Measurement device for minimum torque point of double-skewed-slot equal-slot matched induction motor

Abstract

The invention discloses a measuring device for a minimum torque point of a double-chute equal-slot cooperation induction motor, and relates to the technical field of motor starting torque measurement. The fluted disc is arranged on the side face of the coupler, and different skewed slot degrees are finely divided through the fluted disc; the skewed slot degree display mechanism is in transmission connection with the coupler, when different slots are matched with the rotor to rotate relative to the stator, the coupler and the rotor rotate synchronously, and the skewed slot degree display mechanism can display the skewed slot degree according to the rotation angle of the rotor. The skewed slot degree between the stator and the rotor is visually displayed through the skewed slot degree display mechanism, when the rotor rotates to change the skewed slot degree, the corresponding skewed slot degree can be recorded through the skewed slot degree display mechanism, and starting torques corresponding to different skewed slot degrees can be obtained after torque is detected through starting torque measuring equipment. Therefore, the minimum torque point of the induction motor is found, and the problem that the induction motor cannot be started due to too small torque is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of motor starting torque measurement, in particular to a device for measuring the minimum torque point of a double-slot equal-slot matching induction motor. Background Art

[0002] Induction motors are widely used in various electrical transmission systems due to their excellent characteristics. The output torque of an induction motor is related to the starting position of the motor. An equal-slot induction motor can be started under a double-beveled slot structure, but when the motor is at one or more starting positions, its maximum starting torque is much smaller than other starting positions, so it is necessary to avoid starting the motor at this minimum torque point during operation. Different starting positions refer to different relative positions of the stator and the rotor. Because the stator and the rotor are symmetrical circular structures, and each stator slot and rotor slot are the same size, the starting position can be represented by the relative position (bevel degree) of a stator slot and a rotor slot.

[0003] Generally, the method for measuring the starting torque of a motor is to measure it directly through a dynamometer, or to measure it indirectly based on the calculation method of electrical parameters. Midea Welling Motor Technology (Shanghai) Co., Ltd. has publicly invented a method, device and motor control system for measuring the starting torque of a motor (CN106330047 A), which controls the rotor to be stationary in the first position by presetting a first voltage vector, and collects the current data at this time. Then rotate the rotor to the second position of the preset second voltage vector, repeat the operation to obtain the current at the second position, and calculate the starting torque of the motor based on the phase difference between the two times. Although this method is simple to operate and has low measurement cost, this method sets the starting position of the rotor from the perspective of voltage, and is not refined. For induction motors with double inclined slots and equal slots, it is impossible to accurately locate the position of the minimum torque point.

[0004] In view of this, how to provide a device capable of measuring the minimum torque point of a double-beveled slot equal-slot matched induction motor is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0005] The stator and rotor of the induction motor both have 36 slots. On this basis, the purpose of the present invention is to provide a device for accurately measuring the minimum torque of a double-skewed slot induction motor to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides the following solution: The present invention provides a device for measuring the minimum torque point of an induction motor with double skew slots and equal slots, comprising:

[0007] The toothed disc is arranged on the side of the coupling and is used to divide the different degrees of the bevel groove;

[0008] A coupling, fixedly connected to the transmission shaft of the rotor;

[0009] A skew degree display mechanism is drivingly connected to the coupling. When the rotor rotates relative to the stator, the coupling rotates synchronously with the rotor. The skew degree display mechanism can display the skew degree according to the rotation angle of the rotor.

[0010] Furthermore, the skew degree display mechanism comprises:

[0011] A telescopic rod, fixedly connected to the end surface of the coupling;

[0012] A vertical ruler is vertically arranged on one side of the telescopic rod and is slidably connected to the output end of the telescopic rod; the rotor can rotate relative to the stator between a first angle and a second angle; the arc between the first angle and the second angle is evenly divided into multiple rotation intervals, and the vertical ruler is provided with scale lines corresponding to the multiple rotation intervals. When the rotor rotates to a rotation interval, the output end of the telescopic rod slides to the corresponding scale position.

[0013] Furthermore, the output end of the telescopic rod is hinged to a sliding connection piece through a buckle, and the sliding connection piece is sleeved on the vertical ruler.

[0014] Furthermore, a threaded hole is provided on the telescopic rod, a magnetic seat is provided in the threaded hole, and the telescopic rod is fixed to the end face of the coupling through the magnetic seat.

[0015] Furthermore, the scale lines are non-uniform scale lines. When the center lines of the stator and the rotor coincide, the output end of the telescopic rod is located at the scale position 0, and the scale lines are densely distributed in the area close to the scale position 0 and sparsely distributed in the area away from the scale position 0.

[0016] Furthermore, it also includes a base plate, the stator is located in a stator shell, the stator shell is fixed on the base plate by fastening bolts, and the vertical ruler has a base, and the base is fixedly connected to the base plate.

[0017] The present invention discloses the following technical effects:

[0018] The skew degree between the stator and the rotor is intuitively displayed through the skew degree display mechanism. When the rotor rotates to change the skew degree, the corresponding skew degree can be recorded through the skew degree display mechanism. After the torque is detected by the starting torque measuring equipment, the starting torque corresponding to different skew degrees can be obtained, and the skew degree corresponding to the optimal starting torque can also be confirmed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 is the stator slot distribution diagram;

[0021] Figure 2 It is a schematic diagram of the structure of the present invention;

[0022] Figure 3 This is a schematic diagram of the cooperation between the present invention and the motor;

[0023] Figure 4 for Figure 3 Top view;

[0024] Among them, 1. stator housing; 2. first fastening bolt; 3. second fastening bolt; 4. third fastening bolt; 5. fourth fastening bolt; 6. motor bearing seat; 7. coupling; 8. transmission shaft; 9. first magnetic seat; 10. second magnetic seat; 11. telescopic rod; 12. vertical ruler; 13. buckle; 14. base; 15. sliding connector; 16. base plate; 17. first threaded hole; 18. second threaded hole; 19. gear disc. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] The embodiment of the present invention provides a device for measuring the minimum torque point of an induction motor with double skew slots and equal slots, comprising: a coupling 7, fixedly connected to a transmission shaft 8 of a rotor; a toothed disc arranged on the side of the coupling 7, used to divide different skew slot degrees, the toothed disc has 360 teeth, the stator and rotor of the induction motor both have 36 slots, 10 teeth to 1 slot, so that a stator slot can be evenly divided into ten angles. A skew slot display mechanism, the skew slot display mechanism is connected to the coupling 7 in a transmission manner, when the rotor rotates relative to the stator, the coupling 7 rotates synchronously with the rotor, and the skew slot display mechanism can display the skew slot degree according to the rotation angle of the rotor.

[0028] The skew degree display mechanism includes a telescopic rod 11 and a vertical ruler 12; the telescopic rod 11 is made of a material with a certain hardness and is a three-section telescopic rod 11. Two threaded holes are provided on the left side of the telescopic rod 11, namely a first threaded hole 17 and a second threaded hole 18. A first magnetic seat 9 is provided in the first threaded hole 17, and a second magnetic seat 10 is provided in the second threaded hole 18. The telescopic rod 11 is fixed to the end face of the coupling 7 by adsorption through the two magnetic seats. The vertical ruler 12 is vertically arranged on one side of the telescopic rod 11 and is slidably connected to the output end of the telescopic rod 11; the rotor can rotate relative to the stator between the first angle and the second angle; the arc between the first angle and the second angle is evenly divided into a plurality of rotation intervals, and the vertical ruler 12 is provided with scale lines corresponding to the plurality of rotation intervals. When the rotor rotates to a rotation interval, the output end of the telescopic rod 11 slides to the corresponding scale position.

[0029] In this embodiment, both the vertical ruler 12 and the toothed disc 19 can display the skewness, wherein the main function of the vertical ruler 12 is to intuitively display the skewness, while the purpose of the toothed disc 19 is to divide the 36 slots of the stator and rotor into more detailed areas to facilitate the precise positioning of the minimum torque point.

[0030] In this embodiment, the output end of the telescopic rod 11 is hinged to the sliding connector 15 through the buckle 13, and the sliding connector 15 is sleeved on the vertical ruler 12. The scale lines are non-uniform scale lines. When the center lines of the stator and the rotor coincide, the output end of the telescopic rod 11 is located at the scale position 0, and the scale lines are dense in the area close to the scale position 0, and sparse in the area away from the scale position 0. When measuring, fix the telescopic rod 11 according to actual conditions, record the length a of the telescopic rod 11 when it is parallel, slide the telescopic rod 11 to a certain angle, record the angle between the telescopic rod 11 and the horizontal as α, and the vertical ruler scale is atanα.

[0031] In this embodiment, a base plate 16 is also included. The stator is located in the stator housing 1. The stator housing 1 is fixed on the base plate 16 by fastening bolts. Specifically, the stator housing 1 is located on the motor bearing seat 6. The first fastening bolt 2, the second fastening bolt 3, the third fastening bolt 4 and the fourth fastening bolt 5 are symmetrically arranged on both sides of the motor bearing seat 6. The vertical ruler 12 has a base 14. A suction cup is provided below the base 14, which can be fixed on the base plate 16 by suction.

[0032] The method of using this embodiment is as follows:

[0033] Figure 1 The figure shows the schematic diagram of stator slot distribution. Figure 2 for Figure 1 A partial structural enlargement diagram of Figure 2 The stator slots at the middle angle A1 - angle A2 are used as the refinement objects of the angular interval, and this embodiment divides them into ten angular regions.

[0034] The telescopic rod 11 is horizontally arranged and fixed on the coupling 7 by the first magnetic base 9 and the second magnetic base 10. Figure 4 As shown, at this time, the output end of the telescopic rod 11 corresponds to the scale of the vertical ruler 12 at position 0. The starting torque measuring device is connected to the motor. The starting torque measuring device can be an existing device, which will not be described in detail here.

[0035] Start the motor, measure the current, voltage and other parameters corresponding to the 0 position of the scale, calculate the corresponding starting torque starting value and maximum value, etc.

[0036] Turn off the motor, move the sliding connector 15 to the position where the vertical ruler 12 is marked with a scale of 1, and the output end of the telescopic rod 11 moves upward. Figure 4 The right side of the rotor is extended for a distance. At this time, the rotor rotates upward relative to the stator by an arc of an angular region (the first of the ten angular regions mentioned above). The current, voltage and other parameters corresponding to the position of scale 1 are measured, and the corresponding starting torque starting value and maximum value, etc. are calculated.

[0037] Repeat the above steps until the starting values ​​and maximum values ​​of the starting torques corresponding to the ten corner regions are all calculated, and the optimal starting torque and the corresponding skew degree can be obtained by comparative analysis.

[0038] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0039] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A device for measuring the minimum torque point of a double-slot equal-slot induction motor, characterized in that: include: A coupling (7) fixedly connected to a transmission shaft (8) of the rotor; A toothed disc, arranged on the side of the coupling (7), for dividing different degrees of bevel groove; A skew degree display mechanism is drivingly connected to the coupling (7). When the rotor rotates relative to the stator, the coupling (7) rotates synchronously with the rotor. The skew degree display mechanism can display the skew degree according to the rotation angle of the rotor.

2. The device for measuring the minimum torque point of a double-slot equal-slot induction motor according to claim 1, characterized in that: The chute degree display mechanism comprises: A telescopic rod (11) fixedly connected to the end surface of the coupling (7); A vertical ruler (12) is vertically arranged on one side of the telescopic rod (11) and is slidably connected to the output end of the telescopic rod (11); the rotor can rotate relative to the stator between a first angle and a second angle; the arc between the first angle and the second angle is evenly divided into a plurality of rotation intervals, and the vertical ruler (12) is provided with scale lines corresponding to the plurality of rotation intervals; when the rotor rotates to a rotation interval, the output end of the telescopic rod (11) slides to a corresponding scale position.

3. The device for measuring the minimum torque point of a double-slot equal-slot induction motor according to claim 2, characterized in that: The output end of the telescopic rod (11) is hinged to a sliding connection piece (15) via a buckle (13), and the sliding connection piece (15) is sleeved on the vertical ruler (12).

4. The device for measuring the minimum torque point of a double-slot equal-slot induction motor according to claim 2, characterized in that: The telescopic rod (11) is provided with a threaded hole, a magnetic seat is provided in the threaded hole, and the telescopic rod (11) is fixed to the end surface of the coupling (7) via the magnetic seat.

5. The device for measuring the minimum torque point of a double-slot equal-slot induction motor according to claim 2, characterized in that: The scale lines are non-uniform scale lines. When the center lines of the stator and the rotor coincide, the output end of the telescopic rod (11) is located at the scale position 0. The scale lines are dense in the area close to the scale position 0 and sparse in the area away from the scale position 0.

6. The device for measuring the minimum torque point of a double-slot equal-slot induction motor according to claim 2, characterized in that: It also comprises a base plate (16), the stator is located in the stator housing (1), the stator housing (1) is fixed on the base plate (16) by means of fastening bolts, and the vertical ruler (12) has a base (14), and the base (14) is fixedly connected to the base plate (16).

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