CN114167154A - Phase sequence self-checking motor and phase sequence checking method - Google Patents
Phase sequence self-checking motor and phase sequence checking method Download PDFInfo
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- CN114167154A CN114167154A CN202111485778.2A CN202111485778A CN114167154A CN 114167154 A CN114167154 A CN 114167154A CN 202111485778 A CN202111485778 A CN 202111485778A CN 114167154 A CN114167154 A CN 114167154A
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- 238000000819 phase cycle Methods 0.000 title claims abstract description 77
- 238000000034 method Methods 0.000 title claims abstract description 28
- 230000006698 induction Effects 0.000 claims abstract description 13
- 239000011810 insulating material Substances 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 5
- 238000007789 sealing Methods 0.000 description 5
- 230000005674 electromagnetic induction Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 238000004590 computer program Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000012795 verification Methods 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/18—Indicating phase sequence; Indicating synchronism
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Abstract
The embodiment of the invention provides a phase sequence self-checking motor and a phase sequence checking method, wherein the phase sequence self-checking motor comprises the following steps: three-phase alternating current motor and terminal box, arranged the phase sequence verifying attachment in the terminal box, the phase sequence verifying attachment includes: the induction ring is electrically connected with the phase sequence checking module, and the phase sequence checking module is electrically connected with the indicating lamp. The invention realizes the self-checking of the three-phase alternating current motor to the phase sequence of the accessed three-phase power supply by combining the junction box provided with the phase sequence checking device and the three-phase alternating current motor, and avoids the safety risk of dangerous operation of the motor caused by the reverse connection of the phase sequences of the power supplies of the motor.
Description
Technical Field
The invention relates to the technical field of three-phase alternating current motors, in particular to a motor with self-checking phase sequence and a phase sequence checking method.
Background
Currently, the judgment of whether the phase sequence connection of the three-phase alternating-current motor is correct can be made by observing the rotation direction of a cooling fan of the motor. However, in the actual use process, due to the limitation of factors such as the installation position of the motor, it is difficult to observe the heat dissipation fan of the motor, so that it is impossible to determine whether the phase sequence of the motor is correctly connected at present. When the motor rotates reversely for a long time, all the operation indexes of the motor do not meet the design requirements, and safety accidents are easily caused.
Disclosure of Invention
The embodiment of the invention aims to provide a phase sequence self-checking motor and a phase sequence checking method, so as to achieve the purposes of self-checking the phase sequence of the motor and alarming for abnormality. The specific technical scheme is as follows:
a phase sequence self-verifying electric motor, the electric motor comprising: three-phase alternating current motor and terminal box, arrange phase sequence verifying attachment in the terminal box, phase sequence verifying attachment includes: the motor wiring terminal is fixed on the insulating bottom plate, the induction ring penetrates through the motor wiring terminal and is fixed on the insulating bottom plate, the phase sequence checking module and the indicating lamp are fixed on the insulating bottom plate, the induction ring is electrically connected with the phase sequence checking module, and the phase sequence checking module is electrically connected with the indicating lamp.
Optionally, the junction box is provided with an observation window, the covering material of the observation window is a transparent insulating material, and the observation window is used for observing the indicator light.
Optionally, the junction box is provided with a wire inlet, and the wire inlet is used for leading in a power line.
Optionally, an elastic sealing ring is arranged in the wire inlet.
Optionally, the outer wall of the wire inlet is provided with threads for installing and fixing a fixing bolt of the power wire.
Optionally, the induction ring is covered with an insulating material.
Optionally, the motor terminal is electrically connected to a lead terminal of the three-phase ac motor.
Optionally, the insulating bottom plate is fixedly connected with the junction box through bolts.
A method of phase sequence checking, the method comprising:
when the control circuit is in an off state, the three-phase power supply is switched on, and three phases of induced currents of the three-phase alternating-current motor are obtained, wherein the three phases of induced currents comprise: an induced current of U phase, an induced current of V phase, and an induced current of W phase.
And respectively generating the phase angle of the U phase, the phase angle of the V phase and the phase angle of the W phase by utilizing a preset phase angle generating algorithm according to the induced currents of the three phases.
Randomly selecting one phase as a reference phase, checking whether the phase angles of the other two phases except the reference phase and the difference value of the phase angles of the reference phase are within a preset threshold range according to preset phase sequence logic, and outputting an instruction of turning on an indicator lamp if the difference value is not within the preset threshold range, wherein the preset phase sequence logic is that the phase angle of the U phase is ahead of the phase angle of the V phase, the phase angle of the V phase is ahead of the phase angle of the W phase, and the phase angle of the W phase is ahead of the phase angle of the U phase.
Optionally, the method further includes:
and when the difference value between the phase angle of the other two phases except the reference phase and the phase angle of the reference phase is in a preset threshold range, not outputting an instruction of turning on an indicator lamp.
According to the phase sequence self-checking motor and the phase sequence checking method provided by the embodiment of the invention, the terminal box with the phase sequence checking device is combined with the three-phase alternating current motor to check the phase sequence of the three-phase power supply, so that compared with the prior art, the phase sequence connection state of the three-phase power supply can be visually displayed, and the safety risk of motor reversal caused by the fact that the problem that the phase sequence is reversely connected cannot be found in time due to the installation position of the motor is avoided. Meanwhile, the invention is based on the electromagnetic induction principle, and carries out phase sequence check in a mode of collecting induced current by the induction ring without much improvement on the existing motor structure, thereby improving the universality of the invention. Therefore, the invention realizes the automatic check of the three-phase alternating current motor on the phase sequence of the power supply and improves the operation safety of the three-phase alternating current motor.
Of course, it is not necessary for any product or method of practicing the invention to achieve all of the above-described advantages at the same time.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a phase sequence self-checking motor according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a phase sequence checking apparatus according to an embodiment of the present invention;
fig. 3 is a schematic cross-sectional view of a phase sequence self-checking motor according to an embodiment of the present invention;
fig. 4 is a flowchart of a phase sequence checking method according to an alternative embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, fig. 2 and fig. 3, for understanding the technical solution of the present invention, a phase sequence self-checking motor, referring to fig. 1, includes: a three-phase ac motor 101 and a junction box 102, a phase sequence checking device being arranged in the junction box 102.
Referring to fig. 2 and 3, the phase sequence checking apparatus includes: motor terminal 201, induction ring 202, phase sequence check module 203, pilot lamp 204 and insulating bottom plate 205. The motor terminal 201 is fixed on the insulating bottom plate 205, the induction ring 202 penetrates through the motor terminal 201 and is fixed on the insulating bottom plate 205, the phase sequence checking module 203 and the indicator lamp 204 are fixed on the insulating bottom plate 205, the induction ring 202 is electrically connected with the phase sequence checking module 203, and the phase sequence checking module 203 is electrically connected with the indicator lamp 204.
Optionally, in an alternative embodiment of the present invention, the motor terminal 201 is connected to a three-phase power line.
Alternatively, in another alternative embodiment of the present invention, when the three-phase ac motor 101 is powered on, the three-phase ac motor 101 is set to be in the idle state in the energized state. The no-load state may be a state in which the motor operates without a load. According to the invention, the no-load state of the three-phase alternating current motor 101 in the power-on state is set, so that the three-phase alternating current motor 101 can not run with load under the condition that the phase sequence verification device does not finish phase sequence verification, and the risk of safety accidents caused by long-time reverse load running of the three-phase alternating current motor 101 under the condition of reverse phase sequence connection is avoided.
Optionally, referring to fig. 1 and fig. 3, the junction box 102 is provided with an observation window 103, a covering material of the observation window 103 is a transparent insulating material, and the observation window 103 is used for observing the indicator light 204.
Optionally, in an alternative embodiment of the present invention, the transparent insulating material may be organic glass. It is understood that, when the above covering material covers the observation window 103, the joint of the above covering material is required to meet the insulation and protection level requirements in the art, and the present invention is not described herein in detail.
Optionally, in another optional embodiment of the present invention, the observation window 103 may be opened on a side wall of the junction box 102, or may be opened on a top of the junction box 102, so as to achieve the purpose of observing the indicator light 204.
Optionally, referring to fig. 1 and fig. 3, the junction box 102 is provided with a wire inlet 104, and the wire inlet 104 is used for introducing a power line.
Optionally, an elastic sealing ring is disposed in the wire inlet 104.
Optionally, in an optional embodiment of the present invention, due to a design requirement for insulation inside the three-phase ac motor, in order to prevent external liquid or impurities from entering the three-phase ac motor through the wire inlet 104 and affecting the operation safety of the three-phase ac motor, an elastic sealing ring is disposed inside the wire inlet 104, and the elastic sealing ring can allow a power line to pass through. Therefore, the integral sealing and insulation grade of the three-phase alternating current motor is improved, and the operation safety and reliability of the three-phase alternating current motor are improved.
Optionally, the outer wall of the wire inlet 104 is provided with threads for installing a fixing bolt for fixing a power line.
Optionally, the inductive loop 202 is covered with an insulating material.
Optionally, in an alternative embodiment of the present invention, the inductive loop 202 may be an induced current detection device based on the principle of electromagnetic induction.
Alternatively, referring to fig. 2 and 3, motor post 201 is electrically connected to lead terminals 301 of three-phase ac motor 101.
Optionally, referring to fig. 2, the insulating bottom plate 205 is fixedly connected to the junction box 102 by bolts.
Corresponding to the above embodiment of the phase sequence self-checking motor, the present invention further provides a phase sequence checking method, as shown in fig. 4, including:
s401, under the condition that the control circuit is disconnected, a three-phase power supply is connected, and induced currents of three phases of the three-phase alternating-current motor are obtained, wherein the induced currents of the three phases comprise: an induced current of U phase, an induced current of V phase, and an induced current of W phase.
Alternatively, in an alternative embodiment of the present invention, the manner of obtaining the induced currents of the three phases of the three-phase ac motor may be based on the principle of electromagnetic induction, and obtaining the induced currents by using an induction loop.
S402, respectively generating a phase angle of a U phase, a phase angle of a V phase and a phase angle of a W phase by utilizing a preset phase angle generating algorithm according to the induced currents of the three phases.
S403, randomly selecting one phase as a reference phase, checking whether the phase angle of the two other phases except the reference phase is within a preset threshold range or not according to a preset phase sequence logic, and outputting an instruction for turning on an indicator lamp if the difference value between the phase angle of the two other phases except the reference phase and the phase angle of the reference phase is not within the preset threshold range, wherein the preset phase sequence logic is that the phase angle of the U phase is ahead of the phase angle of the V phase, the phase angle of the V phase is ahead of the phase angle of the W phase, and the phase angle of the W phase is ahead of the phase angle of the U phase.
Optionally, in an optional embodiment of the present invention, after the operation and maintenance personnel find that the indicator light is turned on, the connection positions of any two power lines of the three-phase power lines connected to the motor terminal are exchanged, so that the phase sequence positive connection of the three-phase power source can be realized. In this embodiment, it is a known technique of a person skilled in the art to replace any two power lines so as to realize the positive connection of the phase sequence of the three-phase power supply, and the present invention is not described in detail herein.
It should be understood that the preset phase sequence logic is a phase sequence required for forward rotation of the three-phase ac motor, and the present invention is not described in detail.
According to the phase sequence self-checking motor and the phase sequence checking method, the phase sequence checking device is arranged in the junction box and combined with the three-phase alternating current motor, so that the phase sequence checking of the three-phase power supply is realized, compared with the prior art, the phase sequence connection state of the three-phase power supply can be visually displayed, and the safety risk of motor reversal caused by the fact that the problem that the phase sequence is reversely connected cannot be found in time due to the installation position of the motor is avoided. Meanwhile, the invention is based on the electromagnetic induction principle, and carries out phase sequence check in a mode of collecting induced current by the induction ring without much improvement on the existing motor structure, thereby improving the universality of the invention. Therefore, the invention realizes the automatic check of the three-phase alternating current motor on the phase sequence of the power supply and improves the operation safety of the three-phase alternating current motor.
Optionally, the method further comprises:
and when the difference value between the phase angle of the other two phases except the reference phase and the phase angle of the reference phase is in a preset threshold range, the instruction of turning on the indicator lamp is not output.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.
All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.
The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.
Claims (10)
1. A phase sequence self-verifying electric motor, comprising: a three-phase alternating current motor and a junction box, a phase sequence checking device is arranged in the junction box,
the phase sequence checking apparatus includes: the motor wiring terminal is fixed on the insulating bottom plate, the induction ring penetrates through the motor wiring terminal and is fixed on the insulating bottom plate, the phase sequence checking module and the indicating lamp are fixed on the insulating bottom plate, the induction ring is electrically connected with the phase sequence checking module, and the phase sequence checking module is electrically connected with the indicating lamp.
2. The motor of claim 1, wherein the junction box is provided with an observation window, a covering material of the observation window is a transparent insulating material, and the observation window is used for observing the indicator light.
3. The motor of claim 1, wherein the junction box is provided with a wire inlet, and the wire inlet is used for leading in a power wire.
4. The motor according to claim 3, wherein an elastic seal ring is built in the wire inlet.
5. The motor of claim 3, wherein the wire inlet outer wall is provided with a thread for mounting a fixing bolt for fixing the power wire.
6. The motor of claim 1, wherein the induction ring is covered with an insulating material.
7. The motor according to claim 1, wherein the motor post is electrically connected to a lead terminal of the three-phase alternating-current motor.
8. The motor of claim 1, wherein the insulating base plate is fixedly connected to the terminal box by bolts.
9. A method of phase sequence checking, the method comprising:
when the control circuit is in an off state, the three-phase power supply is switched on, and three phases of induced currents of the three-phase alternating-current motor are obtained, wherein the three phases of induced currents comprise: an induced current of a U phase, an induced current of a V phase and an induced current of a W phase;
respectively generating a phase angle of the U phase, a phase angle of the V phase and a phase angle of the W phase by utilizing a preset phase angle generating algorithm according to the induced currents of the three phases;
randomly selecting one phase as a reference phase, checking whether the phase angles of the other two phases except the reference phase and the difference value of the phase angles of the reference phase are within a preset threshold range according to preset phase sequence logic, and outputting an instruction of turning on an indicator lamp if the difference value is not within the preset threshold range, wherein the preset phase sequence logic is that the phase angle of the U phase is ahead of the phase angle of the V phase, the phase angle of the V phase is ahead of the phase angle of the W phase, and the phase angle of the W phase is ahead of the phase angle of the U phase.
10. The method of claim 9, further comprising:
and when the difference value between the phase angle of the other two phases except the reference phase and the phase angle of the reference phase is in a preset threshold range, not outputting an instruction of turning on an indicator lamp.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111485778.2A CN114167154A (en) | 2021-12-07 | 2021-12-07 | Phase sequence self-checking motor and phase sequence checking method |
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| CN202111485778.2A CN114167154A (en) | 2021-12-07 | 2021-12-07 | Phase sequence self-checking motor and phase sequence checking method |
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| CN202111485778.2A Pending CN114167154A (en) | 2021-12-07 | 2021-12-07 | Phase sequence self-checking motor and phase sequence checking method |
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| CN111638404A (en) * | 2020-07-03 | 2020-09-08 | 兖州煤业股份有限公司 | Operation phase-failure fault detection display device for coal mine motor |
| CN112083329A (en) * | 2020-08-19 | 2020-12-15 | 中车长春轨道客车股份有限公司 | Debugging system and debugging method for judging rotating direction of traction motor of motor train unit |
| CN214953812U (en) * | 2021-03-31 | 2021-11-30 | 国网浙江绍兴市上虞区供电有限公司 | Non-contact three-phase alternating current phase sequence detection device |
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2021
- 2021-12-07 CN CN202111485778.2A patent/CN114167154A/en active Pending
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| JPH08322283A (en) * | 1995-05-24 | 1996-12-03 | Isuzu Motors Ltd | Inverter controller of permanent magnet type synchronous motor |
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