Fault-tolerant control method for modular bearingless doubly salient electro-magnetic motor under fault

Abstract

This invention discloses a fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions, relating to the field of fault-tolerant control for bearingless electrically excited doubly salient pole motors. This scheme uses a three-phase full-bridge converter to control the switching transistors, enabling the three-phase full-bridge converter to operate alternately as a single-phase bridge inverter circuit under normal and fault conditions of the switching transistors, achieving fault tolerance of the switching transistors in the toroidal DC winding control circuit. Under the condition of open circuit and loss of excitation in the toroidal DC winding, fault-tolerant control of rotor levitation of the modular bearingless electrically excited doubly salient pole motor is achieved through the reuse of the armature winding. The method includes a three-phase full-bridge converter control strategy for fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor and an armature winding reuse control strategy for fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor. This further improves the fault tolerance capability of the modular bearingless electrically excited doubly salient pole motor.

Description

Technical Field

[0001] This invention relates to the field of fault-tolerant control of bearingless electrically excited doubly salient pole motors, and particularly to a fault-tolerant control method for modular bearingless electrically excited doubly salient pole motors under fault conditions. Background Technology

[0002] With the advancement of technology, aircraft are gradually moving towards greater electrification and even full electrification. The power rating of starter generators used for aircraft turbofan engines is also increasing, from the original 100W to the 1MW on the B787. This increase in power rating reflects the development of motor technology. However, technological progress also places higher demands on the fault tolerance of motors, and fault-tolerant control of motors is gradually gaining attention from scholars both domestically and internationally. Traditional bearingless electrically excited doubly salient pole motors have a robust and reliable rotor structure, but the stator side is wound with multiple sets of windings, including armature windings, excitation windings, and levitation windings. These windings are stacked on top of each other and have significant coupling effects. A failure in any winding will have a significant impact on other healthy windings and the internal magnetic field of the motor, causing failure in levitation and motor / generator operation.

[0003] This has led to the development of modular bearingless electrically excited doubly salient pole motors, which offer greater reliability compared to traditional bearingless electrically excited doubly salient pole motors. However, modular bearingless electrically excited doubly salient pole motors still lack effective fault-tolerant control schemes. Therefore, how to achieve fault-tolerant control of modular bearingless electrically excited doubly salient pole motors under fault conditions has become a research topic that needs to be addressed. Summary of the Invention

[0004] The embodiments of the present invention provide a fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions, which can further improve the fault tolerance capability of the modular bearingless electrically excited doubly salient pole motor.

[0005] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0006] A fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions includes: a three-phase full-bridge converter control loop and an armature winding multiplexing control loop; wherein, the controlled object is the toroidal DC winding of the modular bearingless electrically excited doubly salient pole motor, and during normal operation, a current component I of the excitation current is applied to the winding. f With the levitation control current component I sx / sy The sum of the control currents forms the excitation magnetomotive force and the levitation magnetomotive force.

[0007] The control circuit of the three-phase full-bridge converter includes: during normal operation of the bearingless electrically excited doubly salient pole motor, the three-phase full-bridge converter used to control the DC toroidal winding operates as a single-phase bridge inverter circuit, wherein the three-phase full-bridge converter outputs control current to the DC toroidal winding; specifically, during normal operation of the bearingless electrically excited doubly salient pole motor, the three-phase full-bridge converter used to control the DC toroidal winding operates as a single-phase bridge inverter circuit, outputting control current to the DC toroidal winding, the amplitude of which is the excitation current component I. f and levitation control current component I sx / sy The sum of (I) sx I sy (These are the x-axis and y-axis floating control current components, respectively). When a switching tube failure occurs in the three-phase full-bridge converter used to control the DC toroidal winding, the three-phase full-bridge converter of this invention replaces another set of switching tubes and operates as a single-phase bridge inverter circuit.

[0008] The armature winding multiplexing control loop includes: when a DC toroidal winding open-circuit fault causes the bearingless electrically excited doubly salient pole motor to lose excitation, the armature winding simultaneously assumes the excitation and levitation functions. Specifically, when a DC toroidal winding open-circuit fault causes the modular bearingless electrically excited doubly salient pole motor to lose excitation, the armature winding simultaneously assumes the excitation and levitation functions by introducing an excitation current component I into the armature winding. f and levitation control current component I sx / sy The sum of the control currents enables demagnetization-tolerant control of modular bearingless electrically excited doubly salient pole motors.

[0009] In this embodiment, in the control loop of the three-phase full-bridge converter, the amplitude of the control current output to the DC toroidal winding is the excitation current component I. f and levitation control current component I sx / sy The sum of, where I sx I sy These represent the floating control current components along the x-axis and y-axis, respectively. When a switching transistor failure occurs in the three-phase full-bridge converter, the three-phase full-bridge converter is replaced with another set of switching transistors and operated as a single-phase bridge inverter circuit.

[0010] The armature winding multiplexing control circuit includes: introducing an excitation current component I into the armature winding. f and levitation control current component I sx / sy The sum of the control currents enables the demagnetization-tolerant control of a modular bearingless electrically excited doubly salient pole motor. For example... Figure 2As shown, the three-phase full-bridge converter includes six switching transistors: T1, T2, T3, T4, T5, and T6. T1, T3, and T5 are located on the upper bridge arm, and T2, T4, and T6 are located on the lower bridge arm. During normal operation, T1, T4, and T5 are in the ON state, while T2, T3, and T6 are in the OFF state, thereby outputting the control current for the toroidal DC winding of the modular bearingless electrically excited doubly salient pole motor. When any of the switching transistors T1, T4, and T5 fails, the three-phase full-bridge converter switches to T2, T3, and T6 operation, thus replacing T1, T4, and T5 and functioning as the control circuit for the toroidal DC winding.

[0011] In this embodiment, a three-phase four-bridge converter is used as the fault-tolerant drive circuit for the armature winding of the modular bearingless electrically excited doubly salient pole motor. When the modular bearingless electrically excited doubly salient pole motor is running normally, the three-phase four-bridge converter outputs three-phase current. When the DC ring winding of the modular bearingless electrically excited doubly salient pole motor experiences an open-circuit fault, it will lead to a demagnetization fault in the modular bearingless electrically excited doubly salient pole motor. The armature winding of the modular bearingless electrically excited doubly salient pole motor outputs an armature current with a ring DC winding control current component through the three-phase four-bridge converter.

[0012] The modular bearingless electrically excited doubly salient pole motor uses two sets of three-phase full-bridge converters to drive four DC ring windings. The three-phase full-bridge converters controlling the DC ring windings of the upper and lower modules have six switching transistors: S11, S14, S13, S16, S15, and S12. The three-phase full-bridge converters controlling the DC ring windings of the left and right modules have six switching transistors: S21, S24, S23, S26, S25, and S22.

[0013] The fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions provided in this invention employs a three-phase full-bridge converter to control the switching transistors. This allows the three-phase full-bridge converter to operate alternately as a single-phase bridge inverter circuit under normal switching transistor operation and fault conditions, achieving fault tolerance for the switching transistors in the toroidal DC winding control circuit. Under conditions of DC winding disconnection and demagnetization, the armature winding is reused to achieve rotor levitation fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor. This method includes a three-phase full-bridge converter control strategy for fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor and an armature winding reuse control strategy for fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor. This fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions of demagnetization and toroidal DC winding switching transistor failure, thereby further improving the operational reliability of the modular bearingless electrically excited doubly salient pole motor. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a block diagram of a modular bearingless electrically excited doubly salient pole motor fault-tolerant control provided in an embodiment of the present invention;

[0016] Figure 2 This is a schematic diagram of a modular bearingless electrically excited doubly salient pole motor structure provided in an embodiment of the present invention;

[0017] Figure 3 A schematic diagram of a three-phase full-bridge converter topology for fault-tolerant control of the toroidal DC winding control circuit of a modular bearingless electrically excited doubly salient pole motor, provided in an embodiment of the present invention.

[0018] Figure 4 A schematic diagram of the winding connection of a three-phase full-bridge converter for fault-tolerant control of the DC ring winding control circuit of a modular bearingless electrically excited doubly salient pole motor, provided in an embodiment of the present invention.

[0019] Figure 5 A schematic diagram of the working principle of a three-phase full-bridge converter for fault-tolerant control of the DC ring winding of a modular bearingless electrically excited doubly salient pole motor, provided in an embodiment of the present invention.

[0020] Figure 6 A topology diagram of a three-phase four-bridge-arm converter for demagnetization fault of a modular bearingless electrically excited doubly salient pole motor provided in an embodiment of the present invention (taking module 1 as an example);

[0021] Figure 7 A schematic diagram of the modular bearingless electrically excited doubly salient pole motor experimental platform provided in an embodiment of the present invention. Detailed Implementation

[0022] 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 with reference to the accompanying drawings and specific embodiments. Embodiments of the present invention will be described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in the specification of the present invention means the presence of the stated 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 groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or couplings. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0023] This invention provides a fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions, such as... Figure 1 The block diagram shown is for a modular bearingless electrically excited doubly salient pole motor with fault-tolerant control. Figure 1 The left side of the middle section is a high-voltage DC busbar, which can be connected to a starting power supply and a DC load. When the modular bearingless electrically excited doubly salient pole motor is running as a motor, it outputs three-phase current to the armature winding by controlling the switching transistors of the three-phase four-arm converter. When the modular bearingless electrically excited doubly salient pole motor is running as a generator, it generates electricity through the three-phase four-arm converter.

[0024] The modular bearingless electrically excited doubly salient pole motor topology in this embodiment includes: a rotor core, a stator core, an armature winding, and a toroidal DC winding; both the rotor core and the stator core are salient pole structures; the stator core is evenly divided into four stator modules: M1, M2, M3, and M4, each stator module having the same shape; the armature winding is wound around the stator poles of the stator core, and the toroidal DC winding is wound around the middle yoke of each stator module. Figure 2 Taking the 24 / 16-pole modular bearingless electrically excited doubly salient pole motor as an example, both the stator and rotor are salient pole structures. Each stator pole is wound with an armature winding (the armature windings in module M1 are labeled CM1-①, AM1-①, BM1-①, CM1-②, AM1-②, BM1-② in clockwise direction; the armature windings in module M2 are labeled CM2-①, AM2-①, BM2-①, CM2-②, AM2-②, BM2-② in clockwise direction; the armature windings in module M3 are labeled CM1-①, AM2-①, BM2-①, CM2-②, AM2-②, BM2-② in clockwise direction). The armature windings within module M4 are labeled CM3-①, AM3-①, BM3-①, CM3-②, AM3-②, and BM3-②, respectively, in clockwise order. To balance the back electromotive force, spatially opposite armature windings of the same phase are connected in series, forming four sets of three-phase armature windings (e.g., AM1-① and AM3-① are connected in series to form the AM1M3-① winding, AM1-② and AM3-② are connected in series to form the AM1M3-② winding). M2-② With B M4-② Series connection constitutes B M2M4-② Each module has an independent external power converter to achieve four-channel motoring and generating operation, or parallel operation (the modular three-phase armature windings in the diagram are connected in series). Each module has an independent toroidal DC winding wound on its stator yoke. Through the three-phase full-bridge converter on the right side of the diagram, the toroidal DC winding outputs an amplitude of excitation current component I to the toroidal DC winding. f With the levitation control current component I sx / sy The control current of the sum, where I sx I sy These are the x-axis and y-axis levitation control current components, respectively.

[0025] like Figure 3 The present invention illustrates a three-phase full-bridge converter for fault-tolerant control of a modular bearingless electrically excited doubly salient pole motor. The circuit topology consists of a DC power supply E, six switching transistors (T1, T2, T3, T4, T5, T6), and two windings W1 and W2. W1 and W2 are connected to a toroidal DC winding. Specific connection details are shown in [details omitted]. Figure 4 .

[0026] like Figure 4The diagram shows the winding connection of a three-phase full-bridge converter for fault-tolerant control of a modular bearingless electrically excited doubly salient pole motor according to the present invention.

[0027] The DC ring windings on the relative stator modules share a single three-phase full-bridge converter. The modular bearingless electrically excited doubly salient pole motor uses two sets of three-phase full-bridge converters to drive four DC ring windings. In the figure, the three-phase full-bridge converter controlling the DC ring windings of the upper and lower modules has six switching transistors: S11, S14, S13, S16, S15, and S12. DCM1 and DCM3 are the DC ring windings of the upper and lower modules, respectively. Similarly, the three-phase full-bridge converter controlling the DC ring windings of the left and right modules has six switching transistors: S21, S24, S23, S26, S25, and S22. DCM2 and DCM4 are the DC ring windings of the left and right modules, respectively.

[0028] like Figure 5 The diagram shows the working principle of the three-phase full-bridge converter for fault-tolerant control of the DC toroidal winding of a modular bearingless electrically excited doubly salient pole motor according to the present invention.

[0029] by Figure 2 Taking DCM1 and DCM3 as examples, when the modular bearingless electrically excited doubly salient pole motor is running normally, Figure 4 The three switching transistors S14, S13, and S12 operate in switching mode, outputting control currents for DCM1 and DCM3. The amplitude of the control current is equal to the excitation current component I. f and levitation control current component I sx / sy The sum of these three switches enables the levitation and excitation of the modular bearingless electrically excited doubly salient pole motor. Similarly, during normal operation, the three switches S24, S23, and S22 operate in the switching state, outputting control currents for DCM2 and DCM4. When any of the switches S14, S13, and S12 fails, S11, S16, and S15 switch in the switching state, while S14, S13, and S12 operate in the off state, achieving fault-tolerant control of the DC toroidal winding control circuit. In this case, the direction of the control current on the DC toroidal winding is opposite to that during normal operation. Similarly, when any of the switches S24, S23, and S22 fails, S21, S26, and S25 switch in the switching state, while S24, S23, and S22 operate in the off state.

[0030] like Figure 6The diagram shows the topology of a three-phase four-arm converter for fault tolerance of loss-of-excitation in a modular bearingless electrically excited doubly salient pole motor according to the present invention (taking module 1 as an example). The circuit topology uses a total of 8 switching transistors: four transistors (S13, S33, S35, and S37) in the upper arm, and four transistors (S34, S36, S32, and S38) in the lower arm. TR is a bidirectional trigger diode. A M1M3-① B M1M3-① C M1M3-① These are the three-phase armature windings on module 1 (taking the armature windings connected in series with the module armature windings as an example). During normal operation, the three-phase four-arm converter operates as the control circuit for the armature windings. When a circuit failure occurs in the toroidal DC winding of the modular bearingless electrically excited doubly salient pole motor, causing the motor to enter a demagnetization state, the armature windings simultaneously operate as the excitation levitation windings. At this time, the output of the three-phase four-arm converter carries an excitation current component I. f and levitation control current component I sx / sy The control current is used to keep the rotor stably suspended.

[0031] The main advantage of this embodiment is that it focuses on a modular bearingless electrically excited doubly salient pole motor, which, compared to traditional bearingless electrically excited doubly salient pole motors, offers advantages such as high reliability, flexible winding arrangement, and low inter-winding coupling. This embodiment implements fault-tolerant control for the modular bearingless electrically excited doubly salient pole motor, further improving its operational reliability. Furthermore, the control approach of this embodiment is simple and easy to implement. For example, it can employ methods such as... Figure 7 The schematic diagram of the experimental platform for the modular bearingless electrically excited doubly salient pole motor of the present invention is shown for testing. This embodiment achieves fault tolerance in two ways: First, a three-phase full-bridge converter is used to control the switching transistors, allowing the three-phase full-bridge converter to operate alternately as a single-phase bridge inverter circuit under normal switching transistor operation and fault conditions, thus achieving fault tolerance of the switching transistors in the toroidal DC winding control circuit. Second, under conditions of DC winding disconnection and demagnetization, the armature winding is reused to achieve rotor levitation fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor. This method includes a three-phase full-bridge converter control strategy for fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor and an armature winding reuse control strategy for fault-tolerant control of the modular bearingless electrically excited doubly salient pole motor. The fault-tolerant control method for modular bearingless electrically excited doubly salient pole motors of the present invention enables fault-tolerant operation of the modular bearingless electrically excited doubly salient pole motor under conditions of demagnetization fault and toroidal DC winding switch failure. The method is highly reliable, easy to operate, and convenient to deploy, further improving the operational reliability of the modular bearingless electrically excited doubly salient pole motor and providing a reference for the further development of fault-tolerant control of modular bearingless electrically excited doubly salient pole motors.

[0032] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on its differences from other embodiments. In particular, the device embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. The above descriptions are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A fault-tolerant control method for a modular bearingless electrically excited doubly salient pole motor under fault conditions, characterized in that, include: Three-phase full-bridge converter control loop and armature winding multiplexing control loop; The control circuit of the three-phase full-bridge converter includes: when the bearingless electrically excited doubly salient pole motor is running normally, the three-phase full-bridge converter used to control the DC ring winding is operated as a single-phase bridge inverter circuit, wherein the three-phase full-bridge converter outputs control current to the DC ring winding. The armature winding multiplexing control link includes: when a DC toroidal winding open circuit fault causes the bearingless electrically excited doubly salient pole motor to lose its magnetization, the armature winding simultaneously undertakes the excitation and levitation functions; In the control loop of the three-phase full-bridge converter, the amplitude of the control current output to the DC toroidal winding is the excitation current component I. f and levitation control current component I sx / sy The sum of, where I sx I sy These are the x-axis and y-axis levitation control current components, respectively. When the three-phase full-bridge converter experiences a switching transistor failure, the three-phase full-bridge converter is replaced with another set of switching transistors and operated as a single-phase bridge inverter circuit. The three-phase full-bridge converter includes six switching transistors T1, T2, T3, T4, T5, and T6. T1, T3, and T5 are located on the upper bridge arm, and T2, T4, and T6 are located on the lower bridge arm. During normal operation of the three-phase full-bridge converter, T1, T4, and T5 are in the on state, while T2, T3, and T6 are in the off state, thereby outputting the control current for controlling the toroidal DC winding of the modular bearingless electrically excited doubly salient pole motor. When any of the switching transistors T1, T4, and T5 fails, the three-phase full-bridge converter switches to operation as T2, T3, and T6, thereby replacing T1, T4, and T5 and operating as the control circuit for the toroidal DC winding. The armature winding multiplexing control circuit includes: introducing an excitation current component I into the armature winding. f and levitation control current component I sx / sy The sum of the control currents.

2. The method according to claim 1, characterized in that, A three-phase four-bridge converter is used as the armature winding fault-tolerant drive circuit of a modular bearingless electrically excited doubly salient pole motor; when the modular bearingless electrically excited doubly salient pole motor is running normally, the three-phase four-bridge converter outputs three-phase current; When an open-circuit fault occurs in the DC ring winding of the modular bearingless electrically excited doubly salient pole motor, the armature winding of the modular bearingless electrically excited doubly salient pole motor outputs an armature current with a ring DC winding control current component through the three-phase four-bridge converter.

3. The method according to claim 1 or 2, characterized in that, The modular bearingless electrically excited doubly salient pole motor uses two sets of three-phase full-bridge converters to drive four DC ring windings. The three-phase full-bridge converters controlling the DC ring windings of the upper and lower modules have six switching transistors: S11, S14, S13, S16, S15, and S12. The three-phase full-bridge converters controlling the DC ring windings of the left and right modules have six switching transistors: S21, S24, S23, S26, S25, and S22.

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