Control method for dual three-phase permanent magnet synchronous motor with 30-degree phase shift angle

Abstract

The invention discloses a control method for a dual three-phase permanent magnet synchronous motor with a 30-degree phase shift angle, solves the problem that an existing DTP-PMSM current reconstruction control system needs a plurality of current sensors, and belongs to the field of motor driving. The method comprises the steps of combining carrier phase shift with AZSPWM based on a sampling mode of acquiring the sum of currents of B, C, Y and Z lower bridge arms in a single path and spatial distribution characteristics of two sets of windings of a 30-degree phase shift angle dual three-phase motor, constructing a reconstruction region, and constructing a six-phase current reconstruction expression of the motor in each reconstruction region; selecting a corresponding six-phase current reconstruction expression according to the reconstruction area where the reference voltage vector is located and the ISAMPLE collected in real time, and reconstructing the six-phase current; and controlling the motor according to the reconstructed six-phase current. According to the invention, a d-axis resolver error is eliminated by adopting resolver compensation, so that the acquired rotor position angle is more accurate; according to the method, the process of outputting a current loop to pulse width modulation setting is simplified into single-step operation through VSD-2dq equivalent transformation.

Description

Technical Field

[0001] The invention relates to a 30° phase shift angle dual three-phase permanent magnet synchronous motor control method based on single-channel sampling, and belongs to the field of motor drive. Background Art

[0002] In industrial production, the quality of motor drive systems is determined by a number of performance indicators, especially in aerospace, ships, electric vehicles and other application fields that have strict requirements on torque pulsation, power density and efficiency, low torque pulsation and high power density integrated design are particularly important. Compared with traditional motors, the dual-three-phase permanent magnet synchronous motor (DTP-PMSM) can effectively realize power integration, and the unique winding structure of the 30° phase shift angle DTP-PMSM greatly reduces torque pulsation, which is a unique advantage.

[0003] In the DTP-PMSM dual closed-loop control system, six-phase currents need to be sampled to adjust the current and speed. Since both sets of windings are Y-connected and isolated from each other, at least four current sensors are required to complete the sampling, which greatly increases the weight and volume of the system, making it unfavorable for applications with high power density integration requirements. Current reconstruction technology is currently a research hotspot for reducing the number of sensors, but since the DTP-PMSM drive circuit is generally composed of two sets of three-phase full-bridge inverter circuits, the traditional phase current reconstruction method is still based on three phases, and the two sets of windings are sampled independently. The location and number of current sensors need to be further optimized.

[0004] 30° phase shift angle DTP-PMSM has 2 6 =64 combinations of voltage space vectors, with high degrees of freedom and difficult reconstruction area planning. Moreover, the current flows through different paths under different voltage vectors, and the sampling branches corresponding to the current sensors under different paths have different phase current information. Single resistor sampling will limit the phase current information. For this reason, some scholars use dynamic zero-state PWM to construct reconstruction conditions, which can better achieve complete current reconstruction, but some sector PWMs are no longer symmetrical, resulting in the generation of even switching harmonics. Therefore, there is still room for optimization of the pulse modulation method.

[0005] In order to further suppress system harmonics, some scholars have proposed vector space decomposition (VSD) control based on the characteristics of 30° phase-shift angle DTP-PMSM. This control can separate the harmonic plane through coordinate transformation and has a suppressive effect on specific harmonics. At present, the 30° phase-shift angle DTP-PMSM in actual engineering applications is still mainly based on three-phase independent SVM. The reference voltage vector obtained by the current loop in the dq-z1z2 coordinate system must first be equivalent to the abc-xyz coordinate system, and then the two three phases are transformed into the dq coordinate system for independent SVM, and the transformation calculation process can be simplified.

[0006] In actual engineering applications, position sensors composed of resolver chips are often used to collect the motor rotor position angle. The main principle of the resolver is to transfer the voltage on the primary side of the rotating rotor to two mutually perpendicular secondary coils through electromagnetic induction. The secondary voltage and the primary voltage have a sine and cosine quantitative relationship, and the size of the position angle is inferred by a specific algorithm. During the operation of the motor, it is found that there is a back electromotive force on the d-axis, which means that there is a certain error between the rotor position angle obtained by the resolver and the actual rotor position angle, which has a great impact on the subsequent coordinate change and control and adjustment process. Therefore, it is necessary to study the method of eliminating the error.

[0007] Defects of the prior art:

[0008] The DTP-PMSM current reconstruction control system requires multiple current sensors; the 30° phase shift angle DTP-PMSM space vector combination has high degrees of freedom, the reconstruction area planning is difficult, and modifying the PWM structure reconstruction conditions will bring about problems such as even harmonics; the reference voltage vector to two groups of SVM modulation operations in the VSD coordinate system are complex; the rotor position angle collected by the position sensor has errors. Summary of the invention

[0009] Aiming at the problem that the existing DTP-PMSM current reconstruction control system requires multiple current sensors, the present invention provides a 30° phase shift angle dual three-phase permanent magnet synchronous motor control method.

[0010] A control method for a dual three-phase permanent magnet synchronous motor with a 30° phase shift angle of the present invention comprises:

[0011] Based on a single channel to collect the sum of the lower arm currents of B, C, Y, and Z I SAMPLE The sampling method and the spatial distribution characteristics of the two sets of windings of the dual three-phase motor with a phase shift angle of 30° are used to combine the carrier phase shift with AZSPWM to construct the reconstruction area, and the six-phase current reconstruction expression of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30° in each reconstruction area is constructed;

[0012] According to the reconstruction area where the reference voltage vector is located and the real-time acquisition of ISAMPLE , select the corresponding six-phase current reconstruction expression and reconstruct the six-phase current;

[0013] The dual three-phase permanent magnet synchronous motor with a 30° phase shift angle is controlled according to the reconstructed six-phase current.

[0014] Preferably, the method for constructing the reconstruction region comprises:

[0015] Two groups of three-phase SVM strategies are used to plan the voltage space. According to the spatial distribution characteristics of the two sets of windings of the 30° phase shift angle dual three-phase permanent magnet synchronous motor, combined with the three-phase independent modulation idea, the switching vector with 64 degrees of freedom is simplified into two groups of adjacent six-sector vector combinations:

[0016]

[0017] Where U dc is the bus voltage; S A , S B , S C , S X , S Y , S Z are the switching functions of the six-phase bridge arms, respectively. A value of 0 represents that the lower tube of the bridge arm is turned on, and a value of 1 represents that the upper tube of the bridge arm is turned on; U 1k is the space vector formed by the first set of three-phase windings ABC; U 2k The space vector formed by the second three-phase winding XYZ, k = 0, 1, 2, 3, 4, 5, 6, 7;

[0018] When S A =0, S B =0, S C =0 when the corresponding voltage vector U 10 ;

[0019] When S A =1, S B =0, S C =0 when the corresponding voltage vector U 11 ;

[0020] When S A =1, S B =1, S C =0 when the corresponding voltage vector U 12 ;

[0021] When S A =0, S B =1, S C =0 when the corresponding voltage vector U 13 ;

[0022] When S A =0, S B=1, S C =1 corresponds to the voltage vector U 14 ;

[0023] When S A =0, S B =0, S C =1 corresponds to the voltage vector U 15 ;

[0024] When S A =1, S B =0, S C =1 corresponds to the voltage vector U 16 ;

[0025] When S A =1, S B =1, S C =1 corresponds to the voltage vector U 17 ;

[0026] When S X =0, S Y =0, S Z =0 when the corresponding voltage vector U 20 ;

[0027] When S X =1, S Y =0, S Z =0 when the corresponding voltage vector U 21 ;

[0028] When S X =1, S Y =1, S Z =0 when the corresponding voltage vector U 22 ;

[0029] When S X =0, S Y =1, S Z =0 when the corresponding voltage vector U 23 ;

[0030] When S X =0, S Y =1, S Z =1 corresponds to the voltage vector U 24 ;

[0031] When S X =0, S Y =0, S Z =1 corresponds to the voltage vector U 25 ;

[0032] When S X =1, S Y =0, SZ =1 corresponds to the voltage vector U 26 ;

[0033] When S X =1, S Y =1, S Z =1 corresponds to the voltage vector U 27 ;

[0034] The two sets of three-phase winding space vectors are integrated into the same phase space plane, and 12 groups of reconstructed regions in the phase space are obtained after simplification:

[0035] The reconstructed region G1 is composed of the space vector U 11 with U 21 Surrounded by

[0036] The reconstructed region G2 is composed of the space vector U 12 with U 21 Surrounded by

[0037] The reconstructed region G3 is composed of the space vector U 12 with U 22 Surrounded by

[0038] The reconstructed region G4 is composed of the space vector U 13 with U 22 Surrounded by

[0039] The reconstruction region G5 is composed of the space vector U 13 with U 23 Surrounded by

[0040] The reconstruction region G6 is composed of the space vector U 14 with U 23 Surrounded by

[0041] The reconstruction region G7 is composed of the space vector U 14 with U 24 Surrounded by

[0042] The reconstruction region G8 is composed of the space vector U 15 with U 24 Surrounded by

[0043] The reconstruction region G9 is composed of the space vector U 15 with U 25 Surrounded by

[0044] The reconstruction region G10 is composed of the space vector U 16 with U 25 Surrounded by

[0045] The reconstruction region G11 is composed of the space vector U 16 with U 26 Surrounded by

[0046] The reconstruction region G12 is composed of the space vector U 11 with U 26 Surrounded.

[0047] As a preference, the six-phase current reconstruction expression of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30° in each reconstruction region is constructed as follows:

[0048]

[0049]

[0050]

[0051] Among them, U 1i U 2j Indicates the switch combinations corresponding to two sets of three-phase windings, i=0,1,2,3,4,5,6,7, j=0,1,2,3,4,5,6,7;

[0052] I1, I2, I3, and I4 represent the currents sampled by the four sampling vector combinations respectively;

[0053] i A It represents the current of phase A in the first three-phase winding ABC;

[0054] i B It represents the current of phase B in the first three-phase winding ABC;

[0055] i C It represents the current of phase C in the first three-phase winding ABC;

[0056] i X Indicates the current of phase X in the second three-phase winding XYZ;

[0057] i Y Indicates the current of the Y phase in the second three-phase winding XYZ

[0058] i Z Represents the current of phase Z in the second set of three-phase winding XYZ.

[0059] Preferably, when controlling the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30° according to the reconstructed six-phase current, reconstructed hybrid pulse width modulation RHPWM is used for modulation, including:

[0060] CPS-PWM is used in all reconstruction areas, and the carrier phase of the second three-phase winding XYZ is delayed by T s / 4, T s Indicates the carrier period;

[0061] The reference voltage vector is modulated using AZSPWM in the reconstruction areas G1, G2, G6, G7, G8, and G12;

[0062] The reference voltage vector is modulated using SVPWM when reconstructing areas G3, G4, G5, G9, G10, and G11.

[0063] Preferably, the method for controlling a 30° phase shift angle dual three-phase permanent magnet synchronous motor according to the reconstructed six-phase current includes:

[0064] According to the working condition of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30°, the initial position angle θ0 of the motor is subjected to resolver compensation to obtain the actual speed after resolver compensation;

[0065] The difference between the motor given speed and the actual speed after resolver compensation is sent to the speed controller ASR-PI to obtain the motor torque current given value; the reconstructed six-phase current is transformed by VSD coordinates to obtain the motor current feedback value, including the torque current feedback value i q , flux current feedback value i d , mutually orthogonal harmonic current feedback values ​​i Z1 、i Z2 ;

[0066] The difference between the motor torque current set value and the motor current feedback value is sent to the current loop controller ACR-PI, and then the voltage set values ​​of the two sets of three-phase windings are obtained, including the torque voltage set value u q , flux voltage given value u d , mutually orthogonal harmonic voltage given value u z1 、u z2 ;

[0067] The obtained voltage given value is converted into two sets of three-phase SVM given values, and then reconstructed hybrid pulse width modulation RHPWM is performed to generate driving signals for two sets of three-phase windings to complete the drive control.

[0068] Preferably, the method for performing resolver compensation includes:

[0069] Calculate the back electromotive force e of the two sets of three-phase windings output by the current loop controller ACR-PI on the d axis respectively d1 、e d2 , and sum e ds-err :

[0070]

[0071] In the formula, K i1 , K i2 is the proportional coefficient of the current loop controller ACR-PI, is the d-axis current calibration value of the two sets of three-phase windings, id1 、i d2 is the actual current value of the d-axis of the two sets of three-phase windings, and dt is the integral calculation period;

[0072] According to the back electromotive force e of the two sets of three-phase windings d1 、e d2 , adjust the initial position angle θ0 of the motor accordingly so that the error and e ds-err When the minimum value is reached, the compensated position angle θ is saved, and the actual speed after resolver compensation is obtained according to the position angle θ.

[0073] As a preferred method, the voltage given value is subjected to VSD-2DQ equivalent transformation to obtain two sets of three-phase SVM given values ​​u d1 、u q1 、u d2 、u q2 :

[0074]

[0075] Wherein, θ represents the electrical angle of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30°.

[0076] The beneficial effects of the present invention are as follows: the present invention only needs a single current sensor or a single impedance sampling independent branch to realize six-phase current reconstruction; the present invention combines the structural characteristics of the 30° phase shift angle DTP-PMSM, re-divides the reconstruction area into 12 groups, and adopts a variety of PWM combinations to construct six-phase current reconstruction conditions; the present invention adopts resolver compensation to eliminate the d-axis resolver error, so that the collected rotor position angle is more accurate; the present invention simplifies the process of outputting the current loop to the pulse width modulation given by VSD-2dq equivalent transformation into a single-step operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 This is the current reconstruction topology diagram of DTP-PMSM with a 30° phase shift angle.

[0078] Figure 2 This is a simplified diagram of the space voltage vector of DTP-PMSM with a phase shift angle of 30°.

[0079] Figure 3 This is the simplified and reconstructed sector distribution diagram of the DTP-PMSM with a phase shift angle of 30°.

[0080] Figure 4 The control block diagram of the DTP-PMSM current reconstruction method with a 30° phase shift angle.

[0081] Figure 5(a) is a schematic diagram of the G1 zero vector reconstruction area sampling.

[0082] FIG5( b ) is a schematic diagram of sampling of the normal reconstruction area of ​​G3.

[0083] Figure 6(a) is a current waveform diagram of a single current sensor sampling current.

[0084] Figure 6(b) shows the current diagram when a single current sensor samples four times per switching cycle.

[0085] Figure 7 ABC, XYZ real phase current and reconstructed current waveform.

[0086] Figure 8 is the error between the real current and the reconstructed current of phase A. DETAILED DESCRIPTION

[0087] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments 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.

[0088] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0089] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0090] The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method of this embodiment includes:

[0091] Step 1: Collect the sum of the lower arm currents of B, C, Y, and Z based on a single channel. SAMPLE The sampling method and the spatial distribution characteristics of the two sets of windings of the dual three-phase motor with a phase shift angle of 30° are used to combine the carrier phase shift with AZSPWM to construct the reconstruction area, and the six-phase current reconstruction expression of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30° in each reconstruction area is constructed; specifically:

[0092] Modify the current sampling topology, move the X-phase bridge arm between the AB phases, and use a single current Hall sensor or a single resistor to collect the sum of the bridge arm currents of B, C, Y, and Z. The corresponding relationship between the current sensor sampling results and the phase current under different voltage vectors is:

[0093] I SAMPLE =I sum-ABC +I sum-XYZ =S B i B +S C i C +S Y i Y +S Z i Z (1)

[0094] In the formula, S A , S B , S C , S X , S Y , S Z are the switching functions of the six-phase bridge arms, respectively. A value of 0 represents that the lower tube of the bridge arm is turned on, and a value of 1 represents that the upper tube of the bridge arm is turned on; i A represents the current of phase A in the first three-phase winding ABC; i B represents the current of phase B in the first three-phase winding ABC; i C represents the current of phase C in the first three-phase winding ABC; i X represents the current of phase X in the second three-phase winding XYZ; i Y represents the current of phase Y in the second three-phase winding XYZ; i Z Indicates the current of phase Z in the second three-phase winding XYZ; I sum-ABC The current sensor sampling results of the ABC three-phase under different voltage vectors; I sum-XYZ The current sensor sampling results of the XYZ three-phase under different voltage vectors.

[0095] Two groups of three-phase SVM strategies are used to replan the voltage space. According to the spatial distribution characteristics of the 30° phase-shift DTP-PMSM winding, the switching vector with 64 degrees of freedom is simplified into two groups of adjacent six-sector vector combinations in combination with the three-phase independent modulation idea.

[0096]

[0097] Where U dc is the bus voltage; U 1k is the space vector formed by the first set of three-phase windings ABC; U 2k The space vector formed by the second three-phase winding XYZ, k = 0, 1, 2, 3, 4, 5, 6, 7;

[0098] When S A =0, S B =0, S C =0 when the corresponding voltage vector U 10 ; When S A =1, S B =0, S C =0 when the corresponding voltage vector U 11 ; When S A =1, S B =1, S C =0 when the corresponding voltage vector U 12 ; When S A =0, S B =1, S C=0 when the corresponding voltage vector U 13 ; When S A =0, S B =1, S C =1 corresponds to the voltage vector U 14 ; When S A =0, S B =0, S C =1 corresponds to the voltage vector U 15 ; When S A =1, S B =0, S C =1 corresponds to the voltage vector U 16 ; When S A =1, S B =1, S C =1 corresponds to the voltage vector U 17 ; When S X =0, S Y =0, S Z =0 when the corresponding voltage vector U 20 ; When S X =1, S Y =0, S Z =0 when the corresponding voltage vector U 21 ; When S X =1, S Y =1, S Z =0 when the corresponding voltage vector U 22 ; When S X =0, S Y =1, S Z =0 when the corresponding voltage vector U 23 ; When S X =0, S Y =1, S Z =1 corresponds to the voltage vector U 24 ; When S X =0, S Y =0, S Z =1 corresponds to the voltage vector U 25 ; When S X =1, S Y =0, S Z =1 corresponds to the voltage vector U 26 ; When S X =1, S Y =1, S Z =1 corresponds to the voltage vector U 27 .

[0099] According to equation (2), the two sets of three-phase winding space vectors are integrated into the same phase space plane. After simplification, 12 groups of reconstruction regions in the phase space are obtained, and each current reconstruction region is surrounded by two space vectors.

[0100] The reconstructed region G1 is composed of the space vector U 11 with U 21 The reconstructed region G2 is surrounded by the space vector U 12 with U 21 The reconstructed region G3 is surrounded by the space vector U 12 with U 22 The reconstruction region G4 is surrounded by the space vector U 13 with U 22 The reconstruction region G5 is surrounded by the space vector U 13 with U 23 The reconstruction region G6 is surrounded by the space vector U 14 with U 23 The reconstruction region G7 is surrounded by the space vector U 14 with U 24 The reconstruction region G8 is surrounded by the space vector U 15 with U 24 The reconstruction region G9 is surrounded by the space vector U 15 with U 25 The reconstruction region G10 is surrounded by the space vector U 16 with U 25 The reconstruction region G11 is surrounded by the space vector U 16 with U 26 The reconstruction region G12 is surrounded by the space vector U 11 with U 26 Surrounded.

[0101] The three-phase independent SVM strategy is adopted to construct the reconstruction conditions by flexibly allocating three modulation modes, namely CPS-PWM, AZSPWM and SVPWM, according to the reconstruction area where the reference voltage is located.

[0102] CPS-PWM is used in all reconstruction areas, and the carrier phase of the XYZ winding is delayed by T / 4.

[0103] In the reconstruction area G1, AZSPWM is applied to transform the zero vector U 10 , U 17 , U 20 , U 27 Replace the opposite effective vector U 16 , U 13 , U 22 , U 25 .

[0104] In the reconstruction area G2, AZSPWM is applied to transform the zero vector U10 , U 17 , U 20 , U 27 Replace the opposite effective vector U 16 , U 13 , U 26 , U 23 .

[0105] In the reconstruction area G6, AZSPWM is applied to transform the zero vector U 10 , U 17 , U 20 , U 27 Replace the opposite effective vector U 12 , U 15 , U 22 , U 25 .

[0106] In the reconstruction area G7, AZSPWM is applied to transform the zero vector U 10 , U 17 , U 20 , U 27 Replace the opposite effective vector U 16 , U 13 , U 22 , U 25 .

[0107] In the reconstruction area G8, AZSPWM is applied to transform the zero vector U 10 , U 17 , U 20 , U 27 Replace the opposite effective vector U 16 , U 13 , U 26 , U 23 .

[0108] In the reconstruction area G12, AZSPWM is applied to transform the zero vector U 10 , U 17 , U 20 , U 27 Replace the opposite effective vector U 12 , U 15 , U 22 , U 25 .

[0109] The reconstruction areas G1, G2, G6, G7, G8, and G12 using AZSPWM are collectively referred to as zero vector reconstruction areas; the normal reconstruction areas G3, G4, G5, G9, G10, and G11 are modulated using traditional SVPWM.

[0110] Four sampling currents are obtained by using single resistor sampling at the switch combinations corresponding to different voltage vectors.

[0111] The sampling switch combination corresponding to group G1 is U 16 U 21 , U 13 U 21 , U 11 U 22 , U 11 U 25 ;

[0112] The sampling switch combination corresponding to group G2 is U 16 U 21 , U 13 U 21 , U 12 U 26 , U 12 U 23 ;

[0113] The sampling switch combination corresponding to group G3 is U 10 U 22 , U 17 U 22 , U 12 U 20 , U 12 U 27 ;

[0114] The sampling switch combination corresponding to group G4 is U 10 U 22 , U 17 U 22 , U 13 U 20 , U 13 U 27 ;

[0115] The sampling switch combination corresponding to group G5 is U 10 U 23 , U 17 U 23 , U 13 U 20 , U 13 U 27 ;

[0116] The sampling switch combination corresponding to group G6 is U 12 U 23 , U 15 U 23 , U 14 U 22 , U 14 U 25 ;

[0117] The sampling switch combination of G7 group is U 16 U 24 , U 13 U24 , U 14 U 22 , U 14 U 25 ;

[0118] The sampling switch combination corresponding to group G8 is U 16 U 24 , U 13 U 24 , U 15 U 26 , U 15 U 23 ;

[0119] The sampling switch combination corresponding to group G9 is U 10 U 25 , U 17 U 25 , U 15 U 20 , U 15 U 27 ;

[0120] The sampling switch combination corresponding to the G10 group is U 10 U 25 , U 17 U 25 , U 16 U 20 , U 16 U 27 ;

[0121] The sampling switch combination corresponding to group G11 is U 10 U 26 , U 17 U 26 , U 16 U 20 , U 16 U 27 ;

[0122] The sampling switch combination corresponding to group G12 is U 12 U 26 , U 15 U 26 , U 11 U 22 , U 11 U 25 .

[0123] According to Table 1, the six-phase currents of DTP-PMSM are calculated using the four sampled currents.

[0124] Table 1 Correspondence between current sensor sampling results and phase current under different voltage vectors

[0125]

[0126]

[0127]

[0128]

[0129] Step 2: Based on the reconstruction area where the reference voltage vector is located and the real-time collected I SAMPLE , select the corresponding six-phase current reconstruction expression and reconstruct the six-phase current;

[0130] Step 3: Control the dual three-phase permanent magnet synchronous motor with a 30° phase shift angle according to the reconstructed six-phase current:

[0131] According to the working condition of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30°, the initial position angle θ0 of the motor is subjected to resolver compensation to obtain the actual speed after resolver compensation;

[0132] In the DTP-PMSM control system, the motor sampling current value is converted into a voltage in the dual dq coordinate system through the VSD-2DQ transformation. The d-axis of the two sets of motor windings will generate back electromotive force due to the resolver angle error. The output back electromotive force e of the current loop controller on the d-axis is calculated respectively. d1 、e d2 , and sum e ds-err :

[0133]

[0134] In the formula, K i1 , K i2 is the proportional coefficient of the current loop controller ACR-PI, is the d-axis current calibration value of the two sets of three-phase windings, i d1 、i d2 is the actual current value of the d-axis of the two sets of three-phase windings, and dt is the integral calculation period.

[0135] According to the calculated back electromotive force of the two d-axis, the initial recognition angle is adjusted accordingly so that the error and e ds-err When the minimum value is reached, the machine stops to save the identification angle and sets it as the initial angle of the DTP-PMSM to compensate for the resolver error angle.

[0136] The difference between the motor given speed and the actual speed after resolver compensation is sent to the speed controller ASR-PI to obtain the motor torque current given value; the reconstructed six-phase current is transformed by VSD coordinates to obtain the motor current feedback value, including the torque current feedback value i q , flux current feedback value i d , mutually orthogonal harmonic current feedback values ​​i Z1 、iZ2 ;

[0137] The difference between the motor torque current set value and the motor current feedback value is sent to the current loop controller ACR-PI, and then the voltage set values ​​of the two sets of three-phase windings are obtained, including the torque voltage set value u q , flux voltage given value u d , mutually orthogonal harmonic voltage given value u z1 、u z2 ;

[0138] The obtained voltage given value is converted into two sets of three-phase SVM given values, and then reconstructed hybrid pulse width modulation RHPWM is performed to generate driving signals for two sets of three-phase windings to complete the drive control.

[0139] The voltage reference given value in the VSD coordinate system output by the current loop controller is transformed into two sets of three-phase SVM given values ​​using the VSD-2DQ equivalent transformation formula (4). Finally, the six-phase bridge arm drive signal is generated through two sets of three-phase SVM strategies.

[0140]

[0141] The embodiment uses a dual three-phase permanent magnet synchronous motor with 15 pole pairs, a rotation speed of 125rpm, and a phase shift angle of 30° for simulation experiments. The switching frequency is 25kHz, and two sets of three-phase windings are independently connected in Y-type. Figure 4 As shown, the main control loop adopts vector space decomposition (VSD) dual closed-loop control.

[0142] Modify the current sampling topology. Give an example to illustrate the corresponding relationship between the switching function and the current sensor sampling current. When the first set of windings ABC acts as the switching vector U 11 When Figure 2 Know U 11 Corresponding switching function S A =1S B =0S C =0 Substituting it into formula (1), we can get I sum-ABC =0; if at this time the second set of three-phase winding XYZ action switching vector U 22 With the first set of three-phase winding switching vector U 11 Combined with each other, Figure 2 Know U 22 Corresponding switching function S X =1S Y =1S Z =0 Substituting it into formula (1), we can get I sum-XYZ =i Y , the two can be superimposed to obtain the current sensor sampling result is I SAMPLE =0+iY In this way, the DTP-PMSM voltage vector is split into two groups of three-phase SVM voltage vectors, and the voltage vectors of the two groups of three-phase SVMs each form a corresponding current in the three-phase winding, and the current sensor sampling current is generated after superposition. At the same time, the motor's rotation angle and speed are sampled.

[0143] Two groups of three-phase SVM strategies are used to replan the voltage space. Figure 2 As shown in the figure, according to the spatial distribution characteristics of the 30° phase shift angle DTP-PMSM winding, combined with formula (2), the second set of three-phase winding switch vectors are rotated 30° counterclockwise in the phase space relative to the first set of three-phase windings, and then the two are combined to form a new space vector planning. Each modulation sector is surrounded by two space vectors, and sectors I-XII correspond to the reconstruction areas G1-G12 respectively. Finally, 12 groups of reconstruction areas in the phase space are simplified. Each current reconstruction area is surrounded by two space vectors, and finally formed. Figure 3 Simplified reconstructed sector distribution diagram of DTP-PMSM with a phase shift angle of 30°.

[0144] In order to construct the current reconstruction conditions, a three-phase independent modulation strategy is adopted, and RHPWM is used to flexibly allocate four modulation modes including CPS-PWM, AZSPWM and SVPWM according to the reconstruction area where the reference voltage is located.

[0145] CPS-PWM is used in all reconstruction areas, and the carrier phase of the second winding is delayed by T / 4. AZSPWM is used in the zero vector reconstruction area. SVPWM is used in the normal reconstruction area.

[0146] Sampling is performed at four vector combinations to obtain the sampled current.

[0147] The six-phase currents of DTP-PMSM are calculated using four sampling currents according to Table 1. Taking the normal area, normal boundary blind area, zero vector modification area, and zero vector boundary area as examples, the process of reconstructing the six-phase currents using sampling currents is explained.

[0148] When the reference voltage is located in the zero vector reconstruction region G1, the PWM output is as shown in FIG5(a), and at this time, sampling is performed at the vector combination to obtain the sampled currents I1, I2, I3, and I4.

[0149] From Table 1, we can see that the relationship between the sampling current and the phase current is:

[0150]

[0151] According to the reconstruction equation provided in Table 1:

[0152]

[0153] By inputting the sampled current, the six-phase current can be calculated based on the sampled current.

[0154] When the reference voltage is located in the normal region G3 reconstruction group, the PWM output is shown in FIG5( b ), and at this time, sampling is performed at the vector combination to obtain the sampled currents I1 , I2 , I3 , and I4 .

[0155] From Table 1, we can see that the relationship between the sampling current and the phase current is:

[0156]

[0157] According to the reconstruction equation provided in Table 1:

[0158]

[0159] By inputting the sampled current, the six-phase current can be calculated based on the sampled current.

[0160] The final sampling current is shown in FIG6(a) and FIG6(b), and the current waveform is consistent with Table 1.

[0161] The reconstructed current and the actual current are as follows Figure 7 As shown in , the actual current and the reconstructed current have the same phase and amplitude. Figure 8 The reconstruction error is controlled within the allowable range and meets the reconstruction requirements.

[0162] According to formula (3), the sum of the output back electromotive force of the current loop controller on the two d axes is calculated by integration. ds-err , and because of the DTP-PMSM mathematical model, we can get:

[0163] e ds-err =ω e ψsin(θ err )(9)

[0164] In the formula, ω e is the speed, Ψ is the rotor flux, θ err is the resolver error angle (-π~π).

[0165] When e ds-err >0, θ err <0, the recognition angle should be increased; when e ds-err <0, θ err >0, the recognition angle should be reduced. Then judge e ds-err Is it less than the judgment threshold δ? If it is less than δ, delay 20 calculation cycles and continue to judge e ds-err Is it less than δ? Otherwise, return to continue the integral calculation. If after the delay, e ds-err<δ, the machine stops and saves the identification angle as the resolver error angle θ, and sets it as the compensated position angle θ of the DTP-PMSM. According to the position angle θ, the actual speed after resolver compensation is obtained.

[0166] The difference between the motor's given speed and actual speed is sent to the speed controller to obtain the motor's torque current setting.

[0167] The six-phase current is input into formula (10) for VSD transformation to obtain the torque current feedback value, flux current feedback value, and harmonic current feedback value in the VSD coordinate system.

[0168]

[0169] The difference between the feedback current and the given current is sent to the current loop controller to obtain the torque reference voltage, flux reference voltage and harmonic reference voltage in the VSD coordinate system.

[0170] The VSD-2DQ equivalent transformation of formula (4) is adopted to transform the reference voltage in the VSD coordinate system into two sets of three-phase reference voltages, which are sent to the three-phase SVM. Finally, the six-phase bridge arm drive signal is generated through two sets of three-phase SVM strategies to complete the DTP-PMSM motor drive.

[0171] The present embodiment is a 30° phase-shifted dual three-phase permanent magnet synchronous motor single current sensor sampling current reconstruction scheme and control system based on multiple pulse width modulation methods. The sampling topology is modified. The single current sensor perforates an independent branch and uses a single sampling resistor to sample the corresponding relationship between the sensor sampling current and the phase current. The rotation angle and speed of the motor are sampled at the same time. The initial recognition angle of the resolver is adjusted by an algorithm to control the d-axis back electromotive force to 0, thereby obtaining an accurate rotor position angle. The three-phase independent SVM strategy is adopted to re-plan the phase space according to the 30° phase-shifted DTP-PMSM space vector characteristics to obtain a reconstruction area. The carrier phase-shifted PWM (CPS-PWM) is used to lag the second three-phase winding XYZ carrier phase by a quarter cycle, and the dynamic zero state PWM (Active Zero State PWM) is used in a specific reconstruction area. StatePWM, AZSPWM) constructs reconstruction conditions; completes the six-phase current reconstruction based on the current reconstruction expressions in different reconstruction areas; sends the reconstructed current into the VSD control loop to generate a given reference voltage output in the VSD coordinate system; through VSD-2DQ equivalent transformation, two groups of three-phase SVM given values ​​are obtained through single-step calculation, and finally a 30° phase shift angle DTP-PMSM drive control system is constructed.

[0172] Since the reconstruction method of the present invention only involves reconstruction topology, modulation mode, control variables, and reconstruction method, this implementation has no constraints on the controller. This implementation is also applicable to applications where the speed loop controller uses an auto-disturbance rejection controller and the current loop controller uses a proportional resonant controller.

[0173] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. 30° phase shift angle dual three-phase permanent magnet synchronous motor control method, characterized in that: include: Based on a single channel to collect the sum of the lower arm currents of B, C, Y, and Z I SAMPLE The sampling method and the spatial distribution characteristics of the two sets of windings of the dual three-phase motor with a phase shift angle of 30° are used to combine the carrier phase shift with AZSPWM to construct the reconstruction area, and the six-phase current reconstruction expression of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30° in each reconstruction area is constructed; According to the reconstruction area where the reference voltage vector is located and the real-time acquisition of I SAMPLE , select the corresponding six-phase current reconstruction expression and reconstruct the six-phase current; The dual three-phase permanent magnet synchronous motor with a 30° phase shift angle is controlled according to the reconstructed six-phase current.

2. The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to claim 1 is characterized in that: Methods for constructing reconstruction regions include: Two groups of three-phase SVM strategies are used to plan the voltage space. According to the spatial distribution characteristics of the two sets of windings of the 30° phase shift angle dual three-phase permanent magnet synchronous motor, combined with the three-phase independent modulation idea, the switching vector with 64 degrees of freedom is simplified into two groups of adjacent six-sector vector combinations: Where U dc is the bus voltage; S A , S B , S C , S X , S Y , S Z are the switching functions of the six-phase bridge arms, respectively. A value of 0 represents that the lower tube of the bridge arm is turned on, and a value of 1 represents that the upper tube of the bridge arm is turned on; U 1k is the space vector formed by the first set of three-phase windings ABC; U 2k The space vector formed by the second three-phase winding XYZ, k = 0, 1, 2, 3, 4, 5, 6, 7; When S A =0, S B =0, S C =0 when the corresponding voltage vector U 10 ; When S A =1, S B =0, S C =0 when the corresponding voltage vector U 11 ; When S A =1, S B =1, S C =0 when the corresponding voltage vector U 12 ; When S A =0, S B =1, S C =0 when the corresponding voltage vector U 13 ; When S A =0, S B =1, S C =1 corresponds to the voltage vector U 14 ; When S A =0, S B =0, S C =1 corresponds to the voltage vector U 15 ; When S A =1, S B =0, S C =1 corresponds to the voltage vector U 16 ; When S A =1, S B =1, S C =1 corresponds to the voltage vector U 17 ; When S X =0, S Y =0, S Z =0 when the corresponding voltage vector U 20 ; When S X =1, S Y =0, S Z =0 when the corresponding voltage vector U 21 ; When S X =1, S Y =1, S Z =0 when the corresponding voltage vector U 22 ; When S X =0, S Y =1, S Z =0 when the corresponding voltage vector U 23 ; When S X =0, S Y =1, S Z =1 corresponds to the voltage vector U 24 ; When S X =0, S Y =0, S Z =1 corresponds to the voltage vector U 25 ; When S X =1, S Y =0, S Z =1 corresponds to the voltage vector U 26 ; When S X =1, S Y =1, S Z =1 corresponds to the voltage vector U 27 ; The two sets of three-phase winding space vectors are integrated into the same phase space plane, and 12 groups of reconstructed regions in the phase space are obtained after simplification: The reconstructed region G1 is composed of the space vector U 11 with U 21 Surrounded by The reconstructed region G2 is composed of the space vector U 12 with U 21 Surrounded by The reconstructed region G3 is composed of the space vector U 12 with U 22 Surrounded by The reconstructed region G4 is composed of the space vector U 13 with U 22 Surrounded by The reconstruction region G5 is composed of the space vector U 13 with U 23 Surrounded by The reconstruction region G6 is composed of the space vector U 14 with U 23 Surrounded by The reconstruction region G7 is composed of the space vector U 14 with U 24 Surrounded by The reconstruction region G8 is composed of the space vector U 15 with U 24 Surrounded by The reconstruction region G9 is composed of the space vector U 15 with U 25 Surrounded by The reconstruction region G10 is composed of the space vector U 16 with U 25 Surrounded by The reconstruction region G11 is composed of the space vector U 16 with U 26 Surrounded by The reconstruction region G12 is composed of the space vector U 11 with U 26 Surrounded.

3. The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to claim 2 is characterized in that: The six-phase current reconstruction expression of the dual three-phase permanent magnet synchronous motor with a 30° phase shift angle in each reconstruction area is constructed as follows: Among them, U 1i U 2j Indicates the switch combinations corresponding to two sets of three-phase windings, i=0,1,2,3,4,5,6,7, j=0,1,2,3,4,5,6,7; I1, I2, I3, and I4 represent the currents sampled by the four sampling vector combinations respectively; i A It represents the current of phase A in the first three-phase winding ABC; i B It represents the current of phase B in the first three-phase winding ABC; i C It represents the current of phase C in the first three-phase winding ABC; i X It represents the current of phase X in the second three-phase winding XYZ; i Y Indicates the current of the Y phase in the second three-phase winding XYZ i Z Represents the current of phase Z in the second set of three-phase winding XYZ.

4. The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to claim 3 is characterized in that: When controlling the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30° according to the reconstructed six-phase current, the reconstructed hybrid pulse width modulation RHPWM is used for modulation, including: CPS-PWM is used in all reconstruction areas, and the carrier phase of the second three-phase winding XYZ is delayed by T s / 4, T s Indicates the carrier period; The reference voltage vector is modulated using AZSPWM in the reconstruction areas G1, G2, G6, G7, G8, and G12; The reference voltage vector is modulated using SVPWM when reconstructing areas G3, G4, G5, G9, G10, and G11.

5. The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to claim 1 is characterized in that: The method for controlling a 30° phase-shifted dual three-phase permanent magnet synchronous motor according to the reconstructed six-phase current includes: According to the working condition of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30°, the initial position angle θ0 of the motor is subjected to resolver compensation to obtain the actual speed after resolver compensation; The difference between the motor given speed and the actual speed after resolver compensation is sent to the speed controller ASR-PI to obtain the motor torque current given value; the reconstructed six-phase current is transformed by VSD coordinates to obtain the motor current feedback value, including the torque current feedback value i q , flux current feedback value i d , mutually orthogonal harmonic current feedback values ​​i Z1 、i Z2 ; The difference between the motor torque current set value and the motor current feedback value is sent to the current loop controller ACR-PI, and then the voltage set values ​​of the two sets of three-phase windings are obtained, including the torque voltage set value u q , flux voltage given value u d , mutually orthogonal harmonic voltage given value u z1 、u z2 ; The obtained voltage given value is converted into two sets of three-phase SVM given values, and then reconstructed hybrid pulse width modulation RHPWM is performed to generate driving signals for two sets of three-phase windings to complete the drive control.

6. The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to claim 5 is characterized in that: Methods for resolver compensation include: Calculate the back electromotive force e of the two sets of three-phase windings output by the current loop controller ACR-PI on the d axis respectively d1 、e d2 , and sum e ds-err : In the formula, K i1 , K i2 is the proportional coefficient of the current loop controller ACR-PI, is the d-axis current calibration value of the two sets of three-phase windings, i d1 、i d2 is the actual current value of the d-axis of the two sets of three-phase windings, and dt is the integral calculation period; According to the back electromotive force e of the two sets of three-phase windings d1 、e d2 , adjust the initial position angle θ0 of the motor accordingly, so that the error and e ds-err When the minimum value is reached, the compensated position angle θ is saved, and the actual speed after resolver compensation is obtained according to the position angle θ.

7. The 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to claim 5 is characterized in that: Perform VSD-2DQ equivalent transformation on the voltage given value to obtain two sets of three-phase SVM given values ​​u d1 、u q1 、u d2 、u q2 : Wherein, θ represents the electrical angle of the dual three-phase permanent magnet synchronous motor with a phase shift angle of 30°.

8. A computer-readable storage device storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the 30° phase shift angle dual three-phase permanent magnet synchronous motor control method as claimed in any one of claims 1 to 7 are implemented.

9. A 30° phase shift angle dual three-phase permanent magnet synchronous motor control device, comprising a storage device, a processor, and a computer program stored in the storage device and executable on the processor, characterized in that: The processor executes the computer program to implement the steps of the 30° phase shift angle dual three-phase permanent magnet synchronous motor control method according to any one of claims 1 to 7.

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 30° phase shift angle dual three-phase permanent magnet synchronous motor control method as claimed in any one of claims 1 to 7 are implemented.

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