Wide frequency range repetition control method, inverter power supply, and storage medium

Abstract

The application provides a wide frequency range repetition control method, an inverter power supply and a storage medium. The method comprises the following steps: obtaining the number of repetition control points corresponding to the current time according to the frequency interval in which the current output frequency is located, wherein the number of repetition control points corresponding to the current time is the product of the maximum number of control points and a preset coefficient; compensating the amplitude of the current output voltage at each sampling point of the current period according to the repetition control data of the last period; and generating the repetition control data of the current period in real time according to the number of repetition control points corresponding to the current time, wherein the number of compensation amounts in the repetition control data of the last period and the repetition control data of the current period is the same as the maximum number of control points. According to the application, different ways are used to generate the repetition control data according to the frequency interval in which the voltage output frequency is located, so that the deviation between the actual number of repetition control points and the number of system sampling points is small while the continuity of the repetition control data is ensured.

Description

Technical Field

[0001] This invention relates to the field of inverter power supplies, and more specifically, to a wide-frequency-range repetitive control method, an inverter power supply, and a storage medium. Background Technology

[0002] As electronic devices place increasingly higher demands on power quality, high-performance inverters (such as UPS) are attracting more and more attention. When an inverter operates under load in steady state, harmonics caused by disturbances recur in each fundamental frequency cycle, affecting the power supply quality. To reduce harmonics in the inverter's output voltage, repetitive control technology is typically incorporated into the closed-loop system to compensate and correct the output waveform.

[0003] Existing repetitive control techniques typically employ a delay element with a delay time of T to construct the internal model of a periodic signal with an output voltage period of Tout, and embed it into the control loop. This enables static error-free tracking control or disturbance elimination of the periodic signal (including the sinusoidal output voltage and its harmonics).

[0004] The most commonly used repetitive control scheme currently employs a variable number of repetitive control points N and sampling points M, where N = M = Tout / Tsam, and N is the number of repetitive control points, M is the number of output voltage sampling points, Tout is the output voltage period, and Tsam is the fixed sampling period of the system. This means that both the number of repetitive control points N and the number of sampling points M vary at different output frequencies. This repetitive control scheme is highly dependent on the number of repetitive control points N. When the number of repetitive control points N is fixed, by selecting appropriate points and control parameters, the repetitive controller can achieve stable output and the control effect is ideal. However, for inverter power supplies with varying output voltage frequencies, especially those with large-scale variations, this scheme will lead to error accumulation due to the non-integer nature of the number of repetitive control points N at different output frequencies. This affects the compensation effect of the repetitive controller, increases the harmonic content of the inverter power supply, ultimately causing slow oscillations, and may even lead to instability in the adaptive repetitive control system.

[0005] Another repetitive control scheme uses a fixed number of repetitive control points N and sampling points M, where N = M = Tout / Tsam. It adjusts the system sampling period Tsam in real time according to the output voltage period Tout, thus fixing the number of repetitive control points N and sampling points M to avoid the aforementioned error accumulation. However, this scheme places high demands on system design. Generally, inverter hardware systems are designed based on a fixed switching frequency. A fixed switching frequency typically requires a fixed sampling frequency as well; otherwise, changes in the sampling frequency may cause significant deviations in the sampling of current signals containing high-frequency components. Furthermore, when the output voltage frequency changes (especially with rapid transitions), the transitions between the number of repetitive control points N and sampling points M require careful handling; otherwise, the control accuracy and stability of the entire inverter system will be affected.

[0006] Another repetitive control scheme uses a fixed number of repetitive control points N and a variable number of sampling points M. This means fixing the system sampling frequency and changing the number of sampling points M in real time according to the changes in the output voltage periodic frequency. Since inverter power supply control is based on the number of sampling points, the number of repetitive control points N must be greater than M. Only then can the inverter power supply interpolate the correct repetitive control compensation amount based on the correspondence between the current number of sampling points M and the number of repetitive control points N, thus ensuring the effectiveness of the repetitive control. In other words, the number of repetitive control points N must be selected based on the size of the system sampling points M. This method also has certain limitations; the deviation between the number of control points N and the variable number of sampling points M cannot be too large, meaning the output voltage frequency change cannot be too wide. Otherwise, the repetitive control compensation amount will be obtained entirely through interpolation, resulting in a significant deviation from the true periodic fluctuation signal, and the repetitive control effect will be less than ideal. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a wide frequency range repetitive control method, an inverter power supply and a storage medium, addressing the issue that the repetitive control effect of the above-mentioned repetitive control scheme is not ideal when the output voltage frequency changes.

[0008] The technical solution of the present invention to solve the above-mentioned technical problems is to provide a wide frequency range repetitive control method, comprising the following steps:

[0009] The number of repeating control points at the current moment is obtained based on the frequency range in which the current output frequency is located. The number of repeating control points at the current moment is the product of the maximum number of control points and a preset coefficient, wherein the preset coefficient is less than or equal to 1.

[0010] Based on the repetitive control data from the previous cycle, the amplitude of the current output voltage is compensated at each sampling point in the current cycle;

[0011] The repeating control data for the current cycle is generated in real time based on the number of repeating control points at the current moment. The number of compensation amounts in the repeating control data of the previous cycle and the repeating control data of the current cycle is the same as the maximum number of control points.

[0012] As a further improvement of the present invention, the maximum number of control points Nmax is an integer multiple of 360, and Tmax / Tsam≤Nmax≤Tmax / Tsam+360, where Tmax is the maximum period of the output voltage and Tsam is the sampling period.

[0013] As a further improvement of the present invention, when the current output frequency is in the first frequency range, the preset coefficient is 1, the repetition control point includes a first actual control point and a second actual control point, and the repetition control data of the current cycle includes the compensation amount of the first actual control point and the second actual control point.

[0014] The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes:

[0015] The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size.

[0016] The product of the real-time phase angle and Nmax / 360 is rounded down to the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array.

[0017] The interval points between the first actual control points are used as the second actual control points, and the compensation amount of the second actual control points is generated by interpolation.

[0018] As a further improvement of the present invention, when the current output frequency is in the second frequency range, the preset coefficient is one-half, the repetition control point includes a first actual control point and a second actual control point, and the repetition control data of the current cycle includes the compensation amount of the first actual control point, the compensation amount of the second actual control point and the compensation amount of the virtual control point.

[0019] The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes:

[0020] The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size.

[0021] The product of the real-time phase angle and Nmax / (360×2) is rounded down and multiplied by 2 to obtain the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array.

[0022] The even number of intervals between the first actual control points is taken as the second actual control point, and the compensation amount of the second actual control point is generated by interpolation.

[0023] The interval between the first actual control point and the second actual control point is used as a virtual control point, and the compensation amount of the previous first actual control point or the second actual control point is used as the compensation amount of the next virtual control point.

[0024] As a further improvement of the present invention, when the current output frequency is in the third frequency range, the preset coefficient is one-quarter, the repetition control point includes a first actual control point and a second actual control point, and the repetition control data of the current cycle includes the compensation amount of the first actual control point, the compensation amount of the second actual control point and the compensation amount of the virtual control point.

[0025] The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes:

[0026] The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size.

[0027] The product of the real-time phase angle and Nmax / (360×4) is rounded down and multiplied by 4 to obtain the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array.

[0028] The interval between the first actual control points is a multiple of 4, which is taken as the second actual control point, and the compensation amount of the second actual control point is generated by interpolation.

[0029] The interval between the first and second actual control points is used as virtual control points, and the compensation amount of the previous first or second actual control point is used as the compensation amount of the last three virtual control points.

[0030] As a further improvement of the present invention, when the current output frequency is in the fourth frequency range, the preset coefficient is one-eighth, the repetition control point includes a first actual control point and a second actual control point, and the repetition control data of the current cycle includes the compensation amount of the first actual control point, the compensation amount of the second actual control point and the compensation amount of the virtual control point.

[0031] The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes:

[0032] The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size.

[0033] The product of the real-time phase angle and Nmax / (360×8) is rounded down and multiplied by 8 to obtain the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array.

[0034] The interval between the first actual control points is a multiple of 8, which is taken as the second actual control point, and the compensation amount of the second actual control point is generated by interpolation.

[0035] The interval between the first and second actual control points is used as virtual control points, and the compensation amount of the previous first or second actual control point is used as the compensation amount of the last seven virtual control points.

[0036] As a further improvement of the present invention, the step of compensating the amplitude of the current output voltage at each sampling point of the current cycle based on the repetitive control data of the previous cycle includes:

[0037] The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size.

[0038] At each real-time phase angle position, the sum of the p-th compensation value obtained from the repetitive control data of the previous cycle and the standard voltage at the real-time phase angle is used to control the current output voltage, where p is the integer product of the real-time phase angle and Nmax / 360.

[0039] As a further improvement of the present invention, the number of repetitive control points in any frequency range is twice the number of repetitive control points in the adjacent high frequency range, and the number of repetitive control points corresponding to the current moment is not less than the quotient of the output voltage period and the sampling period.

[0040] The endpoint frequency f of the nth frequency interval satisfies: f = fsam / (Nmax × 2) -n+1 ×k), where fsam is the sampling period, k is a preset parameter and 0 < k < 1, and n is an integer greater than or equal to 2.

[0041] The present invention also provides an inverter power supply, comprising: a digital controller and a memory communicatively connected to the digital controller; wherein the memory stores instructions executable by the digital controller, the instructions being executed by the digital controller to enable the digital controller to perform the wide frequency range repetitive control method as described above.

[0042] The present invention also provides a computer-readable storage medium storing computer-executable instructions for causing a computer to perform the wide frequency range repetitive control method described above.

[0043] The present invention has the following beneficial effects: By generating repetitive control data in different ways according to the frequency range of the voltage output frequency, the continuity of the repetitive control data can be guaranteed while ensuring that the deviation between the number of repetitive control points and the number of system sampling points is small, thereby ensuring that the output harmonic content is low over a wide frequency range. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating the wide frequency range repetitive control method provided in an embodiment of the present invention;

[0045] Figure 2 This is a flowchart illustrating the process of generating repetitive control data in the first frequency range using the wide frequency range repetitive control method provided in this embodiment of the invention.

[0046] Figure 3 This is a schematic diagram of the repetitive control data generated in the first frequency range by the wide frequency range repetitive control method provided in the embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of the process of generating repetitive control data in the second frequency range using the wide frequency range repetitive control method provided in this embodiment of the invention.

[0048] Figure 5 This is a schematic diagram of the repetitive control data generated in the second frequency range by the wide frequency range repetitive control method provided in the embodiment of the present invention;

[0049] Figure 6 This is a flowchart illustrating the process of generating repetitive control data in the third frequency range using the wide frequency range repetitive control method provided in this embodiment of the invention.

[0050] Figure 7 This is a schematic diagram of the repetitive control data generated in the third frequency range by the wide frequency range repetitive control method provided in this embodiment of the invention.

[0051] Figure 8 This is a schematic diagram of the process of generating repetitive control data in the fourth frequency range using the wide frequency range repetitive control method provided in this embodiment of the invention.

[0052] Figure 9 This is a schematic diagram of the repetitive control data generated in the fourth frequency range by the wide frequency range repetitive control method provided in the embodiments of the present invention. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0054] like Figure 1 The diagram shown is a flowchart of a wide-frequency-range repetitive control method provided in an embodiment of the present invention. This wide-frequency-range repetitive control method can be applied to inverter power supplies (such as UPS, inverters, etc.) and reduces harmonics in the output voltage of the inverter power supply. The wide-frequency-range repetitive control method in this embodiment can be executed by power electronic equipment such as inverter power supplies and includes the following steps:

[0055] Step S10: Obtain the number N of repeated control points corresponding to the current time according to the frequency range of the current output frequency. The number N of repeated control points corresponding to the current time is the product of the maximum number of control points Nmax and the preset coefficient, and the preset coefficient is less than or equal to 1.

[0056] Specifically, when this method is applied to an inverter, the current output frequency is the frequency of the inverter's current output voltage, and each frequency interval corresponds to a frequency range of the inverter's output voltage. For example, when the inverter's output frequency varies within the range of 10Hz-100Hz, this range can be divided into multiple consecutive intervals. If the current output frequency is greater than or equal to the starting frequency (i.e., the lowest frequency) and less than the ending frequency (i.e., the highest frequency) of a certain frequency interval, then the current frequency is confirmed to be within that frequency interval.

[0057] The maximum number of control points, Nmax, corresponds to the total number of compensation values ​​within a voltage output cycle. This maximum number of control points remains constant even if the frequency of the power supply output voltage changes. The repetitive control data for each voltage output cycle can be stored in an array, where the i-th data point stores the i-th compensation value. The repetitive control data is refreshed based on the current number of repetitive control points, N, corresponding to the sampling points M within a voltage output cycle.

[0058] When the frequency of the power supply output voltage changes, the number of repetitive control points N also changes. For example, when the frequency of the power supply output voltage increases, the number of repetitive control points N decreases. Furthermore, when the frequencies of the power supply output voltages are within the same frequency range, the number of repetitive control points N corresponding to these voltage frequencies is the same.

[0059] Step S20: Based on the repetitive control data of the previous cycle, compensate the amplitude of the current output voltage at each sampling point in the current cycle.

[0060] In this step, at each sampling point of the current cycle, the corresponding compensation amount is obtained from the repetitive control data of the previous cycle to compensate for the amplitude of the current voltage. The repetitive control data of the previous cycle is generated by the inverter power supply during the voltage output process of the previous cycle. Since the amplitude of the inverter power supply output voltage generally does not change much between the two cycles, using the repetitive control data of the previous cycle to compensate for the output voltage of the current cycle can reduce the harmonics of the output voltage of the current cycle to a certain extent.

[0061] The number of sampling points M in the current period is related to the frequency of the current output voltage. Specifically, the number of sampling points M in the current period is M = Tout / Tsam, where Tout is the period of the current output voltage and Tsam is the system's fixed sampling period (e.g., the interrupt period of the control software). For example, when the period of the current output voltage is 1 / 10 second (corresponding to a frequency of 10Hz) and the system's fixed sampling period is 1 / 10000 second (corresponding to a frequency of 10000Hz), the number of sampling points M in the current period is 1000.

[0062] Step S30: Generate the repeating control data for the current cycle in real time based on the number of repeating control points at the current moment. The number of compensation values ​​in the repeating control data of the previous cycle and the repeating control data of the current cycle are the same as the maximum number of control points. The generated repeating control data for the current cycle can directly overwrite the repeating control data of the previous cycle.

[0063] In this step, a corresponding strategy is adopted based on the number of repetitive control points at the current moment, and the repetitive control data for the current cycle is created by combining this strategy with the actual output voltage of the current cycle. That is, the strategy for creating the repetitive control data for the current cycle differs depending on the number of repetitive control points. Furthermore, the number of compensation values ​​in the generated repetitive control data for the current cycle is the same, consistently matching the maximum number of control points, Nmax.

[0064] The above-mentioned wide-frequency-range repetitive control method generates repetitive control data in different ways according to the frequency range in which the voltage output frequency is located. While ensuring the continuity of the repetitive control data, it can also ensure that the deviation between the number of repetitive control points and the number of system sampling points is small, thereby making the output harmonic content low over a wide frequency range.

[0065] In one embodiment of the present invention, considering that the inverter output voltage is controlled by wave generation based on the real-time phase angle, with a phase angle range of 0-359 degrees, the number of repetitive control points N is chosen to be a multiple of 360. This is beneficial for the control system to calculate the repetitive control compensation amount based on the real-time phase angle. Specifically, the maximum number of control points Nmax is an integer multiple of 360, and Tmax / Tsam ≤ Nmax ≤ Tmax / Tsam + 360, where Tmax is the maximum period of the inverter output voltage, and Tsam is the system sampling period (for example, it can be the interrupt period of the control software). For example, when the output frequency of the inverter is 10-100Hz and the system sampling frequency fsam is 10000Hz, Tmax / Tsam = 10000 / 10 = 1000, therefore Nmax = 360 × 3 = 1080 is chosen.

[0066] In one embodiment of the present invention, the number of repetitive control points in any frequency range is twice the number of repetitive control points in the adjacent high frequency range, and the number of repetitive control points in the current period is not less than the quotient of the output voltage period and the sampling period.

[0067] The starting frequency f of the nth frequency interval satisfies: f = fsam / (Nmax × 2) -n+1 ×k), where fsam is the sampling period, k is a preset parameter and 0 < k < 1, and n is an integer greater than or equal to 2.

[0068] Combination Figure 2 In one embodiment of the present invention, when the current output frequency is in a first frequency range, the preset coefficient is 1, and the repetition control points include a first actual control point (first repetition control point) and a second actual control point (second repetition control point). Correspondingly, the repetition control data for the current period generated in step S30 includes the compensation amounts for the first and second actual control points. Specifically, the repetition control data for the current period generated in real time in step S30 according to the number of repetition control points at the current moment includes:

[0069] Step S311: Determine the phase angle change step size θ of the current period based on the number of sampling points in the current period, and obtain the real-time phase angle based on the phase angle change step size θ.

[0070] Step S312: The product of the real-time phase angle θ and Nmax / 360 is rounded down to the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array.

[0071] Step S313: Use the interval points between the first actual control points as the second actual control points, and generate the compensation amount of the second actual control points through interpolation. Specifically, the average of the two compensation amounts before and after the second control point can be used as the compensation amount of the second actual control point.

[0072] For example, when the inverter output frequency is 10-100Hz and the system sampling frequency fsam is 10000Hz, the number of sampling points in the current cycle, M1 = Tout / Tsam = 1000, and the number of repetitive control points N at the current moment is the maximum number of control points, Nmax = 1080. Correspondingly, the phase angle change step size θ = 0.36°, that is, the real-time phase angle θ of the m-th sampling point = 0.36 × m. Combined with... Figure 3 As shown, the real-time phase angle at the initial moment is 0, and the real-time phase angles of subsequent sampling points are 0.36°, 0.72°, 1.08°, etc. At the same time, the sequence number of the sampling point corresponding to the current cycle repetitive control data area is obtained by rounding up to 3 times the real-time phase angle θ (because the number of repetitive control points N1 corresponding to the current moment is 360 times).

[0073] For example, when the real-time phase angle θ of the control point is 0.36°, its three times is 1.08, which is rounded down to 1. In step S312, the repetitive control compensation amount calculated based on the real-time phase angle is stored in the array at position 1. When the real-time phase angle θ of the control point is 2.16°, its three times is 6.48, which is rounded down to 6. In step S312, the repetitive control compensation amount calculated based on the real-time phase angle is stored in the array at position 6. When the real-time phase angle θ of the control point is 2.52°, its three times is 7.56, which is rounded down to 8. In step S312, the repetitive control compensation amount calculated based on the real-time phase angle is stored in the array at position 8. The area between the compensation amounts at positions 6 and 8, i.e., the compensation amount at position 7, is used as the second actual control point, and the compensation amount is calculated by interpolation, for example, it can be the average of the compensation amounts at positions 6 and 8. By using the above method, 1080 compensation values ​​can be obtained in sequence. These 1080 compensation values ​​are the repetitive control data for the current cycle, which serve as the basis for compensation in the next output voltage cycle.

[0074] Combination Figure 4 As shown, in one embodiment of the present invention, when the current output frequency is in the second frequency range, the preset coefficient is 1 / 2, and its repetition control point includes a first actual control point (first repetition control point) and a second actual control point (second repetition control point). That is, the repetition control data of the current cycle generated in step S30 includes the compensation amount of the first actual control point, the compensation amount of the second actual control point, and the compensation amount of the virtual control point.

[0075] Specifically, in the above step S30, generating the repetitive control data of the current cycle in real time according to the number of repetitive control points corresponding to the current moment includes:

[0076] Step S321: Determine the phase angle variation step size of the current cycle according to the number of sampling points in the current cycle, and obtain the real-time phase angle according to the phase angle variation step size.

[0077] Step S322: Take the integer of the product of the real-time phase angle and Nmax / (360×2) and multiply it by 2 as the first actual control point, and store the repetitive control compensation amount data calculated based on the real-time phase angle in the position of the first actual control point in the array.

[0078] Step S323: Take the even numbers spaced between the first actual control points as the second actual control points, and generate the compensation amount for the second actual control points by means of interpolation.

[0079] Step S324: Take the interval points between the first actual control points and the second actual control points as virtual control points, and use the compensation amount of the previous first actual control point or second actual control point as the compensation amount of the subsequent virtual control point.

[0080] Also taking an inverter power supply with an output frequency of 10-100Hz and a system sampling frequency fsam of 10000Hz as an example, if the current output frequency is in the second frequency interval, the number of repetitive control points N2 of the repetitive control data in the output voltage cycle is half of the maximum number of control points Nmax, that is, N2=1080 / 2=540. The number of sampling points M2 in the current cycle is obtained by multiplying the number of repetitive control points N2 by a coefficient k (which can be set according to experimental data or experience, 0.5<k<1). For example, when k=0.8 (other parameters can also be selected), M2=k×N2=540×0.8=432, and the corresponding starting frequency of this second frequency interval is f1=fsam / M2=23.15Hz (correspondingly, the first frequency interval is 10Hz to 23.15Hz, that is, when the output frequency is below 23.15Hz, the repetitive control data is generated according to steps S311 to S313, and when the output frequency is above 23.15Hz, the repetitive control data is generated according to steps S321 to S324.

[0081] When the frequency of the output voltage is 23.15Hz, the phase angle variation step size of the current cycle calculated in step S321 is 0.83°, that is, the real-time phase angle θ of the m-th sampling point is θ=0.83×m. With reference to the accompanying drawings in the specification Figure 5At the initial moment, the real-time phase angle is 0. The real-time phase angles of subsequent sampling points are 0.83°, 1.67°, 2.5°, etc. At the same time, the sequence number of the sampling point corresponding to the current cycle repetitive control data area is obtained by rounding down the real-time phase angle θ by 1.5 times (because the number of repetitive control points N' is 1.5 times 360).

[0082] For example, when the real-time phase angle θ = 0.83°, its value is rounded down to 1, then multiplied by 2 to get 2. In step S322, the repetitive control compensation amount calculated based on the real-time phase angle θ = 0.83° is stored in the array at position 2. When the real-time phase angle θ = 1.67°, its value is rounded down to 3, then multiplied by 2 to get 6. In step S312, the repetitive control compensation amount calculated based on the real-time phase angle θ = 1.67° is stored in the array at position 6. The area between the compensation amounts at positions 2 and 6, i.e., the compensation amount at position 4, is used as the second actual control point, and the compensation amount is calculated using interpolation, for example, it could be the average of the compensation amounts at positions 6 and 8. The compensation amounts with odd numbers in the repetitive control data are used as virtual control points, directly using the compensation amount with the previous even number, such as... Figure 5 As shown. By using the above method, 1080 compensation values ​​can be obtained in sequence. These 1080 compensation values ​​are the repetitive control data for the current cycle, which serve as the basis for compensation in the next output voltage cycle.

[0083] Using the above method, all compensation values ​​stored in the repetitive control data can be recalled within this frequency range. Compensation values ​​with odd-numbered sequences directly use the previous compensation value with an even-numbered sequence, which is beneficial for recalling repetitive control data when the output frequency changes beyond the frequency range, thus preventing excessive deviations.

[0084] Combination Figure 6 As shown, in one embodiment of the present invention, when the current output frequency is in the third frequency range, the preset coefficient is 1 / 4, and the repetition control point includes a first actual control point (first repetition control point) and a second actual control point (second repetition control point). That is, the repetition control data of the current cycle in step S30 includes the compensation amount of the first actual control point, the compensation amount of the second actual control point, and the compensation amount of the virtual control point. Accordingly, the repetition control data of the current cycle is generated in real time according to the number of repetition control points at the current moment in step S30, including:

[0085] Step S331: Determine the phase angle change step size for the current period based on the number of sampling points in the current period, and obtain the real-time phase angle based on the phase angle change step size.

[0086] Step S332: The product of the real-time phase angle and Nmax / (360×4) is rounded and then multiplied by 4 to serve as the first actual control point, and the repetitive control compensation amount data calculated based on the real-time phase angle is stored at the position of the first actual control point in the array.

[0087] Step S333: A multiple of 4 spaced between the first actual control points is taken as a second actual control point, and the compensation amount for the second actual control point is generated by means of interpolation.

[0088] Step S334: Interval points between the first actual control points and the second actual control points are taken as virtual control points, and the compensation amount of the previous first actual control point or second actual control point is taken as the compensation amount for the subsequent three virtual control points.

[0089] Also taking an inverter power supply with an output frequency of 10-100Hz and a system sampling frequency fsam of 10000Hz as an example, if the current output frequency is in the third frequency interval, the number of repetitive control points N3 of the repetitive control data for the output voltage cycle is one quarter of the maximum number of control points Nmax (that is, one half of the number of repetitive control points N2 in the second frequency interval), that is, N3=1080 / 4=270, and the number of sampling points M3 in the current cycle is obtained by multiplying the number of repetitive control points N3 by a coefficient k (which can be set according to experimental data or experience, 0.5<k<1). For example, if k=0.8 (other parameters can also be selected), then M3=k×N3=270×0.8=216, and the corresponding starting frequency of this third frequency interval is f2=fsam / M3=46.3Hz (correspondingly, the second frequency interval is 23.15Hz to 46.3Hz, that is, when the output frequency is between 23.15Hz and 46.3Hz, the repetitive control data is generated according to steps S321 to S324, and when the output frequency is above 46.3Hz, the repetitive control data is generated according to steps S331 to S334.

[0090] When the frequency of the output voltage is 46.3Hz, the phase angle change step of the current cycle calculated in step S331 is 1.67°, that is, the real-time phase angle θ of the m-th sampling point is θ=1.67×m. With reference to the accompanying drawings of the specification Figure 7 , the real-time phase angle at the starting moment is 0, and the real-time phase angles of subsequent sampling points are 1.67°, 3.34°, 5.01°, etc. in sequence. At the same time, the serial number of the corresponding sampling point stored in the repetitive control data area of the current cycle is obtained by rounding (rounding off) 0.75 times (since the number of repetitive control points N' at this time is 0.75 times of 360) of the real-time phase angle θ.

[0091] For example, when the real-time phase angle θ = 1.67°, its value is rounded down to 0.75, which equals 1. Multiplying this by 4 gives 4. In step S332, the repetitive control compensation data calculated based on the real-time phase angle θ = 1.67° is stored in the array at position 4. When the real-time phase angle θ = 3.34°, its value is rounded down to 0.75, which equals 3. Multiplying this by 4 gives 12. In step S332, the repetitive control compensation data calculated based on the real-time phase angle θ = 3.34° is stored in the array at position 12. The compensation value at position 8, which is a multiple of 4 between the compensation values ​​at positions 4 and 12, is used as the second actual control point. The compensation value is calculated using interpolation, for example, the average of the compensation values ​​at positions 4 and 12. Compensation values ​​in the repetitive control data that are not multiples of four are used as virtual control points, directly using the compensation value of the previous multiple of four. Figure 7 As shown. By using the above method, 1080 compensation values ​​can be obtained in sequence. These 1080 compensation values ​​are the repetitive control data for the current cycle, which serve as the basis for compensation in the next output voltage cycle.

[0092] Using the above method, all compensation values ​​stored in the repetitive control data can be retrieved within this frequency range. Compensation values ​​whose sequence number is not a multiple of four directly use the previous compensation value whose sequence number is a multiple of four. This is beneficial for retrieving repetitive control data when the output frequency changes beyond the frequency range, thus preventing excessive deviations.

[0093] Combination Figure 8 As shown, in one embodiment of the present invention, when the current output frequency is in the fourth frequency range, the preset coefficient is 1 / 8, and the repetition control points include a first actual control point and a second actual control point. In step S30, the repetition control data for the current period includes the compensation amount of the first actual control point, the compensation amount of the second actual control point, and the compensation amount of the virtual control point. Correspondingly, step S30 generates the repetition control data for the current period in real time based on the number of repetition control points at the current moment, including:

[0094] Step S341: Determine the phase angle change step size for the current period based on the number of sampling points in the current period, and obtain the real-time phase angle based on the phase angle change step size;

[0095] Step S342: Take the product of the real-time phase angle and Nmax / (360×8), multiply it by 8 to get the first actual control point, and store the repetitive control compensation data calculated based on the real-time phase angle in the array at the position of the first actual control point;

[0096] Step S343: Take a multiple of 8 between the first actual control points as the second actual control point, and generate the compensation amount of the second actual control point by interpolation.

[0097] Step S344: taking the intermediate points between the first actual control point and the second actual control point as virtual control points, and taking the compensation amount of the previous first actual control point or the second actual control point as the compensation amount of the subsequent seven virtual control points.

[0098] Also taking the output frequency of the inverter power supply being 10-100Hz and the system sampling frequency fsam being 10000Hz as an example, if the current output frequency is in the fourth frequency interval, the number of repetitive control points N4 of the repetitive control data in one output voltage cycle is set to one eighth of the maximum number of control points Nmax (that is, one half of the number of repetitive control points N3 in the third frequency interval), that is, N4=1080 / 8=135, and the number of sampling points M4 in the current cycle is obtained by multiplying the number of repetitive control points N4 by a coefficient k (which can be set according to experimental data or experience, 0.5<k<1). For example, when k=0.8 (other parameters can also be selected), M4=k×N4=135×0.8=108. Correspondingly, the starting frequency of the third frequency interval is f3=fsam / M4=92.59Hz (accordingly, the second frequency interval is 46.3Hz to 92.59Hz, that is, when the output frequency is between 46.3Hz and 92.59Hz, the repetitive control number is generated according to steps S331 to S334, and when the output frequency is above 92.59Hz, the repetitive control number data is generated according to steps S341 to S344.

[0099] When the frequency of the output voltage is 92.59Hz, the phase angle variation step of the current cycle calculated in step S341 is 3.33, that is, the real-time phase angle θ of the m-th sampling point is θ=3.33×m. With reference to the accompanying drawings of the specification Figure 9 , the real-time phase angle at the starting moment is 0, and the real-time phase angles of the subsequent sampling points are 3.33°, 6.66°, 9.99°, etc. in sequence. Meanwhile, the serial number of the corresponding sampling point stored in the repetitive control data area of the current cycle is obtained by rounding (rounding off) 0.375 times of the real-time phase angle θ (since the number of repetitive control points N' at this time is 0.375 times of 360).

[0100] For example, when the real-time phase angle θ = 3.33°, its value is rounded down to 0.375, which equals 1. Multiplying this by 8 gives 8. In step S342, the repetitive control compensation data calculated based on the real-time phase angle θ = 3.33° is stored in the array at position 8. When the real-time phase angle θ = 6.66°, its value is rounded down to 0.375, which equals 3. Multiplying this by 8 gives 24. In step S342, the repetitive control compensation data calculated based on the real-time phase angle θ = 6.66° is stored in the array at position 24. The compensation value at position 16, which is a multiple of 8 between the compensation values ​​at positions 8 and 24, is used as the second actual control point. The compensation value is calculated using interpolation, for example, the average of the compensation values ​​at positions 8 and 24. Compensation values ​​in the repetitive control data whose positions are not multiples of 8 are used as virtual control points, directly using the compensation value of the previous multiple of 8. Figure 9 As shown. By using the above method, 1080 compensation values ​​can be obtained in sequence. These 1080 compensation values ​​are the repetitive control data for the current cycle, which serve as the basis for compensation in the next output voltage cycle.

[0101] Using the above method, all compensation values ​​stored in the repetitive control data can be retrieved within this frequency range. Compensation values ​​whose sequence number is not a multiple of eight directly use the previous compensation value whose sequence number is a multiple of eight. This is beneficial for retrieving repetitive control data when the output frequency changes beyond the frequency range, thus preventing excessive deviations.

[0102] In one embodiment of the present invention, step S20 above, which compensates for the amplitude of the current output voltage at each sampling point of the current cycle based on the repetition control data of the previous cycle, includes:

[0103] The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size.

[0104] At each real-time phase angle position, the sum of the p-th compensation value obtained from the repetitive control data of the previous cycle and the standard voltage at the real-time phase angle is used to control the current output voltage, where p is the integer product of the real-time phase angle and Nmax / 360.

[0105] The present invention also provides an inverter power supply, comprising: a digital controller and a memory communicatively connected to the digital controller; wherein the memory stores instructions executable by the digital controller, the instructions being executed by the digital controller to enable the digital controller to perform the wide frequency range repetitive control method as described above.

[0106] The inverter power supply in this embodiment is the same as the one described above. Figure 1-9The wide frequency range repetitive control method in the corresponding embodiments belongs to the same concept. The specific implementation process can be found in the corresponding method embodiments. The technical features in the method embodiments are also applicable to this device embodiment, and will not be repeated here.

[0107] The present invention also provides a computer-readable storage medium storing computer-executable instructions for causing a computer to perform the wide frequency range repetitive control method described above.

[0108] The computer-readable storage medium in this embodiment is the same as described above. Figure 1-9 The wide frequency range repetitive control method in the corresponding embodiments belongs to the same concept. The specific implementation process can be found in the corresponding method embodiments. The technical features in the method embodiments are also applicable to this device embodiment, and will not be repeated here.

[0109] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0110] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0111] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented 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 implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0112] In the embodiments provided in this application, it should be understood that the disclosed wide-frequency-range repetitive control method and inverter power supply can be implemented in other ways. For example, the inverter power supply embodiments described above are merely illustrative.

[0113] Furthermore, the functional units in the various embodiments of this application can be integrated into a single processor, or each unit can exist physically separately, or two or more units can be integrated into a single unit. The integrated units described above can be implemented in hardware or as software functional units.

[0114] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or interface switching device capable of carrying the computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0115] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A wide-frequency-range repetitive control method, characterized in that, Includes the following steps: The number of repeating control points at the current moment is obtained based on the frequency range in which the current output frequency is located. The number of repeating control points at the current moment is the product of the maximum number of control points and a preset coefficient, wherein the preset coefficient is less than or equal to 1. Based on the repetitive control data from the previous cycle, the amplitude of the current output voltage is compensated at each sampling point in the current cycle; The repeat control data for the current cycle is generated in real time based on the number of repeat control points at the current moment. The number of compensation amounts in the repeat control data of the previous cycle and the repeat control data of the current cycle is the same as the maximum number of control points. The maximum number of control points Nmax is an integer multiple of 360, and Tmax / Tsam≤Nmax≤Tmax / Tsam+360, where Tmax is the maximum period of the output voltage and Tsam is the sampling period; The number of repetitive control points in any frequency range is twice the number of repetitive control points in the adjacent high frequency range, and the number of repetitive control points corresponding to the current moment is not less than the quotient of the maximum period of the output voltage and the sampling period. The starting frequency f of the nth frequency interval satisfies: f = fsam / (Nmax × 2) -n+1 ×k), where fsam is the sampling period, k is a preset parameter and 0 < k < 1, and n is an integer greater than or equal to 2.

2. The wide frequency range repetitive control method according to claim 1, characterized in that, When the current output frequency is in the first frequency range, the preset coefficient is 1, the repetition control point includes the first actual control point and the second actual control point, and the repetition control data of the current cycle includes the compensation amount of the first actual control point and the second actual control point. The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes: The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size. The product of the real-time phase angle and Nmax / 360 is rounded down to the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array. The interval points between the first actual control points are used as the second actual control points, and the compensation amount of the second actual control points is generated by interpolation.

3. The wide frequency range repetitive control method according to claim 1, characterized in that, When the current output frequency is in the second frequency range, the preset coefficient is one-half, the repetitive control point includes the first actual control point and the second actual control point, and the repetitive control data of the current cycle includes the compensation amount of the first actual control point, the compensation amount of the second actual control point and the compensation amount of the virtual control point. The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes: The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size. The product of the real-time phase angle and Nmax / (360×2) is rounded down and multiplied by 2 to obtain the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array. The even number of intervals between the first actual control points is taken as the second actual control point, and the compensation amount of the second actual control point is generated by interpolation. The interval between the first actual control point and the second actual control point is used as a virtual control point, and the compensation amount of the previous first actual control point or the second actual control point is used as the compensation amount of the next virtual control point.

4. The wide frequency range repetitive control method according to claim 1, characterized in that, When the current output frequency is in the third frequency range, the preset coefficient is one-quarter, the repetitive control point includes the first actual control point and the second actual control point, and the repetitive control data of the current cycle includes the compensation amount of the first actual control point, the compensation amount of the second actual control point and the compensation amount of the virtual control point. The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes: The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size. The product of the real-time phase angle and Nmax / (360×4) is rounded down and multiplied by 4 to obtain the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array. The interval between the first actual control points is a multiple of 4, which is taken as the second actual control point, and the compensation amount of the second actual control point is generated by interpolation. The interval between the first and second actual control points is used as virtual control points, and the compensation amount of the previous first or second actual control point is used as the compensation amount of the last three virtual control points.

5. The wide frequency range repetitive control method according to claim 1, characterized in that, When the current output frequency is in the fourth frequency range, the preset coefficient is one-eighth, the repetitive control point includes the first actual control point and the second actual control point, and the repetitive control data of the current cycle includes the compensation amount of the first actual control point, the compensation amount of the second actual control point and the compensation amount of the virtual control point. The step of generating repeating control data for the current period in real time based on the number of repeating control points at the current moment includes: The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size. The product of the real-time phase angle and Nmax / (360×8) is rounded down and multiplied by 8 to obtain the first actual control point, and the repetitive control compensation data calculated based on the real-time phase angle is stored in the first actual control point position in the array. The interval between the first actual control points is a multiple of 8, which is taken as the second actual control point, and the compensation amount of the second actual control point is generated by interpolation. The interval between the first and second actual control points is used as virtual control points, and the compensation amount of the previous first or second actual control point is used as the compensation amount of the last seven virtual control points.

6. The wide frequency range repetitive control method according to any one of claims 1-5, characterized in that, The step of compensating the amplitude of the current output voltage at each sampling point in the current cycle based on the repetitive control data of the previous cycle includes: The phase angle change step size for the current period is determined based on the number of sampling points in the current period, and the real-time phase angle is obtained based on the phase angle change step size. At each real-time phase angle position, the sum of the p-th compensation value obtained from the repetitive control data of the previous cycle and the standard voltage at the real-time phase angle is used to control the current output voltage, where p is the integer product of the real-time phase angle and Nmax / 360.

7. An inverter power supply, characterized in that, include: A digital controller and a memory communicatively connected to the digital controller; wherein the memory stores instructions executable by the digital controller, the instructions being executed by the digital controller to enable the digital controller to perform the wide frequency range repetitive control method as described in any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions for causing a computer to perform the wide frequency range repetitive control method as described in any one of claims 1 to 6.

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