Reluctance motor sensorless control method and system based on high-frequency voltage correction

Abstract

The invention provides a reluctance motor sensorless control method and system based on high-frequency voltage correction, and the method comprises the steps: carrying out the sampling of three-phase current outputted by a synchronous reluctance motor, and obtaining three-phase current data; converting the three-phase current to obtain alpha-beta-axis current; processing the alpha-beta axis current and the lagged half-cycle signal thereof to obtain high-frequency alpha-beta axis current; converting the alpha-beta-axis current to obtain a dq-axis current, and processing the dq-axis current and a signal of lagging half cycle of the dq-axis current to obtain a fundamental frequency dq-axis current; subtracting the lagging current from the high-frequency alpha-beta-axis current to obtain a current variable quantity; processing the obtained current variable quantity through a phase-locked loop structure to obtain an estimated rotating speed and an estimated rotor position; and processing the estimated rotating speed and the estimated rotor position to obtain a switching signal, wherein the switching signal is used for controlling the synchronous reluctance motor.

Description

Technical Field

[0001] The present invention belongs to the technical field of synchronous reluctance motor control, and in particular relates to a sensorless control method and system for a reluctance motor based on high-frequency voltage correction. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Synchronous reluctance motors are considered to be an ideal choice to replace induction motors in various industrial fields due to their simple manufacturing process, high operating efficiency and low production and maintenance costs. In the past, synchronous reluctance motor control required mechanical sensors, which were prone to failure under some harsh conditions such as high temperature, vibration, and dust. In large-scale production, the presence of sensors will significantly increase the overall cost of the system and have a negative impact on the competitiveness of the product. At the same time, regular inspection and maintenance are also required. Due to wear and aging of the sensors, they may also need to be replaced, increasing the cost and complexity of maintenance. The demand for reliable and high-precision sensorless control of synchronous reluctance motors is imminent.

[0004] Commonly used sensorless control methods can be divided into two categories, those suitable for zero and low speed and those suitable for medium and high speed. The zero and low speed methods include high-frequency square wave injection, high-frequency sine wave injection and high-frequency pulse signal injection. When high-frequency signal injection is used, additional torque fluctuations and noise will be introduced. When a single-axis high-frequency square wave voltage signal is injected for sensorless control, the injected high-frequency square wave voltage signal is usually used directly as the high-frequency voltage value to obtain the αβ high-frequency current equation, which contains the rotor position error θ err Information, through vector cross product, the traditional phase-locked loop structure is derived. However, due to the coupling effect of the mathematical model of the synchronous magnetic motor, if a high-frequency square wave voltage signal is injected into the d-axis, the q-axis will respond to the high-frequency voltage signal; if a high-frequency square wave voltage signal is injected into the q-axis, the d-axis will respond to the high-frequency voltage signal. Therefore, the injected high-frequency square wave voltage signal is not a high-frequency voltage value, resulting in inaccurate αβ high-frequency current equations, resulting in inaccurate derived phase-locked loop structure, and there must be errors between the estimated rotor position and the actual rotor position, which affects the control accuracy of the motor sensorless control, manifested as torque fluctuations and speed fluctuations. Summary of the invention

[0005] In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a sensorless control method for a reluctance motor based on high-frequency voltage correction, which reduces the rotor position estimation error by improving the phase-locked loop structure.

[0006] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0007] In a first aspect, a sensorless control method for a reluctance motor based on high frequency voltage correction is disclosed, comprising:

[0008] Sampling the three-phase current output by the synchronous reluctance motor to obtain three-phase current data;

[0009] The three-phase current is transformed to obtain the αβ axis current;

[0010] The high-frequency αβ axis current is obtained by processing the αβ axis current and its lagging half-cycle signal;

[0011] The αβ axis current is transformed to obtain the dq axis current, and the current and its lagging half cycle signal are processed to obtain the fundamental frequency dq axis current;

[0012] Subtract the high-frequency αβ axis current from the hysteresis current to obtain the current variation;

[0013] The obtained current variation is processed through a phase-locked loop structure to obtain an estimated speed and an estimated rotor position;

[0014] The estimated speed and the estimated rotor position are processed to obtain a switching signal, which is used to control the synchronous reluctance motor.

[0015] As a further technical solution, the estimated speed and the estimated rotor position are processed to obtain a switch signal, specifically:

[0016] The estimated speed is subtracted from the reference speed, and the dq axis current distribution is determined according to the maximum torque current ratio control. The dq axis voltage is obtained through the current loop, and the signal is processed to obtain a switching signal for processing the DC voltage source, which is used to control the synchronous reluctance motor.

[0017] As a further technical solution, the obtained current variation is processed through a phase-locked loop structure to obtain an estimated speed and an estimated rotor position. The specific process is as follows:

[0018] The current change Δi in the αβ axis αh , Δi βh contains the rotor position information, and the change in the αβ axis current is multiplied by the sign function of the corresponding injected high-frequency voltage to obtain Δi αh Sign(u dh ), Δi βh Sign(u dh )(or Δi αh Sign(u qh ), Δi βh Sign(u qh )), and obtain the rotor position information θ e The trigonometric functions of .

[0019] Since the improved phase-locked loop structure takes into account the effect of the synchronous reluctance motor coupling effect, the product of the αβ axis current change and the sign function of the corresponding high-frequency voltage is a rotor position information θ e and compensation angle The trigonometric functions of the sum.

[0020] So Δi αh Sign(u dh ), Δi βh Sign(u dh )(or Δi αh Sign(u qh ), Δi βh Sign(u qh )) and the sum of the estimated rotor position information and the compensation angle construct a trigonometric function, and perform vector cross multiplication to obtain the rotor position error θ err The rotor position error is adjusted by PI to obtain the estimated speed, and the rotor position error is used to obtain the estimated rotor position.

[0021] The estimated rotor position is added with the compensation angle Constructing trigonometric functions and Δi αh Sign(u dh ), Δi βh Sign(u dh )(or Δi αh Sign(u qh ), Δi βh Sign(u qh ))Perform vector cross product to form a closed loop.

[0022] In a second aspect, a sensorless control system for a reluctance motor based on high frequency voltage correction is disclosed, comprising:

[0023] The three-phase current data sampling module is configured to: sample the three-phase current output by the synchronous reluctance motor to obtain three-phase current data;

[0024] The three-phase current data processing module is configured to: transform the three-phase current to obtain the αβ axis current;

[0025] The high-frequency αβ axis current is obtained by processing the αβ axis current and its lagging half-cycle signal;

[0026] The αβ axis current is transformed to obtain the dq axis current, and the current and its lagging half cycle signal are processed to obtain the fundamental frequency dq axis current;

[0027] Subtract the high-frequency αβ axis current from the hysteresis current to obtain the current variation;

[0028] The speed and rotor position estimation module is configured to: process the obtained current variation through a phase-locked loop structure to obtain an estimated speed and an estimated rotor position;

[0029] The control module is configured to: process the estimated rotation speed and the estimated rotor position to obtain a switching signal, wherein the switching signal is used to control the synchronous reluctance motor.

[0030] One or more of the above technical solutions have the following beneficial effects:

[0031] The technical solution of the present invention discloses a sensorless control method for a synchronous reluctance motor based on an improved phase-locked loop structure, comprising: when a high-frequency square wave is injected into the d-axis or q-axis alone, the relationship between the current change value of the αβ axis system and the rotor position is obtained, the phase-locked loop structure is determined to obtain the rotor position error, the estimated speed is obtained through PI adjustment, and the rotor position is obtained by integrating the estimated speed; due to the influence of the coupling effect, the voltage value when a high-frequency square wave voltage signal is injected into the d-axis or q-axis alone is corrected to obtain the corrected current change value and the rotor position relationship, the rotor position error is obtained through the improved phase-locked loop structure, the estimated speed is obtained through PI adjustment, and the rotor position is obtained by integrating the estimated speed, thereby realizing sensorless control.

[0032] The technical solution of the present invention is based on a sensorless control method for a synchronous reluctance motor with an improved phase-locked loop structure, which reduces the error in rotor position estimation by correcting a high-frequency voltage value and improving the phase-locked loop structure.

[0033] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0035] Figure 1 It is a flow chart of sensorless control of synchronous reluctance motor with d-axis high frequency square wave injection according to the present invention;

[0036] Figure 2 The d-axis high frequency injection improved phase-locked loop structure of the present invention;

[0037] Figure 3 It is the difference between the actual rotor position and the estimated rotor position when the d-axis high-frequency square wave is injected into the sensorless control. The operating condition is set to a speed of 500r / min and an amplitude of 2Nm. The red solid line is the result obtained by the traditional phase-locked loop, and the blue solid line is the result obtained by the improved phase-locked loop.

[0038] Figure 4is a flow chart of sensorless control of synchronous reluctance motor with q-axis high frequency square wave injection according to the present invention;

[0039] Figure 5 The q-axis high frequency injection improved phase-locked loop structure of the present invention;

[0040] Figure 6 It is the difference between the actual rotor position and the estimated rotor position when the q-axis high-frequency square wave is injected into the sensorless control. The operating condition is set to a speed of 500r / min and an amplitude of 2Nm. The red solid line is the result obtained by the traditional phase-locked loop, and the blue solid line is the result obtained by the improved phase-locked loop. DETAILED DESCRIPTION

[0041] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0042] It should be noted that the terms used herein are for describing specific embodiments only and are not intended to be limiting of exemplary embodiments according to the present invention.

[0043] In the absence of conflict, the embodiments of the present invention and the features of the embodiments may be combined with each other.

[0044] Overall concept:

[0045] Establish the mathematical model of synchronous reluctance motor in rotating coordinate system;

[0046] A high-frequency square wave signal is injected into the d-axis or q-axis of the estimated rotating coordinate system, and the three-phase current of the synchronous reluctance motor is sampled. The response current in the rotating coordinate system is determined according to the Clarke transformation, and the fundamental frequency AC-DC axis current and the AC-DC axis high-frequency response current are determined by using the delayed half-cycle response current.

[0047] Based on the relationship between the high-frequency current and the rotor position, a phase-locked loop is used to estimate the rotor position, and an estimated rotor position and an estimated speed are determined;

[0048] The high-frequency voltage value equation of the single-axis injected high-frequency square wave voltage is corrected, the corresponding high-frequency current and rotor position relationship is determined, and the rotor position is estimated using an improved phase-locked loop to achieve sensorless control. The present invention obtains a new high-frequency current and rotor position relationship based on the corrected high-frequency voltage equation, determines an improved phase-locked loop, and reduces the rotor position estimation error in sensorless control.

[0049] Embodiment 1

[0050] This embodiment discloses a sensorless control method for a reluctance motor based on high-frequency voltage correction, comprising:

[0051] Step S1: Sampling the three-phase current output by the synchronous reluctance motor to obtain a visible three-phase current i a 、i b 、i c The three-phase current is transformed by CLARK to obtain the αβ axis current i α 、i β , discretize it and process it with the signal of the delayed half cycle to obtain the high-frequency αβ axis current i αh 、i βh :

[0052]

[0053] In the formula, i αh 、i βh is the high frequency αβ axis current, i α (k), i β (k) is the discrete signal of αβ axis current.

[0054] The high frequency αβ axis current i αh 、i βh Formula (1) is discretized, and the signal is subtracted from the signal of its half-cycle lag to obtain the high-frequency αβ axis current change value Δi αh , Δi βh :

[0055]

[0056] In the formula, Δi αh , Δi βh is the high frequency αβ axis current change value, i αh (k), i βh (k) is the discrete signal of αβ axis current.

[0057] In the high frequency αβ axis current change signal Δi αh , Δi βh It contains the rotor position information, and the specific principle is as follows:

[0058] Establish the mathematical model of synchronous reluctance motor.

[0059]

[0060] In the formula, u d 、u q is the dq axis voltage; i d 、i q is the dq axis current; L d , L q is the direct-axis and quadrature-axis inductance; R is the resistance; ω e is the electrical angular velocity.

[0061] Inject high-frequency voltage into the direct or quadrature axis, based on the mathematical model of synchronous reluctance motor, the coupling part ω e L dh i dh 、-ω e L qh i qh And the resistance voltage drop part Ri dh 、Ri qh The high-frequency voltage equation of the synchronous reluctance motor can be simplified to:

[0062]

[0063] In the formula, u dh 、u qh is the high frequency dq axis voltage; i dh 、i qh is the dq axis current under high frequency excitation; L dh , L qh is the dq axis high frequency inductance.

[0064] Convert the high-frequency dq axis voltage equation (4) to the αβ axis system:

[0065]

[0066] In the formula, R(θ e ) is the transformation matrix from the dq axis system to the αβ axis system;

[0067]

[0068] Convert (5) into the high-frequency αβ current equation:

[0069]

[0070] The high-frequency αβ current equation is obtained:

[0071]

[0072] In the formula, i αh 、i βh is the high-frequency current of αβ axis; u αh 、u βh is the high frequency voltage of αβ axis; L avg =(L dh +L qh ) / 2 is the average inductance; L dif =(L dh -L qh ) / 2 is the differential inductance; θ e It is the angle between the rotating shaft system and the stationary shaft system, that is, the rotor position angle.

[0073] Since the sampling frequency is higher than the high-frequency injection square wave frequency, di / dt can be approximated as Δi / Δt. From (8), we can get the high-frequency αβ axis current change signal Δi αh , Δi βh :

[0074]

[0075] In the formula, Δi αh , Δi βh is the difference in high-frequency current change on the αβ axis, and ΔT is the time difference corresponding to the current change.

[0076] It can be seen that at high frequency αβ axis current change signal Δi αh , Δi βh Contains the rotor position information θ e .

[0077] Step S2: Convert the high-frequency αβ axis current change signal Δi αh , Δi βh The estimated rotor position can be obtained through the phase-locked loop and estimated rotor position

[0078] Traditional high-frequency square wave injection sensorless control can be divided into: injecting high-frequency square wave voltage signal on the d-axis and injecting high-frequency square wave voltage signal on the q-axis. The phase-locked loop structures obtained by the above two methods are different. The following is a specific analysis:

[0079] Inject a high-frequency square wave voltage into the d-axis:

[0080]

[0081] Where U in is the voltage amplitude of the injected high-frequency square wave; k is the number of half cycles of the high-frequency square wave injection period.

[0082] The high-frequency square wave voltage signal (10) of the d-axis is converted to the αβ-axis system to obtain the high-frequency voltage signal of the αβ-axis system:

[0083]

[0084] Substituting the αβ axis high-frequency voltage signal (11) into the high-frequency αβ axis current change signal equation (9), we can obtain the relationship between the αβ axis current change value and the rotor position:

[0085]

[0086] In the formula, the relationship coefficient between the d-axis injection current change and the rotor position is

[0087] Then we get the rotor position error expression, which is also the phase-locked loop expression determined based on the relationship between high-frequency current and rotor position:

[0088]

[0089] In the formula, θ err is the rotor position error, To estimate the angle between the rotating coordinate system and the actual stationary coordinate system, that is, to estimate the rotor position angle.

[0090] Inject a high-frequency square wave voltage into the q-axis:

[0091]

[0092] Convert the high-frequency square wave voltage signal (14) of the q axis to the αβ axis system:

[0093]

[0094] Substituting the αβ axis high-frequency voltage signal (15) into the high-frequency αβ axis current change signal equation (9), we can obtain the expression of the relationship between the αβ axis current change value and the rotor position:

[0095]

[0096] In the formula, the relationship coefficient between the q-axis injection current change and the rotor position is

[0097] The rotor position error expression is obtained, that is, the phase-locked loop expression is determined according to the relationship between high-frequency current and rotor position:

[0098]

[0099] In the formula, θ err is the rotor position estimation error; To estimate the rotor position.

[0100] The rotor position error is adjusted through PI to obtain the estimated speed. The estimated speed is integrated to obtain the estimated rotor position, that is, the angle between the estimated rotating coordinate system and the actual stationary coordinate system, to achieve sensorless control.

[0101] Step S3: Due to the influence of the dq axis coupling, when the high-frequency square wave voltage is injected into the d-axis or the q-axis alone, the high-frequency voltage value is not completely a high-frequency square wave signal.

[0102] When a high-frequency square wave is injected into the d-axis, a small high-frequency voltage will be excited on the q-axis due to the influence of the dq-axis coupling. Therefore, the d-axis high-frequency voltage is corrected to the following expression:

[0103]

[0104] Among them, δ is the minimum value.

[0105] Convert the high-frequency square wave voltage value (18) of the dq axis to the αβ axis system:

[0106]

[0107] After correction, the αβ axis high-frequency voltage correction value (19) is substituted into the high-frequency αβ axis current change signal equation (9), and the expression of the relationship between the αβ axis current change value and the rotor position is obtained:

[0108]

[0109] In the formula, the relationship coefficient between the current change and the rotor position after the d-axis injection voltage correction is To improve the compensation angle of the phase-locked loop structure;

[0110] The rotor position error expression is obtained:

[0111]

[0112] When a high-frequency square wave is injected into the q-axis, a small high-frequency voltage will be excited on the d-axis due to the influence of the dq-axis coupling. Therefore, the q-axis high-frequency voltage is corrected to the following expression:

[0113]

[0114] Convert the high-frequency square wave voltage value of the dq axis to the αβ axis system:

[0115]

[0116] Substituting the αβ axis high-frequency voltage correction value (23) into the high-frequency αβ axis current change signal equation (9), the relationship expression between the αβ axis current change value and the rotor position is obtained:

[0117]

[0118] In the formula, the relationship coefficient between the current change and the rotor position after the q-axis injection voltage correction is To improve the compensation angle of the phase-locked loop structure.

[0119] The rotor position error expression is obtained:

[0120]

[0121] When performing sensorless control of single-axis injection, injection can be performed on the d-axis or the q-axis. The two traditional phase-locked loop structures are different, and neither considers the role of the synchronous reluctance motor coupling effect. The high-frequency square wave voltage signal is not a high-frequency voltage value, so the two situations are analyzed separately.

[0122] Therefore, when a high-frequency square wave is injected into the d-axis, the improved phase-locked loop structure is obtained through the modified high-frequency voltage expression to obtain the rotor position error θ err The rotor position error is adjusted by PI to obtain the estimated speed, and the estimated rotor position is obtained by integrating the estimated rotor, that is, the angle between the estimated rotating coordinate system and the actual stationary coordinate system, to achieve sensorless control.

[0123] When a high-frequency square wave is injected into the q-axis, the rotor position error θ is obtained by obtaining an improved phase-locked loop structure through the modified high-frequency voltage expression. err The rotor position error is adjusted by PI to obtain the estimated speed, and the estimated rotor position is obtained by integrating the estimated rotor, that is, the angle between the estimated rotating coordinate system and the actual stationary coordinate system, to achieve sensorless control.

[0124] An improved phase-locked loop structure is obtained from the rotor position error expression. The output rotor position error is adjusted by PI to obtain the estimated speed, and the estimated speed is integrated to obtain the estimated rotor position.

[0125] The sub-technical solution of this embodiment can reduce the rotor error and make the estimated rotor position closer to the actual rotor position, thereby achieving more accurate sensorless control.

[0126] Combination Figure 1 , Figure 2 and Figure 4 , Figure 5 , Figure 1 and Figure 2 A high-frequency square wave signal is injected into the d-axis and an improved phase-locked loop is used for sensorless control. The three-phase current output by the synchronous reluctance motor is sampled to obtain the three-phase current data. The three-phase current is transformed by CLARK to obtain the αβ axis current i α and i β , the current and its lagging half-cycle signal are processed to obtain the high-frequency αβ axis current i αh and i βh The αβ axis current is transformed by PARK to obtain the dq axis current i d and i q The fundamental frequency dq axis current i is obtained by processing the current and its lagging half cycle signal df and i qf . will i αh and i βh Subtracting this hysteresis current yields Δi αh and Δiβh The resulting current change is passed through Figure 2 The improved phase-locked loop obtains the estimated speed and estimated rotor position, makes a difference between the estimated speed and the reference speed, obtains the reference torque at the moment through the speed loop, determines the dq axis current distribution according to the maximum torque current ratio control (MTPA), obtains the dq axis voltage through the current loop, and processes the signal through SVPWM to obtain the DC voltage source U dc The processed switching signals are used to control the synchronous reluctance motor for sensorless control. Figure 4 and Figure 5 A high frequency square wave signal is injected into the q-axis to perform sensorless control using an improved phase-locked loop.

[0127] refer to Figure 3 and Figure 6 , is an embodiment of the present invention, and provides a sensorless control method for a synchronous reluctance motor based on an improved phase-locked loop structure. In order to further verify the beneficial effects of the present invention, a scientific demonstration is carried out through simulation experiments as follows:

[0128] like Figure 3 The figure shows the rotor position error Simulink simulation diagram of the synchronous reluctance motor sensorless control method based on the improved phase-locked loop structure. Figure 3 It can be seen that in the steady-state operation stage, the difference between the estimated rotor position and the actual rotor position obtained by the traditional phase-locked loop is 0.1 (ie 5.7°). Using the improved phase-locked loop processing, the average error between the estimated rotor position and the actual rotor position can be made 0.

[0129] like Figure 6 The figure shows the rotor position error Simulink simulation diagram of the synchronous reluctance motor sensorless control method based on the improved phase-locked loop structure. Figure 3 It can be seen that: in the steady-state operation stage, the difference between the estimated rotor position and the actual rotor position obtained by the traditional phase-locked loop is 0.06 (i.e. 3.4°). Using the improved phase-locked loop processing, the average error between the estimated rotor position and the actual rotor position can be made 0.

[0130] Embodiment 2

[0131] The purpose of this embodiment is to provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above method when executing the program.

[0132] Embodiment 3

[0133] The purpose of this embodiment is to provide a computer-readable storage medium.

[0134] A computer-readable storage medium stores a computer program, which executes the steps of the above method when executed by a processor.

[0135] Embodiment 4

[0136] The purpose of this embodiment is to provide a sensorless control system for a reluctance motor based on high-frequency voltage correction, including:

[0137] The three-phase current data sampling module is configured to: sample the three-phase current output by the synchronous reluctance motor to obtain three-phase current data;

[0138] The three-phase current data processing module is configured to: transform the three-phase current to obtain the αβ axis current;

[0139] The high-frequency αβ axis current is obtained by processing the αβ axis current and its lagging half-cycle signal;

[0140] The αβ axis current is transformed to obtain the dq axis current, and the current and its lagging half cycle signal are processed to obtain the fundamental frequency dq axis current;

[0141] Subtract the high-frequency αβ axis current from the hysteresis current to obtain the current variation;

[0142] The speed and rotor position estimation module is configured to: process the obtained current variation through a phase-locked loop structure to obtain an estimated speed and an estimated rotor position;

[0143] The control module is configured to: process the estimated rotation speed and the estimated rotor position to obtain a switching signal, wherein the switching signal is used to control the synchronous reluctance motor.

[0144] Embodiment 5

[0145] The purpose of this embodiment is to provide a computer program product containing instructions, which, when running on a computer, enables the computer to execute the methods and functions involved in any of the above embodiments.

[0146] The steps involved in the apparatus of the above embodiment correspond to the method embodiment 1, and the specific implementation method can refer to the relevant description part of embodiment 1. The term "computer-readable storage medium" should be understood as a single medium or multiple media including one or more instruction sets; it should also be understood to include any medium that can store, encode or carry an instruction set for execution by a processor and enable the processor to execute any method in the present invention.

[0147] Those skilled in the art should understand that the modules or steps of the present invention described above can be implemented by a general-purpose computer device, or alternatively, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0148] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A sensorless control method for a reluctance motor based on high frequency voltage correction, characterized in that: include: Sampling the three-phase current output by the synchronous reluctance motor to obtain three-phase current data; The three-phase current is transformed to obtain the αβ axis current; The high-frequency αβ axis current is obtained by processing the αβ axis current and its lagging half-cycle signal; The αβ axis current is transformed to obtain the dq axis current, and the current and its lagging half cycle signal are processed to obtain the fundamental frequency dq axis current; Subtract the high-frequency αβ axis current from the hysteresis current to obtain the current variation; The obtained current variation is processed through a phase-locked loop structure to obtain an estimated speed and an estimated rotor position; The estimated speed and the estimated rotor position are processed to obtain a switching signal, which is used to control the synchronous reluctance motor.

2. The sensorless control method for a reluctance motor based on high frequency voltage correction according to claim 1, characterized in that: The estimated speed and estimated rotor position are processed to obtain a switching signal, specifically: The estimated speed is subtracted from the reference speed, and the dq axis current distribution is determined according to the maximum torque current ratio control. The dq axis voltage is obtained through the current loop, and the signal is processed to obtain a switching signal for processing the DC voltage source, which is used to control the synchronous reluctance motor.

3. The sensorless control method for a reluctance motor based on high frequency voltage correction according to claim 1, characterized in that: The obtained current variation is processed through a phase-locked loop structure to obtain the estimated speed and estimated rotor position, and the d-axis high-frequency voltage is corrected to the following expression: Among them, δ is the minimum value, u dh 、u qh is the high frequency d and q axis voltage, U in is the injected high-frequency square wave voltage amplitude, and k is the number of half cycles of the high-frequency square wave injection period.

4. The sensorless control method for a reluctance motor based on high frequency voltage correction as claimed in claim 3, characterized in that: Based on the d-axis high-frequency voltage correction expression, the rotor position error expression is: Among them, Δi αh , Δi βh is the high frequency α and β axis current change value, θ e is the angle between the rotating shaft system and the stationary shaft system, that is, the rotor position angle, To estimate the angle between the rotating coordinate system and the actual stationary coordinate system, that is, to estimate the rotor position angle, θ err is the rotor position error, To improve the compensation angle of the phase-locked loop structure, K d2 It is the coefficient of relationship between the current change and the rotor position after the d-axis injection voltage correction.

5. The sensorless control method for a reluctance motor based on high frequency voltage correction according to claim 1, characterized in that: The q-axis high-frequency voltage is corrected to the following expression: Among them, δ is the minimum value, u dh 、u qh is the high frequency d and q axis voltage, U in is the injected high-frequency square wave voltage amplitude, and k is the number of half cycles of the high-frequency square wave injection period.

6. The sensorless control method for a reluctance motor based on high frequency voltage correction according to claim 1, characterized in that: The rotor position error expression is: Among them, Δi αh , Δi βh is the high frequency α and β axis current change value, θ e is the angle between the rotating shaft system and the stationary shaft system, that is, the rotor position angle, To estimate the angle between the rotating coordinate system and the actual stationary coordinate system, that is, to estimate the rotor position angle, θ err is the rotor position error, To improve the compensation angle of the phase-locked loop structure, K q2 It is the relationship coefficient between the current change and the rotor position after the q-axis injection voltage correction.

7. A sensorless control system for a reluctance motor based on high frequency voltage correction, characterized in that: include: The three-phase current data sampling module is configured to: sample the three-phase current output by the synchronous reluctance motor to obtain three-phase current data; The three-phase current data processing module is configured to: transform the three-phase current to obtain the αβ axis current; The high-frequency αβ axis current is obtained by processing the αβ axis current and its lagging half-cycle signal; The αβ axis current is transformed to obtain the dq axis current, and the current and its lagging half cycle signal are processed to obtain the fundamental frequency dq axis current; Subtract the high-frequency αβ axis current from the hysteresis current to obtain the current variation; The speed and rotor position estimation module is configured to: process the obtained current variation through a phase-locked loop structure to obtain an estimated speed and an estimated rotor position; The control module is configured to: process the estimated rotation speed and the estimated rotor position to obtain a switching signal, wherein the switching signal is used to control the synchronous reluctance motor.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the method described in any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method described in any one of claims 1 to 6 are performed.

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