A three-phase synchronous generator stator winding phase sequence detection tool and a detection method thereof

Abstract

The application discloses a kind of three-phase synchronous generator stator winding phase sequence detection tool and its detection method, including handle and squirrel cage strip being arranged in motor stator, squirrel cage strip is rotatably arranged on handle by bearing, and U-phase winding, V-phase winding and W-phase winding are arranged on stator core;The present application is provided with squirrel cage strip and handle that squirrel cage strip is rotatably arranged by bearing, and three-phase alternating current is connected to U-phase winding, V-phase winding and W-phase winding, so that rotating magnetic field is generated between motor stator and squirrel cage strip, induced current is generated by the magnetic field cutting of squirrel cage strip, electromagnetic force is generated under the action of rotating magnetic field, and squirrel cage strip rotates on handle, and the phase sequence of three-phase synchronous generator stator winding is judged according to the rotating direction of squirrel cage strip, without artificially judging the phase sequence of three-phase synchronous generator stator winding, the phase sequence detection tool is simple in structure, convenient to operate and use, reduce phase sequence detection cost, improve the phase sequence detection efficiency of three-phase synchronous generator stator winding.

Description

Technical Field

[0001] This invention belongs to the field of stator winding phase sequence detection technology, specifically relating to a three-phase synchronous generator stator winding phase sequence detection fixture and its detection method. Background Technology

[0002] The stator is an important component of motors such as generators and starters. It is an important part of the motor and consists of three parts: the stator core, the stator windings, and the frame. The main function of the stator is to generate a rotating magnetic field, while the main function of the rotor is to be cut by magnetic lines of force in the rotating magnetic field to generate (output) current.

[0003] The determination of whether the phase sequence or magnetic field rotation direction of the generator stator winding is correct is related to the power supply phase sequence. After the generator stator winding is assembled, it is necessary to determine the position sequence of the U, V, and W three-phase windings. The phase sequence of the existing three-phase synchronous generator stator windings is mostly determined manually or by using a phase sequence detection system. Manual determination of the phase sequence is prone to errors, while the phase sequence detection system is expensive, complex in principle and operation, and inconvenient to use. Therefore, we propose a three-phase synchronous generator stator winding phase sequence detection fixture and its detection method. Summary of the Invention

[0004] The purpose of this invention is to provide a three-phase synchronous generator stator winding phase sequence detection fixture and detection method to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a three-phase synchronous generator stator winding phase sequence detection fixture, comprising a handle and a squirrel cage bar disposed inside the motor stator, wherein the squirrel cage bar is rotatably disposed on the handle via a bearing, the motor stator comprising a motor frame and a stator core disposed inside the motor frame, wherein the stator core is provided with U-phase windings, V-phase windings and W-phase windings distributed at equal intervals;

[0006] When the U-phase winding, the V-phase winding, and the W-phase winding are connected to three-phase AC power, a rotating magnetic field is generated between the motor stator and the squirrel cage bars. This magnetic field cuts the squirrel cage bars, generating an induced current. Under the action of the rotating magnetic field, the squirrel cage bars generate electromagnetic force, causing them to rotate on the handle via the bearing. The phase sequence of the three-phase synchronous generator stator winding is determined based on the rotation direction of the squirrel cage bars.

[0007] Preferably, the cage bar includes a bearing collar and a metal strip disposed on the bearing collar;

[0008] The metal strip is a U-shaped metal strip, there are two bearing collars, and at least three metal strips are provided. The openings of the at least three metal strips are arranged in a circular array at both ends on the outer periphery of the two bearing collars.

[0009] Preferably, the cross-section of the metal strip is a solid tube structure, and the metal strip is fixedly connected to the bearing collar by welding.

[0010] Preferably, the metal strip is an aluminum strip.

[0011] Preferably, the bearing is disposed within the bearing collar, the handle is inserted into the bearing, and the length of the handle is greater than the length of the cage bar.

[0012] Preferably, the grip portion of the handle is covered with insulating rubber.

[0013] Preferably, the U-phase winding, the V-phase winding, and the W-phase winding are spatially separated by 120° electrical angles.

[0014] A method for detecting the phase sequence of a three-phase synchronous generator stator winding using a testing fixture, comprising the following steps:

[0015] A: During testing, first connect the variable three-phase AC power supply to the U-phase winding, V-phase winding and W-phase winding on the motor stator, and connect the three-phase AC power supply to the U-phase winding, V-phase winding and W-phase winding to energize the motor stator;

[0016] B: At this time, a rotating magnetic field is generated in the air gap between the motor stator and the squirrel cage bars. This rotating magnetic field will cut the metal bars on the squirrel cage bars, thereby generating an induced current on the surface of the metal bars. The metal bars carrying the induced current generate electromagnetic force under the action of the rotating magnetic field, causing the squirrel cage bars to rotate on the handle through the bearing.

[0017] C: Then, the phase sequence of the stator winding of the three-phase synchronous generator is determined according to the rotation direction of the squirrel cage bars and the direction of the rotating magnetic field between the motor stator and the squirrel cage bars. The direction of the rotating magnetic field between the motor stator and the squirrel cage bars is determined by the phase sequence of the variable three-phase AC power supply connected to the motor stator.

[0018] D: When the rotation direction of the squirrel cage bars is the same as the required direction of the three-phase synchronous generator, the phase sequence of the stator winding of the three-phase synchronous generator is correct; when the rotation direction of the squirrel cage bars is different from the required direction of the three-phase synchronous generator, the phase sequence of the stator winding of the three-phase synchronous generator is incorrect.

[0019] E: When the phase sequence of the stator winding of the three-phase synchronous generator is incorrect, it is necessary to arbitrarily swap the phase sequence of the variable three-phase AC power supply connected to two of the U-phase winding, V-phase winding and W-phase winding on the stator of the generator, and then repeat steps AD until the phase sequence of the stator winding of the three-phase synchronous generator is correct.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] This invention features a squirrel cage bar comprising a bearing collar and metal strips, and a handle that rotates the squirrel cage bar via the bearing. Three-phase AC power is connected to the U-phase, V-phase, and W-phase windings of the motor stator, generating a rotating magnetic field between the motor stator and the squirrel cage bar. This magnetic field cuts the squirrel cage bar, inducing a current. Under the influence of the rotating magnetic field, the squirrel cage bar generates electromagnetic force, causing it to rotate via the handle. The phase sequence of the three-phase synchronous generator stator windings is determined based on the direction of rotation of the squirrel cage bar. This eliminates the need for manual phase sequence determination. Furthermore, this phase sequence detection fixture has a simple structure, is easy to operate, reduces phase sequence detection costs, and improves the efficiency of three-phase synchronous generator stator winding phase sequence detection. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0023] Figure 2 This is a three-dimensional structural diagram of the present invention;

[0024] Figure 3 This is a schematic diagram of the main structure of the present invention;

[0025] Figure 4 This is a partial three-dimensional structural schematic diagram of the present invention.

[0026] In the diagram: 1. Motor stator; 101. Motor frame; 102. Stator core; 103. U-phase winding; 104. V-phase winding; 105. W-phase winding; 2. Handle; 3. Squirrel cage bar; 301. Bearing collar; 302. Metal strip; 4. Bearing; 5. Insulating rubber. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] Please see Figures 1-4The present invention provides a three-phase synchronous generator stator winding phase sequence detection fixture, comprising a handle 2 and a squirrel cage bar 3 disposed within the motor stator 1. The squirrel cage bar 3 is rotatably mounted on the handle 2 via a bearing 4. The squirrel cage bar 3 includes a bearing collar 301 and a metal strip 302 disposed on the bearing collar 301. The metal strip 302 is a U-shaped metal strip. There are two bearing collars 301 and at least three metal strips 302. The openings of the at least three metal strips 302 are arranged in a circular array at both ends, respectively disposed on the outer periphery of two bearing collars 301. The cross-section of the metal strip 302 is a solid tube structure, and the metal strip 302 is connected to the bearing collar 301. The bearing collar 301 is fixedly connected by welding. The metal strip 302 is an aluminum strip. The bearing 4 is set inside the bearing collar 301. The handle 2 is inserted into the bearing 4. The length of the handle 2 is greater than the length of the squirrel cage bar 3. The grip part on the handle 2 is wrapped with insulating rubber 5. The motor stator 1 includes a motor frame 101 and a stator core 102 set inside the motor frame 101. The stator core 102 is provided with U-phase windings 103, V-phase windings 104 and W-phase windings 105 that are evenly distributed. The U-phase windings 103, V-phase windings 104 and W-phase windings 105 are spatially 120° electrical angle apart.

[0029] When the U-phase winding 103, V-phase winding 104, and W-phase winding 105 are connected to three-phase AC power, a rotating magnetic field is generated between the motor stator 1 and the squirrel cage bar 3. This magnetic field cuts the squirrel cage bar 3, generating an induced current. Under the action of the rotating magnetic field, the squirrel cage bar 3 generates electromagnetic force, causing it to rotate on the handle 2 via the bearing 4. The phase sequence of the three-phase synchronous generator stator winding is determined based on the rotation direction of the squirrel cage bar 3.

[0030] This invention features a squirrel cage bar 3 including a bearing collar 301 and a metal strip 302, and a handle 2 that rotates the squirrel cage bar 3 via a bearing 4. Three-phase AC power is connected to the U-phase winding 103, V-phase winding 104, and W-phase winding 105 on the motor stator 1, generating a rotating magnetic field between the motor stator 1 and the squirrel cage bar 3. This magnetic field cuts the squirrel cage bar 3, generating an induced current. Under the influence of the rotating magnetic field, the squirrel cage bar 3 generates electromagnetic force, causing it to rotate via the bearing 4 on the handle 2. The phase sequence of the three-phase synchronous generator stator windings is determined based on the rotation direction of the squirrel cage bar 3. This eliminates the need for manual phase sequence determination. Furthermore, this phase sequence detection fixture has a simple structure, is easy to operate, reduces phase sequence detection costs, and improves the efficiency of three-phase synchronous generator stator winding phase sequence detection.

[0031] The detection method for the phase sequence detection fixture of the stator winding of a three-phase synchronous generator provided by the present invention includes the following steps:

[0032] A: During testing, first connect the U-phase winding 103, V-phase winding 104 and W-phase winding 105 on the motor stator 1 through a variable three-phase AC power supply, and connect the three-phase AC power supply to the U-phase winding 103, V-phase winding 104 and W-phase winding 105 to energize the motor stator 1.

[0033] B: At this time, a rotating magnetic field is generated in the air gap between the motor stator 1 and the squirrel cage bar 3. This rotating magnetic field will cut the metal bar 302 on the squirrel cage bar 3, thereby generating an induced current on the surface of the metal bar 302. The metal bar 302 carrying the induced current generates an electromagnetic force under the action of the rotating magnetic field, causing the squirrel cage bar 3 to rotate on the handle 2 through the bearing 4.

[0034] C: Then, the phase sequence of the stator winding of the three-phase synchronous generator is determined according to the rotation direction of the squirrel cage bar 3 and the direction of the rotating magnetic field between the motor stator 1 and the squirrel cage bar 3. The direction of the rotating magnetic field between the motor stator 1 and the squirrel cage bar 3 is determined by the phase sequence of the variable three-phase AC power supply connected to the motor stator 1.

[0035] D: When the rotation direction of the squirrel cage bar 3 is the same as the required direction of the three-phase synchronous generator, the phase sequence of the stator winding of the three-phase synchronous generator is correct; when the rotation direction of the squirrel cage bar 3 is different from the required direction of the three-phase synchronous generator, the phase sequence of the stator winding of the three-phase synchronous generator is incorrect.

[0036] E: When the phase sequence of the stator winding of the three-phase synchronous generator is incorrect, it is necessary to arbitrarily swap the phase sequence of the variable three-phase AC power supply connected to two of the windings of the U-phase winding 103, V-phase winding 104 and W-phase winding 105 on the stator 1 of the generator, and then repeat steps AD until the phase sequence of the stator winding of the three-phase synchronous generator is correct.

[0037] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fixture for detecting the phase sequence of the stator winding of a three-phase synchronous generator, characterized in that, The motor stator (1) includes a handle (2) and a squirrel cage bar (3) disposed inside the motor stator (1). The squirrel cage bar (3) is rotatably disposed on the handle (2) via a bearing (4). The motor stator (1) includes a motor frame (101) and a stator core (102) disposed inside the motor frame (101). The stator core (102) is provided with U-phase windings (103), V-phase windings (104) and W-phase windings (105) distributed at equal intervals. When the U-phase winding (103), the V-phase winding (104) and the W-phase winding (105) are connected to three-phase AC power, a rotating magnetic field is generated between the motor stator (1) and the squirrel cage bar (3), and the magnetic field cuts the squirrel cage bar (3) to generate an induced current, so that the squirrel cage bar (3) generates electromagnetic force under the action of the rotating magnetic field, causing the squirrel cage bar (3) to rotate on the handle (2) through the bearing (4), and the phase sequence of the stator winding of the three-phase synchronous generator is determined according to the rotation direction of the squirrel cage bar (3). The cage bar (3) includes a bearing collar (301) and a metal bar (302) disposed on the bearing collar (301). The metal strip (302) is a U-shaped metal strip. There are two bearing collars (301) and at least three metal strips (302). The openings of the at least three metal strips (302) are arranged in a circular array on the outer periphery of the two bearing collars (301). The U-phase winding (103), the V-phase winding (104), and the W-phase winding (105) are spatially separated by an electrical angle of 120°.

2. The three-phase synchronous generator stator winding phase sequence detection fixture according to claim 1, characterized in that: The cross-section of the metal strip (302) is a solid tube structure, and the metal strip (302) and the bearing collar (301) are fixedly connected by welding.

3. The three-phase synchronous generator stator winding phase sequence detection fixture according to claim 2, characterized in that: The metal strip (302) is an aluminum strip.

4. The three-phase synchronous generator stator winding phase sequence detection fixture according to claim 1, characterized in that: The bearing (4) is disposed inside the bearing collar (301), and the handle (2) is inserted into the bearing (4). The length of the handle (2) is greater than the length of the cage bar (3).

5. The three-phase synchronous generator stator winding phase sequence detection fixture according to claim 4, characterized in that: The grip portion of the handle (2) is covered with insulating rubber (5).

6. A detection method for a three-phase synchronous generator stator winding phase sequence detection fixture according to any one of claims 1-5, characterized in that, Includes the following steps: A: During testing, first connect the U-phase winding (103), V-phase winding (104) and W-phase winding (105) on the motor stator (1) through a variable three-phase AC power supply, and connect the three-phase AC power supply to the U-phase winding (103), V-phase winding (104) and W-phase winding (105) to energize the motor stator (1); B: At this time, a rotating magnetic field is generated in the air gap between the motor stator (1) and the squirrel cage bar (3). This rotating magnetic field will cut the metal bar (302) on the squirrel cage bar (3), thereby generating an induced current on the surface of the metal bar (302). The metal bar (302) carrying the induced current generates an electromagnetic force under the action of the rotating magnetic field, causing the squirrel cage bar (3) to rotate on the handle (2) through the bearing (4). C: Then, the phase sequence of the stator winding of the three-phase synchronous generator is determined according to the rotation direction of the squirrel cage bar (3) and the direction of the rotating magnetic field between the motor stator (1) and the squirrel cage bar (3). The direction of the rotating magnetic field between the motor stator (1) and the squirrel cage bar (3) is determined by the phase sequence of the variable three-phase AC power supply connected to the motor stator (1). D: When the rotation direction of the squirrel cage bar (3) is the same as the required direction of the three-phase synchronous generator, the phase sequence of the stator winding of the three-phase synchronous generator is correct; when the rotation direction of the squirrel cage bar (3) is different from the required direction of the three-phase synchronous generator, the phase sequence of the stator winding of the three-phase synchronous generator is incorrect. E: When the phase sequence of the stator winding of the three-phase synchronous generator is incorrect, it is necessary to arbitrarily change the phase sequence of the variable three-phase AC power supply connected to two of the windings of the U-phase winding (103), V-phase winding (104) and W-phase winding (105) on the stator (1) of the generator, and then repeat steps AD until the phase sequence of the stator winding of the three-phase synchronous generator is correct.

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