A dual resolver transition shaft connection structure

Abstract

A dual resolver transition shaft connection structure includes a pitch motor main shaft, a first resolver rotor, a second resolver rotor, and a transition shaft. The transition shaft includes a locking section and a coaxial screw section, a first radial positioning section, and a second radial positioning section. An axial screw hole is further provided at one end of the transition shaft on the side of the second radial positioning section, and the screw hole is coaxially arranged with the pitch motor main shaft; the screw hole and the screw section have the same thread rotation mode. At least two locking platforms are provided axially on the locking section. The connection structure further includes a fixing screw that is arranged in cooperation with the screw hole, and a resolver rotor pressing plate that is threadedly sleeved on the outer periphery of the fixing screw. In the assembled state, the screw section is threadedly connected to one end of the pitch motor main shaft, and the screw hole is threadedly connected to the fixing screw and the resolver rotor pressing plate respectively. Using the present invention can effectively improve the control accuracy and reliability of the dual resolver structure.

Description

Technical Field

[0001] The present invention relates to the field of motor processing, and particularly to a dual resolver transition shaft connection structure. Background Art

[0002] In a wind power system, pitch control is achieved by adjusting the pitch angle of the blade, changing the angle of attack of the air flow on the blade, and then controlling the aerodynamic torque and power captured by the wind turbine. Stable pitch control has become one of the hotspots and difficulties in the research of control technologies for current large-scale wind turbines.

[0003] With the development of wind power technology, the most widely used pitch motor in wind power generation is the permanent magnet pitch motor, and people have higher and higher requirements for its control accuracy and reliability. The installation accuracy of the resolver of the permanent magnet pitch motor directly affects the control accuracy and reliability of the permanent magnet pitch motor. The structure and fit of the resolver rotor, as part of the resolver installation, directly affect the installation accuracy of the resolver, especially the design of the installation structure of the second resolver of the dual resolver.

[0004] In the prior art, for the mainstream design of permanent magnet pitch motors, the installation method of a single resolver is mostly adopted, and the dual resolver method is less used. The current dual resolver structure generally uses a long tail shaft to uniformly position the motor rotor and two identical resolver rotors. This structure has certain drawbacks. On the one hand, the long tail shaft structure is prone to deformation during processing and has a large vibration amplitude, affecting the control accuracy and reliability of the motor. On the other hand, after the two resolvers are uniformly positioned, the first resolver rotor cannot be fixed independently, so the resolver stator angle must be adjusted. However, if it is difficult to determine the lead direction of the resolver stator, it will lead to difficulties in fixing the leads; moreover, since the resolver stator is fixed using a multi-bolt structure, it is easy to have unbalanced forces during fixed crimping, and the position of the resolver stator is prone to displacement, thereby increasing the error of the resolver angle and also affecting the control accuracy and reliability of the motor.

[0005] In view of this, how to design a dual resolver transition shaft connection structure that can effectively solve the problems of low control accuracy and poor reliability of the dual resolver shaft structure is the research topic of the present invention. Summary of the Invention

[0006] The present invention provides a dual resolver transition shaft connection structure, aiming at the dual resolver structure of the pitch motor to achieve high control accuracy and high reliability.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows: A dual resolver transition shaft connection structure includes a pitch motor main shaft, a first resolver rotor and a second resolver rotor coaxially arranged with the pitch motor main shaft. The innovation lies in that: it further includes a transition shaft, which is positioned and connected to one end of the pitch motor main shaft to fix the first resolver rotor and the second resolver rotor.

[0008] The transition shaft includes a screw segment, a first radial positioning segment, a locking segment and a second radial positioning segment that are sequentially positioned and connected along the axial direction. Among them, the screw segment, the first radial positioning segment and the second radial positioning segment are of a rotating body structure and are coaxially arranged with the pitch motor main shaft in the assembled state; the diameter of the screw segment is smaller than the diameter of the first radial positioning segment, and the diameters of the first radial positioning segment and the second radial positioning segment are both smaller than the diameter of the locking segment.

[0009] One end of the transition shaft on the side of the second radial positioning segment is also provided with an axial screw hole that is coaxially arranged with the pitch motor main shaft; the screw hole and the screw segment of the transition shaft have the same thread rotation mode; the transition shaft connection structure further includes a fixing screw that is matched with the screw hole, and a resolver rotor pressing plate that is threadedly sleeved on the outer periphery of the fixing screw.

[0010] At least two locking platforms are provided along the axial direction on the locking segment.

[0011] In the assembled state, the screw segment is threadedly connected to one end of the pitch motor main shaft; one axial end of the first resolver rotor is sleeved on the outer periphery of the first radial positioning segment, and the other end is sleeved on the end of the connecting screw segment of the pitch motor main shaft to make the first resolver rotor coaxially arranged with the pitch motor main shaft; the end face of the locking segment on the side of the first radial positioning segment is in press-fit with the corresponding end face of the first resolver rotor; one axial end of the second resolver rotor is sleeved on the second radial positioning segment, and the other end is sleeved on the outer periphery of one end of the resolver rotor pressing plate; the screw hole is threadedly connected to the fixing screw and the resolver rotor pressing plate respectively; the end face of the locking segment on the side of the second radial positioning segment is in press-fit with the corresponding end face of the second resolver rotor.

[0012] The explanations of the relevant content in the above technical solution are as follows:

[0013] 1. In this solution, the "same thread rotation mode" of the screw thread segment and the screw hole of the transition shaft means that both of their thread structures are clockwise helices or both are counterclockwise helices. The transition shaft connection structure combined with this design can independently adjust the electrical angle of the two resolvers respectively and fix them firmly. Thereby, it can avoid the electrical angle deviation caused by the loosening of the position of the first resolver rotor when the second resolver is adjusted after the electrical angle of the first resolver is adjusted.

[0014] 2. In this solution, in the assembled state, the screw rod section is divided into a threaded mating section and an external section. Among them, the threaded mating section refers to the part of the screw rod section that is screwed into the end of the pitch motor main shaft, and the external section refers to the part of the screw rod section that is not screwed into the end of the pitch motor main shaft. This design reduces the stress concentration caused by the concentricity difference between the locking section and the first radial positioning section through elastic fitting, and weakens the negative impact of the concentricity difference on the entire shaft structure. Preferably, the length of the external section is 1 to 2 times the diameter of the screw rod section. As a further preference, the length of the threaded mating section is 1.5 to 2.5 times the diameter of the screw rod section.

[0015] 3. In this solution, preferably, on one side of the locking section close to the first radial positioning section is a baffle part, and on the other side is a platform part. The locking platforms are all arranged on the platform part; the baffle part and the platform part are fixedly connected; the distance from the outer circumference to the axis of the platform part is less than the diameter of the baffle part. The design of this baffle part is used to prevent the wrench from knocking and damaging the resolver rotor winding during assembly.

[0016] 4. In this solution, as a further preference, there are four locking platforms on the platform part. In the cross-section, these four locking platforms are symmetrically arranged with the axis as the reference and are located on a square centered on the axis.

[0017] The design principle and beneficial effects of the present invention are as follows:

[0018] First of all, the present invention adopts a double resolver transition shaft connection structure that is relatively independent of the pitch motor main shaft, combined with an external thread structure of a screw rod structure at one end and an internal thread structure of a screw hole structure at the other end, which can independently adjust the electrical angle of the two resolvers respectively and fix them firmly. Therefore, it can avoid the electrical angle deviation caused by the loosening of the first resolver rotor position when the second resolver is adjusted after the first resolver adjusts the electrical angle. Therefore, the present invention can effectively improve the control accuracy and reliability of the double resolver structure.

[0019] Secondly, in this double resolver transition shaft connection structure, the settings of the first radial positioning section, the second radial positioning section, and the locking section of the transition shaft can effectively position and lock the two resolvers. Among them, the baffle part provided in the locking section is used to prevent the wrench from knocking and damaging the resolver rotor winding during assembly, which can reduce the risk of accidental electrical failures and improve reliability.

[0020] In addition, in the assembled state, there is still an external part left in the screw rod section and it is not fully screwed into the pitch motor main shaft. This design reduces the stress concentration caused by the concentricity difference between the locking section and the first radial positioning section through elastic fitting, and weakens the negative impact of the concentricity difference on the entire shaft structure, thereby further improving the control accuracy of the double resolver structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Attached Figure 1 FIG. is a partial structural cross-sectional view of the double resolver transition shaft connection structure of the present invention assembled in a pitch motor;

[0022] Attached Figure 2 FIG. is a three-dimensional structural schematic diagram of the transition shaft of the double resolver transition shaft connection structure of the present invention;

[0023] Attached Figure 3 FIG. is an axial plane schematic diagram of the transition shaft of the double resolver transition shaft connection structure of the present invention;

[0024] Attached Figure 4 Is Figure 3 Axial sectional view of;

[0025] Attached Figure 5 FIG. is a radial schematic diagram of the transition shaft of the double resolver transition shaft connection structure of the present invention.

[0026] In the above drawings: 1. Transition shaft; 2. Screw section; 201. Threaded mating section; 202. External section; 3. First radial positioning section; 4. Locking section; 401. Baffle part; 402. Platform part; 4021. Locking platform; 5. Second radial positioning section; 6. Screw hole; 701. Pitch motor main shaft; 702. First resolver rotor; 703. Second resolver rotor; 704. Fixed screw; 705. Resolver rotor pressing plate. DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention will be further described below in conjunction with the drawings and embodiments:

[0028] Embodiment: A double resolver transition shaft connection structure

[0029] Please refer to Attached Figure 1 , A double resolver transition shaft connection structure includes a pitch motor main shaft 701 and a first resolver rotor 702 and a second resolver rotor 703 coaxially arranged with the pitch motor main shaft 701; it further includes a transition shaft 1, and the transition shaft 1 is positioned and connected to one end of the pitch motor main shaft 701 to fix the first resolver rotor 702 and the second resolver rotor 703.

[0030] As Figures 2 to 4 Shown, the transition shaft 1 includes a screw section 2, a first radial positioning section 3, a locking section 4 and a second radial positioning section 5 that are sequentially positioned and connected along the axial direction. Among them, the screw section 2, the first radial positioning section 3 and the second radial positioning section 5 are rotating body structures and are coaxially arranged with the pitch motor main shaft 701 in the assembled state; the diameter of the screw section 2 is smaller than the diameter of the first radial positioning section 3, and the diameters of the first radial positioning section 3 and the second radial positioning section 5 are both smaller than the diameter of the locking section 4.

[0031] One end of the transition shaft 1 on one side of the second radial positioning section 5 is also provided with an axial screw hole 6, and the screw hole 6 is coaxially arranged with the pitch-changing motor main shaft 701; the screw hole 6 and the screw section 2 of the transition shaft 1 have the same thread rotation mode; the transition shaft connection structure further includes a fixing screw 704 arranged in cooperation with the screw hole 6, and a resolver rotor pressing plate 705 threadedly sleeved on the outer periphery of the fixing screw 704. The torque required to lock the screw section 2 of the transition shaft 1 is greater than the torque required to lock the fixing screw 704.

[0032] Combined with Figure 1 As shown, in the assembled state, the screw section 2 is threadedly connected to one end of the pitch-changing motor main shaft 701; one axial end of the first resolver rotor 702 is sleeved on the outer periphery of the first radial positioning section 3, and the other end is sleeved on the end of the connecting screw section 2 of the pitch-changing motor main shaft 701, so that the first resolver rotor 702 is coaxially arranged with the pitch-changing motor main shaft 701; the end face of the locking section 4 on one side of the first radial positioning section 3 is in press-fit with the corresponding end face of the first resolver rotor 702; one axial end of the second resolver rotor 703 is sleeved on the second radial positioning section 5, and the other end is sleeved on the outer periphery of one end of the resolver rotor pressing plate 705; the screw hole 6 is threadedly connected to the fixing screw 704 and the resolver rotor pressing plate 705 respectively; the end face of the locking section 4 on one side of the second radial positioning section 5 is in press-fit with the corresponding end face of the second resolver rotor 703.

[0033] Combined with Figure 1 As shown, in the assembled state, the screw section 2 is divided into a thread-fitting section 201 and an external section 202. The length of the external section 202 is 1.5 times the diameter of the screw section 2. The length of the thread-fitting section 201 is 2 times the diameter of the screw section 2.

[0034] Combined with Figures 3 to 5 As shown, in this embodiment, on one side of the locking section 4 close to the first radial positioning section 3 is a baffle part 401, and on the other side is a platform part 402, and the locking platforms 4021 are all arranged on the platform part 402; the baffle part 401 and the platform part 402 are fixedly connected; the distance from the outer periphery of the platform part 402 to the axis is less than the diameter of the baffle part 401.

[0035] As Figure 5 shown, in this embodiment, there are four locking platforms 4021 arranged axially on the locking section 4; in the cross-section, the four locking platforms 4021 are centrally symmetrically arranged with the axis as the reference and are located on a square centered on the axis.

[0036] The following is an explanation of other implementation cases and structural changes of the present invention:

[0037] 1. In the above embodiments, in the assembled state, except for the threaded mating section, an external section is left on the screw section. This is because there are inevitable coaxiality accuracy errors between the various sections of the transition shaft. The setting of the external section can reduce the stress concentration caused by the concentricity difference between the locking section and the first radial positioning section through elastic mating, and weaken the negative impact of the concentricity difference on the entire shaft structure. However, the assembly method of the screw section in the present invention is not limited to this. Even if there is no external section, the basic technical problems can still be solved, but the technical effect is not the best, which is easily understood and accepted by those skilled in the art.

[0038] 2. In the above embodiments, four locking platforms are provided axially on the locking section, but the number of locking platforms in the present invention is not limited to this. As long as the number of locking platforms is greater than or equal to two, the basic function of locking can be achieved. This is easily understood and accepted by those skilled in the art.

[0039] The above embodiments are only used to illustrate the technical concept and characteristics of the present invention, and their purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A double resolver transition shaft connection structure, comprising a pitch motor main shaft (701), a first resolver rotor (702) and a second resolver rotor (703) coaxially arranged with the pitch motor main shaft (701), characterized in that: It further includes a transition shaft (1) which is positioned and connected to one end of the pitch motor main shaft (701) for fixing the first resolver rotor (702) and the second resolver rotor (703). The transition shaft (1) includes a screw segment (2), a first radial positioning segment (3), a locking segment (4) and a second radial positioning segment (5) which are sequentially positioned and connected along the axial direction. Among them, the screw segment (2), the first radial positioning segment (3) and the second radial positioning segment (5) are of a rotating body structure and are coaxially arranged with the pitch motor main shaft (701) in the assembled state; the diameter of the screw segment (2) is smaller than that of the first radial positioning segment (3), and the diameters of the first radial positioning segment (3) and the second radial positioning segment (5) are both smaller than that of the locking segment (4). One end of the transition shaft (1) on the side of the second radial positioning segment (5) is also provided with an axial screw hole (6) which is coaxially arranged with the pitch motor main shaft (701); the screw hole (6) has the same thread rotation mode as the screw segment (2) of the transition shaft (1); the transition shaft connection structure further includes a fixing screw (704) which is arranged in cooperation with the screw hole (6), and a resolver rotor pressing plate (705) which is threadedly sleeved on the outer periphery of the fixing screw (704). At least two locking platforms (4021) are axially arranged on the locking segment (4). In the assembled state, the screw segment (2) is threadedly connected to one end of the pitch motor main shaft (701); one axial end of the first resolver rotor (702) is sleeved on the outer periphery of the first radial positioning segment (3), and the other end is sleeved on the end of the connecting screw segment (2) of the pitch motor main shaft (701) to make the first resolver rotor (702) coaxially arranged with the pitch motor main shaft (701); the end face of the locking segment (4) on the side of the first radial positioning segment (3) is in press-fit with the corresponding end face of the first resolver rotor (702); one axial end of the second resolver rotor (703) is sleeved on the second radial positioning segment (5), and the other end is sleeved on the outer periphery of one end of the resolver rotor pressing plate (705); the screw hole (6) is threadedly connected to the fixing screw (704) and the resolver rotor pressing plate (705) respectively; the end face of the locking segment (4) on the side of the second radial positioning segment (5) is in press-fit with the corresponding end face of the second resolver rotor (703).

2. The double resolver transition shaft connection structure according to claim 1, characterized in that: In the assembled state, the screw segment (2) is divided into a thread fitting segment (201) and an external segment (202).

3. The double resolver transition shaft connection structure according to claim 2, characterized in that: The length of the external segment (202) is 1 to 2 times the diameter of the screw segment (2).

4. The double resolver transition shaft connection structure according to claim 2, characterized in that: The length of the thread fitting segment (201) is 1.5 to 2.5 times the diameter of the screw segment (2).

5. The double resolver transition shaft connection structure according to any one of claims 1 to 4, characterized in that: On one side of the locking section (4) close to the first radial positioning section (3) is a baffle portion (401), and on the other side is a platform portion (402). The locking platforms (4021) are all arranged on the platform portion (402); the baffle portion (401) and the platform portion (402) are fixedly connected; the distance from the outer circumference of the platform portion (402) to the axis is less than the diameter of the baffle portion (401).

6. The double resolver transition shaft connection structure according to claim 5, characterized in that: The platform portion (402) includes four locking platforms (4021). In the cross-section, these four locking platforms (4021) are symmetrically arranged with respect to the axis as the reference, and are located on a square centered on the axis.

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