Squirrel-cage type asynchronous motor energy efficiency online monitoring method based on measurable electrical amount

An asynchronous motor and squirrel-cage technology, which is applied in the field of on-line monitoring of the energy efficiency of squirrel-cage asynchronous motors based on measurable electrical quantities, can solve problems such as the difficulty of directly calculating the operating efficiency and the inability to directly measure the output mechanical power of the motor.

Active Publication Date: 2013-10-09
NORTH CHINA ELECTRIC POWER UNIV (BAODING)
View PDF2 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Aiming at the problem that the output mechanical power of the motor cannot be directly measured in engineering practice, which makes it difficult to directly calculate its

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Squirrel-cage type asynchronous motor energy efficiency online monitoring method based on measurable electrical amount
  • Squirrel-cage type asynchronous motor energy efficiency online monitoring method based on measurable electrical amount
  • Squirrel-cage type asynchronous motor energy efficiency online monitoring method based on measurable electrical amount

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0084] Taking the Y132S-4 and 5.5kW motors with 36 and 32 slots in the stator and rotor as examples, the identification of the speed of the squirrel-cage asynchronous motor will be further explained through the attached drawings. figure 1 It is a schematic diagram of an energy efficiency online identification system for a squirrel-cage asynchronous motor, in which voltage transformers and current transformers are used to collect stator three-phase voltage and current, and the rotor slot can be obtained by performing FFT analysis and torque calculation on the collected electrical quantities Frequency and output torque. During the test, the sampling frequency of each electrical quantity is 10kHz, and the sampling time is 1s.

[0085] figure 2 (a) The stator current waveform diagram shown; figure 2 (b) The stator voltage waveform shown in (b). image 3 It is a 5.5kW squirrel-cage asynchronous motor with a rated voltage of 380V and a 100% load condition. The stator current spe...

Embodiment 2

[0089] Taking Y132S-4 and 5.5kW motors with 36 and 32 stator and rotor slots as examples, the identification of the speed of squirrel-cage asynchronous motors is further explained through the attached drawings.

[0090] Figure 5 It is a 5.5kW squirrel-cage asynchronous motor with a rated voltage of 380V and a load condition of 75%. The stator current spectrum is obtained by fast Fourier analysis of the stator current. From the figure, it can be clearly identified that the rotor slot frequency is 828Hz, and then According to formula (1), the real-time speed of the motor is 1458.75r / min, and the motor speed measured by the actual torque meter is 1459.2r / min. Figure 6 In order to use the air-gap torque method to obtain the motor air-gap torque waveform through the analysis of the motor stator current and voltage data, it can be seen from the figure that the air-gap torque of the motor fluctuates slightly around 26.97Nm. The identified output torque is 26.37Nm, and the actual o...

Embodiment 3

[0094] Taking Y132S-4 and 5.5kW motors with 36 and 32 stator and rotor slots as examples, the identification of the speed of squirrel-cage asynchronous motors is further explained through the attached drawings.

[0095] Figure 7 It is a 5.5kW squirrel-cage asynchronous motor with a rated voltage of 380V and a 50% load condition. The stator current spectrum is obtained by fast Fourier analysis of the stator current. From the figure, it can be clearly identified that the rotor slot frequency is 835Hz, and then According to formula (1), the real-time speed of the motor is 1471.9r / min, and the motor speed measured by the actual torque meter is 1471.4r / min. Figure 8 In order to use the air-gap torque method to obtain the motor air-gap torque waveform through the analysis of the motor stator current and voltage data, it can be seen from the figure that the air-gap torque of the motor fluctuates slightly around 19.3Nm. The identified output torque is 18.75Nm. The actual output to...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a squirrel-cage type asynchronous motor energy efficiency online monitoring method based on measurable electrical amount in the technical field of squirrel-cage type asynchronous motor energy efficiency online monitoring. Firstly, a collected rotor slot harmonic signal in stator current is analyzed and identified so that the rotation speed of a rotor can be obtained; stator voltage and stator winding current at the motor end are collected and analyzed so that output torque of a rotor shaft of a motor can be obtained, output power of the motor can be obtained through the output torque and the rotation speed, and the purpose that motor operation energy efficiency is identified can be achieved. According to the squirrel-cage type asynchronous motor energy efficiency online monitoring method based on the measurable electrical amount, the problem that the output torque and the rotation speed of the rotor shaft of the motor can not be directly measured is solved, operation is simple in field application, the operation energy efficiency of the motor can be rapidly obtained, the method is suitable for common taper slot rotor motors and motors with aliasing of motor rotor slot harmonic magnetomotive force and air gap harmonic magnetomotive force.

Description

technical field [0001] The invention belongs to the technical field of on-line monitoring of energy efficiency of squirrel-cage asynchronous motors, and in particular relates to an on-line monitoring method of energy efficiency of squirrel-cage asynchronous motors based on measurable electrical quantities. Background technique [0002] In the evaluation of motor energy efficiency, the commonly used efficiency test method is the IEEE112B method, which is the motor energy efficiency judgment method recommended in the standard. This method is usually used in the motor energy efficiency judgment or test. The torque speed sensor installed between the motor and the load realizes the accurate measurement of torque and speed, and then obtains the efficiency of the motor. However, the torque sensor is difficult to be directly applied in engineering practice, which makes it difficult to directly measure the output mechanical torque and speed of the motor rotor shaft, which makes it ve...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01L3/26G01R31/34
Inventor 赵海森王庆许国瑞杜中兰刘晓芳
Owner NORTH CHINA ELECTRIC POWER UNIV (BAODING)
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products