Multi-frequency m-level signal design method and system for frequency response measurement

Abstract

The invention discloses a multi-frequency m-level signal design method and system for frequency response measurement, and the method comprises the steps: generating an m-level signal composed of discrete levels which are uniformly distributed in an interval, maintaining the original amplitude structural characteristics of the signal, balancing the peak factor and inherent noise of the signal, and improving the hardware realizability of the signal; on the premise of meeting a user-specified measurement frequency point, rapid mapping from a continuous signal to a discrete level is realized, and the method is highly compatible with an existing multi-frequency signal optimization algorithm, is convenient to integrate into a complete multi-frequency signal design algorithm process, has good universality and expandability, is suitable for multi-frequency signal design in any specified frequency band, and has a wide application prospect. The method supports various measurement requirements, and has the advantages of simple algorithm structure, high implementation efficiency, easy engineering application and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of frequency response measurement, and particularly relates to a multi-frequency m-level signal design method and system for frequency response measurement. BACKGROUND

[0002] The frequency response measurement method is one of the key technologies in the modeling and stability analysis of power electronic systems. By injecting a known disturbance signal into the system and analyzing its response, the frequency domain impedance characteristics of the system can be obtained without understanding the internal structure and parameters of the system. This method is widely used in impedance modeling, resonance analysis and control loop debugging of power electronic devices such as inverters and grid interface devices.

[0003] Currently, there are various frequency response measurement techniques in the industry. Although the measurement devices used by these techniques are not exactly the same, the excitation signals used are mainly divided into two categories: single-frequency excitation method and multi-frequency excitation method. The former uses a sine wave as a disturbance signal, has good amplitude control ability, high measurement accuracy, and is suitable for strong nonlinear systems. However, since only one frequency point can be excited at a time, the overall testing process takes a long time, making it difficult to meet the demand for rapid measurement. In contrast, the multi-frequency excitation method significantly improves the measurement efficiency by exciting multiple frequency points at once, making it particularly suitable for online monitoring and system identification.

[0004] The industry has proposed various multi-frequency signal design methods such as Multisine, Maximum Length Binary Sequence (MLBS), Discrete Interval Binary Sequence (DIBS), etc. These signals can measure the frequency response information of multiple frequency points in one measurement, and have different peak factors, spectral characteristics, and system compatibility. The Multisine frequency response measurement multi-frequency m-level signal design signal has a clear frequency spectrum, concentrated energy, and only excites the system at the target frequency point, with excellent frequency domain characteristics. However, its time-domain waveform has a high peak value, which can easily affect the normal operation of the system when injected into the system under test; and it has high hardware requirements for the signal generator. The frequency spectrum distribution of the MLBS frequency response measurement multi-frequency m-level signal design signal cannot be completely specified by the user, and its frequency components are densely distributed throughout the frequency band, making it difficult to concentrate energy at specific target frequency points, thereby reducing the excitation strength at the target frequency. The DIBS frequency response measurement multi-frequency m-level signal design signal is known for its low peak factor, better system compatibility and injection strength, but it inevitably has non-target frequency components in its frequency spectrum, with high inherent noise and more likely to cause spectral aliasing in measurement.

[0005] These multi-frequency signals differ significantly in time and frequency domain characteristics, and the respective defects are difficult to avoid in different application scenarios, lacking a multi-frequency signal design method that can be flexibly designed under different system characteristics, measurement methods and measurement requirements to meet different needs. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a design method and system for multi-frequency m-level signals for frequency response measurement, which addresses the shortcomings of the prior art. This method solves the technical problems in existing frequency response measurements, such as: Multisine signals have controllable spectrum but high peak factor and are difficult to implement in hardware; MLBS signals have low peak factor but uncontrollable spectrum; and DIBS signals have good compatibility but high inherent noise and the presence of non-target frequency components.

[0007] The present invention adopts the following technical solution: A method for designing multi-frequency m-level signals for frequency response measurement includes the following steps: Input spectrum design parameters and number of discrete levels ; Based on the aforementioned spectrum design parameters, a set of frequency points to be tested is generated, a multisine signal is constructed, and the frequency points uniformly distributed in the interval [-1, 1] are calculated. Target Level ; Based on the obtained multisine signal, the multisine signal is discretized to obtain a sequence. ; will sequence The ordered sequence is obtained by sorting the values ​​in descending order of magnitude. }; Sorted sequence Divided into A subset; The first k All data points within a subset are assigned the target level. Generate m-level signals As an excitation signal for frequency response measurement.

[0008] Preferably, the spectrum design parameters include the user-inputted desired measurement frequency range. , , the total number of frequency points .

[0009] Preferably, the set of frequency points to be measured A specified number of frequency points distributed between the start and end frequencies. For containing A collection of elements.

[0010] Preferably, a multisine signal for:

[0011] in, For frequency, for each frequency corresponding amplitude and phase, for time variable.

[0012] Preferably, the sequence is:

[0013] wherein, is frequency, for each frequency corresponding amplitude and phase, is a time domain sequence.

[0014] Preferably, each frequency corresponding amplitude is specified by a user or set to 1.

[0015] Preferably, the ordered sequence is: .

[0016] Preferably, the target level is:

[0017] wherein, .

[0018] Preferably, the ordered sequence is divided into groups, the difference in the number of data points of each subset is ≤1.

[0019] In a second aspect, the embodiments of the present application provide a multi-frequency m-level signal design system for frequency response measurement, comprising: a construction module, inputting frequency spectrum design parameters and discrete level number , generating a set of frequency points to be measured based on the frequency spectrum design parameters, constructing a Multisine signal, and calculating target levels uniformly distributed in the interval [-1, 1]; a discretization module, discretizing the Multisine signal to obtain a sequence according to the obtained Multisine signal; an ordering module, ordering the sequence in descending order of amplitude to obtain an ordered sequence ; a division module, dividing the ordered sequence into subsets; an assignment module, assigning the kall data points in the subset are assigned the target level generating an m-level signal as a frequency response measurement excitation signal.

[0020] In a third aspect, a computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the above-mentioned frequency response measurement multi-frequency m-level signal design method when executing the computer program.

[0021] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium including a computer program, and the computer program implements the steps of the above-mentioned frequency response measurement multi-frequency m-level signal design method when executed by a processor.

[0022] In a fifth aspect, a chip includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps of the above-mentioned frequency response measurement multi-frequency m-level signal design method when executing the computer program.

[0023] In a sixth aspect, an embodiment of the present application provides an electronic device including a computer program, and the computer program implements the steps of the above-mentioned frequency response measurement multi-frequency m-level signal design method when executed by the electronic device.

[0024] Compared with the prior art, the present application has at least the following beneficial effects: A frequency response measurement multi-frequency m-level signal design method generates a Multisine signal based on a user-specified frequency point set, ensures that energy is accurately concentrated on target frequency points, avoids non-target frequency interference, maps continuous amplitude to discrete levels through descending order sorting and uniform grouping, significantly reduces signal peak value, and the current disturbance of the m-level signal is much smaller than that of the Multisine under the same energy, reduces the impact on the measured system. The number of discrete levels m can be flexibly configured, and the user can balance the noise and peak performance according to the demand. When m increases, the noise power ratio decreases, but the time factor increases; on the contrary, when m decreases, the peak is lower. The discrete levels are evenly distributed in [-1, 1], which adapts to the DAC resolution and improves the engineering realizability; and the length of the discrete sequence ensures that the quantization error is controllable. By replacing the traditional direct quantization with sorting, grouping and quantization, the high peak value and hardware limitations of the Multisine are broken through, and the spectral defects of the MLBS / DIBS are avoided while the spectral structure of the Multisine is retained.

[0025] Further, the spectral design parameters are used to create an initial spectrum, and the user only needs to input according to the basic measurement requirements; the number of required levels must satisfy , according to system characteristics, measurement method, hardware performance and measurement accuracy requirements; it conforms to the impedance frequency response characteristics of the power electronic system, distributes frequency points according to logarithmic density, improves low-frequency measurement accuracy, is compatible with communication system wideband measurement scenes, and embodies the generality of the method. Users can select a frequency point distribution mode according to the characteristics of the measured system to ensure that energy is concentrated in the key frequency band and waste of spectrum is avoided.

[0026] Further, the user can increase the signal-to-noise ratio at the resonance frequency point for a nonlinear system; or default to simplify the operation, compatible with existing phase optimization algorithms, further reduce the peak factor, while retaining the core discrete quantization framework, seamlessly integrated with the existing Multisine optimization process, and improve the signal synthesis performance.

[0027] Further, by flexible configuration, the embedded device and high-precision measurement requirements are considered, and the application scenarios are expanded.

[0028] Further, the difference between the data quantity of the m subsets is forced to ensure that the probability of using each discrete level is equal, avoid the level distribution skew caused by the capacity difference between groups, maintain the statistical properties of the signal, suppress the inherent noise, ensure the stability of the discrete mapping, and avoid introducing additional harmonic components by irregular grouping.

[0029] Further, the sorting module uses an efficient algorithm to meet the online measurement requirements, and the system can be integrated into the existing frequency response measurement device to directly output the m-level signal to drive the power amplifier, shortening the development cycle.

[0030] It can be understood that the beneficial effects of the above-mentioned second aspect to the sixth aspect can be referred to the related description in the first aspect, which will not be repeated here.

[0031] In summary, the present application considers the spectrum accurate controllable, low peak factor, low inherent noise, and adapts to different hardware conditions and measurement accuracy requirements of the multi-frequency signal design method.

[0032] The technical solutions of the present application will be further described in detail below with the help of the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The algorithm diagram of the multi-frequency m-level signal design method in the present application; Figure 2 The time domain and frequency domain comparison diagram of the 4-level and 8-level signals generated by the method proposed in the present application, wherein (a) is the time domain waveform, and (b) is the frequency domain energy; Figure 3 The signal time factor and noise power ratio of the m-level signal in the case of 2≤m≤10; Figure 4Figure 6 is an error comparison chart of frequency response measurement results of m-level signals generated by the method used in the experiment and conventional DIBS signals; Figure 5 Figure 5 is current waveforms of a phase and a phase of the system under the conditions of no disturbance injection, m-level disturbance injection and Multisine disturbance injection in the experiment, wherein (a) is no disturbance injection, (b) is M-level disturbance injection, and (c) is Multisine disturbance injection; Figure 6 Figure 1 is a schematic diagram of a computer device provided by an embodiment of the present application; Figure 7 Figure 2 is a block diagram of a chip provided by an embodiment of the present application.

[0034] In the figures, 60 is a computer device, 61 is a processor, 62 is a memory, 63 is a computer program, 600 is an electronic device, 610 is a processing unit, 620 is a storage unit, 6201 is a random access storage unit, 6202 is a cache storage unit, 6203 is a read-only storage unit, 6204 is a program / utility, 6205 is a program module, 630 is a bus, 640 is a display unit, 650 is an input / output interface, 660 is a network adapter, and 700 is an external device. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be clearly and completely described in connection with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0036] In the description of the present application, it should be understood that the terms “include” and “contain” indicate the presence of described features, whole, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, whole, steps, operations, elements, components and / or sets thereof.

[0037] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, unless otherwise clearly indicated by the context, the singular forms “a”, “an” and “the” are intended to include the plural forms.

[0038] It should also be further understood that the term "and / or" when used in the specification and in the following claims, is intended to mean an addition of one or more of the listed items to another item, as well as an addition of all possible combinations of the listed items. For example, A and / or B can mean A alone, A and B together, or B alone. In addition, the character " / " in the present application generally represents an "or" relationship between the objects before and after it.

[0039] It should be understood that, although the terms first, second, third, etc. can be used in embodiments of the present application to describe various ranges, etc., these ranges should not be limited to these terms. These terms are only used to distinguish one range from another. For example, a first range can be termed a second range without departing from the scope of the embodiments of the present application, and similarly, a second range can be termed a first range.

[0040] Depending on the context, the word "if" as used herein can be interpreted to mean "when" or "while" or "in response to determining" or "in response to detecting." Similarly, the phrase "if it is determined" or "if [a stated condition or event] is detected" can be interpreted to mean "upon determining" or "in response to determining" or "upon detecting [the stated condition or event]" or "in response to detecting [the stated condition or event]."

[0041] Various structural diagrams according to the disclosed embodiments of the present application are shown in the accompanying drawings. These diagrams are not drawn to scale, in which certain details are shown in a somewhat exaggerated manner for purposes of clarity and understanding, and certain details can be omitted. The shapes and relative sizes of the various regions, layers, and their relative positions shown in the drawings are merely exemplary, and in actuality, they can be deviated due to manufacturing tolerances or technical limitations, and a person skilled in the art can additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0042] The present application provides a multi-frequency m-level signal design for frequency response measurement, which generates a multi-frequency m-level signal design for frequency response measurement by discretely quantizing a traditional continuous-value multi-frequency m-level signal design for frequency response measurement Multisine multi-frequency m-level signal design for frequency response measurement The multi-frequency m-level signal design for frequency response measurement is uniformly distributed in the multi-frequency m-level signal design for frequency response measurement The frequency response measurement multi-frequency m-level signal design m-level frequency response measurement multi-frequency m-level signal design signal is designed by discrete levels in the interval, so that the peak factor, inherent noise of the signal is flexibly balanced while the original amplitude structure characteristics of the signal are maintained, and the hardware realizability of the signal is improved. The present application realizes the rapid mapping of continuous signals to discrete levels under the premise of meeting the user-specified measurement frequency points, and finally obtains a frequency response measurement multi-frequency m-level signal design multi-frequency signal design method which can be flexibly configured according to system characteristics, measurement method, hardware performance and measurement accuracy requirement. The present application is highly compatible with existing multi-frequency signal optimization algorithms (such as frequency point selection, amplitude distribution, etc.), is easy to integrate into a complete multi-frequency signal design algorithm process, and has good universality and expandability. The present application is suitable for multi-frequency signal design in any specified frequency band, supports various measurement requirements, and has the advantages of simple algorithm structure, high implementation efficiency, easy engineering application, etc.

[0043] Please refer to Figure 1 , the present application is a frequency response measurement multi-frequency m-level signal design method, comprising the following steps: S1, user input: spectrum design parameters , , ; required level ; The user inputs the spectrum design parameters: the starting frequency , the terminal frequency and the total number of frequency points , which are the three necessary preset parameters to determine the original measurement frequency point distribution.

[0044] The number of required levels: can be flexibly configured according to system characteristics, measurement method, hardware performance and measurement accuracy requirement.

[0045] S2, according to the input obtained in step S1, construct the target level corresponding to the measured frequency point set, Multisine signal and user required level ; The method of the present application uses user input to create a measurement frequency point set is the specified number of frequency points between the starting frequency and the terminal frequency, is a set containing elements. In order to meet the general needs of frequency response measurement, a logarithmic equidistant distribution is usually used. In fact, there is no strict requirement, and the method of the present application is also applicable to linear equidistant or other spectrum creation methods.

[0046] Calculate the Multisine signal containing the measurement frequency points:

[0047] where frequency , corresponding amplitude and phase, default to 1, which can also be specified by the user in the initial step, can be randomly assigned or obtained by the Multisine optimization algorithm.

[0048] Calculate the target level:

[0049] The purpose is to generate discrete levels uniformly distributed in interval.

[0050] S3, according to the Multisine signal obtained in step S2, calculate the discrete Multisine signal sequence; Discretize the Multisine signal to get the sequence:

[0051] The purpose is to obtain a discrete signal for subsequent processing.

[0052] where is the time domain sequence, the time length is related to the sampling speed, which is determined by the user according to the hardware performance and experimental accuracy, and need to meet .

[0053] S4, according to step S3, sort the sequence in descending order to get a new sequence }; Sort the sequence in descending order to get a new sequence }, which satisfies The purpose is to obtain the relative amplitude relationship of each data point of the signal.

[0054] S5, according to step S4, divide the sorted sequence data into subsets; Divide the sorted sequence into groups, each containing data points. Since is not an integer, the number of data points in each group needs to be appropriately rounded to ensure that the total number is still . Since ​The influence of this rounding operation on the overall signal characteristics can be ignored.

[0055] S6、According to step S2 and step S5, the data points in the first subset are assigned as , and a new sequence is obtained. The relative amplitude relationship of the signal is maintained, and the signal range is limited within discrete levels, the data in Multisine is reasonably quantized to discrete levels uniformly distributed in interval, and the influence of signal peak value on the overall peak factor is reduced.

[0056] S7、Output the generated m-level signal .

[0057] The method of the application realizes the synergistic optimization of controllable spectrum, low peak value and low noise in the frequency response measurement signal for the first time through the innovative "ordering grouping quantization" mechanism, and gives the user the ability to flexibly adjust the performance through the m value, and completely solves the three signal defects in the background technology. The system and device claims cover the software and hardware implementation, forming a complete technical closed loop.

[0058] In another embodiment of the application, a multi-frequency m-level signal design system for frequency response measurement is provided, which can be used to realize the multi-frequency m-level signal design method for frequency response measurement described above. Specifically, the multi-frequency m-level signal design system for frequency response measurement includes a construction module, a discrete module, an ordering module, a division module and an assignment module.

[0059] The construction module inputs the spectrum design parameters and the number of discrete levels , generates a set of frequency points to be measured based on the spectrum design parameters, constructs a Multisine signal, and calculates target levels uniformly distributed in the interval [-1, 1] ; The discrete module discretizes the Multisine signal based on the obtained Multisine signal to obtain a sequence ; The ordering module sorts the sequence in descending order of amplitude to obtain an ordered sequence }; The division module divides the ordered sequence into subsets; The assignment module assigns all data points in the first k subset to the target level generating an m-level signal as a frequency response measurement excitation signal.

[0060] The present application provides a terminal device, comprising a processor and a memory, the memory is used for storing a computer program, the computer program comprises program instructions, and the processor is used for executing the program instructions stored in the computer storage medium. The processor can be a central processing unit (CPU), and can also be other general-purpose processors, graphics processing units (GPU), tensor processing units (TPU), digital signal processors (DSP), application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, which is suitable for implementing one or more instructions, and is particularly suitable for loading and executing one or more instructions to implement a corresponding method process or a corresponding function. The processor in the embodiments of the present application can be used for the operation of the frequency response measurement multi-frequency m-level signal design method, including: inputting frequency spectrum design parameters and discrete level numbers ; generating a to-be-measured frequency point set based on the frequency spectrum design parameters, constructing a Multisine signal, and calculating target levels uniformly distributed in the interval [-1, 1] ; according to the obtained Multisine signal, discretizing the Multisine signal to obtain a sequence ; sorting the sequence in descending order of amplitude to obtain an ordered sequence }; and sorting the ordered sequence divided into subsets; assigning all data points in the k subset to a target level , generating an m-level signal as a frequency response measurement excitation signal.

[0061] Referring to Figure 6 , the terminal device is a computer device, the computer device 60 of this embodiment includes a processor 61, a memory 62, and a computer program 63 stored in the memory 62 and executable on the processor 61, and the computer program 63 implements the method for estimating the concentration of radioactive iodine species in the post-accident containment when executed by the processor 61, to avoid repetition, which will not be described here. Alternatively, the computer program 63 implements the functions of each model / unit in the system for designing a multi-frequency m-level signal for frequency response measurement when executed by the processor 61, to avoid repetition, which will not be described here.

[0062] The computer device 60 can be a desktop computer, a notebook, a palm computer, and a cloud server, etc. The computer device 60 can include, but is not limited to, the processor 61 and the memory 62. Those skilled in the art can understand Figure 6 that the computer device 60 is only an example and does not constitute a limitation on the computer device 60, and can include more or fewer components than those shown, or combine certain components, or different components, for example, the computer device can also include an input / output device, a network access device, a bus, etc.

[0063] The processor 61 can be a central processing unit (CPU), and can also be other general-purpose processors, graphics processing units (GPUs), tensor processing units (TPUs), digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0064] The memory 62 can be an internal storage unit of the computer device 60, such as a hard disk or a memory of the computer device 60. The memory 62 can also be an external storage device of the computer device 60, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc.

[0065] Further, the memory 62 can include both an internal storage unit and an external storage device of the computer device 60. The memory 62 is used to store computer programs and other programs and data required by the computer device. The memory 62 can also be used to temporarily store data that has been output or will be output.

[0066] Please refer to Figure 7The terminal device is an electronic device 600, which is in the form of a general computing device. Components of the electronic device can include, but are not limited to, at least one processing unit 610, at least one storage unit 620, a bus 630 that connects the various platform components, including the storage unit 620 and the processing unit 610, a display unit 640, and the like.

[0067] The storage unit stores program code that can be executed by the processing unit 610 to cause the processing unit 610 to perform the steps described in the method portion of the specification above in accordance with the various example embodiments of the present application. For example, the processing unit 610 can perform the steps shown in FIG. 6. Figure 1

[0068] The storage unit 620 can include a readable medium in the form of volatile storage such as a random access memory (RAM) 6201 and / or cache memory 6202, and can further include a read-only memory (ROM) 6203.

[0069] The storage unit 620 can also include program / utility 6204 having a set of at least one program modules 6205, including an operating system, one or more application programs, other program modules, and program data, each or some combination thereof, which can include implementation of a network environment.

[0070] The bus 630 can be representative of one or more of several types of bus structures, including a storage bus or bus controller, a peripheral bus, a graphics acceleration port, a processing unit, or a local bus using any of a variety of bus structures.

[0071] The electronic device 600 can also communicate with one or more external devices 700 such as a keyboard or pointing device, a Bluetooth device, etc.; other devices that enable a user to interact with the electronic device 600; and / or one or more devices that enable the electronic device 600 to communicate with one or more other computing devices. Such communication can be via the input / output interface 650. The electronic device 600 can further communicate with one or more networks (such as a local area network, a wide area network, and / or the public switched telephone network, such as the Internet) via a network adapter 660. The network adapter 660 can communicate with the other components of the electronic device 600 via the bus 630. It should be appreciated that although the network adapter 660 is shown as a single component, the network adapter 660 can comprise a plurality of components that work in cooperation to provide the functionality described herein. It should also be appreciated that although not shown, other hardware and / or software components that are commonly used in computing devices, such as microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data archival storage systems, etc. can be used with the electronic device 600.

[0072] ​Embodiment 4 The present application further provides a storage medium, specifically a computer readable storage medium, which is a memory device in the terminal device, used for storing programs and data. It can be understood that the computer readable storage medium herein can include the built-in storage medium in the terminal device, and of course can include the expansion storage medium supported by the terminal device, and can be any tangible medium containing or storing programs, which can be used by or in combination with the instruction execution system, device or apparatus. The computer readable storage medium provides a storage space, which stores the operating system of the terminal. Moreover, one or more instructions suitable for being loaded and executed by the processor are also stored in the storage space, which can be one or more computer programs (including program codes). It should be noted that more specific examples of the computer readable storage medium include an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical fiber, a portable compact disk read-only memory, an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0073] The computer readable storage medium further includes a data signal carried in the baseband or as a part of a carrier wave, in which readable program codes are borne. Such a propagated data signal can take various forms, including but not limited to electro-magnetic signal, optical signal or any suitable combination of the above. The readable storage medium can also be any readable medium other than the readable storage medium, which can send, propagate or transmit programs for use by or in combination with the instruction execution system, device or apparatus. The program codes contained in the readable storage medium can be transmitted by any suitable medium, including but not limited to wireless, wired, optical cable, radio frequency, etc. or any suitable combination of the above.

[0074] The program code for performing the operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device or entirely on the remote computing device or server. In the latter scenario, the remote computing device can be connected to the user's computing device through any type of network, including a local area network or a wide area network, or the connection can be made to an external computing device, such as through the Internet using an Internet Service Provider.

[0075] The one or more instructions stored in the computer readable storage medium can be loaded and executed by the processor to implement the corresponding steps of the method for designing a multi-frequency m-level signal for frequency response measurement in the above embodiments; the one or more instructions stored in the computer readable storage medium are loaded and executed by the processor to implement the following steps: inputting a frequency spectrum design parameter and a number of discrete levels ; generating a set of to-be-measured frequency points based on the frequency spectrum design parameter, constructing a Multisine signal, and calculating target levels uniformly distributed in the interval [-1, 1] ; discretizing the Multisine signal according to the obtained Multisine signal to obtain a sequence ; sorting the sequence in descending order of amplitude to obtain an ordered sequence ; dividing the sorted sequence into subsets; assigning all data points in the k subset to the target level , and generating an m-level signal as a frequency response measurement excitation signal.

[0076] The database involved in each of the embodiments provided in the present application can include at least one of a relational database and a non-relational database. The non-relational database can include a distributed database based on a blockchain, and the like, without being limited thereto. The processor involved in each of the embodiments provided in the present application can be a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, and the like, without being limited thereto.

[0077] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0078] Please refer to Figure 2The method generates a time domain and frequency domain comparison chart of the 4-level and 8-level signals. Under the same energy, the peak of the 8-level signal is higher, but the inherent noise in the frequency domain is small, and the nature is closer to Multisine. The 4-level signal contains more inherent noise, but the peak of the signal is low, and the influence on the measured system is small.

[0079] Please refer to Figure 3 The method generates a signal time factor and noise power ratio of the m-level signal under the condition of 2<=m<=10.

[0080] The time factor reflects the peak factor of the signal and the uniformity of the energy at each specified frequency point. Generally, the signal with small time factor has little influence on the normal operation of the measured system and should be given priority.

[0081] The noise power ratio can intuitively represent the influence of inherent noise. Generally, the signal with small noise power ratio contains less inherent noise in the frequency domain, and the influence of inherent noise on the expected measurement frequency point is smaller, and the measurement accuracy is higher. Therefore, the signal with small noise power ratio should be given priority.

[0082] According to Figure 3 it can be seen that with the increase of the number of signal levels, the noise power ratio gradually decreases, and the time factor gradually increases. The M-level signal provides a compromise between the two, and the appropriate number of levels can be selected flexibly according to the specific application scenario, measurement method and measurement requirements to obtain signals with different properties. When the number of signal levels exceeds 6, the change of noise power ratio and time factor tends to be slow, and the influence of increasing the number of levels on signal performance gradually weakens. Therefore, it is usually unnecessary to select a signal with more than 10 levels. In addition, for binary systems, signals with 2 levels help to improve storage and processing efficiency.

[0083] Please refer to Figure 4 The present application provides a comparison chart of the frequency response measurement error of the m-level signal generated by the method and the traditional DIBS signal in the experiment. The experiment measures the port impedance of a three-phase bridge rectifier with different multi-frequency signals. It should be noted that the present application can be used to design m-level multi-frequency signals with any number of levels, and 4-level and 8-level signals are used here only as an example; the m-level multi-frequency signal generated by the present application can be used to measure various linear and nonlinear systems, and the three-phase bridge rectifier port impedance is selected here only as an example.

[0084] Please refer to Figure 5The application provides current waveforms of a phase a and a phase b of a system under conditions of non-disturbance injection, m-level disturbance injection and Multisine disturbance injection in experiments. Figure 4 With Figure 5 It can be seen that the method has feasibility and advantages in actual frequency response measurement.

[0085] In summary, the application provides a multi-frequency m-level signal design method and system for frequency response measurement. m The Multisine signal is converted into m-level signals through discrete quantization, the peak factor is significantly reduced while the original frequency spectrum structure is reserved, the inherent noise can be controlled and adjusted, the number of levels can be flexibly configured according to hardware performance, engineering applicability is improved, multiple frequency points are covered by one injection, and the time-consuming defect of the single frequency method is overcome. m The spectrum energy is concentrated on the target frequency point, the aliasing error is reduced, the existing frequency point / amplitude optimization algorithm is compatible, the complete design process can be integrated, and the method is suitable for any frequency band.

[0086] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above functional units and modules is exemplified, and in actual application, the above functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above.

[0087] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in a certain embodiment can be referred to the relevant description of other embodiments.

[0088] Those skilled in the art can understand that the units and algorithm steps of each example described in combination with the embodiments disclosed in the present application can be realized in electronic hardware or in combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0089] In the embodiments provided by the present application, it should be understood that the disclosed apparatus / terminal and method can be implemented in other ways. For example, the apparatus / terminal embodiments described above are merely schematic. The division of the modules or units is merely a logical function division, and there can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed coupling or direct coupling or communication connection between the units can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or in other forms.

[0090] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e. they can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiments.

[0091] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically independently, or two or more units can be integrated into one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0092] The integrated module / unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiments of the method of the application can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer-readable storage medium. The computer program can be executed by a processor to implement the steps of each method embodiment described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (Read-Only Memory, ROM), random access memory (Random-Access Memory, RAM), electrical carrier signal, telecommunication signal, and software distribution medium, and the like. It should be noted that the contents included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0093] The present application is described with reference to flowcharts and / or block diagrams according to the methods, devices, and computer program products of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks

[0094] These computer program instructions can also be stored in a computer-readable memory that can guide the computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including instruction devices that implement the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks Figure 1 The functions specified in one or more flows and / or blocks

[0095] These computer program instructions can also be loaded into a computer or other programmable data processing devices, so that a series of operational steps are performed on the computer or other programmable data processing devices to generate a computer implemented process, so that the instructions executed on the computer or other programmable data processing devices provide a process for implementing the functions specified in the flowchart Figure 1 one flow or multiple flows and / or the functions specified in the block Figure 1 one block or multiple blocks.

[0096] The above is only to illustrate the technical idea of the present application, and cannot limit the protection scope of the present application. Any modification made according to the technical idea of the present application on the basis of the technical scheme falls within the protection scope of the claims of the present application.

Claims

1. A method for designing multi-frequency m-level signals for frequency response measurement, characterized in that, Includes the following steps: Input spectrum design parameters and number of discrete levels ; Based on the aforementioned spectrum design parameters, a set of frequency points to be tested is generated, a multisine signal is constructed, and the frequency points uniformly distributed in the interval [-1, 1] are calculated. Target Level ; Based on the obtained multisine signal, the multisine signal is discretized to obtain a sequence. ; will sequence The ordered sequence is obtained by sorting the values ​​in descending order of magnitude. }; Sorted sequence Divided into A subset; The first k All data points within a subset are assigned the target level. Generate m-level signals As an excitation signal for frequency response measurement.

2. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, Spectrum design parameters include the user-inputted desired measurement frequency range. , , the total number of frequency points .

3. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, Set of frequency points to be tested A specified number of frequency points distributed between the start and end frequencies. For containing A collection of elements.

4. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, Multisine signal for: in, For frequency, For each frequency The corresponding amplitude and phase, It is a time variable.

5. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, Multisine signal sequence for: in, For frequency, For each frequency The corresponding amplitude and phase, It is a time-domain sequence.

6. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 4, characterized in that, Each frequency Corresponding amplitude Specify by the user or set to 1.

7. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, ordered sequence }middle, .

8. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, Target level for: in, .

9. The method for designing multi-frequency m-level signals for frequency response measurement according to claim 1, characterized in that, Divide the sorted sequence into Group, The difference in the number of data points in each subset is ≤1.

10. A multi-frequency m-level signal design system for frequency response measurement, characterized in that, include: The module is constructed by inputting the spectrum design parameters and the number of discrete levels. Based on the aforementioned spectral design parameters, a set of frequency points to be tested is generated, a Multisine signal is constructed, and the frequency points uniformly distributed in the interval [-1, 1] are calculated. Target Level ; The discrete module discretizes the obtained multisine signal to obtain a sequence. ; The sorting module sorts the sequence. The ordered sequence is obtained by sorting the values ​​in descending order of magnitude. }; Divide the sequence into modules and sort the sequence. Divided into A subset; The assignment module will assign the first value to the second value. k All data points within a subset are assigned the target level. Generate m-level signals As an excitation signal for frequency response measurement.

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