Novel parallel hybrid excitation bearingless doubly salient motor

Abstract

The embodiment of the invention discloses a novel parallel hybrid excitation bearingless doubly salient motor, and relates to the technical field of bearingless motors. The side-by-side hybrid excitation bearingless doubly salient motor is composed of two parts of bearingless doubly salient motors which are coaxially arranged in parallel, one part is excited by a stator permanent magnet, the other part is excited by an excitation winding, and magnetic flux paths of the two parts are mutually independent and share one set of armature winding. Due to the fact that the two excitation modes of permanent magnet and electric excitation are adopted at the same time, the power density of the motor is remarkably improved, and the adjustment range needed by suspension current in the excitation current adjustment process is greatly reduced. In addition, when short circuit and other winding faults occur and field suppression is needed, the exciting current is reversed, the suspension force can still be stably generated by adjusting the two parts of current on the suspension winding, and the reliability of suspension operation of the system is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bearingless electrically excited double-pole motors, and in particular to a novel parallel hybrid-excited bearingless double-pole motor. Background Art

[0002] Bearingless motors are a new type of motor that integrates the functions of a magnetic bearing with those of a drive or power generation system. They feature a compact structure and high space efficiency. As a key enabler of active magnetic levitation technology, bearingless motors achieve integrated levitation and motor / power generation by integrating the suspension winding function of the magnetic bearing with the starter generator. This not only effectively frees up axial space but also significantly improves rotor suspension stability by actively controlling the radial electromagnetic force of the motor.

[0003] For traditional bearingless doubly salient motors, their single excitation source limits the ability to increase power generation capacity and power density while maintaining safety requirements. Furthermore, the traditional design uses the excitation winding as both the bias and excitation magnetic field sources, coupling the power generation and suspension design. This makes it difficult to achieve the optimal operating point for high-power-density power generation and high-load suspension. Furthermore, during voltage regulation or demagnetization due to a short-circuit fault, the excitation current fluctuates significantly or even drops to zero, dissipating the bias magnetic field and making it impossible to maintain suspension force, seriously impacting the safe and stable operation of the system.

[0004] Therefore, how to improve the reliability of the suspended operation of the bearingless double-pole motor has become a topic that requires further research and optimization. Summary of the Invention

[0005] An embodiment of the present invention provides a novel parallel hybrid excitation bearingless double-salient-pole motor, which can improve the reliability of the suspension operation of the bearingless double-salient-pole motor.

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

[0007] The main structure of the motor is divided into an electric excitation section and a permanent magnet section; the electric excitation section includes: an electric excitation section stator core, an electric excitation section suspension winding, and an electric excitation section rotor core; the permanent magnet section includes: a permanent magnet section stator core, a permanent magnet section suspension winding, permanent magnets, a permanent magnet section suspension winding, and a permanent magnet section rotor core; the electric excitation section and the permanent magnet section share a set of armature windings, and the excitation winding is located in the electric excitation section; the electric excitation section and the permanent magnet section share a set of armature windings, and the armature coils wound on the stator poles are connected according to the same principle of change of the turn-link magnetic flux to form an armature winding W m ; The permanent magnets are evenly arranged around the stator core and embedded in the stator core yoke.

[0008] Specifically, armature coils are wound around the stator teeth of the stator core of the electromagnetic section and the stator teeth of the stator core of the permanent magnet section, respectively. An axial armature coil N is wound around each stator tooth. m The three adjacent stator poles are grouped together. The three armature coils in each group belong to phase A, phase B and phase C respectively. The armature coils of the same phase are connected in series in sequence to form the armature winding of the phase, and the armature windings W of phase A, phase B and phase C are obtained. mA , W mB and W mC ;Each phase armature winding has two terminals and is connected to the external control circuit through these two terminals.

[0009] Further excitation coils are embedded in the stator poles formed by three stator teeth. Each set of excitation coils is wound in the same way and each set of excitation coils has a first terminal and a second terminal. All excitation coils are connected in series in sequence to form an excitation winding; wherein, the second terminal of the first set of excitation coils is connected in series with the second terminal of the second set of excitation coils in the clockwise direction, the first terminal of the second set of excitation coils is connected in series with the second terminal of the third set of excitation coils in the clockwise direction, and the first terminal of the third set of excitation windings is connected in series with the second terminal of the fourth set of excitation coils in the clockwise direction.

[0010] In the preferred embodiment, both the electromagnetic section and the permanent magnet section adopt a 12 / 8 pole double salient pole structure; wherein, the salient pole structures of the electromagnetic section rotor core and the permanent magnet section rotor core are both composed of slot-type core laminations, and each has 8 rotor poles; the electromagnetic section stator core and the permanent magnet section stator core are also salient pole structures, each with a total of 12 stator poles, and the gaps between adjacent stator poles form stator slots.

[0011] In the preferred embodiment, four permanent magnets of identical size and shape are used; the tangentially magnetized permanent magnets are located in the stator core yoke, and the magnetization directions of two permanent magnets in adjacent stator poles are opposite. The tangentially magnetized permanent magnets located in the stator core yoke can be understood as follows: the line connecting the N-S poles of each permanent magnet is parallel to the motor tangent, and is considered tangential, while the non-N-S pole line points toward the center of the circle.

[0012] Furthermore, the electric excitation section suspension winding includes: the electric excitation section X-axis suspension winding W esx And the Y-axis suspension winding W of the electric excitation section esy Among them, W esx It consists of two sets of suspension coils arranged on the stator poles composed of three stator teeth and radially opposite to each other on the X axis, and is used to control the X-axis suspension of the electro-magnetic rotor. esy It consists of two sets of suspension coils arranged on the stator poles composed of three stator teeth and radially opposite to each other on the Y axis, and is used to control the Y-axis suspension of the electro-magnetic section rotor;

[0013] The permanent magnet segment suspension winding includes: permanent magnet segment X-axis suspension winding W psx and the permanent magnet segment Y-axis suspension winding W psy Among them, W psx It consists of two sets of suspension coils arranged on the stator poles composed of three stator teeth and radially opposite to each other on the X axis, and is used to control the X-axis suspension of the electro-magnetic rotor. psy It consists of two sets of suspension coils arranged on stator poles composed of three stator teeth and radially opposite to each other on the Y axis, and is used to control the Y-axis suspension of the electromagnetic segment rotor.

[0014] W esx Each set of X-axis suspension coils has two terminals. The first terminal of the first set of X-axis suspension coils is used as the electric excitation section X-axis suspension winding W. esx The first output terminal Xe1+, the second terminal of the first set of X-axis suspension coils is connected to the first terminal of the second set of X-axis suspension coils, and the second terminal of the second set of X-axis suspension coils serves as the electric excitation section X-axis suspension winding W. esx The second output terminal Xe1- is connected to the external X-axis suspension control circuit;

[0015] W esy Each set of Y-axis suspension coils has two terminals. The first terminal of the first set of Y-axis suspension coils serves as the Y-axis suspension winding W of the electric excitation section. esy The first output terminal Ye1+, the second terminal of the first set of Y-axis suspension coils is connected to the first terminal of the second set of Y-axis suspension coils, and the second terminal of the second set of Y-axis suspension coils serves as the Y-axis suspension winding W of the electric excitation section. esy The second output terminal Ye1- is connected to the external Y-axis suspension control circuit;

[0016] W psx Each set of X-axis suspension coils has two terminals. The first terminal of the first set of X-axis suspension coils serves as the permanent magnet segment X-axis suspension winding W. psx The first output terminal Xp1+, the second terminal of the first set of X-axis suspension coils are connected to the first terminal of the second set of X-axis suspension coils, and the second terminal of the second set of X-axis suspension coils is used as the permanent magnet segment X-axis suspension winding W. psx The second output terminal Xp1- is connected to the external X-axis suspension control circuit;

[0017] W psy Each set of Y-axis suspension coils has two terminals. The first terminal of the first set of Y-axis suspension coils serves as the permanent magnet segment Y-axis suspension winding W. psy The first output terminal Yp1+, the second terminal of the first set of Y-axis suspension coils is connected to the first terminal of the second set of Y-axis suspension coils, and the second terminal of the second set of Y-axis suspension coils is used as the permanent magnet segment Y-axis suspension winding W psyThe second output terminal Yp1- is connected to the external Y-axis suspension control circuit;

[0018] Among them, W psx 、W psy 、W esx and W esy These four sets of windings are connected to their respective control circuits. For example: the X-axis suspension winding W of the permanent magnet segment psx The control circuit includes: a first MOS switch tube Q1 and a second MOS switch tube Q2 connected in series, a third MOS switch tube Q3 and a fourth MOS switch tube Q4 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 X-axis suspension winding W of the permanent magnet segment is connected. psx The two output terminals are connected to the source of the first MOS switch Q1 and the source of the third MOS transistor Q3 respectively, and the capacitor C1 is connected in parallel to the two ends of the voltage source Us;

[0019] Permanent magnet segment Y-axis suspension winding W psy The control circuit includes: a fifth MOS switch tube Q5 and a sixth MOS switch tube Q6 connected in series, a seventh MOS switch tube Q7 and an eighth MOS switch tube Q8 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 permanent magnet segment Y-axis suspension winding W psy The two output terminals are connected to the source of the fifth MOS switch Q5 and the source of the seventh MOS transistor Q7 respectively, and the capacitor C2 is connected in parallel to the two ends of the voltage source Us;

[0020] X-axis suspension winding W of the electric excitation section esx The control circuit includes: a ninth MOS switch tube Q9 and a tenth MOS switch tube Q10 connected in series, an eleventh MOS switch tube Q11 and a twelfth MOS switch tube Q12 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 X-axis suspension winding W of the electric excitation section is connected. esx The two output terminals are connected to the source of the ninth MOS switch Q9 and the source of the eleventh MOS transistor Q11 respectively, and the capacitor C3 is connected in parallel to the two ends of the voltage source Us;

[0021] Y-axis suspension winding W of the electric excitation section esyThe control circuit includes: a thirteenth MOS switch tube Q13 and a fourteenth MOS switch tube Q14 connected in series, a fifteenth MOS switch tube Q15 and a sixteenth MOS switch tube Q16 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 Y-axis suspension winding W of the electric excitation section is connected. esy The two output terminals are connected to the source of the thirteenth MOS switch tube Q13 and the source of the fifteenth MOS tube Q15 respectively, and the capacitor C4 is connected in parallel to both ends of the voltage source Us.

[0022] Optionally, this solution uses a full-bridge uncontrolled rectifier circuit as an external rectifier circuit to rectify the AC power generated on each phase armature winding, including:

[0023] 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;

[0024] 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;

[0025] LmA, LmB, and LmC represent the three-phase armature windings respectively. The input terminals of LmA, LmB, and LmC are connected to each other.

[0026] The output ends of the three-phase windings LmA, LmB, and LmC are 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 respectively; Figure 5 As shown, the two ends of the capacitor C are connected to the common cathode of the three upper diodes and the common anode of the three lower diodes respectively, and the same is true for the resistor R.

[0027] This solution also designs a suspension control method for the novel parallel hybrid excitation bearingless doubly salient motor, including:

[0028] The actual position of the motor rotor is detected by the X-axis radial displacement sensor installed on the motor end cover;

[0029] Obtain a given value of the suspension force according to the actual position and reference position of the motor rotor;

[0030] Determine the suspension current reference values ​​corresponding to the electric excitation section and the permanent magnet section respectively according to the obtained suspension force given value;

[0031] The current Hall effect sensor is used to measure the actual suspension current corresponding to the electromagnetic section and the permanent magnet section, and the actual suspension current is input into the PI link after the difference is made with the obtained suspension current reference value.

[0032] Specifically, the radial position of the motor rotor is detected by the X-axis radial displacement sensor installed on the motor end cover to obtain the actual position x of the motor rotor electromagnetic excitation section in the X-axis direction. e and the actual position x of the permanent magnet segment in the X-axis direction p , and the difference is respectively input into the X-direction displacement PID control module of the electric excitation section and the permanent magnet section, and the X-direction displacement PID control module outputs the required suspension force F in the X-axis direction of the electric excitation section. esx * , output the required suspension force F in the X-axis direction of the permanent magnet segment psx * ;

[0033] The Y-axis radial displacement sensor installed on the motor end cover detects the radial position of the motor rotor and obtains the actual position y of the motor rotor electromagnetic excitation section in the Y-axis direction. e and the actual position y of the permanent magnet segment in the Y-axis direction p , and then make a difference with the rotor position reference value y*, and the obtained 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 of the electromagnetic excitation section esy * , output the required suspension force F in the Y-axis direction of the permanent magnet segment psy * .

[0034] The required suspension force in the X-axis direction of the electromagnetic excitation section is given as F esx * And the required suspension force F in the Y-axis direction of the electro-excitation section esy * The coordinate transformation of the electric excitation section is input to obtain the X-axis suspension winding current reference value of the electric excitation section and the Y-axis suspension winding current reference value of the electric excitation section.

[0035] The required suspension force in the X-axis direction of the permanent magnet segment is given as F psx * And the required suspension force F in the Y-axis direction of the permanent magnet segment psy * Input into the permanent magnet segment coordinate transformation to obtain the X-axis suspension winding current reference value of the permanent magnet segment of the motor and the Y-axis suspension winding current reference value of the permanent magnet segment.

[0036] F esx *The rotor position angle, armature current and excitation current reference values ​​obtained by sampling are transformed into the excitation section coordinates to obtain the excitation section suspension current reference value i esx * ; F psx * The rotor position angle and armature current obtained by sampling are transformed into the permanent magnet segment coordinates to obtain the permanent magnet segment suspension current reference value i psx * . F esy * The rotor position angle, armature current and excitation current reference values ​​obtained by sampling are transformed into the excitation section coordinates to obtain the excitation section suspension current reference value i esy * ; F psy * The rotor position angle and armature current obtained by sampling are transformed into the permanent magnet segment coordinates to obtain the permanent magnet segment suspension current reference value i psy * .

[0037] The Y-axis suspension winding W of the electric excitation section esy The current Hall sensor measures the actual current i passing through the winding. esy The corresponding suspension winding current reference value i esy * The difference value is input into the corresponding PI link; the X-axis suspension winding W of the electric excitation section is esx The current Hall sensor measures the actual current i passing through the winding. esx The corresponding suspension winding current reference value i esx * The difference value is input into the corresponding PI link; the permanent magnet segment X-axis suspension winding W psx The current Hall sensor measures the actual current i passing through the winding. psx The corresponding suspension winding current reference value i psx * The difference value is input into the corresponding PI link; the Y-axis suspension winding W of the permanent magnet segment is psy The current Hall sensor measures the actual current i passing through the winding. psy The corresponding suspension winding current reference value i psy * The difference value is input into the corresponding PI link.

[0038] The novel parallel hybrid excitation bearingless double-pole motor provided by the embodiment of the present invention can flexibly adjust the phase flux and electromotive force by adjusting the DC excitation current. At the same time, the permanent magnet / electric excitation magnetic field can be used as a bias magnetic field to generate the required suspension force by adjusting the independently embedded suspension winding. Due to the use of two excitation sources, permanent magnet / electric excitation, the power density of the motor is significantly improved, and thanks to the high stability of the permanent magnet bias magnetic field, the adjustment range required for the suspension current during the excitation current adjustment process is greatly reduced. More importantly, when a winding fault such as a short circuit occurs and demagnetization is required, the excitation current is reversed, and the two parts can still stably generate suspension force, greatly improving the reliability of the system's suspension operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. 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 paying any creative work.

[0040] Figure 1 This is a 3D structural diagram of a novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention;

[0041] Figure 2 This is a 3D structural cross-sectional view of the stator portion of a novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention;

[0042] Figure 3(a)-Figure 3(b) This is a schematic diagram of the arrangement structure of the permanent magnet section and the electric excitation section windings of a novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention;

[0043] Figure 4(a)-Figure 4(b) They are schematic diagrams of the connection ends of the permanent magnet winding and the electric excitation winding of the novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention;

[0044] Figure 5 This is an external rectifier circuit of a novel parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention;

[0045] Figure 6(a)-Figure 6(d) Schematic diagrams of control circuits for the X-axis suspension winding of the permanent magnet section, the Y-axis suspension winding of the permanent magnet section, the X-axis suspension winding of the electric excitation section, and the Y-axis suspension winding of the electric excitation section of the novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention;

[0046] Figure 7 This is a block diagram of the suspension control principle of a novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be 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, with examples of the embodiments illustrated in the accompanying drawings. Throughout, identical or similar reference numerals represent identical or similar elements or elements having identical or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and intended only to explain the present invention and are not to be construed as limiting the present invention. Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a," "an," "said," and "the" used herein may also include the plural forms. It should be further understood that the term "comprising" as used in the description of the present invention refers to the presence of the stated features, integers, steps, operations, elements, and / or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when an element is referred to as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or intervening elements may be present. Furthermore, "connected" or "coupled" as used herein may include wireless connections or couplings. The term "and / or" as used herein includes any 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 and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art 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 their meanings in the context of the prior art, and will not be interpreted in an idealized or overly formal sense unless defined as such herein.

[0048] In response to the deficiencies of the existing technology in the background technology, an embodiment of the present invention provides a new parallel hybrid excitation bearingless double-pole motor, which can flexibly adjust the phase flux and electromotive force by adjusting the DC excitation current. At the same time, the permanent magnet / electric excitation magnetic field can be used as a bias magnetic field to generate the required suspension force by adjusting the independently embedded suspension winding. Due to the use of two excitation sources, permanent magnet / electric excitation, the power density of the motor is significantly improved, and thanks to the high stability of the permanent magnet bias magnetic field, the adjustment range required for the suspension current during the excitation current adjustment process is greatly reduced. More importantly, when a winding fault such as a short circuit occurs and demagnetization is required, the excitation current is reversed, and the two parts can still stably generate suspension force, greatly improving the reliability of the system's suspension operation.

[0049] The specific implementation method is as follows Figure 1-7 shown, including:

[0050] Figure 1This is a 3D structural diagram of a novel parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention. Both the electrically excited section and the permanent magnet section adopt a 12 / 8-pole double-salient-pole structure. The electrically excited section rotor core and the permanent magnet section rotor core are salient-pole structures, composed of slot-type core laminations, each with eight rotor poles. The electrically excited section stator core and the permanent magnet section stator core are salient-pole structures, each with 12 stator poles. The gaps between adjacent stator poles form stator slots. There are four permanent magnets, all of the same size and shape. The permanent magnets embedded in the stator core yoke include permanent magnet number one, permanent magnet number two, permanent magnet number three, and permanent magnet number four. Tangentially magnetized permanent magnets are located in the stator core yoke, and the magnetization directions of the permanent magnets corresponding to adjacent stator poles are opposite.

[0051] Figure 2 This is a 3D cross-sectional view of the stator portion of a novel parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention. The excitation section and the permanent magnet section share a set of armature windings. Each armature coil is wound around the stator teeth on the stator core of the excitation section and the permanent magnet section. Each stator tooth is wound around 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 the three armature coils in each group belong to phase A, phase B and phase C respectively, and the armature coils N of the same phase in each group m The armature winding W that constitutes this phase m .

[0052] Figure 3(a) is a schematic diagram of the arrangement structure of the permanent magnet segment winding of the new parallel hybrid excitation bearingless double-salient pole motor according to an embodiment of the present invention. psx It consists of two sets of X-axis suspension coils, which are arranged on the stator poles composed of three stator teeth that are radially opposite to each other on the X-axis. Each set of X-axis suspension coils has two terminals. The first terminal of the first set of X-axis suspension coils serves as the permanent magnet segment X-axis suspension winding W. psx The first output terminal Xp1+, the second terminal of the first set of X-axis suspension coils are connected to the first terminal of the second set of X-axis suspension coils, and the second terminal of the second set of X-axis suspension coils is used as the permanent magnet segment X-axis suspension winding W. psx The second output terminal Xp1- is connected to the external X-axis suspension control circuit. psy It consists of two sets of Y-axis suspension coils, which are arranged on the stator poles composed of three stator teeth that are radially opposite to each other on the Y-axis. Each set of Y-axis suspension coils has two terminals. The first terminal of the first set of Y-axis suspension coils serves as the permanent magnet segment Y-axis suspension winding W. psyThe first output terminal Yp1+, the second terminal of the first set of Y-axis suspension coils is connected to the first terminal of the second set of Y-axis suspension coils, and the second terminal of the second set of Y-axis suspension coils is used as the permanent magnet segment Y-axis suspension winding W psy The second output terminal Yp1- is connected to an external Y-axis suspension control circuit.

[0053] Figure 3(b) is a schematic diagram of the arrangement of the electric excitation windings of the novel parallel hybrid excitation bearingless doubly salient motor according to an embodiment of the present invention. The excitation winding is embedded in the stator pole formed by three stator teeth. Each set of excitation coils is wound in the same manner and each set of excitation coils has a first terminal and a second terminal. The second terminal of the first set of excitation coils is connected in series with the second terminal of the second set of excitation coils in the clockwise direction. The first terminal of the second set of excitation coils is connected in series with the second terminal of the third set of excitation coils in the clockwise direction. The first terminal of the third set of excitation windings is connected in series with the second terminal of the fourth set of excitation coils in the clockwise direction. All the excitation coils are connected in series in sequence to form the excitation winding.

[0054] Figure 4(a) is a schematic diagram of the connection end of the permanent magnet winding of the new parallel hybrid excitation bearingless double salient pole motor according to an embodiment of the present invention. Figure 4(b) is a schematic diagram of the connection end of the electric excitation winding of the new parallel hybrid excitation bearingless double salient pole motor according to an embodiment of the present invention. esx It consists of two sets of X-axis suspension coils, which are arranged on the stator poles composed of three stator teeth that are radially opposite to each other on the X-axis. Each set of X-axis suspension coils has two terminals. The first terminal of the first set of X-axis suspension coils serves as the electric excitation section X-axis suspension winding W. esx The first output terminal Xe1+, the second terminal of the first set of X-axis suspension coils is connected to the first terminal of the second set of X-axis suspension coils, and the second terminal of the second set of X-axis suspension coils serves as the electric excitation section X-axis suspension winding W. esx The second output terminal Xe1- is connected to the external X-axis suspension control circuit. esy It consists of two sets of Y-axis suspension coils, which are arranged on the stator poles composed of three stator teeth that are radially opposite to each other on the Y-axis. Each set of Y-axis suspension coils has two terminals. The first terminal of the first set of Y-axis suspension coils serves as the Y-axis suspension winding W of the electric excitation section. esy The first output terminal Ye1+, the second terminal of the first set of Y-axis suspension coils is connected to the first terminal of the second set of Y-axis suspension coils, and the second terminal of the second set of Y-axis suspension coils serves as the Y-axis suspension winding W of the electric excitation section. esy The second output terminal Ye1- is connected to an external Y-axis suspension control circuit.

[0055] Figure 5This is an external rectifier circuit for a novel parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention. The external rectifier circuit uses a full-bridge uncontrolled rectifier circuit to rectify the alternating current generated by the three-phase armature winding. The circuit includes: a first rectifier diode D1 connected in series with a second rectifier diode D2; a third rectifier diode D3 connected in series with a fourth rectifier diode D4; and a fifth rectifier diode D5 connected in series with a sixth rectifier diode D6. The cathodes of the first rectifier diode D1, the third rectifier diode D3, and the fifth rectifier diode D5 are connected, while the anodes of the second rectifier diode D2, the fourth rectifier diode D4, and the sixth rectifier diode D6 are connected. The input ends of the three-phase armature windings LmA, LmB, and LmC are interconnected. The output ends of the three-phase windings LmA, LmB, and LmC are connected to the anodes of the first rectifier diode D1, the second rectifier diode D2, and the third rectifier diode D3, respectively. A capacitor C and a resistor R are connected in parallel, with their ends connected to the common cathode and common anode of the diodes, respectively.

[0056] FIG6( a ) is a diagram of the X-axis suspension winding W of the permanent magnet section of a novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention. psx Schematic diagram of control circuit. Permanent magnet segment X-axis suspension winding W psx The control circuit includes: a first MOS switch tube Q1 and a second MOS switch tube Q2 connected in series, a third MOS switch tube Q3 and a fourth MOS switch tube Q4 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 X-axis suspension winding W of the permanent magnet segment is connected. psx The equivalent Lpsx and the resistor R1 have two output terminals connected to the source of the first MOS switch Q1 and the source of the third MOS transistor Q3 respectively, and the capacitor C1 is connected in parallel to both ends of the voltage source Us.

[0057] FIG6( b ) is a diagram of the Y-axis suspension winding W of the permanent magnet section of the novel parallel hybrid excitation bearingless doubly salient pole motor according to an embodiment of the present invention. psy Schematic diagram of the control circuit. Permanent magnet segment Y-axis suspension winding W psy The control circuit includes: a fifth MOS switch tube Q5 and a sixth MOS switch tube Q6 connected in series, a seventh MOS switch tube Q7 and an eighth MOS switch tube Q8 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 permanent magnet segment Y-axis suspension winding W psy The Lpsy and the resistor R2 are equivalent, and the two output terminals thereof are respectively connected to the source of the fifth MOS switch tube Q5 and the source of the seventh MOS tube Q7, and the capacitor C2 is connected in parallel to the two ends of the voltage source Us.

[0058] FIG6(c) is a diagram of the X-axis suspension winding W of the electric excitation section of the new parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention. esx Schematic diagram of the control circuit. X-axis suspension winding W of the electric excitation section esx The control circuit includes: a ninth MOS switch tube Q9 and a tenth MOS switch tube Q10 connected in series, an eleventh MOS switch tube Q11 and a twelfth MOS switch tube Q12 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 X-axis suspension winding W of the electric excitation section is connected. esx The equivalent is Lesx and resistor R3, whose two output terminals are connected to the source of the ninth MOS switch Q9 and the source of the eleventh MOS transistor Q11 respectively, and the capacitor C3 is connected in parallel to the two ends of the voltage source Us;

[0059] FIG6(d) is a diagram of the Y-axis suspension winding W of the electric excitation section of the new parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention. esy Schematic diagram of the control circuit. esy The control circuit includes: a thirteenth MOS switch tube Q13 and a fourteenth MOS switch tube Q14 connected in series, a fifteenth MOS switch tube Q15 and a sixteenth MOS switch tube Q16 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 Y-axis suspension winding W of the electric excitation section is connected. esy The equivalent of Lesy and resistor R4, two output terminals of which are respectively connected to the source of the thirteenth MOS switch tube Q13 and the source of the fifteenth MOS tube Q15, and the capacitor C4 is connected in parallel to both ends of the voltage source Us.

[0060] Figure 7 This is a block diagram of the suspension control principle of a novel parallel hybrid excitation bearingless double-salient-pole motor according to an embodiment of the present invention. 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. The radial position of the motor rotor is detected by an X-axis radial displacement sensor mounted on the motor end cap, and the actual position x of the motor rotor's electromagnetic excitation section in the X-axis direction is obtained. e and the actual position x of the permanent magnet segment in the X-axis direction p , and the difference is respectively input into the X-direction displacement PID control module of the electric excitation section and the permanent magnet section, and the X-direction displacement PID control module outputs the required suspension force F in the X-axis direction of the electric excitation section.esx * , output the required suspension force F in the X-axis direction of the permanent magnet segment psx * The radial position of the motor rotor is detected by the Y-axis radial displacement sensor installed on the motor end cover to obtain the actual position y of the motor rotor electromagnetic excitation segment in the Y-axis direction. e and the actual position y of the permanent magnet segment in the Y-axis direction p , and then make a difference with the rotor position reference value y*, and the obtained 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 of the electromagnetic excitation section esy * , output the required suspension force F in the Y-axis direction of the permanent magnet segment psy * . F esx * The rotor position angle, armature current and excitation current reference values ​​obtained by sampling are transformed into the excitation section coordinates to obtain the excitation section suspension current reference value i esx * ; F psx * The rotor position angle and armature current obtained by sampling are transformed into the permanent magnet segment coordinates to obtain the permanent magnet segment suspension current reference value i psx * . F esy * The rotor position angle, armature current and excitation current reference values ​​obtained by sampling are transformed into the excitation section coordinates to obtain the excitation section suspension current reference value i esy * ; F psy * The rotor position angle and armature current obtained by sampling are transformed into the permanent magnet segment coordinates to obtain the permanent magnet segment suspension current reference value i psy * .

[0061] The Y-axis suspension winding W of the electric excitation section esy The current Hall sensor measures the actual current i passing through the winding. esy The corresponding suspension winding current reference value i esy * The difference value is input into the corresponding PI link, and the output PWM signal is input into the H bridge. The switch tube is controlled to be turned on and off according to the duty cycle signal to achieve the tracking of the Y-axis suspension current of the electric excitation section to its reference value; the X-axis suspension winding W of the electric excitation section is input into the H bridge. esx The current Hall sensor measures the actual current i passing through the winding. esx The corresponding suspension winding current reference value i esx* The difference value is input into the corresponding PI link, and the output PWM signal is input into the H bridge. The switch tube is controlled to be turned on and off according to the duty cycle signal to achieve the tracking of the X-axis suspension current of the electromagnetic section to its reference value; the X-axis suspension winding W of the permanent magnet section is connected to the PWM signal. psx The current Hall sensor measures the actual current i passing through the winding. psx The corresponding suspension winding current reference value i psx * The difference value is input into the corresponding PI link, and the output PWM signal is input into the H bridge. The switch tube is controlled to be turned on and off according to the duty cycle signal to achieve the X-axis suspension current of the permanent magnet segment to track its reference value; the Y-axis suspension winding W of the permanent magnet segment is connected to the PWM signal. psy The current Hall sensor measures the actual current i passing through the winding. psy The corresponding suspension winding current reference value i psy * The difference value is input into the corresponding PI link, and the output PWM signal is input into the H-bridge. The switch tube is controlled to be turned on and off according to the duty cycle signal to achieve the tracking of the Y-axis suspension current of the permanent magnet segment to its reference value.

[0062] The novel parallel hybrid excitation bearingless double-pole motor of this embodiment consists of two parallel, coaxial bearingless double-pole motors, one of which is excited by a stator permanent magnet, and the other by an excitation winding. The two parts have independent magnetic flux paths and share a set of armature windings. By adjusting the DC excitation current, the phase flux linkage and electromotive force can be flexibly adjusted. At the same time, the permanent magnet magnetic field and the electric excitation magnetic field can be used as bias magnetic fields to generate the required suspension force by adjusting the independently embedded suspension windings. Due to the simultaneous use of permanent magnet and electric excitation excitation methods, the power density of the motor is significantly improved. Thanks to the high stability of the permanent magnet bias magnetic field, the adjustment range required for the suspension current during the excitation current adjustment process is greatly reduced. In addition, when a winding fault such as a short circuit occurs and demagnetization is required, the excitation current is reversed. By adjusting the current of the two parts in the suspension winding, the suspension force can still be stably generated, greatly improving the reliability of the system's suspension operation.

[0063] 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 embodiment of the present invention, but the protection scope of the present invention is not limited to this. Any changes or replacements that can be easily thought of by any technician familiar with this 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 new parallel hybrid excitation bearingless double-salient pole motor, characterized in that: The main structure of the motor is divided into the electromagnetic section and the permanent magnet section; The electric excitation section includes: an electric excitation section stator core, an electric excitation section suspension winding, an electric excitation section rotor core and an excitation winding; The permanent magnet segment part includes: a permanent magnet segment stator core, a permanent magnet segment suspension winding, a permanent magnet, a permanent magnet segment suspension winding and a permanent magnet segment rotor core; The electromagnetic section and the permanent magnet section share a set of armature windings; The permanent magnets are evenly arranged around the stator core and embedded in the stator core yoke.

2. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 1 is characterized in that: Armature coils are wound on the stator teeth of the stator core of the electromagnetic section and the stator teeth of the stator core of the permanent magnet section respectively; Among them, each stator tooth is wound with an axial armature coil N m The three adjacent stator poles are grouped together. The three armature coils in each group belong to phase A, phase B and phase C respectively. The armature coils of the same phase are connected in series in sequence to form the armature winding of the phase, and the armature windings W of phase A, phase B and phase C are obtained. mA , W mB and W mC ;Each phase armature winding has two terminals and is connected to the external control circuit through these two terminals.

3. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 2 is characterized in that: The excitation coil is embedded in the stator pole formed by three stator teeth. Each set of excitation coils is wound in the same manner and each set of excitation coils has a first terminal and a second terminal. All the excitation coils are connected in series to form an excitation winding. Among them, the second terminal of the first set of excitation coils is connected in series with the second terminal of the second set of excitation coils in the clockwise direction, the first terminal of the second set of excitation coils is connected in series with the second terminal of the third set of excitation coils in the clockwise direction, and the first terminal of the third set of excitation windings is connected in series with the second terminal of the fourth set of excitation coils in the clockwise direction.

4. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 3 is characterized in that: Both the electromagnetic excitation section and the permanent magnet section adopt a 12 / 8 pole double salient pole structure; The salient pole structures of the electromagnetic section rotor core and the permanent magnet section rotor core are both composed of slotted core laminations, each with 8 rotor poles. The stator core of the electromagnetic section and the stator core of the permanent magnet section are also salient pole structures, each with a total of 12 stator poles, and the gaps between adjacent stator poles form stator slots.

5. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 1 is characterized in that: Four permanent magnets of the same size and shape are used; The tangentially magnetized permanent magnets are located on the stator core yoke, and the magnetization directions of the two permanent magnets of adjacent stator poles are opposite.

6. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 1 is characterized in that: The electromagnetic section suspension winding includes: the electromagnetic section X-axis suspension winding W esx And the Y-axis suspension winding W of the electric excitation section esy ; Among them, W esx It consists of two sets of suspension coils arranged on the stator poles composed of three stator teeth and radially opposite to each other on the X axis, and is used to control the X-axis suspension of the electro-magnetic rotor. esy It consists of two sets of suspension coils arranged on the stator poles composed of three stator teeth and radially opposite to each other on the Y axis, and is used to control the Y-axis suspension of the electro-magnetic section rotor; The permanent magnet segment suspension winding includes: permanent magnet segment X-axis suspension winding W psx and the permanent magnet segment Y-axis suspension winding W psy ; Among them, W psx It consists of two sets of suspension coils arranged on the stator poles composed of three stator teeth and radially opposite to each other on the X axis, and is used to control the X-axis suspension of the electro-magnetic rotor. psy It consists of two sets of suspension coils arranged on stator poles composed of three stator teeth and radially opposite to each other on the Y axis, and is used to control the Y-axis suspension of the electromagnetic segment rotor.

7. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 6 is characterized in that: W esx Each set of X-axis suspension coils has two terminals. The first terminal of the first set of X-axis suspension coils is used as the electric excitation section X-axis suspension winding W. esx The first output terminal Xe1+, the second terminal of the first set of X-axis suspension coils is connected to the first terminal of the second set of X-axis suspension coils, and the second terminal of the second set of X-axis suspension coils serves as the electric excitation section X-axis suspension winding W. esx The second output terminal Xe1- is connected to the external X-axis suspension control circuit; W esy Each set of Y-axis suspension coils has two terminals. The first terminal of the first set of Y-axis suspension coils serves as the Y-axis suspension winding W of the electric excitation section. esy The first output terminal Ye1+, the second terminal of the first set of Y-axis suspension coils is connected to the first terminal of the second set of Y-axis suspension coils, and the second terminal of the second set of Y-axis suspension coils serves as the Y-axis suspension winding W of the electric excitation section. esy The second output terminal Ye1- is connected to the external Y-axis suspension control circuit; W psx Each set of X-axis suspension coils has two terminals. The first terminal of the first set of X-axis suspension coils serves as the permanent magnet segment X-axis suspension winding W. psx The first output terminal Xp1+, the second terminal of the first set of X-axis suspension coils are connected to the first terminal of the second set of X-axis suspension coils, and the second terminal of the second set of X-axis suspension coils is used as the permanent magnet segment X-axis suspension winding W. psx The second output terminal Xp1- is connected to the external X-axis suspension control circuit; W psy Each set of Y-axis suspension coils has two terminals. The first terminal of the first set of Y-axis suspension coils serves as the permanent magnet segment Y-axis suspension winding W. psy The first output terminal Yp1+, the second terminal of the first set of Y-axis suspension coils is connected to the first terminal of the second set of Y-axis suspension coils, and the second terminal of the second set of Y-axis suspension coils is used as the permanent magnet segment Y-axis suspension winding W psy The second output terminal Yp1- is connected to the external Y-axis suspension control circuit; W psx 、W psy 、W esx and W esy The four sets of windings are connected to their respective control circuits.

8. The novel parallel hybrid excitation bearingless double-salient-pole motor according to claim 1 is characterized in that: A full-bridge uncontrolled rectifier circuit is used as an external rectifier circuit to rectify the AC power generated on each phase armature winding, including: 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; LmA, LmB, and LmC represent the three-phase armature windings respectively. The input terminals of LmA, LmB, and LmC are connected to each other. The output ends of the three-phase windings LmA, LmB, and LmC are 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, respectively; The capacitor C and the resistor R are connected in parallel, and the two ends of the capacitor C are connected to the common cathode of a group of three diodes and the common anode of another group of three diodes, and the two ends of the resistor R are connected to the common cathode of a group of three diodes and the common anode of another group of three diodes.

9. The novel parallel hybrid excitation bearingless doubly salient pole motor according to any one of claims 1 to 8, characterized in that: Suspension control method, including: The actual position of the motor rotor is detected by the X-axis radial displacement sensor installed on the motor end cover; Obtain a given value of the suspension force according to the actual position and reference position of the motor rotor; Determine the suspension current reference values ​​corresponding to the electric excitation section and the permanent magnet section respectively according to the obtained suspension force given value; The current Hall effect sensor is used to measure the actual suspension current corresponding to the electromagnetic section and the permanent magnet section, and the actual suspension current is input into the PI link after the difference is made with the obtained suspension current reference value.

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