and a phase frequency curve, wherein the amplitude frequency curve corresponds to P amplitude frequency pairs, and the phase frequency curve corresponds to P phase frequency pairs;

step 604, obtaining Q target amplitudes from the P amplitudes, and marking the corresponding preset frequency as a first frequency;

step 606, according to the P phase values, obtaining a phase mutation frequency interval;

step 608, determining a first frequency falling within the phase mutation frequency interval, and recording the first frequency falling within the phase mutation frequency interval as a second frequency;

step 610, using the second frequency with the amplitude exceeding the third threshold as the third frequency, and performing local search on the third frequency within a preset frequency range to realize correction of the third frequency;

Step 612, determining the corrected third frequency as the target frequency of the transmission system.

In this embodiment, the frequency determining method further includes: and determining a preset frequency range of the third frequency according to the third frequency and the frequency interval value set by the user. Specifically, the preset frequency range is a third frequency±frequency interval value.

To improve the accuracy and rapidity of the identification, the frequency interval value should not be too large or too small, and the frequency interval value is set to be 5Hz to 20Hz, for example, 10Hz.

Example seven

In this embodiment, an online identification method of bending mode frequency of a magnetic bearing rotor is proposed. Fig. 7 is a flow chart illustrating an online identification method of bending mode frequency of a magnetic bearing rotor according to an embodiment of the present invention. Wherein the method comprises the following steps:

step 702, determining the number of bending modes, setting a frequency sweep interval and a frequency interval value, and determining a preset frequency according to the frequency sweep interval and the frequency interval value;

in this step, the number of bending modes N is determined, and the sweep interval F is set ₀ ，F ₁ ]And the frequency interval value delta f, the preset frequency of the sweep frequency is f _i ＝F ₀ ++ (i-1) Δf, where i=1, 2,..p, p= (F ₁ -F ₀ )/Δf+1。

Step 704, scanning the magnetic bearing rotor at the preset frequency to obtain a frequency curve and a phase frequency curve;

in this step, as shown in fig. 8, a small signal is injected into the magnetic bearing rotor at d with a preset frequency to sweep the frequency, where d represents the small signal injection terminal, p represents the open-loop input terminal, q represents the open-loop output terminal, and r represents the system input terminal in fig. 8. Obtain an amplitude-frequency curve (f) from p to q as shown in FIGS. 9 and 10 _i ，A _i ) Sum phase frequency curve

Step 706, calculating the sign function value of the amplitude difference between the adjacent preset frequencies, calculating the sign function difference between the adjacent preset frequencies, searching for an element with the sign function difference of-2, and storing the frequency value and the amplitude pair;

In this step, the sign function value a of the amplitude difference of adjacent preset frequencies is calculated _i ＝sign(ΔA _i ) Calculating the sign function difference delta a of adjacent preset frequencies _i Searching deltaa _i Element of = -2 and stores its frequency value and amplitude pair (f _j ，Δb _j ) These points are local peaks of the amplitude-frequency curve, as shown in fig. 9, marked by the "+" symbol. Δb is set forth in the specification _j Belonging to A _i Is a subset of the set of (c).

Step 708, calculating the sign function value of the difference value between the absolute value of the phase difference of the adjacent preset frequencies and the preset variation margin, calculating the difference value of the adjacent sign function values, respectively traversing and searching the elements with the difference value equal to 2 and the difference value equal to-2, storing the frequency values, and determining the frequency interval with the difference value equal to 2 and the difference value equal to-2 as the phase abrupt change frequency interval;

in this step, the absolute value of the phase difference between adjacent preset frequencies and the preset variation margin are calculatedSign function value of the difference of +.>Calculating adjacent θ _i Is respectively traversed by searching for delta theta _i = +2 and Δθ _i Element of = -2 and stores its frequency as two queues, Δθ _i = +2 and Δθ _i The frequency interval corresponding to = -2 is shown as the pulse interval of fig. 10.

Step 710, traversing the frequency value and amplitude pair with the symbol function difference value of-2, and if the frequency value in the frequency value and amplitude pair is in the phase abrupt frequency interval, storing the frequency value and amplitude pair;

In this step, the frequency value and amplitude pair (f _j ，Δb _j ) If f _j In the pulse interval shown in fig. 10, the candidate frequency value and amplitude pair (f _j ，Δb _j ) The stored local spikes are marked as "≡symbol" in fig. 11.

Step 712, the stored frequency value and amplitude value pairs are arranged in descending order, and the first N frequency value and amplitude value pairs are taken as the first N bending mode frequencies;

in this step, the magnitudes stored in step 710 are arranged in descending order, and after the first N frequency values and magnitude pairs are taken, the frequency values are arranged in ascending order, and the obtained frequency values and magnitude pairs are respectively the first N-order bending mode frequencies, as shown in fig. 12, and the "ζ" symbol is labeled as the first 3-order bending mode frequency.

Step 714, performing local search on the obtained N regions of the + -frequency interval values near the bending mode frequencies until each bending mode frequency error is smaller than a specified value;

in this step, a local search is performed for a region ±Δf around the bending mode frequency point obtained in step 712 by a dichotomy, golden section, or the like, until each bending mode frequency error is smaller than a predetermined value. It should be noted that, in order to improve accuracy and rapidity of identification, Δf should not be too large or too small, and Δf=10hz may be selected.

Example eight

In the frequency determining method provided by the embodiment of the invention, the execution body may be a frequency determining device, or a control module in the frequency determining device for executing the loading frequency determining method. In the embodiment of the present invention, a method for determining a loading frequency by using a frequency determining device is taken as an example, and the frequency determining device provided in the embodiment of the present invention is described. Fig. 13 shows a schematic block diagram of a frequency determining apparatus 1300 of an embodiment of the invention. Wherein, this frequency determination device 1300 includes: a test module 1302, a first determination module 1304, a second determination module 1306, and a third determination module 1308.

The test module 1302 can perform frequency test on the transmission system according to P preset frequencies to obtain P amplitude values and P phase values; the first determining module 1304 can obtain Q target magnitudes among the P magnitudes, and record a preset frequency corresponding to the Q target magnitudes as a first frequency; the second determining module 1306 can obtain a phase mutation frequency interval according to the P phase values; the third determination module 1308 is capable of obtaining a target frequency of the transmission system based on the first frequency and the phase abrupt frequency interval.

Example nine

In this embodiment, the third determining module 1308 is specifically configured to determine a first frequency that falls within a phase abrupt frequency interval, record the first frequency that falls within the phase abrupt frequency interval as a second frequency, and obtain a target frequency of the transmission system according to the second frequency.

Examples ten

In this embodiment, the frequency determining apparatus 1300 further includes: the first calculating module is used for determining the difference value of the amplitude values of two adjacent preset frequencies in P preset frequencies, marking the difference value as a first difference value, calculating a sign function value of each first difference value by using a sign function, marking the sign function value as a first sign function value, and determining the difference value of two adjacent first sign function values, marking the difference value as a second difference value; the first determining module 1304 is specifically configured to find a second difference value with a value equal to-2, and take an amplitude corresponding to the second difference value with a value equal to-2 as a target amplitude, and record a preset frequency corresponding to the target amplitude as the first frequency.

Example eleven

In this embodiment, the first determining module 1304 is specifically configured to compare the magnitude corresponding to the second difference value with a value equal to-2 with the first threshold, determine the magnitude exceeding the first threshold as the target magnitude, and record the corresponding preset frequency as the first frequency.

Example twelve

In this embodiment, the frequency determining apparatus further includes: a second calculation module for: determining the absolute value of the difference value of the phase values of two adjacent preset frequencies in the P preset frequencies, and taking the absolute value as a third difference value; the third difference value is subjected to difference with the second threshold value to obtain fourth difference values, and a sign function value of each fourth difference value is calculated by using a sign function and is recorded as a second sign function value; making a difference between two adjacent second symbol function values to obtain a fifth difference value; the second determining module 1306 is specifically configured to determine the frequency interval when the fifth difference is equal to 2 and-2 as the phase abrupt frequency interval.

Example thirteen

In this embodiment, the third determining module 1308 is specifically configured to: the second frequency with the amplitude exceeding a third threshold is used as a third frequency, and the third frequency is subjected to local search within a preset frequency range, so that the third frequency is corrected; the corrected third frequency is determined as the target frequency of the transmission system.

In this embodiment, the frequency determining apparatus further includes: and the fourth determining module is used for determining a preset frequency range of the third frequency according to the third frequency and the frequency interval value set by the user. Specifically, the preset frequency range is a third frequency±frequency interval value.

Examples fourteen

In an embodiment of the present invention, a compressor system is presented, and FIG. 14 shows one of the schematic block diagrams of a compressor system 1400 of an embodiment of the present invention. Wherein the compressor system 1400 comprises: a drive system 1402, a memory 1404, and a processor 1406. The memory 1404 is capable of storing a program or instructions that when executed by the processor 1406 implement the steps of the frequency determining method of any one of the above-described aspects.

Wherein the memory 1404 and the processor 1406 may be connected by a bus or other means. Processor 1406 may include one or more processing units, and processor 1406 may be a chip such as a central processing unit (Central Processing Unit, CPU), digital signal processor (Digital Signal Processor, DSP), application specific integrated circuit (Application Specific Integrated Circuit, ASIC), field programmable gate array (Field Programmable Gate Array, FPGA), or the like.

The compressor system 1400 provided by the present invention, when executed by the processor 1406, implements the steps of the frequency determination method of any of the above-described aspects, and therefore the compressor system 1400 includes all the advantages of the frequency determination method of any of the above-described aspects.

Example fifteen

In an embodiment of the present invention, a compressor system is provided, and fig. 15 shows a second schematic block diagram of a compressor system 1500 according to an embodiment of the present invention. Wherein the compressor system 1500 comprises: a transmission system 1502 and a frequency determining device 1300 according to any of the above-mentioned aspects.

The compressor system 1500 provided by the present invention comprises the frequency determining device 1300 according to any one of the above-mentioned aspects, and thus the compressor system 1500 comprises all the advantages of the frequency determining device 1300 according to any one of the above-mentioned aspects.

Examples sixteen

In an embodiment of the present invention, a readable storage medium is provided, on which a program or an instruction is stored, which when executed by a processor, implements the steps of the frequency determining method according to any one of the above-mentioned aspects.

Among them, the readable storage medium includes a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a magnetic disk or an optical disk, and the like.

The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of frequency determination, comprising:

according to the P preset frequencies, respectively carrying out frequency test on the transmission system to obtain P amplitude values and P phase values;

Q target amplitudes are determined in the P amplitudes, and a first frequency corresponding to the target amplitudes is determined;

determining a phase mutation frequency interval according to the P phase values;

determining a target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval;

wherein P, Q is a positive integer, P is greater than 1, and Q is less than P;

the determining Q target magnitudes among the P magnitudes includes:

calculating first difference values of amplitude values corresponding to two adjacent preset frequencies, and determining first symbol function values of the first difference values;

calculating a second difference value of two adjacent first symbol function values;

and taking the amplitude corresponding to the second difference value which is equal to-2 as the target amplitude.

2. The method of claim 1, wherein said determining a target frequency of the transmission system from the first frequency and the phase abrupt frequency interval comprises:

acquiring second frequencies in the phase mutation frequency interval in the Q first frequencies;

and determining the target frequency of the transmission system according to the second frequency.

3. The method according to claim 1, wherein said setting, as said target amplitude, an amplitude corresponding to said second difference value equal to-2, comprises:

Determining an amplitude corresponding to the second difference value equal to-2;

and taking the amplitude value which is larger than or equal to the first threshold value as the target amplitude value.

4. The method according to claim 1 or 2, wherein said determining a phase mutation frequency interval from said P phase values comprises:

calculating the absolute value of the difference value of the phase values corresponding to the two adjacent preset frequencies, and marking the absolute value as a third difference value;

calculating a fourth difference value between the third difference value and a second threshold value, and determining a second sign function value of the fourth difference value;

calculating a fifth difference value of two adjacent second symbol function values;

and taking the frequency interval corresponding to the fifth difference value which is equal to-2 and the frequency interval corresponding to the fifth difference value which is equal to 2 as the phase abrupt change frequency interval.

5. The method of claim 2, wherein determining the target frequency of the transmission system based on the second frequency comprises:

obtaining N third frequencies, wherein the third frequencies are the second frequencies with the amplitude being greater than or equal to a third threshold, and N is a positive integer;

searching the third frequency in a preset frequency range to correct the third frequency, and taking the corrected third frequency as the target frequency.

6. A frequency determining apparatus, comprising:

the testing module is used for respectively carrying out frequency test on the transmission system according to P preset frequencies to obtain P amplitude values and P phase values;

the first determining module is used for determining Q target amplitude values in the P amplitude values and determining a first frequency corresponding to the target amplitude values;

the second determining module is used for determining a phase mutation frequency interval according to the P phase values;

the third determining module is used for determining the target frequency of the transmission system according to the first frequency and the phase abrupt change frequency interval;

wherein P, Q is a positive integer, P is greater than 1, and Q is less than P;

the first calculating module is used for calculating a first difference value of the amplitude values corresponding to the two adjacent preset frequencies, determining a first sign function value of the first difference value and calculating a second difference value of the two adjacent first sign function values;

the first determining module is specifically configured to take, as the target amplitude, an amplitude corresponding to the second difference value equal to-2.

7. The apparatus of claim 6, wherein the device comprises a plurality of sensors,

the third determining module is specifically configured to obtain a second frequency in the phase abrupt change frequency interval from the Q first frequencies, and determine a target frequency of the transmission system according to the second frequency.

8. The apparatus of claim 6, wherein the device comprises a plurality of sensors,

the first determining module is specifically configured to determine an amplitude corresponding to the second difference value equal to-2, and use an amplitude greater than or equal to a first threshold value as the target amplitude.

9. The apparatus according to claim 6 or 7, further comprising:

the second calculation module is used for calculating the absolute value of the difference value of the phase values corresponding to the adjacent two preset frequencies and recording the absolute value as a third difference value;

the second determining module is specifically configured to determine a frequency interval corresponding to the fifth difference value equal to-2, and a frequency interval corresponding to the fifth difference value equal to 2, as the phase abrupt change frequency interval.

10. The apparatus of claim 7, wherein the third determining module is specifically configured to:

11. A compressor system, comprising:

a transmission system;

a memory storing a program or instructions;

a processor which when executing the program or instructions carries out the steps of the frequency determination method according to any one of claims 1 to 5.

12. A compressor system, comprising:

a transmission system;

the frequency determining apparatus according to any one of claims 6 to 10.

13. A readable storage medium having stored thereon a program or instructions, which when executed by a processor, implement the steps of the frequency determination method according to any of claims 1 to 5.