Three-phase motor stator winding maintenance quality detection device

Abstract

The utility model belongs to the technical field of motors, and particularly relates to a three-phase motor stator winding maintenance quality detection device which comprises a power supply, a voltage regulator, a current transformer and an ampere meter. A terminal outgoing line of a motor winding to be tested penetrates through an iron core coil of the current transformer and then is connected with the output end of a voltage regulator, and the input end of the voltage regulator is connected with a power supply; a wiring terminal of the current transformer is connected with the ampere meter; the voltage regulator is used for applying voltages with different amplitudes to the to-be-measured motor winding, and the ampere meter is used for measuring the current, converted by the current transformer, of the to-be-measured motor winding. The detection device provided by the utility model is used for detecting the quality condition of the winding in advance before the motor is assembled, and can detect the winding quality of the winding under the condition that the winding enters a slot only; in other words, winding quality detection is completed in the maintenance process of the motor, the motor does not need to be verified in operation after being assembled, and the time for manual repeated disassembly and assembly and the consumption of insulating materials can be reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of motors, and particularly relates to a device for detecting the repair quality of a stator winding of a three-phase motor. Background Art

[0002] The statements in this part only provide background technical information related to the utility model, and do not necessarily constitute prior art.

[0003] Motors are widely used in various fields that convert electrical energy into mechanical energy in today's era. Given the huge inventory, problems with damaged motor windings caused by various reasons are common. The conventional repair method is to perform insulation treatment on the motor stator after rewinding the winding, and then conduct power-on detection of the three-phase current after reassembly and operation to judge the repair quality.

[0004] Although a large deviation in the three-phase current detected at this time can be used to determine that the repair quality is unqualified, after detecting that the winding is unqualified, it is necessary to disassemble the motor again for detection, and even clean the insulating paint and remove the winding, resulting in repeated labor and material losses and reducing the repair efficiency. Summary of the Utility Model

[0005] To overcome the deficiencies of the above-mentioned prior art, the utility model provides a device for detecting the repair quality of a stator winding of a three-phase motor.

[0006] To achieve the above object, one or more embodiments of the utility model provide the following technical solutions:

[0007] The first aspect of the utility model provides a device for detecting the repair quality of a stator winding of a three-phase motor, including a power supply, a voltage regulator, a current transformer, and an ammeter;

[0008] The lead-out wire of the terminal of the motor winding to be tested passes through the iron core coil of the current transformer and then connects to the output terminal of the voltage regulator, and the input terminal of the voltage regulator connects to the power supply; the wiring terminal of the current transformer is connected to the ammeter;

[0009] The voltage regulator is used to apply voltages with different amplitudes to the motor winding to be tested, and the ammeter is used to measure the current of the motor winding to be tested after being converted by the current transformer.

[0010] Further, the power supply is a three-phase 380V AC power supply.

[0011] Further, a circuit breaker is also connected in series between the power supply and the voltage regulator.

[0012] Further, the ammeter is a digital display ammeter.

[0013] Further, the motor winding to be tested is the stator winding of a three-phase motor after repair.

[0014] Further, the terminal blocks U1, V1, and W1 of the stator winding of the three-phase motor are respectively connected to the output terminals of the corresponding phases of the voltage regulator.

[0015] Further, the current transformer includes a primary-side iron core coil and a secondary-side iron core coil;

[0016] The terminal blocks of the stator winding of the three-phase motor pass through the primary-side iron core coil and then are connected to the voltage regulator; both ends of the secondary-side iron core coil are connected to an ammeter.

[0017] Further, the terminal blocks of the stator winding of the three-phase motor penetrate from the front of the wire-passing hole of the primary-side iron core coil and come out from the back of the wire-passing hole of the primary-side iron core coil.

[0018] Further, the number of the current transformers is 3, and they are respectively arranged on the three-phase terminal blocks of the motor winding to be tested.

[0019] Further, the voltage regulator is provided with a knob for adjusting the voltage value at the output terminal of the voltage regulator.

[0020] The above one or more technical solutions have the following beneficial effects:

[0021] (1) The detection device provided by the present invention is used to detect the quality of the winding in advance before motor assembly, and can detect the winding quality when only the winding is inserted into the slot; that is, the winding quality is detected during the motor repair process, without the need to assemble the motor and verify it during operation, which can reduce the time of manual repeated disassembly and assembly and the consumption of insulating materials.

[0022] (2) The detection device provided by the present invention can directly reflect whether there is an inter-turn short circuit in the winding, and can check whether the currents between the windings of each phase of the motor are balanced, simulating the effect of normal operation of the motor, reducing the rework frequency and lowering the rework rate.

[0023] (3) Considering that the resistance values of the motor windings to be tested are different and it is impossible to accurately determine the input voltage, by setting a voltage regulator, the input voltage amplitude of the motor windings to be tested can be adjusted, playing a role in protecting the motor windings.

[0024] The advantages of the additional aspects of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0025] The attached drawings of the specification, which form a part of the present utility model, are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation of the present utility model.

[0026] Figure 1 It is a schematic diagram of the device for detecting the repair quality of the stator winding of a three-phase motor in Embodiment 1.

[0027] In the figure, 1 is the power supply; 2 is the voltage regulator; 3 is the current transformer; 4 is the ammeter; 5 is the motor winding to be tested. Specific Embodiments

[0028] The present utility model will be further described below in conjunction with the attached drawings and embodiments.

[0029] Embodiment 1

[0030] As Figure 1 shown, the present utility model provides a device for detecting the repair quality of the stator winding of a three-phase motor, including a power supply 1, a voltage regulator 2, a current transformer 3, and an ammeter 4;

[0031] After the lead-out wires of the connection terminals of the motor winding 5 to be tested pass through the iron core coil of the current transformer 3, they are connected to the output terminal of the voltage regulator 2, and the input terminal of the voltage regulator 2 is connected to the power supply 1; the connection terminals of the current transformer 3 are connected to the ammeter 4;

[0032] The voltage regulator 2 is used to apply voltages with different amplitudes to the motor winding to be tested, and the ammeter 4 is used to measure the current of the motor winding 5 to be tested after being converted by the current transformer 3.

[0033] Among them, the motor winding 5 to be tested is the stator winding of a three-phase motor after repair; U1, V1, W1 and U2, V2, W2 are the connection terminals of the stator winding of the motor; among them, U1-U2, V1-V2, W1-W2 respectively correspond to a phase circuit; the connection terminals U1, V1, and W1 of the stator winding of the three-phase motor are respectively connected to the output terminals of the corresponding phases of the voltage regulator 2.

[0034] As a further technical solution, the power supply 1 is a three-phase 380v AC power supply, and a circuit breaker (QS) is also connected in series between the power supply 1 and the voltage regulator 2; the circuit breaker (QS) is used for switching on and off the three-phase power supply 1, and can quickly cut off the circuit when a fault occurs in the circuit to protect the equipment from damage caused by the fault.

[0035] The voltage regulator 2 has three-phase outputs and the output voltage value is adjustable; the three-phase input terminals (R, S, T) of the voltage regulator 2 are respectively connected to the three-phase incoming power supply (L1, L2, L3) through the circuit breaker (QS)

[0036] The voltage regulator 2, as an instrument for applying voltage to the motor winding to be tested, gradually increases the current in the motor winding to the rated current of the motor. The voltage regulator is equipped with a knob, and the voltage amplitude at the output end is gradually adjusted by turning the knob; moreover, before voltage regulation, it should be confirmed that the knob on the voltage regulator 2 is at the 0V position, and the voltage increase process needs to be slow and uniform.

[0037] Due to the different resistances of the motor windings (for motors of the same model, the resistance will also be different due to different lengths of the iron cores), the required input voltage will fluctuate up and down, and it is impossible to accurately determine the input voltage;

[0038] In this embodiment, by setting a voltage regulator to gradually adjust the input voltage of the motor winding to be tested, gradual voltage regulation can ensure that the winding will not be damaged in case of problems with the winding, and when the problem point is too large, it can be detected before reaching the rated current, providing maximum protection for the motor winding.

[0039] The ammeter 4 is a digital display ammeter, and there are three of them, which are respectively connected to the current transformers 3 on the three-phase connection terminals of the motor winding to be tested; the ammeter 4, as a device for measuring the current value of the three-phase motor winding, can measure the current of each group of motor windings simultaneously and display the current value of the motor winding in real time for easy viewing. In this embodiment, the voltage regulator 2, the current transformer 3, and the ammeter 4 are all standard model accessories in the electrical industry, and the specific models are selected according to the actual situation.

[0040] In this embodiment, by checking the value of the ammeter and calculating and comparing whether the current difference between every two phases is less than or equal to 5% of the rated current on the motor nameplate, the quality of the motor winding is judged;

[0041] For example: Suppose the ammeter shows that the current values of the three-phase windings U, V, and W of the motor are 9.8A, 10A, and 9.3A respectively, and the rated current on the motor nameplate is 10A; calculate the current differences pairwise: UV = 0.2A, UW = 0.5A, VW = 0.7A. Since the current difference of the motor winding VW exceeds 5% of the rated current on the motor nameplate, that is, 0.5A, it indicates that there are quality abnormalities in the windings V and W.

[0042] As a further technical solution, corresponding current transformers 3 are respectively set on the three-phase connection terminals of the motor winding to be tested, and the current transformers 3 on each phase are respectively connected to the ammeter 4.

[0043] The current transformer 3 includes a primary side iron core coil and a secondary side iron core coil; the connection terminals of the three-phase motor stator winding pass through the primary side iron core coil and then are connected to the voltage regulator 2; the outgoing terminals S1 and S2 of the current transformer 3 are the connection terminals of the secondary side coil, and both ends of the secondary side iron core coil are connected to the connection terminals of the ammeter 4 with wires.

[0044] Among them, P1 and P2 are the front and back sides of the primary side iron core coil threading hole. The connection terminals of the stator winding of the three-phase motor pass through the front side iron core coil threading hole P1 and pass through the back side iron core coil threading hole P2.

[0045] In this embodiment, a mutual inductor is arranged on the three-phase line of the motor winding to be tested. The mutual inductor on the three phases serves as a signal source of the ammeter to measure the actual current value of each phase winding, which is then received by the ammeter and displayed on the ammeter.

[0046] The workflow of the utility model is:

[0047] S1: Pass the three-phase external leads of the voltage regulator 2 through the iron core coil of the current transformer 3 (in at P1 and out at P2), and then connect them to the winding to be tested of the three-phase motor; the three current transformer 3 output terminals S1 and S2 lead wires are connected to the ammeter 4 respectively, and correspond to the terminals S1 and S2 on the ammeter 4.

[0048] S2: After the voltage regulating knob of voltage regulator 2 is rotated to the 0V position, the power supply 1 of voltage regulator 2 is turned on, and then the voltage of voltage regulator 2 is started to be adjusted; the output voltage value of voltage regulator 2 is gradually increased from 0V until it is adjusted to between ±10% and ±15% of the rated voltage parameter on the motor nameplate corresponding to the three-phase motor winding to be tested.

[0049] S3: Check whether the current value of the three-phase winding displayed by the ammeter 4 has reached the rated current of the motor nameplate; by checking the current value of the three-phase winding displayed by the ammeter 4, compare the current difference between each phase to judge the quality of the motor winding.

[0050] Although the above describes the specific implementation methods of the utility model in combination with the accompanying drawings, it is not intended to limit the scope of protection of the utility model. Technical personnel in the relevant field should understand that on the basis of the technical solution of the utility model, various modifications or deformations that can be made by technical personnel in this field without creative work are still within the scope of protection of the utility model.

Claims

1. A quality inspection device for the maintenance of a three-phase motor stator winding, characterized in that, It includes a power supply, a voltage regulator, a current transformer and an ammeter; After the lead wire of the terminal of the motor winding to be tested passes through the iron core coil of the current transformer, it is connected to the output terminal of the voltage regulator, and the input terminal of the voltage regulator is connected to the power supply; The wiring terminal of the current transformer is connected to the ammeter; The voltage regulator is used to apply voltages with different amplitudes to the motor winding to be tested, and the ammeter is used to measure the current of the motor winding to be tested after being converted by the current transformer.

2. The quality inspection device for the stator winding of a three-phase motor according to claim 1, characterized in that, The power supply is a three-phase 380V AC power supply.

3. The quality inspection device for the stator winding of a three-phase motor according to claim 1, characterized in that A circuit breaker is also connected in series between the power supply and the voltage regulator.

4. A three-phase motor stator winding maintenance quality detection device according to claim 1, characterized in that, The ammeter is a digital display ammeter.

5. A quality inspection device for the stator winding of a three-phase motor according to claim 1, characterized in that, The motor winding to be tested is the stator winding of a three-phase motor after repair.

6. The quality inspection device for the stator winding of a three-phase motor according to claim 5, characterized in that The wiring terminals U1, V1 and W1 of the stator winding of the three-phase motor are respectively connected to the output terminals of the corresponding phases of the voltage regulator.

7. A quality inspection device for the stator winding of a three-phase motor according to claim 1, characterized in that, The current transformer includes a primary side iron core coil and a secondary side iron core coil; The wiring terminal of the stator winding of the three-phase motor is connected to the voltage regulator after passing through the primary side iron core coil; the two ends of the secondary side iron core coil are connected to the ammeter.

8. A quality inspection device for the stator winding of a three-phase motor according to claim 7, characterized in that, The wiring terminal of the stator winding of the three-phase motor passes through the front of the wire passing hole of the primary side iron core coil and exits from the back of the wire passing hole of the primary side iron core coil.

9. A quality inspection device for the repair of a three-phase motor stator winding according to claim 1, characterized in that, The number of current transformers is 3, which are respectively arranged on the three-phase wiring terminals of the motor winding to be tested.

10. A quality inspection device for the stator winding of a three-phase motor according to claim 1, characterized in that, The voltage regulator is provided with a knob, and the knob is used to adjust the voltage value of the output terminal of the voltage regulator.

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