Secondary frequency modulation control method and device based on single-resistor sampling phase current reconstruction

Abstract

The invention discloses a secondary frequency modulation control method based on single-resistor sampling phase current reconstruction. The method comprises the following steps: acquiring a PWM signal of a to-be-sampled period; calculating a voltage vector and judging an area where the voltage vector is located; when the voltage vector is located at the edge of the sector, carrying out secondary modulation on the single-phase PWM signal, and respectively inserting a half of ADC current sampling window width into a rising edge and a falling edge of the PWM signal needing secondary frequency modulation; when the voltage vector is located in a low-voltage modulation area, carrying out secondary modulation on one phase of PWM signal in the previous period, respectively inserting a half ADC current sampling window width into a rising edge and a falling edge of the PWM signal needing secondary frequency modulation, and carrying out secondary modulation on the other phase of PWM signal in the adjacent next period; and a half of ADC current sampling window width is inserted into the rising edge and the falling edge of the PWM signal needing secondary frequency modulation respectively. According to the invention, the problem of single-resistor sampling phase current reconstruction is solved by using a method of carrying out secondary frequency modulation on an SPWM control signal by using an IPWM signal.

Description

Technical Field

[0001] The present invention specifically relates to a secondary frequency modulation control method and device based on single resistor sampling phase current reconstruction. Background Art

[0002] In the field vector control (FOC) of a brushless DC motor (BLDC) or a permanent magnet synchronous motor (PMSM), current sampling is a key step that directly affects the accuracy and efficiency of motor control. Current sampling is usually achieved through a Hall sensor or a shunt resistor, which mainly includes single resistor, dual resistor, and triple resistor.

[0003] The advantages of Hall sensor current sampling include non-contact measurement, ability to withstand high voltage, easy installation, low maintenance cost, fast response speed, etc. However, Hall sensors also have their limitations. For example, the Hall voltage signal is usually small and needs to be processed by an amplification circuit. In addition, the accuracy of the Hall sensor may be affected by factors such as temperature and core saturation. When designing a Hall sensor current sampling system, these factors need to be considered to ensure the accuracy and reliability of the measurement.

[0004] Dual-resistance sampling detects current by connecting resistors in series in two phases, and can sample when all lower bridge arms are turned on, which can reduce sampling errors. However, this method still has window time limitations, that is, the lower end of the bridge cannot be turned off before the ADC conversion is completed, which may affect the accuracy of sampling. Three-resistance sampling detects current by connecting resistors in series in all three phases of the three-phase inverter, and has higher sampling accuracy, but the cost is correspondingly higher.

[0005] Single resistor sampling is a low-cost method that detects current by connecting a resistor in series in any phase of the three-phase inverter of the motor. Since two samples need to be taken in one PWM cycle to reconstruct the three-phase current, the implementation of this method is relatively complicated. Phase shifting and simple deformation of the PWM control signal are often used to meet the sampling window width requirements. These methods can solve the sampling problem, but they are prone to generate harmonics, affecting the accuracy of current measurement. Summary of the invention

[0006] In order to solve the problem of difficulty in reconstructing phase current in non-observation area of ​​single resistor sampling, the present invention proposes a secondary frequency modulation control method and device based on single resistor sampling phase current reconstruction, which solves the problem of single resistor sampling phase current reconstruction by using IPWM signal to perform secondary frequency modulation on SPWM control signal.

[0007] According to one aspect of the present invention, a secondary frequency modulation control method based on single resistor sampling phase current reconstruction is provided, comprising: Get the periodic PWM signal to be sampled; Calculate the voltage vector and determine its area; When the voltage vector is at the edge of the sector, the single-phase PWM signal is modulated twice, and half of the ADC current sampling window width is inserted into the rising edge and falling edge of the PWM signal that needs secondary frequency modulation. When the voltage vector is in the low-voltage modulation area, one of the phase PWM signals is secondary modulated in the previous cycle, and half of the ADC current sampling window width is inserted into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation. In the next adjacent cycle, the other phase PWM signal is secondary modulated, and half of the ADC current sampling window width is inserted into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation.

[0008] As a further technical solution, when the voltage vector is located inside the sector, the phase current is sampled directly.

[0009] As a further technical solution, phase current reconstruction is performed based on the acquired phase current sampling data inside the sector, at the edge of the sector and in the low-voltage modulation area.

[0010] As a further technical solution, obtaining a periodic PWM signal to be sampled includes: obtaining a three-phase SPWM control signal of the period to be sampled, and the SPWM control signal is output in a center-aligned mode.

[0011] As a further technical solution, the method further includes: Calculate the ADC current sampling window width based on the ADC minimum sampling time and dead time; Configure the IPWM channel output as a secondary frequency modulation signal, determine the IPWM matching value according to the sampling window width, make the IPWM output pulse width length the same as the sampling window width, and the period the same as the SPWM control signal period; Configure the modulation enable of the SPWM channel and the IPWM channel to control whether any SPWM channel performs an AND operation with the IPWM signal to achieve secondary frequency modulation of the SPWM control signal.

[0012] As a further technical solution, the method further includes: When the SPWM modulation is enabled and the IPWM output is high, the SPWM output is in accordance with its original signal, and when the IPWM output is low, the SPWM output is low; When the SPWM modulation enable is turned off, the SPWM output is in accordance with its original signal.

[0013] According to one aspect of the present invention, there is provided a secondary frequency modulation control device based on single resistor sampling phase current reconstruction, comprising: An acquisition module, used for acquiring a periodic PWM signal to be sampled; A region determination module is used to calculate the voltage vector and determine the region where it is located; The sector edge processing module is used to perform secondary modulation on the single-phase PWM signal when the voltage vector is at the sector edge, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that needs secondary frequency modulation respectively; The low-voltage modulation area processing module is used to perform secondary modulation on one of the phase PWM signals in the previous cycle when the voltage vector is located in the low-voltage modulation area, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation, and perform secondary modulation on the other phase PWM signal in the next adjacent cycle, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation.

[0014] As a further technical solution, it also includes: a configuration module, which is used to calculate the ADC current sampling window width according to the ADC minimum sampling time and dead time; configure the IPWM channel output as a secondary frequency modulation signal, determine the IPWM matching value according to the sampling window width, so that the IPWM output pulse width length is the same as the sampling window width, and the period is the same as the SPWM control signal period; configure the SPWM channel and IPWM channel modulation enable to control whether any SPWM channel performs an AND operation with the IPWM signal to achieve secondary frequency modulation of the SPWM control signal.

[0015] According to one aspect of the present invention, there is provided a motor controller, comprising a memory and a processor, wherein the memory stores program instructions to be executed by the processor, and the processor calls the program instructions to execute the steps of the secondary frequency modulation control method based on single-resistance sampling phase current reconstruction.

[0016] According to one aspect of the present invention, there is provided a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the secondary frequency modulation control method based on single-resistance sampling phase current reconstruction are implemented.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses an IPWM signal to perform secondary modulation on the sampled SPWM signal, and adjusts the SPWM waveform at the sector edge and low-voltage modulation area to complete three-phase current reconstruction, which can solve the problem that single-resistance sampling phase current reconstruction cannot be sampled in the non-observation area.

[0018] 2. The present invention can realize the AND operation between any phase control signal in the three-phase SPWM and the IPWM signal by controlling the SPWM modulation enabling switch, and can realize the cycle-by-cycle adjustment of the three-phase SPWM signal.

[0019] 3. The present invention mainly implements control through chip hardware, with low system software overhead and no additional hardware is introduced to increase costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of a non-observation area for current sampling by a single resistor provided in an embodiment of the present invention.

[0021] Figure 2 A schematic diagram of a phase current reconstruction process provided by an embodiment of the present invention.

[0022] Figure 3 A schematic diagram of the sector edge SPWM output and secondary modulation and changing output waveform provided in an embodiment of the present invention.

[0023] Figure 4 A schematic diagram of the SPWM output in the low-voltage modulation area and the secondary modulation and changing output waveform provided in an embodiment of the present invention.

[0024] Figure 5 A schematic structural diagram of a secondary frequency modulation control device based on single resistor sampling phase current reconstruction provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In the prior art, Hall sensor current sampling, dual resistor and triple resistor current sampling are relatively expensive, and dual resistor and triple resistor sampling also have sampling window limitations. In single resistor sampling applications, sufficient sampling time cannot be reserved at the edge of the vector voltage sector and the low-voltage modulation area. We call these areas the current reconstruction non-observation area. In order to solve the problem of difficulty in sampling phase current in the current reconstruction non-observation area with single resistor sampling, most applications use phase shifting or simple deformation of the PWM control signal to generate an ADC sampling window that meets the requirements. Both can solve the sampling problem in the non-observation area to a certain extent, but phase shifting will produce harmonics, and the reconstructed current waveform distortion rate is relatively high. Simple waveform transformation of PWM will cause output voltage errors, which will also cause current distortion.

[0026] To this end, the present invention proposes a method for performing secondary frequency modulation on an SPWM control signal using an IPWM signal to solve the problem of phase current reconstruction in a non-observation area using a single resistor sampling.

[0027] It should be noted that: The SPWM (Shared Plused Width Modulation) mentioned in the specification of the present invention is an 8-channel output, the output is controlled by a counter, and the multi-channel output has the same cycle, but the duty cycle can be adjusted independently. IPWM (Independent Plused Width Modulation) is a 4-channel output, each channel is controlled by a counter, and the cycle and duty cycle of each channel can be controlled independently.

[0028] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] An embodiment of the present invention provides a secondary frequency modulation control method based on single-resistance sampling phase current reconstruction. The method is aimed at the application of single-resistance sampling current reconstruction, and solves the problem of difficulty in sampling bus current in sector transition area and low-voltage modulation area by secondary modulating SPWM control signal through IPWM signal.

[0030] The secondary frequency modulation control method based on single-resistance sampling phase current reconstruction provided by the embodiment of the present invention, first, for the voltage vector falling into different regions, different phase current sampling modes are set. Then, the three-phase SPWM control signal of the sampling period is obtained, and the region to which its voltage vector belongs is determined. If the voltage vector is inside the sector, the phase current sampling is directly performed. If not, it is further determined whether the voltage vector is located at the edge of the sector or the low-voltage modulation area. Then, if the voltage vector is located at the edge of the sector, the single-phase PWM signal is secondary modulated, and then the rising edge and falling edge of the PWM signal that requires secondary frequency modulation are respectively inserted with half of the ADC current sampling window width; if the voltage vector is located in the low-voltage modulation area, one of the phase PWM signals is secondary modulated in the previous cycle, and then the rising edge and falling edge of the PWM signal that requires secondary frequency modulation are respectively inserted with half of the ADC current sampling window width, and then another phase PWM signal is secondary modulated in the next adjacent cycle, and then the rising edge and falling edge of the PWM signal that requires secondary frequency modulation are respectively inserted with half of the ADC current sampling window width. Finally, the phase current is reconstructed according to the phase current sampling data.

[0031] The embodiment of the present invention calculates the ADC current sampling window width Tmin based on the ADC minimum sampling time and dead time. The IPWM channel output is configured as a secondary frequency modulation signal, and the IPWM matching value is determined according to the sampling window length to ensure that the IPWM output pulse width length is the same as Tmin, and the period is the same as the SPWM control signal period. The SPWM channel and the IPWM channel modulation enable are set to control whether any SPWM channel performs an AND operation with the IPWM signal, so as to achieve the purpose of performing secondary frequency modulation on the SPWM control signal.

[0032] Furthermore, when the SPWM modulation enable is turned on and the IPWM output is high, the SPWM output is according to its original signal, when the IPWM output is low, the SPWM output is low, and when the SPWM modulation enable is turned off, the SPWM output is according to its original signal. Based on this secondary frequency modulation method, any one phase of the three-phase SPWM control signal can be flexibly controlled.

[0033] The embodiment of the present invention calculates the reference voltage according to the output voltage, and determines the output voltage sector by the reference voltage calculation. When the vector voltage is within the sector, the two-phase SPWM edge difference is greater than the ADC current sampling window width Tmin, the phase current is sampled at the trigger point, and the output phase current is calculated based on the sampled current and the output voltage sector.

[0034] When the vector voltage is at the edge of the sector, the difference between the two-phase SPWM edges is less than the ADC current sampling window width Tmin. In this case, only the A-phase current can be sampled at the trigger point. In order to meet the requirements of the ADC current sampling window width, it is necessary to output a low level at the center of one of the two-phase signals with close edges, and the low level width is greater than or equal to Tmin. The specific operation is to enable the corresponding SPWM signal modulation function, so that the SPWM signal can be ANDed with the IPWM signal to obtain the target signal. After secondary frequency modulation, the sampling SPWM waveform center point can generate a low pulse width of the sampling window width, and the phase current can be sampled at this window to the B-phase or C-phase current. In addition, it is necessary to modify the matching value of the SPWM control signal of the sampling period to be sampled, insert a target insertion vector with a width of Tmin / 2 before and after the SPWM signal that needs secondary frequency modulation, and compensate the SPWM signal after secondary frequency modulation so that the SPWM output voltage vector is consistent with the length of the original SPWM output voltage vector.

[0035] When the vector voltage is in the low-voltage modulation area, the edge gaps of the three-phase SPWM are all smaller than the ADC current sampling window width Tmin, and the phase current cannot be sampled. In this case, it is necessary to perform secondary frequency modulation on the two-phase SPWM signals in two adjacent cycles to obtain the sampling window. In the first cycle, the secondary modulation function of the B-phase SPWM is enabled, and the secondary frequency modulation function of the A-phase and C-phase SPWM signals is turned off. In this way, only the B-phase signal of the SPWM is ANDed with the IPWM signal, thereby obtaining a sampling window of sufficient width. In addition, the matching value of the B-phase SPWM is modified, and a target insertion vector with a width of Tmin / 2 is inserted before and after the SPWM output signal, so that the SPWM output voltage vector is consistent with the original SPWM output voltage vector length, and the B-phase current can be obtained by sampling at the trigger point. In the next cycle, only the secondary frequency modulation function of the C-phase SPWM is enabled, the secondary frequency modulation function of the A-phase and B-phase is turned off, and the target insertion vector with a width of Tmin / 2 is inserted before and after the output signal. The C-phase current can be obtained by sampling at the trigger point.

[0036] Figure 1 The non-observation area of ​​single resistor sampling current reconstruction is given, including the sector edge and low-voltage modulation area. The non-observation area cannot meet the sampling window width requirement because the SPWM edge is close.

[0037] Figure 2 A phase current reconstruction flow chart is given. According to the sampled SPWM output, the SPWM output is secondary modulated by IPWM, and then the waveform is further transformed to meet the requirements of the current sampling window width, thereby realizing full-domain current reconstruction.

[0038] like Figure 2 As shown, the secondary frequency modulation control method based on single resistor sampling phase current reconstruction provided by the embodiment of the present invention includes the following steps: Step 1, obtain the periodic SPWM signal to be sampled. The SPWM signal is a centrally symmetrical waveform. During the counter counting up process, when the counter value reaches the matching value, it outputs a high level. During the counter counting down process, when the counter value reaches the matching value, it outputs a low level. When the matching value of the upward counting is the same as the matching value of the downward counting, the SPWM outputs a centrally symmetrical waveform. Similarly, the IPWM outputs a centrally symmetrical waveform. When the IPWM counter counts to the first matching value, it outputs a low level, and when it counts to the second matching value, it outputs a high level. The low pulse width of the IPWM output waveform is the minimum value of the sampling width Tmin, and the IPWM period is consistent with the SPWM period.

[0039] Step 2: Calculate the sector where the voltage vector is located based on the voltage value. When the voltage vector is inside the sector, the width between the edges of the three-phase SPWM signal meets the ADC sampling requirements. The currents of two phases can be sampled normally within one SPWM cycle, and then the current of the other phase is calculated based on the phase current relationship. The three-phase current reconstruction is completed based on the sector where the voltage vector is located.

[0040] Step 3: When the voltage vector is not inside the sector, determine whether the voltage vector is located at the edge of the sector or in the low voltage modulation area.

[0041] When the voltage vector is located at the edge of the sector, that is, the width between the edges of two phases of the three-phase SPWM signal is smaller than the current sampling width, such as Figure 3 The Sb and Sc signals in the SPWM can only sample the A-phase current at sampling point 1, and the three-phase current reconstruction cannot be completed. In this case, the Sc modulation function is enabled at the beginning of the SPWM cycle, and the Sc signal is secondary modulated using the IPWM (Im) signal. The Sc signal output changes to a low level in the IPWM output low level interval. At this time, the minimum sampling window can be met, and the ADC is triggered at sampling point 2 to sample the C-phase current. Since the secondary modulation will change the duty cycle of the SPWM signal, the matching value of the SPWM up-count and down-count is reduced at this time, so that the SPWM rising edge width and falling edge width are extended by Tmin / 2, which can ensure that the SPWM duty cycle remains unchanged, does not cause the voltage vector to decrease, and avoids current distortion. In this way, the A-phase and C-phase currents can be sampled, and the three-phase current reconstruction can be completed.

[0042] When the voltage vector is in the low voltage modulation area, that is, the width between the three-phase signal edges in the three-phase SPWM signal edge is less than the current sampling width Tmin, such as Figure 4In this case, the phase current cannot be sampled, and thus the three-phase current reconstruction cannot be completed. To solve this problem, in the first cycle of two consecutive SPWM cycles, the Sb modulation function is enabled at the beginning of the cycle, and the other two-phase modulation functions are turned off. The Sb signal is modulated twice using the IPWM (Im) signal. The Sb signal is output to a low level in the low-level interval of the IPWM output. At this time, the minimum ADC sampling window can be met. The ADC is triggered to sample the B-phase current at sampling point 3. To avoid vector voltage loss, the B-phase SPWM matching value is modified so that the SPWM rising edge width and falling edge width are extended by Tmin / 2. Similarly, in the next adjacent SPWM cycle, the Sc modulation function is enabled at the beginning of the cycle, and the other two-phase modulation functions are turned off. The Sc signal is modulated twice using the IPWM (Im) signal. The Sc signal is output to a low level in the low-level interval of the IPWM output. At this time, the minimum ADC sampling window can be met. The ADC is triggered to sample the C-phase current at sampling point 4. The C-phase SPWM matching value is modified so that the SPWM rising edge width and falling edge width are extended by Tmin / 2 to avoid voltage vector reduction. In this way, the two-phase currents Ib and Ic can be sampled, thereby completing the three-phase current reconstruction.

[0043] Step 4: Reconstruct the phase current according to the phase current sampling result.

[0044] Based on the same inventive concept as the above method embodiment, the embodiment of the present invention also provides a secondary frequency modulation control device based on single resistor sampling phase current reconstruction, such as Figure 5 As shown, including: The acquisition module is used to acquire the three-phase SPWM control signal of the period to be sampled, and the SPWM control signal is output in a center-aligned mode.

[0045] The region judgment module is used to calculate the voltage vector and determine the region it is in. This step calculates the reference voltage based on the output voltage, and determines the output voltage sector based on the reference voltage calculation. When the vector voltage is within the sector, the difference between the two-phase SPWM edges is greater than the ADC current sampling window width Tmin, the phase current is sampled at the trigger point, and the output phase current is calculated based on the sampled current and the output voltage sector.

[0046] The sector edge processing module is used to perform secondary modulation on the single-phase PWM signal when the voltage vector is located at the sector edge, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation.

[0047] The low-voltage modulation area processing module is used to perform secondary modulation on one of the phase PWM signals in the previous cycle when the voltage vector is located in the low-voltage modulation area, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation, and perform secondary modulation on the other phase PWM signal in the next adjacent cycle, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation.

[0048] The above-mentioned device embodiment uses an IPWM signal to perform secondary modulation on the sampled SPWM signal, and adjusts the SPWM waveform at the sector edge and the low-voltage modulation area to complete the three-phase current reconstruction, thereby solving the problem that the single-resistance sampling phase current reconstruction cannot be sampled in the non-observation area. The above-mentioned device is controlled by the hardware of the chip, with low software overhead and no additional hardware cost.

[0049] The embodiment of the present invention also includes: a configuration module, which is used to calculate the ADC current sampling window width according to the ADC minimum sampling time and the dead time; configure the IPWM channel output as a secondary frequency modulation signal, determine the IPWM matching value according to the sampling window width, so that the IPWM output pulse width length is the same as the sampling window width, and the period is the same as the SPWM control signal period; configure the SPWM channel and the IPWM channel modulation enable, which is used to control whether any SPWM channel performs an AND operation with the IPWM signal to realize the secondary frequency modulation of the SPWM control signal.

[0050] An embodiment of the present invention also provides a motor controller, including a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the secondary frequency modulation control method based on single-resistance sampling phase current reconstruction.

[0051] When the motor controller provided by the above embodiment is used to control the field vector of a brushless DC motor or a permanent magnet synchronous motor, the single-resistance sampling phase current reconstruction is achieved by performing secondary frequency modulation on the SPWM control signal using the IPWM signal, which can improve the accuracy of current sampling and thereby improve the accuracy and efficiency of motor control.

[0052] An embodiment of the present invention further provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the secondary frequency modulation control method based on single-resistance sampling phase current reconstruction.

[0053] It should be noted that the above-mentioned multiple embodiments are only examples, and the technical solutions of various embodiments can be combined, all of which are within the protection scope of the present invention.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A secondary frequency modulation control method based on single resistor sampling phase current reconstruction, characterized in that: include: Get the periodic PWM signal to be sampled; Calculate the voltage vector and determine its area; When the voltage vector is at the edge of the sector, the single-phase PWM signal is modulated twice, and half of the ADC current sampling window width is inserted into the rising edge and falling edge of the PWM signal that needs secondary frequency modulation. When the voltage vector is in the low-voltage modulation area, one of the phase PWM signals is secondary modulated in the previous cycle, and half of the ADC current sampling window width is inserted into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation. In the next adjacent cycle, the other phase PWM signal is secondary modulated, and half of the ADC current sampling window width is inserted into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation.

2. According to claim 1, the secondary frequency modulation control method based on single resistor sampling phase current reconstruction is characterized in that: When the voltage vector is inside the sector, the phase current is sampled directly.

3. The secondary frequency modulation control method based on single resistor sampling phase current reconstruction according to claim 2 is characterized in that: The phase current is reconstructed based on the acquired phase current sampling data inside the sector, at the sector edge and in the low-voltage modulation area.

4. The secondary frequency modulation control method based on single resistor sampling phase current reconstruction according to claim 1 is characterized in that: Acquiring a periodic PWM signal to be sampled includes: acquiring a three-phase SPWM control signal of the period to be sampled, wherein the SPWM control signal is output in a center-aligned mode.

5. The secondary frequency modulation control method based on single resistor sampling phase current reconstruction according to claim 1 is characterized in that: The method further comprises: Calculate the ADC current sampling window width based on the ADC minimum sampling time and dead time; Configure the IPWM channel output as a secondary frequency modulation signal, determine the IPWM matching value according to the sampling window width, make the IPWM output pulse width length the same as the sampling window width, and the period the same as the SPWM control signal period; Configure the modulation enable of the SPWM channel and the IPWM channel to control whether any SPWM channel performs an AND operation with the IPWM signal to achieve secondary frequency modulation of the SPWM control signal.

6. The secondary frequency modulation control method based on single resistor sampling phase current reconstruction according to claim 5 is characterized in that: The method further comprises: When the SPWM modulation is enabled and the IPWM output is high, the SPWM output is in accordance with its original signal, and when the IPWM output is low, the SPWM output is low; When the SPWM modulation enable is turned off, the SPWM output is in accordance with its original signal.

7. A secondary frequency modulation control device based on single resistor sampling phase current reconstruction, characterized in that: include: An acquisition module, used for acquiring a periodic PWM signal to be sampled; A region determination module is used to calculate the voltage vector and determine the region where it is located; The sector edge processing module is used to perform secondary modulation on the single-phase PWM signal when the voltage vector is at the sector edge, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that needs secondary frequency modulation respectively; The low-voltage modulation area processing module is used to perform secondary modulation on one of the phase PWM signals in the previous cycle when the voltage vector is located in the low-voltage modulation area, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation, and perform secondary modulation on the other phase PWM signal in the next adjacent cycle, and insert half of the ADC current sampling window width into the rising edge and falling edge of the PWM signal that requires secondary frequency modulation.

8. The secondary frequency modulation control device based on single resistor sampling phase current reconstruction according to claim 7, characterized in that: Also includes: A configuration module is used to calculate the ADC current sampling window width according to the ADC minimum sampling time and dead time; Configure the IPWM channel output as a secondary frequency modulation signal, determine the IPWM matching value according to the sampling window width, so that the IPWM output pulse width length is the same as the sampling window width, and the period is the same as the SPWM control signal period; configure the SPWM channel and IPWM channel modulation enable to control whether any SPWM channel performs an AND operation with the IPWM signal to achieve secondary frequency modulation of the SPWM control signal.

9. A motor controller, characterized in that: It comprises a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the secondary frequency modulation control method based on single-resistance sampling phase current reconstruction as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the secondary frequency modulation control method based on single-resistance sampling phase current reconstruction according to any one of claims 1 to 6 are implemented.

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