Bearingless electro-magnetic doubly salient motor with improved integrated winding structure

Abstract

The embodiment of the invention discloses a bearingless electro-magnetic doubly salient motor with an improved integrated winding structure, and relates to the technical field of bearingless motors. A suspension winding and an excitation winding of a traditional bearingless electro-magnetic doubly salient motor are integrated into an integrated suspension winding, and a control method capable of realizing power generation operation and stable suspension of the integrated winding configured bearingless electro-magnetic doubly salient motor is provided. The control method comprises a displacement control module, a suspension excitation current calculation module and a suspension excitation current control module, and stable suspension of the rotor can be realized by controlling the suspension excitation winding current. According to the scheme, winding arrangement is optimized, mutual scheduling of the power generation capacity and the suspension capacity is achieved through equivalent control, and compared with a traditional bearingless doubly salient motor, the bearingless electro-magnetic doubly salient motor with the integrated winding configuration has the advantages that the utilization rate of the groove space is increased, the working range of the bearingless doubly salient motor is widened, and the application range of the bearingless doubly salient motor is widened. And the overall working state is more flexible.

Description

Technical Field

[0001] The invention relates to the technical field of bearingless electrically excited double-pole motors, and in particular to a bearingless electrically excited double-pole motor with an improved integrated winding structure. Background Art

[0002] The stator and rotor of the electrically excited double-salient-pole motor are both salient-pole structures. The excitation magnetic field of the motor is provided by the DC excitation current. No controllable rectifier device and angle position sensor are required during the power generation operation. Therefore, the structure is simple, strong and easy to maintain, and it has good adaptability to high-temperature environment and high-speed operation. In order to avoid the heating and wear of the mechanical bearings of the motor under high-speed operation, magnetic bearings are gradually used as a replacement, which can enable the motor to maintain normal operation without contact between the stator and the rotor. However, in order to achieve stable suspension rotation, the magnetic bearing motor requires more power devices, which is difficult to control and has a complex structure, high cost and low power density. The bearingless motor is a new type of motor that integrates the magnetic bearing function with the drive or power generation function, and has the characteristics of compact structure and high space utilization. For example, the current electromagnetic bearingless double-salient-pole motor and its control method, the excitation magnetic field generated by the excitation winding and the suspension magnetic field generated by the suspension winding are superimposed, resulting in different air gap magnetic density on both sides of the stator, thereby achieving stable suspension of the rotor.

[0003] The excitation magnetic field generated by the excitation winding of the motor and the suspension magnetic field generated by the suspension winding are superimposed, resulting in different air gap magnetic density on both sides of the stator, thereby achieving stable suspension of the rotor. After the motor is in a stable operating state, only a small suspension current needs to be passed through the suspension winding to offset the gravity of the rotor, thereby maintaining stable suspension of the rotor. At this time, the suspension winding only outputs a small suspension force and cannot output power to the outside, so there is a waste of winding resource configuration. In the traditional bearingless electrically excited double-pole motor, the excitation winding and the two sets of suspension windings need to be controlled separately, and once the winding structure of the motor is determined, the suspension winding and the excitation winding cannot be reconfigured, and the two cannot be more rationally configured and adjusted and flexibly converted and scheduled, which limits the power generation capacity and suspension force output capacity of the motor to a certain extent. This leads to the existing bearingless electrically excited double-pole motor solution, where the two sets of windings, the excitation winding and the suspension winding, need to be controlled separately, and once the motor winding structure is determined, the excitation winding and the suspension winding cannot be flexibly converted and scheduled, which limits the power generation capacity and suspension force output capacity of the motor.

[0004] Therefore, how to further integrate and optimize the suspension winding and the excitation winding has become a topic that needs to be studied. Summary of the invention

[0005] An embodiment of the present invention provides a bearingless electrically excited double-salient pole motor with an improved integrated winding structure, which can broaden the operating range of the bearingless double-salient pole motor.

[0006] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a bearingless electrically excited double-salient-pole motor with an improved integrated winding structure, comprising: a rotor core, a stator core, an armature winding and a suspension winding, wherein the suspension winding comprises: Figure 1 The 1# suspension winding W shown sf1 、2# suspension winding W sf2 、3# suspension winding W sf3 and 4# suspension winding W sf4 ;

[0008] The armature coils wound on the stator poles are connected according to the same principle of the change of the turn-link magnetic flux, and form the armature winding W. m ;

[0009] The armature coils of the same phase are connected in series in sequence to form the armature winding of the corresponding phase. Each phase armature winding has two terminals and is connected to the external control circuit as shown in FIG5(a) through the two terminals.

[0010] A set of radial suspension windings is embedded on every three stator poles. The current of each set of suspension windings is controlled separately. Each set of suspension windings is connected to a separate control circuit, and the sets of suspension windings do not interfere with each other. If the current is set to flow into the first terminal of the suspension winding and out of the second terminal as the current reference positive direction, the equivalent magnetic poles formed on the outside of the rotor core are arranged in NSNS along the clockwise direction. According to the right-hand screw rule, the winding arrangement is designed and the current in the specified direction is passed so that the equivalent magnetic poles formed by the four windings on the outside of the rotor core are arranged in NSNS along the clockwise direction. Furthermore, 1# suspension winding W sf1 Winding in slot ① and slot ②, winding in slot ① and out of slot ②, winding stator pole A1, stator pole B1, stator pole C1 around W sf1 Internal; 2# suspension winding W sf2 Winding in slots ① and ③, winding in slot ③ and out of slot ①, winding stator pole A2, stator pole B2, stator pole C2 around W sf2 Internal; 3# suspension winding W sf3 Winding in slots ③ and ④, winding in slot ③ and out of slot ④, winding stator pole A3, stator pole B3, stator pole C3 around W sf3 Internal; 4# suspension winding W sf4 Winding in slots ② and ④, winding in slot ② and out of slot ④, winding stator pole A4, stator pole B4, stator pole C4 around W sf4 internal.

[0011] In the preferred embodiment, the bearingless electrically excited double salient pole motor adopts a 12 / 8 pole double salient pole structure; wherein the rotor core is a salient pole structure, composed of slotted core laminations, with a total of 8 rotor poles; the stator core is also a salient pole structure, with a total of 12 stator poles, and the gaps between adjacent stator poles form stator slots; the suspension winding W sf There are 4 groups in total. Each stator pole is wound with an axial armature coil N m And three adjacent stator poles are combined into one group, with a total of 4 groups of armature coils N m , where each group of three armature coils N m The armature coils N of the same phase in each group belong to phase A, phase B and phase C respectively. m The armature winding W that makes up this phase m .

[0012] FIG5(a) is a schematic diagram of an external rectifier circuit of a bearingless electrically excited double-pole motor with an integrated winding configuration according to an embodiment of the present invention, in which a full-bridge uncontrolled rectifier circuit is used to rectify the alternating current generated on the three-phase armature winding: the first rectifier diode D1 and the second rectifier diode D2 are connected in series, the third rectifier diode D3 and the fourth rectifier diode D4 are connected in series, the fifth rectifier diode D5 and the sixth rectifier diode D6 are connected in series, the cathodes of the first rectifier diode D1, the third rectifier diode D3 and the fifth rectifier diode D5 are connected in series, and the anodes of the second rectifier diode D2, the fourth rectifier diode D4 and the sixth rectifier diode D6 are connected in series. mA , L mB , L mC The input connection of the three-phase armature winding, L mA , L mB , L mC The output ends of the three-phase windings are respectively connected to the anode of the first rectifier diode D1, the anode of the second rectifier diode D2, and the anode of the third rectifier diode D3. After the capacitor C and the resistor R are connected in parallel, their two ends are respectively connected to the common cathode and common anode of the diodes.

[0013] The four sets of suspension windings are connected to control circuits respectively, including: the first set of suspension winding control circuits, including: the first MOS switch tube Q1 and the second MOS tube Q2 are connected in series, the third MOS tube Q3 and the fourth MOS tube Q4 are connected in series, the drain of the first MOS switch tube Q1 and the drain of the third MOS switch tube Q3 are connected to the positive electrode of the DC voltage source Us, the source of the second MOS switch tube Q2 and the source of the fourth MOS switch tube Q4 are connected to the negative electrode of the DC voltage source Us, the suspension winding W sf1The two ends of Lsf1 and resistor R1 are equivalent to being connected to the source of the first MOS switch tube Q1 and the source of the third MOS tube Q3, and the electrolytic capacitor C1 is connected in parallel to the two ends of the voltage source Us; the control circuit of the second set of suspension windings includes: the fifth MOS switch tube Q5 and the sixth MOS tube Q6 are connected in series, the seventh MOS tube Q7 and the eighth MOS tube Q8 are connected in series, the drain of the fifth MOS switch tube Q5 and the drain of the seventh MOS switch tube Q7 are connected to the positive electrode of the DC voltage source Us, the source of the sixth MOS switch tube Q6 and the source of the eighth MOS switch tube Q8 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf2 The two ends of Lsf2 and resistor R2 are equivalent to being connected to the source of the fifth MOS switch tube Q5 and the source of the seventh MOS switch tube Q7, and the electrolytic capacitor C2 is connected in parallel to the two ends of the voltage source Us; the control circuit of the third set of suspension windings includes: the ninth MOS switch tube Q9 and the tenth MOS switch tube Q10 are connected in series, the eleventh MOS switch tube Q11 and the twelfth MOS switch tube Q12 are connected in series, the drain of the ninth MOS switch tube Q9 and the drain of the eleventh MOS switch tube Q11 are connected to the positive electrode of the DC voltage source Us, the source of the tenth MOS switch tube Q10 and the source of the twelfth MOS switch tube Q12 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf3 The two ends of Lsf3 and resistor R3 are equivalent to being connected to the source of the ninth MOS switch tube Q9 and the source of the eleventh MOS switch tube Q11, and the electrolytic capacitor C3 is connected in parallel to the two ends of the voltage source Us. The fourth set of control circuits for suspension windings includes: the thirteenth MOS switch tube Q13 and the fourteenth MOS switch tube Q14 are connected in series, the fifteenth MOS switch tube Q15 and the sixteenth MOS switch tube Q16 are connected in series, the drain of the thirteenth MOS switch tube Q13 and the drain of the fifteenth MOS switch tube Q3 are connected to the positive electrode of the DC voltage source Us, the source of the fourteenth MOS switch tube Q14 and the source of the sixteenth MOS switch tube Q16 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W sf4 Lsf4 and two ends of the resistor R4 are equivalent to being connected to the source of the thirteenth MOS switch tube Q13 and the source of the fifteenth MOS tube Q15 respectively, and the electrolytic capacitor C4 is connected in parallel to the two ends of the voltage source Us.

[0014] In a second aspect, an embodiment of the present invention provides a control method, comprising: a displacement control module, a suspension current calculation module and a suspension current control module;

[0015] In the displacement control module, obtaining suspension current reference values ​​in the X direction and the Y direction;

[0016] In the suspension current calculation module, based on the suspension current reference values ​​in the X direction and the Y direction, the given values ​​of the suspension current in the suspension windings in the X direction and the Y direction are obtained;

[0017] In the suspension current control module, the difference between the actual current value of each suspension winding and the given value of the suspension current of each suspension winding obtained in the suspension current calculation link is input into the PI link corresponding to each suspension winding;

[0018] The four PWM signals output by the suspension current control module are respectively input into corresponding modules, wherein the four suspension current control modules respectively control the opening and closing of their respective switch tubes according to their respective PWM signals to achieve the tracking of the suspension current to its reference value.

[0019] The displacement control includes: using an eddy current sensor to obtain the current position x of the rotor and the reference value x of the rotor position. * After the difference is made, the required suspension force F in the X-axis direction is obtained after adjustment by the X-direction displacement PID control module. x * The rotor position angle, armature current and suspension current obtained by sampling are transformed into the suspension current reference value i after coordinate transformation. sx * ; Use the eddy current sensor to obtain the current rotor position y and the rotor position reference value y * After the difference is made, the Y-direction displacement PID control module adjusts the required suspension force F in the Y-axis direction. y * The rotor position angle, armature current and suspension current obtained by sampling are transformed into the suspension current reference value after coordinate transformation. sy * .

[0020] Suspension current calculation includes: taking the required suspension current reference value i in the Y-axis direction sy * The reference value of the excitation current required under this condition is i f * After adding, we get 1# suspension winding W sf1 The current flowing through is the given value of the suspension current i sf1 * ; Set the required suspension current reference value i in the X-axis direction sx * The reference value of the excitation current required under this condition is i f * After adding, we get 2# suspension winding W sf2 The current flowing through is the given value of the suspension current i sf2 * ; Set the required suspension current reference value i in the Y-axis direction sy * The reference value of the excitation current required under this condition is i f *After subtracting, we get 3# suspension winding W sf3 The current flowing through is the given value of the suspension current i sf3 * ; Set the required suspension current reference value i in the X-axis direction sx * The reference value of the excitation current required under this condition is i f * After subtracting, we get 4# suspension winding W sf4 The current flowing through is the given value of the suspension current i sf4 * .

[0021] Suspension current control includes: sf1 The actual current i passing through sf1 The corresponding given value of suspension excitation current i sf1 * The difference value is input into the corresponding PI link, and the 2# suspension winding W sf2 The actual current i passing through sf2 The corresponding given value of suspension excitation current i sf2 * The difference value is input into the corresponding PI link, and the 3# suspension winding W sf3 The actual current i passing through sf3 The corresponding given value of suspension excitation current i sf3 * The difference value is input into the corresponding PI link, and the 4# suspension winding W sf4 The actual current i passing through sf4 The corresponding given value of suspension excitation current i sf4 * The difference value is input into the corresponding PI link. The suspension current control module includes: in the displacement control module, four sets of eddy current sensors are used to obtain the rotor position signal by measuring the distance between the probe and the shaft reference ring; in the suspension current control part, four sets of current Hall sensors are used to measure the current flowing through the four sets of suspension windings respectively.

[0022] The bearingless electrically excited double salient pole motor with improved integrated winding structure provided by the embodiment of the present invention is based on the original bearingless electrically excited double salient pole motor, and the suspension winding and the excitation winding are modified to integrate into a set of suspension windings. Compared with the traditional bearingless double salient pole motor, the integrated winding bearingless electrically excited double salient pole motor designed by the present invention improves the utilization rate of the slot space, broadens the working range of the bearingless double salient pole motor, and the overall working state is more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 The overall structure diagram of the bearingless electrically excited double-salient-pole motor with integrated winding configuration according to an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of the structure and winding arrangement of a bearingless electrically excited double-salient-pole motor with an integrated winding configuration according to an embodiment of the present invention;

[0026] Figure 3 An equivalent magnetic circuit diagram of a bearingless electrically excited double-salient-pole motor configured with an integrated winding according to an embodiment of the present invention;

[0027] Figure 4 A schematic diagram of electromagnetic force generated by each stator pole of a bearingless electrically excited double-salient-pole motor with an integrated winding configuration according to an embodiment of the present invention;

[0028] Figure 5(a) to Figure 5(e) Schematic diagrams of an external rectifier circuit and four sets of suspension winding control circuits of a bearingless electrically excited double-pole motor configured with an integrated winding according to an embodiment of the present invention;

[0029] Figure 6 The present invention is a driving control flow chart of a bearingless electrically excited double-salient pole motor that can provide power output and suspension force according to an embodiment of the present invention.

[0030] Figure 7 The comparison chart of the operating range of the bearingless electrically excited double-pole motor (IWBDSEM) with integrated winding configuration under equivalent control and the bearingless electrically excited double-pole motor (BDSEM) with variable conventional excitation winding and suspension winding is shown in the comparison chart: ω=4000r / min, R load =2Ω. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention. It can be understood by those skilled in the art that, unless specifically stated, the singular forms "one", "one", "said" and "the" used herein may also include plural forms. It should be further understood that the term "including" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or their groups. It should be understood that when we say that an element is "connected" or "coupled" to another element, it can be directly connected or coupled to other elements, or there may also be intermediate elements. In addition, the "connection" or "coupling" used here may include wireless connection or coupling. The term "and / or" used herein includes any unit and all combinations of one or more associated listed items. It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as generally understood by those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0032] The main structural features of the electromagnetic bearingless double-salient-pole motor designed in this embodiment are as follows: Figure 1 The three-phase 12 / 8 structure electromagnetic bearingless double-salient pole motor shown is only one embodiment of the present invention. The technical solution of the present invention is also applicable to a 12n / 4n three-phase structure or a 16n / 6n four-phase structure, where n is a positive integer.

[0033] Figure 2 The structure and winding arrangement diagram of the bearingless electrically excited double-pole motor with integrated winding configuration of the present invention are shown. The bearingless electrically excited double-pole motor with integrated winding configuration adopts a 12 / 8-pole double-pole structure with higher power density among the double-pole structures with matched pole slots under current research theory, including: a rotor core, a stator core, an armature winding, and a suspension winding. The rotor core is composed of slot-type core laminations with a total of 8 rotor poles. The stator core is also a salient pole structure with a total of 12 stator poles. The gaps between adjacent stator poles form stator slots. In addition, in this embodiment, "winding" is uniformly identified as "W", such as the armature winding "W m"; and "coil" is uniformly marked as "N", such as armature coil "N m " to distinguish.

[0034] Figure 2 The structure and winding arrangement diagram of the bearingless electric excitation double salient pole motor with integrated winding configuration according to the embodiment of the present invention is shown in FIG. 1 . The armature coils wound on the stator poles are arranged according to the same principle of the change law of the turn-link magnetic flux. The armature coils of the same phase are arranged according to Figure 2 The wiring method shown in the figure is connected in series to form the armature winding of the phase. In the three-phase armature winding, each phase has two terminals and is connected to the external control circuit through the two terminals. There are six terminals in total for the three phases. An armature coil N is wound on each stator pole. m , and three adjacent stator poles are combined into one group, with a total of 4 groups. The first terminal A+ of the A-phase armature winding and the second terminal A- of the A-phase armature winding are connected to the external control circuit. Similarly, the first terminal B+ of the B-phase armature winding and the second terminal B- of the B-phase armature winding are connected to the external control circuit; the first terminal C+ of the C-phase armature winding and the second terminal C- of the C-phase armature winding are connected to the external control circuit. A set of radial suspension windings is embedded on every three stator poles, and the current thereon is controlled separately. Each set of suspension windings does not interfere with each other. There are a total of 4 groups, and each set of suspension windings is wound in the same way. If the current is specified to flow in from the first terminal of the suspension winding and out from the second terminal as the current reference positive direction, the equivalent magnetic poles formed on the outside of the rotor core are arranged in NSNS along the clockwise direction. Among them, the 1# suspension winding W sf1 Winding in slot ① and slot ②, winding in slot ① and out of slot ②, winding stator pole A1, stator pole B1, stator pole C1 around W sf1 Internal; 2# suspension winding W sf2 Winding in slots ① and ③, winding in slot ③ and out of slot ①, winding stator pole A2, stator pole B2, stator pole C2 around W sf2 Internal; 3# suspension winding W sf3 Winding in slots ③ and ④, winding in slot ③ and out of slot ④, winding stator pole A3, stator pole B3, stator pole C3 around W sf3 Internal; 4# suspension winding W sf4 Winding in slots ② and ④, winding in slot ② and out of slot ④, winding stator pole A4, stator pole B4, stator pole C4 around W sf4 internal.

[0035] Figure 3 : is the equivalent magnetic circuit diagram of the bearingless electrically excited double-salient-pole motor with integrated winding according to the embodiment of the present invention. mA 、i mB 、i mCare the current values ​​flowing through the three-phase armature windings A, B, and C respectively. sf1 、i sf2 、i sf3 、i sf4 are the currents flowing through the four suspension windings, right, top, left, and bottom. m is the number of turns of the armature winding, N sf is the number of turns of the four suspension windings. Without considering the influence of nonlinear factors such as core magnetic saturation and leakage magnetic flux, the equations of the equivalent magnetic circuit can be written out according to the equivalent magnetic circuit diagram, as shown in formula (1):

[0036]

[0037] Let the outer side of the rotor be the zero magnetic potential plane. M1, M2, M3, and M4 in the above formula are the magnetic potentials of the four nodes, and are independent of the rotor position angle. The solution is shown in formula (2):

[0038]

[0039] The calculated magnetic flux density under each stator pole is shown in the following formula (3), where j is A or B or C, μ0 is the vacuum permeability, and L gap is the air gap length:

[0040]

[0041] Figure 4 The electromagnetic force vector F generated by each stator pole of the bearingless electric excitation double-salient motor with integrated winding configuration according to the embodiment of the present invention is taken as an example when the rotor angle is between 0 and 15° and the A and B phases coincide during operation. jk The direction is considered to be from the center of the rotor to the center of the stator pole, k is the number of 1 to 4 groups of stator poles, and the magnitude of the electromagnetic force generated by each stator pole on the rotor can be calculated by the Maxwell stress method:

[0042]

[0043] Among them, S j is the overlapping area between the j-phase stator pole and the rotor pole, as shown in formula (5):

[0044]

[0045] The calculation results are shown in formula (6):

[0046]

[0047] Among them, F A1-3 Indicates F A1 With F A3 The magnitude of the resultant force, FA2-4 Indicates F A2 With F A4 The magnitude of the resultant force, F B1-3 Refers to F B1 With F B3 The magnitude of the resultant force, F B2-4 Refers to F B2 With F B4 The magnitude of the resultant force. F x and F y are the components of the suspension force vector F acting on the rotor in the X-axis direction and the Y-axis direction, as shown in formula (7):

[0048]

[0049] Substituting equation (6) into equation (7), the components of the suspension force vector F acting on the rotor in the X-axis direction and the Y-axis direction can be obtained through calculation. The calculation results are shown in equation (8):

[0050]

[0051] FIG5(a) is a schematic diagram of an external rectifier circuit of a bearingless electrically excited double-pole motor with an integrated winding configuration according to an embodiment of the present invention, in which a full-bridge uncontrolled rectifier circuit is used to rectify the alternating current generated on the three-phase armature winding: the first rectifier diode D1 and the second rectifier diode D2 are connected in series, the third rectifier diode D3 and the fourth rectifier diode D4 are connected in series, the fifth rectifier diode D5 and the sixth rectifier diode D6 are connected in series, the cathodes of the first rectifier diode D1, the third rectifier diode D3 and the fifth rectifier diode D5 are connected in series, and the anodes of the second rectifier diode D2, the fourth rectifier diode D4 and the sixth rectifier diode D6 are connected in series. mA , L mB , L mC The input connection of the three-phase armature winding, L mA , L mB , L mC The output ends of the three-phase windings are respectively connected to the anode of the first rectifier diode D1, the anode of the second rectifier diode D2, and the anode of the third rectifier diode D3. After the capacitor C and the resistor R are connected in parallel, their two ends are respectively connected to the common cathode and common anode of the diodes.

[0052] FIG5(b) is a schematic diagram of a control circuit of a first set of suspension windings, wherein a first MOS switch tube Q1 and a second MOS switch tube Q2 are connected in series, a third MOS switch tube Q3 and a fourth MOS switch tube Q4 are connected in series, a drain of the first MOS switch tube Q1 and a drain of the third MOS switch tube Q3 are connected to the positive electrode of a DC voltage source Us, a source of the second MOS switch tube Q2 and a source of the fourth MOS switch tube Q4 are connected to the negative electrode of the DC voltage source Us, and a suspension winding W is connected to the first MOS switch tube Q1 and a second MOS switch tube Q2 and a third MOS switch tube Q4. sf1Lsf1 and resistor R1 are equivalent to being connected to the source of the first MOS switch tube Q1 and the source of the third MOS tube Q3, and the electrolytic capacitor C1 is connected in parallel to both ends of the voltage source Us.

[0053] FIG5(c) is a schematic diagram of a control circuit of a second set of suspension windings, wherein the fifth MOS switch tube Q5 and the sixth MOS switch tube Q6 are connected in series, the seventh MOS switch tube Q7 and the eighth MOS switch tube Q8 are connected in series, the drain of the fifth MOS switch tube Q5 and the drain of the seventh MOS switch tube Q7 are connected to the positive electrode of the DC voltage source Us, the source of the sixth MOS switch tube Q6 and the source of the eighth MOS switch tube Q8 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf2 Lsf2 and resistor R2 are equivalent to being connected to the source of the fifth MOS switch tube Q5 and the source of the seventh MOS tube Q7, and the electrolytic capacitor C2 is connected in parallel to both ends of the voltage source Us.

[0054] FIG5(d) is a schematic diagram of a control circuit of a third set of suspension windings, wherein the ninth MOS switch tube Q9 and the tenth MOS switch tube Q10 are connected in series, the eleventh MOS switch tube Q11 and the twelfth MOS switch tube Q12 are connected in series, the drain of the ninth MOS switch tube Q9 and the drain of the eleventh MOS switch tube Q11 are connected to the positive electrode of the DC voltage source Us, the source of the tenth MOS switch tube Q10 and the source of the twelfth MOS switch tube Q12 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf3 Lsf3 and resistor R3 are equivalent to being connected to the source of the ninth MOS switch tube Q9 and the source of the eleventh MOS tube Q11, and the electrolytic capacitor C3 is connected in parallel to both ends of the voltage source Us.

[0055] FIG5(e) is a schematic diagram of a control circuit of a fourth set of suspension windings, wherein the thirteenth MOS switch tube Q13 and the fourteenth MOS switch tube Q14 are connected in series, the fifteenth MOS switch tube Q15 and the sixteenth MOS switch tube Q16 are connected in series, the drain of the thirteenth MOS switch tube Q13 and the drain of the fifteenth MOS switch tube Q3 are connected to the positive electrode of the DC voltage source Us, the source of the fourteenth MOS switch tube Q14 and the source of the sixteenth MOS switch tube Q16 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf4 Lsf4 and resistor R4 are equivalent to being connected at both ends to the source of the thirteenth MOS switch tube Q13 and the source of the fifteenth MOS tube Q15 respectively, and the electrolytic capacitor C4 is connected in parallel to the two ends of the voltage source Us.

[0056] Figure 6The present invention provides a driving control flow chart of a bearingless electrically excited double-pole motor with power output and suspension force. The control method of a bearingless electrically excited double-pole motor with an integrated winding configuration is characterized in that the method includes a displacement control module, a suspension current calculation module and a suspension current control module. The control steps are as follows: In the displacement control module, an eddy current sensor is used to obtain the current position x of the rotor and the rotor position reference value x * After the difference is made, the required suspension force F in the X-axis direction is obtained after adjustment by the X-direction displacement PID controller. x * , F x * The rotor position angle, armature current and suspension current obtained by sampling are transformed into the suspension current reference value i after coordinate transformation. sx * ; Use the eddy current sensor to obtain the current rotor position y and the rotor position reference value y * After the difference is made, the Y-direction displacement PID controller is used to adjust the required suspension force F in the Y-axis direction. y * , F y * The rotor position angle, armature current and suspension current obtained by sampling are transformed into the suspension current reference value after coordinate transformation. sy * . Set the required suspension current reference value i in the Y-axis direction sy * The reference value of the excitation current required under this condition is i f * After adding, we get the current flowing in the 1# suspension winding, which is the given value of the suspension current i. sf1 * ; Set the required suspension current reference value i in the X-axis direction sx * The reference value of the excitation current required under this condition is i f * After adding, we get the current flowing in the 2# suspension winding, which is the given value of the suspension current i. sf2 * ; Set the required suspension current reference value i in the Y-axis direction sy * The reference value of the excitation current required under this condition is i f * After the difference is made, the current flowing through the 3# suspension winding is obtained, which is the given value of the suspension current i. sf3 * ; Set the required suspension current reference value i in the X-axis direction sx * The reference value of the excitation current required under this condition is i f* After the difference is made, the current flowing through the 4# suspension winding is obtained, which is the given value of the suspension current i. sf4 * In the suspension current control module, the actual current i passing through the 1# suspension winding is sf1 The corresponding given value of suspension excitation current i sf1 * The difference value is input into the corresponding PI link, and the actual current i passing through the 2# suspension winding is sf2 The corresponding given value of suspension excitation current i sf2 * The difference value is input into the corresponding PI link, and the actual current i passing through the 3# suspension winding is sf3 The corresponding given value of suspension excitation current i sf3 * The difference value is input into the corresponding PI link, and the actual current i passing through the 4# suspension winding is sf4 The corresponding given value of suspension excitation current i sf4 * The difference value is input into the corresponding PI link. The four PWM signals output by the suspension current control module are respectively input into the corresponding modules, wherein the four suspension current control modules respectively control the opening and closing of their respective switch tubes according to their respective duty cycle signals to achieve the tracking of the suspension current to its reference value.

[0057] Figure 7 Comparison of the operating range of the bearingless electrically excited doubly salient pole motor (IWBDSEM) with integrated winding configuration and the bearingless electrically excited doubly salient pole motor (BDSEM) with variable conventional excitation winding and suspension winding under equivalent control (ω=4000r / min,R load =2Ω). When the ratio of the number of turns of the suspension coil and the excitation coil is changed, the excitation magnetic potential of the same size is replaced by the suspension magnetic potential, and the relationship between the power generation and the suspension force under different ratios of the number of turns of the suspension coil and the excitation coil is explored. When the ratio of the number of turns of the suspension coil and the excitation coil is 10 / 90, its working range is Figure 7 ①, ②, ③; when the ratio of the number of turns of the suspension coil and the excitation coil is 30 / 70, its working range is Figure 7 ①, ②, ④, ⑤ in the figure; when the ratio of the turns of the suspension coil and the excitation coil is 50 / 50, the working range is Figure 7 ①, ④, ⑥ in the figure. The operating range of the bearingless electrically excited double-salient-pole motor with integrated winding configuration under equivalent control is Figure 7The largest envelope area in the rotor covers all the above working ranges, broadening the working range of the bearingless double-salient-pole motor. When the motor needs a larger suspension force output, the suspension current component in the winding can be increased. When the rotor enters a stable suspension state, more excitation current components can be introduced for power generation. Compared with the structure of excitation winding plus suspension winding, this control method eliminates the fixed winding turns distribution, thereby eliminating the problem of unschedulable suspension force and power generation capacity, and improving the slot space utilization and overall working flexibility of the traditional bearingless electrically excited double-salient-pole motor.

[0058] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The above is only a specific implementation method of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or replacements that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A bearingless electrically excited double-salient-pole motor with an improved integrated winding structure, characterized in that: include: Rotor core, stator core, armature winding and suspension winding; The armature coils wound on the stator poles are connected according to the same principle of the change of the turn-link magnetic flux, and form the armature winding W. m ; The armature coils of the same phase are connected in series in sequence to form the armature winding of the corresponding phase. Each phase armature winding has two terminals and is connected to the external control circuit through the two terminals. A set of radial suspension windings is embedded on every three stator poles. The current of each set of suspension windings is controlled separately. Each set of suspension windings is connected to a separate control circuit, and the sets of suspension windings do not interfere with each other.

2. The bearingless electrically excited double-salient pole motor according to claim 1, characterized in that: The bearingless electrically excited double-salient-pole motor adopts a 12 / 8-pole double-salient-pole structure; The rotor core is a salient pole structure, consisting of slot-type core laminations, with a total of 8 rotor poles; The stator core is also a salient pole structure, with a total of 12 stator poles, and the gaps between adjacent stator poles form stator slots; There are 4 groups of suspension windings.

3. The bearingless electrically excited double-salient pole motor according to claim 2, characterized in that: Each stator pole is wound with an axial armature coil N m And three adjacent stator poles are combined into one group, with a total of 4 groups of armature coils N m , where each group of three armature coils N m The armature coils N of the same phase in each group belong to phase A, phase B and phase C respectively. m The armature winding W that makes up this phase m .

4. The bearingless electrically excited double-salient pole motor according to claim 1, characterized in that: The external rectifier circuit uses a full-bridge uncontrolled rectifier circuit to rectify the alternating current generated on the three-phase armature winding, which includes: The first rectifier diode D1 and the second rectifier diode D2 are connected in series, the third rectifier diode D3 and the fourth rectifier diode D4 are connected in series, and the fifth rectifier diode D5 and the sixth rectifier diode D6 are connected in series; The cathodes of the first rectifier diode D1, the third rectifier diode D3 and the fifth rectifier diode D5 are connected, and the anodes of the second rectifier diode D2, the fourth rectifier diode D4 and the sixth rectifier diode D6 are connected; L mA , L mB , L mC The input ends of the three-phase armature windings are connected to each other; L mA , L mB , L mC The output ends of the three-phase windings are respectively connected to the anode of the first rectifier diode D1, the anode of the second rectifier diode D2, and the anode of the third rectifier diode D3. After the capacitor C and the resistor R are connected in parallel, their two ends are respectively connected to the common cathode and common anode of the diodes.

5. The bearingless electrically excited double-salient pole motor according to claim 1, characterized in that: The control circuits connected to the four suspension windings include: The first set of control circuits for the suspension winding includes: a first MOS switch tube Q1 and a second MOS switch tube Q2 are connected in series, a third MOS switch tube Q3 and a fourth MOS switch tube Q4 are connected in series, the drain of the first MOS switch tube Q1 and the drain of the third MOS switch tube Q3 are connected to the positive electrode of the DC voltage source Us, the source of the second MOS switch tube Q2 and the source of the fourth MOS switch tube Q4 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf1 The two ends of Lsf1 and resistor R1 are equivalent to being connected to the source of the first MOS switch tube Q1 and the source of the third MOS tube Q3, and the electrolytic capacitor C1 is connected in parallel to the two ends of the voltage source Us; The second set of control circuits for the suspension winding includes: a fifth MOS switch tube Q5 and a sixth MOS switch tube Q6 are connected in series, a seventh MOS switch tube Q7 and an eighth MOS switch tube Q8 are connected in series, the drain of the fifth MOS switch tube Q5 and the drain of the seventh MOS switch tube Q7 are connected to the positive electrode of the DC voltage source Us, the source of the sixth MOS switch tube Q6 and the source of the eighth MOS switch tube Q8 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the first MOS switch tube Q5 and the second MOS switch tube Q6. sf2 The two ends of Lsf2 and resistor R2 are equivalent to being connected to the source of the fifth MOS switch tube Q5 and the source of the seventh MOS tube Q7, and the electrolytic capacitor C2 is connected in parallel to the two ends of the voltage source Us; The third set of control circuits for the suspension winding includes: a ninth MOS switch tube Q9 and a tenth MOS switch tube Q10 are connected in series, an eleventh MOS switch tube Q11 and a twelfth MOS switch tube Q12 are connected in series, the drain of the ninth MOS switch tube Q9 and the drain of the eleventh MOS switch tube Q11 are connected to the positive electrode of the DC voltage source Us, the source of the tenth MOS switch tube Q10 and the source of the twelfth MOS switch tube Q12 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf3 The equivalent Lsf3 and the two ends of the resistor R3 are connected to the source of the ninth MOS switch tube Q9 and the source of the eleventh MOS tube Q11, and the electrolytic capacitor C3 is connected in parallel to the two ends of the voltage source Us; The fourth set of control circuits for the suspension winding includes: a thirteenth MOS switch tube Q13 and a fourteenth MOS switch tube Q14 are connected in series, a fifteenth MOS switch tube Q15 and a sixteenth MOS switch tube Q16 are connected in series, the drain of the thirteenth MOS switch tube Q13 and the drain of the fifteenth MOS switch tube Q3 are connected to the positive electrode of the DC voltage source Us, the source of the fourteenth MOS switch tube Q14 and the source of the sixteenth MOS switch tube Q16 are connected to the negative electrode of the DC voltage source Us, and the suspension winding W is connected to the positive electrode of the DC voltage source Us. sf4 Lsf4 and two ends of the resistor R4 are equivalent to being connected to the source of the thirteenth MOS switch tube Q13 and the source of the fifteenth MOS tube Q15 respectively, and the electrolytic capacitor C4 is connected in parallel to two ends of the voltage source Us.

6. The bearingless electrically excited double-salient pole motor according to any one of claims 1 to 5, characterized in that: A control method for the bearingless electrically excited double-salient-pole motor, comprising: a displacement control module, a suspension excitation current calculation module and a suspension excitation current control module; In the displacement control module, obtaining suspension current reference values ​​in the X direction and the Y direction; In the suspension current calculation module, based on the suspension current reference values ​​in the X direction and the Y direction, the given values ​​of the suspension current in the suspension windings in the X direction and the Y direction are obtained, wherein the two opposite groups of suspension windings correspond to the same direction; In the suspension current control module, the difference between the actual current value of each suspension winding and the given value of the suspension current of each suspension winding obtained in the suspension current calculation link is input into the PI link corresponding to each suspension winding; The four PWM signals output by the suspension current control module are respectively input into corresponding suspension winding control circuits.

7. The bearingless electrically excited double-salient pole motor according to claim 6, characterized in that: The displacement control module comprises: The eddy current sensor is used to obtain the current position x of the rotor core, and then compared with the rotor position reference value x * The difference is input into the X-direction displacement PID control module, and the X-direction displacement PID control module outputs the required suspension force set value F in the X-axis direction. x * , F x * The rotor position angle, armature current and suspension current obtained by sampling are transformed into the suspension current reference value i sx * ; The eddy current sensor is used to obtain the current position y of the rotor core, and then compared with the rotor position reference value y * The difference is input into the Y-direction displacement PID control module, and the Y-direction displacement PID control module outputs the required suspension force set value F in the Y-axis direction. y * , F y * The rotor position angle, armature current and suspension current obtained by sampling are transformed into the suspension current reference value i sy * .

8. The bearingless electrically excited double-salient pole motor according to claim 6, characterized in that: The suspension current calculation part includes: The required suspension current reference value i in the Y-axis direction * sy The reference value of the excitation current required under this condition is i * f , after adding, we get the suspension winding W sf1 The given current in is used as the given value of the suspension current of the 1# suspension winding i sf1 * ; The required suspension current reference value i in the X-axis direction * sx The reference value of the excitation current required under this condition is i * f After adding, we get the suspension winding W sf2 The given current in is used as the given value of the suspension current of the 2# suspension winding i sf2 * ; The required suspension current reference value i in the Y-axis direction * sy The reference value of the excitation current required under this condition is i * f After subtracting, we get the suspension winding W sf3 The given current in is used as the given value of the suspension current of the 3# suspension winding i sf3 * ; The required suspension current reference value i in the X-axis direction * sx The reference value of the excitation current required under this condition is i * f After subtracting, we get the suspension winding W sf4 The given current in is used as the given value of the 4# suspension winding i sf4 * .

9. The bearingless electrically excited double-salient pole motor according to claim 6, characterized in that: The suspension excitation current control module comprises: Set the 1# suspension winding W sf1 The actual current i passing through sf1 The corresponding given value of suspension excitation current i sf1 * The difference value is input into the PI link corresponding to the 1# suspension winding; Set the 2# suspension winding W sf2 The actual current i passing through sf2 The corresponding given value of suspension excitation current i sf2 * The difference value is input into the PI link corresponding to the 2# suspension winding; Set the 3# suspension winding W sf3 The actual current i passing through sf3 The corresponding given value of suspension excitation current i sf3 * The difference value is input into the PI link corresponding to the 3# suspension winding; Set the 4# suspension winding W sf4 The actual current i passing through sf4 The corresponding given value of suspension excitation current i sf4 * The difference value is input into the PI link corresponding to the 4# suspension winding.

10. The bearingless electrically excited double-salient pole motor according to claim 6, characterized in that: The suspension excitation current control module comprises: In the displacement control module, four sets of eddy current sensors are used to obtain rotor position signals by measuring the distance between the probe and the shaft reference ring; In the suspension current control module, four sets of current Hall sensors are used to measure the currents flowing through the four sets of suspension windings respectively.

Images