High-reliability fault-tolerant motor based on phase change material

Abstract

The invention relates to the technical field of motors, and discloses a phase change material-based high-reliability fault-tolerant motor, which comprises a casing, a stator and a rotor, and is characterized in that the stator comprises a stator iron core and a stator winding, the stator iron core is detachably mounted in the casing, and a plurality of excitation teeth and a plurality of fault-tolerant teeth are arranged on the inner side of the stator iron core; the plurality of excitation teeth and the plurality of fault-tolerant teeth are respectively and uniformly distributed along the periphery of the stator iron core, the excitation teeth and the fault-tolerant teeth are alternately arranged, stator windings are wound on the excitation teeth, the fault-tolerant teeth are provided with separation grooves which are arranged along the radial direction of the stator iron core, and the separation grooves are filled with phase-change materials. When the input current of the stator winding is increased or a short circuit fault occurs, the heat generated by the stator winding is increased, and the heat is absorbed by the phase change material in the separation groove after being transmitted to the stator iron core, so that the normal work of the motor is ensured, and the improvement of the power of the motor and the improvement of the reliability of the motor are facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of motors, and in particular to a high-reliability fault-tolerant motor based on phase change materials. Background Art

[0002] As a key core component of aircraft, actuators have a huge impact on the flight stability, controllability and safety of aircraft. Actuators are mainly divided into three types: hydraulic actuators, electrostatic fluid actuators and electromechanical actuators. Among them, electromechanical actuators have attracted the attention of researchers at home and abroad due to their advantages such as not requiring complex hydraulic pipelines, no oil leakage problems, and higher control accuracy. Electromechanical actuators convert rotational motion into linear motion by driving the ball screw through the rotation of the motor. The motor in the electromechanical actuator is the core, which directly determines the output performance of the electromechanical actuator.

[0003] For aircraft, reliability and safety are the first indicators. Power density is the second indicator. Therefore, how to achieve high power density of the motor while ensuring the reliability and safety of the motor of the electromechanical actuator has great application value and practical significance. The traditional solution to improve the reliability of electromechanical actuators is to use two motors, one motor works normally, and the other motor is used for cold backup or hot backup; in addition, some people have proposed a multi-phase motor solution. When one phase winding fails, the other phase windings will adjust the current amplitude and phase to achieve fault tolerance.

[0004] The reliability of equipment can be improved through cold backup or hot backup of motors. Both methods use two motors to drive the same mechanical structure. Cold backup means that when one motor is working, the other motor is not working. When one motor fails, the other motor starts working. Hot backup means that during normal operation, the two motors work at the same time. When one motor fails, the other motor works at twice the power. This method of improving reliability is based on sacrificing power density. When a motor fails, the mass of this motor does not contribute to the system power.

[0005] The use of multi-phase windings allows multi-phase windings to share a stator and rotor. When a phase of the motor fails, the current of the phase winding is directly cut off, and the output characteristics of normal operation are achieved by adjusting the current amplitude and phase of other phase windings. This method of improving reliability has the characteristics of high power density. However, when a phase winding short-circuit fault occurs, since the rotor is still rotating at high speed, the alternating magnetic field will cut the phase winding, thereby generating an alternating electromotive force. Since the resistance of the winding is very small, a large current and heat will be generated. If this part of the heat cannot be dissipated, it will have a bad effect on other phase windings and insulation materials inside the motor. The heat dissipation methods of the motor are mainly air cooling, water cooling and oil cooling. Air cooling is not suitable for aircraft, because as the aircraft's flight altitude increases, the air will become thinner and thinner, so the efficiency of air cooling will become lower and lower. Water cooling and oil cooling require additional heat dissipation equipment, which will undoubtedly increase the take-off mass of the aircraft and is uneconomical. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a high-reliability fault-tolerant motor based on phase change material, which absorbs heat generated by stator windings through the phase change material.

[0007] In order to solve the above technical problems, the present invention provides a high-reliability fault-tolerant motor based on phase change material, including a casing, a stator and a rotor, the stator including a stator core and a stator winding, the stator core being detachably installed in the casing, a plurality of excitation teeth and a plurality of fault-tolerant teeth being provided on the inner side of the stator core, the plurality of excitation teeth and the plurality of fault-tolerant teeth being respectively evenly distributed along the outer circumference of the stator core, the excitation teeth and the fault-tolerant teeth being alternately arranged, the stator winding being wound around the excitation teeth, the fault-tolerant teeth being provided with partition grooves arranged along the radial direction of the stator core, and the partition grooves being filled with phase change material.

[0008] As a preferred solution of the present invention, the separation groove runs through the inner side and the outer side of the fault-tolerant tooth, and a plurality of the separation grooves divide the stator core into a plurality of separable and equal stator modules.

[0009] As a preferred solution of the present invention, the grooves around the separation groove are filled with sealant to prevent the phase change material from leaking out.

[0010] As a preferred solution of the present invention, the phase change material is coated with a sealing film to form a phase change block matched with the separation groove, and the phase change block is fixedly connected to the stator module.

[0011] As a preferred solution of the present invention, a positioning groove is provided on the inner side of the casing, and the positioning groove passes through both ends of the casing along the axial direction of the casing. A positioning protrusion cooperating with the positioning groove is provided on the outer side of the stator module.

[0012] As a preferred embodiment of the present invention, the yoke of the stator module is provided with two connecting grooves, one of which is connected to the dividing groove located on one side of the stator module, and the other connecting groove is connected to the dividing groove located on the other side of the stator module, and the connecting grooves are filled with the phase change material.

[0013] As a preferred solution of the present invention, the two connecting grooves are symmetrically arranged with respect to the axis of the exciting tooth and are not connected to each other.

[0014] As a preferred embodiment of the present invention, the stator winding includes an A-phase winding, a B-phase winding, a C-phase winding, a D-phase winding and an E-phase winding.

[0015] Compared with the prior art, the high-reliability fault-tolerant motor based on phase change material in the embodiment of the present invention has the following beneficial effects: when the input current of the stator winding increases or a short circuit fault occurs, the heat generated by the stator winding increases, and the heat is transferred to the stator core and absorbed by the phase change material in the partition slot. Since the working time of the electromechanical actuator is short, the phase change heat dissipation material can quickly absorb the heat during this time, thereby preventing the internal temperature of the motor from being too high and causing demagnetization of the magnetic steel, thereby ensuring the normal operation of the motor, helping to improve the power of the motor and improving the reliability of the motor; thereafter, during non-working hours, the heat energy stored in the phase change material diffuses to the external environment and slowly dissipates the heat, and the phase change material returns to its original state, which will not affect the operation of the electromechanical actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the present invention;

[0017] Figure 2 It is a schematic structural diagram of the connection between the connecting groove and the separating groove of the present invention;

[0018] In the figure, 1. casing; 11. positioning groove; 2. stator; 21. stator core; 211. excitation tooth; 212. fault-tolerant tooth; 213. separation groove; 214. phase change material; 215. positioning protrusion; 216. connecting groove; 222. stator winding; 221. A-phase winding; 222. B-phase winding; 223. C-phase winding; 224. D-phase winding; 225. E-phase winding; 23. stator module; 3. rotor. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0020] In the description of the present invention, it should be understood that the present invention adopts the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0021] like Figure 1 As shown, a high-reliability fault-tolerant motor based on phase change material according to a preferred embodiment of the present invention comprises a housing 1, a stator 2 and a rotor 3, wherein the stator 2 comprises a stator core 21 and a stator winding 222, the stator core 21 is detachably mounted in the housing 1, a plurality of excitation teeth 211 and a plurality of fault-tolerant teeth 212 are arranged on the inner side of the stator core 21, the number of the excitation teeth 211 and the number of the fault-tolerant teeth 212 are the same, the plurality of excitation teeth 211 and the plurality of fault-tolerant teeth 212 are respectively uniformly distributed along the outer circumference of the stator core 21, the excitation teeth 211 and the fault-tolerant teeth 212 are alternately arranged, the stator winding 222 is wound on the excitation teeth 211, and the stator winding 222 comprises a multi-phase winding When only one phase of the stator winding 222 is energized, based on the principle of minimum magnetic resistance, the magnetic circuit will pass through the fault-tolerant tooth 212, and there are few magnetic circuits connecting other phases, thereby realizing magnetic isolation between the two phases. Therefore, when one phase winding fails, the faulty phase winding will not affect other phase windings. The fault-tolerant tooth 212 is provided with a separation groove 213 arranged along the radial direction of the stator core 21, and the separation groove 213 is filled with a phase change material 214. The phase change material 214 can change its physical state within a certain temperature range, for example, from solid to liquid, and absorb heat at the same time, while its own temperature remains basically unchanged during the phase change process.

[0022] The working principle of this embodiment is as follows: since the stator winding 222 is wound on the excitation tooth 211, and the separation slot 213 is arranged at the fault-tolerant tooth 212, the arrangement of the separation slot 213 and the phase change material 214 will not affect the operation of the stator winding 222; when one of the phase windings in the stator winding 222 fails, the fault-tolerant tooth 212 can play a role in magnetic field isolation, thereby preventing the faulty phase winding from affecting other phase windings; when the input current of the stator winding 222 increases or a short circuit fault occurs, the heat generated by the stator winding 222 increases, and the heat is transferred to the stator winding 222. The heat of the iron core 21 is then absorbed by the phase change material 214 in the separation groove 213. Since the working time of the electromechanical actuator is short (roughly tens of seconds), the phase change heat dissipation material can quickly absorb the heat during this time, thus preventing the internal temperature of the motor from being too high and causing the magnetic steel to demagnetize, thereby ensuring the normal operation of the motor, helping to improve the power of the motor and improving the reliability of the motor; thereafter, during non-working hours, the heat energy stored in the phase change material 214 diffuses to the external environment and slowly dissipates the heat, and the phase change material 214 returns to its original state, which will not affect the operation of the electromechanical actuator.

[0023] Exemplarily, the dividing groove 213 passes through the inner and outer sides of the fault-tolerant teeth 212, which helps to improve the heat absorption efficiency of the phase change material 214. The dividing groove 213 passes through the axial ends of the fault-tolerant teeth 212. The multiple dividing grooves 213 split the stator core 21 into multiple separable and equal stator modules 23, that is, each stator module 23 can be disassembled and assembled separately, which is convenient for the assembly of the motor. When one of the stator windings 222 fails, it is only necessary to remove the stator module 23 corresponding to the stator winding 222 to replace the faulty stator winding 222, without removing the entire stator 2, which is convenient for maintenance.

[0024] Exemplarily, the grooves around the dividing groove 213 are filled with sealant to prevent the phase change material 214 from leaking out, so as to prevent the phase change material 214 from flowing and leaking during the endothermic phase change. In another embodiment of the invention, the phase change material 214 is coated with a sealing film to form a phase change block that cooperates with the dividing groove 213. The setting of the sealing film prevents the phase change material 214 from leaking out. The phase change block is fixedly connected to the stator module 23. The stator module 23 and the phase change block can be pre-fabricated and fixed together for easy assembly.

[0025] Exemplarily, a positioning groove 11 is provided on the inner side of the casing 1, and the positioning groove 11 passes through both ends of the casing 1 along the axial direction of the casing 1. A positioning protrusion 215 that cooperates with the positioning groove 11 is provided on the outer side of the stator module 23 to facilitate the positioning and installation of the stator module 23 in the casing 1. In this embodiment, the positioning groove 11 is a dovetail groove, which can prevent the stator module 23 from being offset radially and circumferentially along the casing 1.

[0026] Exemplarily, the stator winding 222 includes an A-phase winding 221, a B-phase winding 222, a C-phase winding 223, a D-phase winding 224 and an E-phase winding 225, that is, this embodiment is a five-phase motor, each phase is controlled by its own drive signal, can improve the accuracy of torque output and motion control, and reduce vibration and noise, and is suitable for use in aircraft. When one of the phase windings fails, taking the failure of the A-phase winding 221 as an example, the current of the A-phase winding 221 is cut off, and the current phase and current amplitude of the B-phase winding 222, the C-phase winding 223, the D-phase winding 224 and the E-phase winding 225 are adjusted to maintain normal operation of the motor. At this time, the phase change material 214 in the dividing slots 213 on both sides of the A-phase winding 221 can absorb the heat generated by the A-phase winding 221 to prevent demagnetization of the magnetic steel due to excessive temperature, thereby ensuring the normal operation of the motor and the high reliability of the motor.

[0027] For example, Figure 2 As shown, the yoke of the stator module 23 is provided with two connecting grooves 216. Generally, the connecting groove 216 is in an arc shape arranged around the axis of the stator core 21. There is a gap between the outer side of the connecting groove 216 and the outer side of the yoke of the stator core 21, and there is a gap between the inner side of the connecting groove 216 and the inner side of the yoke of the stator core 21. One of the connecting grooves 216 is connected to the dividing groove 213 located on one side of the stator module 23, and the other connecting groove 216 is connected to the dividing groove 213 located on the other side of the stator module 23. The connecting groove 216 is filled with phase change material 214. The phase change material 214 in the connecting groove 216 can further absorb heat from the stator module 23. At the same time, since the connecting groove 216 is connected to the dividing groove 213, the phase change material 214 in the two can transfer heat to each other, thereby helping to keep the temperature of the stator module 23 uniform.

[0028] Exemplarily, the two connecting grooves 216 are symmetrically arranged about the axis of the excitation tooth 221 and are not connected to each other, that is, the two connecting grooves 216 are separated by the yoke part of the stator module 23 corresponding to the excitation tooth 221, so that the connecting groove 216 will not split the stator module 23 into two parts, inner and outer parts, thereby ensuring the rigidity of the overall structure of the stator module 23 and preventing the stator core 21 from shifting when the phase change material 214 in the connecting groove 216 changes phase, thereby ensuring the normal operation of the stator module 23.

[0029] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A high reliability fault-tolerant motor based on phase change material, comprising a housing, a stator and a rotor, characterized in that: The stator includes a stator core and a stator winding. The stator core is detachably installed in the casing. A plurality of excitation teeth and a plurality of fault-tolerant teeth are provided on the inner side of the stator core. The plurality of excitation teeth and the plurality of fault-tolerant teeth are evenly distributed along the outer circumference of the stator core, respectively. The excitation teeth and the fault-tolerant teeth are alternately arranged. The stator winding is wound around the excitation teeth. The fault-tolerant teeth are provided with dividing grooves arranged along the radial direction of the stator core. The dividing grooves are filled with phase change material.

2. The high reliability fault-tolerant motor based on phase change material according to claim 1, characterized in that: The separation grooves penetrate the inner side and the outer side of the fault-tolerant teeth, and a plurality of the separation grooves divide the stator core into a plurality of separable and equal stator modules.

3. The high reliability fault-tolerant motor based on phase change material according to claim 2, characterized in that: The grooves around the separation groove are filled with sealant to prevent the phase change material from leaking out.

4. The high reliability fault-tolerant motor based on phase change material according to claim 2, characterized in that: The phase change material is coated with a sealing film to form a phase change block matched with the separation groove, and the phase change block is fixedly connected to the stator module.

5. The high reliability fault-tolerant motor based on phase change material according to claim 2, characterized in that: A positioning groove is provided on the inner side of the housing, and the positioning groove passes through two ends of the housing along the axial direction of the housing. A positioning protrusion matched with the positioning groove is provided on the outer side of the stator module.

6. The high reliability fault-tolerant motor based on phase change material according to claim 2, characterized in that: The yoke of the stator module is provided with two connecting grooves, one of which is connected to the dividing groove located on one side of the stator module, and the other connecting groove is connected to the dividing groove located on the other side of the stator module, and the connecting grooves are filled with the phase change material.

7. The high reliability fault-tolerant motor based on phase change material according to claim 6, characterized in that: The two communicating grooves are symmetrically arranged with respect to the axis of the exciting tooth and are not connected to each other.

8. The high reliability fault-tolerant motor based on phase change material according to claim 1, characterized in that: The stator winding includes an A-phase winding, a B-phase winding, a C-phase winding, a D-phase winding and an E-phase winding.

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