Three-phase current sampling crosstalk correction system and method for single motor

Abstract

The invention provides a three-phase current sampling crosstalk correction system and method of a single motor, the three-phase current sampling crosstalk correction system comprises a motor three-phase circuit and a single-chip microcomputer, the first phase of the motor three-phase circuit outputs a first phase current Iua to the single-chip microcomputer; the second phase outputs a second phase current Iva to the single-chip microcomputer; the third phase outputs a third phase current Iwa to the single-chip microcomputer; a compensation module is arranged in the single-chip microcomputer, a crosstalk compensation matrix is preset in the compensation module, the first phase current Iua, the second phase current Iva and the third phase current Iwa are constructed into a phase current matrix, the product of the phase current matrix and the crosstalk compensation matrix is calculated, and a real current matrix is obtained; and extracting a first real phase current Iub, a second real phase current Ivb and a third real phase current Iwb in the real current matrix and outputting the first real phase current Iub, the second real phase current Ivb and the third real phase current Iwb. After the technical scheme is adopted, the crosstalk compensation matrix is added into the algorithm, so that the interference of the two-phase sinusoidal current of the magnetic-core-free current sensor in the single motor on the sampling of the other-phase current can be corrected.

Description

Technical Field

[0001] The present invention relates to the field of motor control, and in particular to a system and method for correcting three-phase current sampling crosstalk of a single motor. Background Art

[0002] In a single-motor three-phase inverter bridge circuit, the physical properties of the materials used in the three-phase inverter bridge circuit result in crosstalk in the output currents of each phase. For example, when a permanent magnet synchronous motor is operating, the high-frequency sinusoidal current on the AC copper busbar causes crosstalk in the coreless current sensor. This affects the fundamental sinusoidal current being collected, affecting the physical properties of the coreless current sensor. This interferes with the currents of the other two phases, thus causing crosstalk. This causes the current values ​​collected by the microcontroller connected to the three-phase inverter bridge circuit to be crosstalk values, not true values, ultimately leading to misjudgment of the motor.

[0003] Among traditional solutions, the most common ones are to add shielding to the sensor or filtering circuits to the board. Regardless of which solution is used, it is costly and requires large amounts of computation, making it unsuitable for actual working conditions.

[0004] Therefore, a new type of single motor three-phase current sampling crosstalk correction system and method is needed to correct the interference of the two-phase sinusoidal current of the coreless current sensor in the single motor on the current sampling of another phase. Summary of the Invention

[0005] In order to overcome the above technical defects, the purpose of the present invention is to provide a three-phase current sampling crosstalk correction system and method for a single motor. By adding a crosstalk compensation matrix to the algorithm, the current sampling accuracy of the coreless current sensor is improved, thereby improving the accuracy of torque control.

[0006] The present invention discloses a three-phase current sampling crosstalk correction system for a single motor, comprising a three-phase circuit of the motor and a single chip microcomputer connected to the three-phase circuit of the motor. The three-phase circuit of the motor includes the first phase, the second phase, and the third phase; The first phase includes a first IGBT chip and a second IGBT chip connected to each other, and outputs a first phase current I ua To the microcontroller; The second phase includes a third IGBT chip and a fourth IGBT chip connected to each other, and outputs a second phase current I va To the microcontroller; The third phase includes a fifth IGBT chip and a sixth IGBT chip connected to each other, and outputs a third phase current I wa To the microcontroller; The single chip microcomputer is provided with a compensation module, which has a preset crosstalk compensation matrix. The compensation module converts the first phase current I ua , the second phase current Iva , the third phase current I wa Construct a phase current matrix, and calculate the product of the phase current matrix and the crosstalk compensation matrix to obtain the real current matrix, and extract the first real phase current I in the real current matrix ub , the second real phase current I vb , the third real phase current I wb And output.

[0007] Preferably, the phase current matrix is: ; The real current matrix is: ; The crosstalk compensation matrix is , so that the real current matrix is ​​calculated based on the following formula: .

[0008] Preferably, it also includes: A calibration device is connected to the three-phase circuit of the motor, wherein the calibration device comprises a DC source, a relay group and a calibration module; The relay group includes a first relay, a second relay, and a third relay, which are connected to the first phase, the second phase, and the third phase respectively. The DC source provides the first phase test current I to the first phase, the second phase, and the third phase respectively through the relay group. uc , Second phase test current I vc , the third phase test current I wc , so that the calibration module is based on the first phase test current I uc , Second phase test current I vc , the third phase test current I wc Calculate the inverse of the crosstalk compensation matrix .

[0009] Preferably, it is characterized in that the calibration module presets the inverse matrix for: ; The calibration module sets the first phase test current I output by the DC source uc , Second phase test current I vc , the third phase test current I wc Any two of them are 0A, and the remaining one is 100A; The calibration module collects the first phase current I from the microcontroller ua , the second phase current I va , the third phase current I wa The value of , and the inverse matrix is ​​calculated by the following formula Parameter a in ij : ; The calibration module inverts the inverse matrix A of which all parameters have been calibrated to obtain the crosstalk compensation matrix.

[0010] Preferably, it also includes: The host computer is connected to the calibration device, obtains the crosstalk compensation matrix, and converts the crosstalk compensation matrix into a floating point format and writes it into the microcontroller.

[0011] The present invention also discloses a method for correcting crosstalk of three-phase current sampling of a single motor, comprising the following steps: Construct a three-phase motor circuit and a single-chip microcomputer connected to the three-phase motor circuit, wherein the three-phase motor circuit includes a first phase, a second phase, and a third phase; the first phase includes a first IGBT chip and a second IGBT chip connected to each other, and outputs a first phase current I ua To the microcontroller; the second phase includes a third IGBT chip and a fourth IGBT chip connected to each other, and outputs the second phase current I va To the microcontroller; the third phase includes a fifth IGBT chip and a sixth IGBT chip connected to each other, and outputs a third phase current I wa To the microcontroller; The single chip microcomputer is provided with a compensation module, which has a preset crosstalk compensation matrix. The compensation module converts the first phase current I ua , the second phase current I va , the third phase current I wa Construct a phase current matrix, and calculate the product of the phase current matrix and the crosstalk compensation matrix to obtain the real current matrix, and extract the first real phase current I in the real current matrix ub , the second real phase current I vb , the third real phase current I wb And output.

[0012] Preferably, the phase current matrix is: ; The real current matrix is: ; The crosstalk compensation matrix is , so that the real current matrix is ​​calculated based on the following formula: .

[0013] Preferably, it also includes: Constructing a calibration device, connected to the three-phase circuit of the motor, wherein the calibration device comprises a DC source, a relay group, and a calibration module; The relay group includes a first relay, a second relay, and a third relay, which are connected to the first phase, the second phase, and the third phase respectively. The DC source provides the first phase test current I to the first phase, the second phase, and the third phase respectively through the relay group. uc , Second phase test current I vc , the third phase test current I wc, so that the calibration module is based on the first phase test current I uc , Second phase test current I vc , the third phase test current I wc Calculate the inverse of the crosstalk compensation matrix .

[0014] Preferably, the calibration module presets the inverse matrix for: ; The calibration module sets the first phase test current I output by the DC source uc , Second phase test current I vc , the third phase test current I wc Any two of them are 0A, and the remaining one is 100A; The calibration module collects the first phase current I from the microcontroller ua , the second phase current I va , the third phase current I wa The value of , and the inverse matrix is ​​calculated by the following formula Parameter a in ij : ; The calibration module inverts the inverse matrix A of which all parameters have been calibrated to obtain the crosstalk compensation matrix.

[0015] Preferably, it also includes: Build a host computer, connect it to the calibration equipment, obtain the crosstalk compensation matrix, convert the crosstalk compensation matrix into floating-point format and write it into the microcontroller.

[0016] Compared with the existing technology, the above technical solution has the following beneficial effects: By adding a crosstalk compensation matrix to the software algorithm, the interference of the two-phase sinusoidal current on the current sampling of the other phase can be corrected to improve the current sampling accuracy of the coreless current sensor, thereby improving the accuracy of torque control; The crosstalk coefficients between two phases of three-phase simultaneous outflow are simplified into a crosstalk matrix, reducing computing power requirements. It can take into account the crosstalk caused by currents of different amplitudes and frequencies, so as to improve the current sampling accuracy of the entire domain and thus improve the torque accuracy of motor control, and achieve it at a lower cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A topological diagram of a three-phase current sampling crosstalk correction system in accordance with a preferred embodiment of the present invention; Figure 2 This is a topological diagram of the host computer and the motor controller in the three-phase current sampling crosstalk correction system in accordance with a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0018] The advantages of the present invention are further described below with reference to the accompanying drawings and specific embodiments.

[0019] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all possible embodiments consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

[0020] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0021] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0022] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal communication between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0023] In the following description, the suffixes such as "module", "component" or "unit" used to represent elements are only used to facilitate the description of the present invention and have no specific meaning. Therefore, "module" and "component" can be used interchangeably.

[0024] See Figure 1 , shows a topological diagram of a three-phase current sampling crosstalk correction system in accordance with a preferred embodiment of the present invention. In this embodiment, the three-phase current sampling crosstalk correction system includes a three-phase circuit of a motor and a single-chip microcomputer connected to the three-phase circuit of the motor, characterized in that: The three-phase circuit of the motor includes a first phase, a second phase, and a third phase. The first phase includes a first IGBT chip and a second IGBT chip connected to each other; the second phase includes a third IGBT chip and a fourth IGBT chip connected to each other; and the third phase includes a fifth IGBT chip and a sixth IGBT chip connected to each other. Specifically, the first IGBT chip includes a first switch tube and a first diode connected in parallel with opposite current flows; the second IGBT chip includes a second switch tube and a second diode connected in parallel with opposite current flows. That is, when the first switch tube is turned on, the first diode is turned off; conversely, when the first switch tube is turned off, the first diode is turned on. The third IGBT chip includes a third switch tube and a third diode connected in parallel with opposite current flows; the fourth IGBT chip includes a fourth switch tube and a fourth diode connected in parallel with opposite current flows; the fifth IGBT chip includes a fifth switch tube and a fifth diode connected in parallel with opposite current flows; and the sixth IGBT chip includes a sixth switch tube and a sixth diode connected in parallel with opposite current flows. The first, second, and third phases respectively output the first phase current I ua , the second phase current I va , the third phase current I wa As mentioned above, the first phase current I ua , the second phase current I va , the third phase current I wa Affected by crosstalk, the above-mentioned phase current values ​​collected by the single-chip microcomputer are not the true values ​​of the phase currents of the three-phase inverter bridge. Therefore, a compensation module is provided in the single-chip microcomputer. The compensation module is preset with a crosstalk compensation matrix. The compensation module converts the first phase current I ua , the second phase current I va , the third phase current I wa Construct a phase current matrix, and calculate the product of the phase current matrix and the crosstalk compensation matrix to obtain the real current matrix, and extract the first real phase current I in the real current matrix ub , the second real phase current I vb , the third real phase current I wbThe crosstalk compensation matrix and calculation processes within the compensation module can be implemented through software algorithm programming. Due to the differences in physical properties, the crosstalk compensation matrix is ​​not universally applicable. Therefore, for each motor, a suitable crosstalk compensation matrix can be calibrated and stored, and matrix multiplication can be performed after completion. This requires minimal computing power and ultimately yields accurate true phase current values.

[0025] Further preferably, the phase current matrix and the real current matrix are respectively set as follows: the phase current matrix is: , the real current matrix is: ; The crosstalk compensation matrix is The above embodiment takes into account that the crosstalk phenomenon is the influence and deviation on the current values ​​of each phase of the real current. Therefore, its influence on the real current value can be summarized as the product of the real current value. For example, assuming that the influence of the crosstalk phenomenon on the real current value is the crosstalk matrix A, then in the absence of crosstalk, the matrixization of the current values ​​of each phase should be: , then after the crosstalk phenomenon occurs, the phase current matrix originally collected by the microcontroller = , if we can multiply the right side of the above matrix multiplication equation by , then the crosstalk phenomenon can be eliminated, that is, the real current matrix is ​​calculated based on the following formula: , and finally realize the first real phase current I after microcontroller compensation ub , the second real phase current I vb , the third real phase current I wb That is the actual value of each phase current I u , I v , I w .

[0026] In a preferred embodiment, For accurate calibration, see Figure 2 The three-phase current sampling crosstalk correction system also includes: a calibration device connected to the three-phase circuit of the motor, wherein the calibration device has a DC source, a relay group and a calibration module; the relay group includes a first relay, a second relay, and a third relay, which are respectively connected to the first phase, the second phase, and the third phase, and the DC source provides the first phase test current I to the first phase, the second phase, and the third phase respectively through the relay group. uc , Second phase test current I vc , the third phase test current I wc , the use of DC source makes the first phase test current I uc , Second phase test current I vc , the third phase test current I wcThe value is stable and does not deviate. Under the control of the first relay, the second relay, and the third relay (the relay group can be controlled by a host computer), the DC source is disconnected or connected to supply power to the motor controller. On each phase circuit side of the motor three-phase circuit of the motor controller, the calibration module collects the current of each phase (not the real value, but the crosstalk value after crosstalk, that is, the phase current matrix ), based on the phase current matrix and , and the relationship between the two: =A The inverse matrix of the crosstalk compensation matrix can be calculated .

[0027] Furthermore, to facilitate calibration, the calibration module presets the inverse matrix for: , the calibration module sets the first phase test current I output by the DC source uc , Second phase test current I vc , the third phase test current I wc Any two of them are 0A, and the remaining one is 100A; and the calibration module collects the first phase current I from the microcontroller ua , the second phase current I va , the third phase current I wa The value of , and the inverse matrix is ​​calculated by the following formula Parameter a in ij : For example, the calibration module sets I uc =0,I vc =100A, I wc =0, then after collecting the first phase current I ua , the second phase current I va , the third phase current I wa After the value of =1· + · + · = · ,but = / = / 100, = · + · + · = · ,but = / = / 100. Similarly, you can set I uc =0,I vc =0,I wc =100A, we get and Similarly, you can set the value of I uc =100A, I vc =0,I wc =0, we get and When all parameters are obtained, the calibration module inverts the inverse matrix A of all calibrated parameters to obtain the crosstalk compensation matrix .

[0028] It is understandable that in the above embodiment, for the convenience of calculation, 、 、 The default value is 1. In other implementations, 、 、 The default value is unknown, the first phase test current I uc , Second phase test current I vc , the third phase test current I wc The value of can also be any value, and the inverse matrix A can also be calculated through a set of parallel equations.

[0029] Furthermore, the three-phase current sampling crosstalk correction system also includes: a host computer, connected to the calibration device, after obtaining the crosstalk compensation matrix, converting the crosstalk compensation matrix into a floating point format and writing it into the single chip microcomputer. For example, 4 bytes represent a float type data, such as , the floating point format written to the microcontroller is In the above embodiments, the host computer sends instructions to the current source and the relay group through the UDS protocol or the DID protocol to control the output current and select which phase parameter to calibrate.

[0030] The present invention also discloses a method for correcting crosstalk of three-phase current sampling of a single motor, comprising the following steps: S100: Construct a three-phase motor circuit and a single-chip microcomputer connected to the three-phase motor circuit, wherein the three-phase motor circuit includes a first phase, a second phase, and a third phase; the first phase includes a first IGBT chip and a second IGBT chip connected to each other, and outputs a first phase current I ua To the microcontroller; the second phase includes a third IGBT chip and a fourth IGBT chip connected to each other, and outputs the second phase current I va To the microcontroller; the third phase includes a fifth IGBT chip and a sixth IGBT chip connected to each other, and outputs a third phase current I waTo the microcontroller; S200: A compensation module is provided in the single chip microcomputer. A crosstalk compensation matrix is ​​preset in the compensation module. The compensation module converts the first phase current I ua , the second phase current I va , the third phase current I wa Construct a phase current matrix, and calculate the product of the phase current matrix and the crosstalk compensation matrix to obtain the real current matrix, and extract the first real phase current I in the real current matrix ub , the second real phase current I vb , the third real phase current I wb And output.

[0031] Preferably, the phase current matrix is: ;The real current matrix is: ; The crosstalk compensation matrix is , so that the real current matrix is ​​calculated based on the following formula: .

[0032] Preferably, it also includes: constructing a calibration device, connected to the three-phase circuit of the motor, wherein the calibration device has a DC source, a relay group and a calibration module; the relay group includes a first relay, a second relay, and a third relay, which are respectively connected to the first phase, the second phase, and the third phase, and the DC source provides the first phase test current I to the first phase, the second phase, and the third phase respectively through the relay group. uc , Second phase test current I vc , the third phase test current I wc , so that the calibration module is based on the first phase test current I uc , Second phase test current I vc , the third phase test current I wc Calculate the inverse of the crosstalk compensation matrix .

[0033] Preferably, the calibration module presets the inverse matrix for: ; The calibration module sets the first phase test current I output by the DC source uc , Second phase test current I vc , the third phase test current I wc Any two of them are 0A, and the remaining one is 100A; and the calibration module collects the first phase current I from the microcontroller ua , the second phase current I va , the third phase current I wa The value of , and the inverse matrix is ​​calculated by the following formula Parameter a in ij : The calibration module inverts the inverse matrix A of all calibrated parameters to obtain the crosstalk compensation matrix.

[0034] Preferably, the method further includes: constructing a host computer, connecting it to the calibration device, obtaining the crosstalk compensation matrix, converting the crosstalk compensation matrix into a floating point format and writing it into the single chip microcomputer.

[0035] It should be noted that the embodiments of the present invention have better practicability and do not impose any form of limitation on the present invention. Any technician familiar with the field may use the technical content disclosed above to change or modify it into an equivalent effective embodiment. However, any modification or equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A three-phase current sampling crosstalk correction system for a single motor, comprising a three-phase circuit of the motor and a single-chip microcomputer connected to the three-phase circuit of the motor, characterized in that: The three-phase circuit of the motor includes a first phase, a second phase, and a third phase; The first phase includes a first IGBT chip and a second IGBT chip connected to each other, and outputs a first phase current I ua to the single chip microcomputer; The second phase includes a third IGBT chip and a fourth IGBT chip connected to each other, and outputs a second phase current I va to the single chip microcomputer; The third phase includes a fifth IGBT chip and a sixth IGBT chip connected to each other, and outputs a third phase current I wa to the single chip microcomputer; The single chip microcomputer is provided with a compensation module, which is preset with a crosstalk compensation matrix. The compensation module converts the first phase current I ua , the second phase current I va , the third phase current I wa Construct a phase current matrix, and calculate the product of the phase current matrix and the crosstalk compensation matrix to obtain a real current matrix, and extract the first real phase current I in the real current matrix ub , the second real phase current I vb , the third real phase current I wb And output.

2. The three-phase current sampling crosstalk correction system according to claim 1, characterized in that: The phase current matrix is: ; The real current matrix is: ; The crosstalk compensation matrix is , so that the real current matrix is ​​calculated based on the following formula: .

3. The three-phase current sampling crosstalk correction system according to claim 2, characterized in that: Also includes: A calibration device connected to the three-phase circuit of the motor, wherein the calibration device comprises a DC source, a relay group and a calibration module; The relay group includes a first relay, a second relay, and a third relay, which are respectively connected to the first phase, the second phase, and the third phase. The DC source provides a first phase test current I to the first phase, the second phase, and the third phase respectively through the relay group. uc , Second phase test current I vc , the third phase test current I wc , so that the calibration module is based on the first phase test current I uc , Second phase test current I vc , the third phase test current I wc Calculate the inverse of the crosstalk compensation matrix .

4. The three-phase current sampling crosstalk correction system according to claim 3, characterized in that: The calibration module presets the inverse matrix for: ; The calibration module sets the first phase test current I output by the DC source uc , Second phase test current I vc , the third phase test current I wc Any two of them are 0A, and the remaining one is 100A; The calibration module collects the first phase current I from the single chip microcomputer ua , the second phase current I va , the third phase current I wa The value of , and the inverse matrix is ​​calculated by the following formula Parameter a in ij : ； The calibration module inverts the inverse matrix A of which all parameters have been calibrated to obtain the crosstalk compensation matrix.

5. The three-phase current sampling crosstalk correction system according to claim 4, characterized in that: Also includes: The host computer is connected to the calibration device, obtains the crosstalk compensation matrix, and converts the crosstalk compensation matrix into a floating point format and writes it into the single chip microcomputer.

6. A method for correcting crosstalk in three-phase current sampling of a single motor, characterized by: The following steps are involved: Construct a three-phase motor circuit and a single-chip microcomputer connected to the three-phase motor circuit, wherein the three-phase motor circuit includes a first phase, a second phase, and a third phase; the first phase includes a first IGBT chip and a second IGBT chip connected to each other, and outputs a first phase current I ua To the single chip microcomputer; the second phase includes a third IGBT chip and a fourth IGBT chip connected to each other, and outputs a second phase current I va To the single chip microcomputer; the third phase includes a fifth IGBT chip and a sixth IGBT chip connected to each other, and outputs a third phase current I wa to the single chip microcomputer; The single chip microcomputer is provided with a compensation module, which is preset with a crosstalk compensation matrix. The compensation module converts the first phase current I ua , the second phase current I va , the third phase current I wa Construct a phase current matrix, and calculate the product of the phase current matrix and the crosstalk compensation matrix to obtain a real current matrix, and extract the first real phase current I in the real current matrix ub , the second real phase current I vb , the third real phase current I wb And output.

7. The three-phase current sampling crosstalk correction method according to claim 6, characterized in that: The phase current matrix is: ; The real current matrix is: ; The crosstalk compensation matrix is , so that the real current matrix is ​​calculated based on the following formula: .

8. The three-phase current sampling crosstalk correction method according to claim 7, characterized in that: Also includes: Constructing a calibration device, connected to the three-phase circuit of the motor, wherein the calibration device comprises a DC source, a relay group and a calibration module; The relay group includes a first relay, a second relay, and a third relay, which are respectively connected to the first phase, the second phase, and the third phase. The DC source provides a first phase test current I to the first phase, the second phase, and the third phase respectively through the relay group. uc , Second phase test current I vc , the third phase test current I wc , so that the calibration module is based on the first phase test current I uc , Second phase test current I vc , the third phase test current I wc Calculate the inverse of the crosstalk compensation matrix .

9. The three-phase current sampling crosstalk correction method according to claim 8, characterized in that: The calibration module presets the inverse matrix for: ; The calibration module sets the first phase test current I output by the DC source uc , Second phase test current I vc , the third phase test current I wc Any two of them are 0A, and the remaining one is 100A; The calibration module collects the first phase current I from the single chip microcomputer ua , the second phase current I va , the third phase current I wa The value of , and the inverse matrix is ​​calculated by the following formula Parameter a in ij : ； The calibration module inverts the inverse matrix A of which all parameters have been calibrated to obtain the crosstalk compensation matrix.

10. The three-phase current sampling crosstalk correction method according to claim 9, characterized in that: Also includes: A host computer is constructed and connected to the calibration device. After obtaining the crosstalk compensation matrix, the crosstalk compensation matrix is ​​converted into a floating point format and written into the single chip microcomputer.

Images