Research On Electromagnetic Noise Of High Voltage Induction Motor

In recent years,with the improvement of life quality,people pay more and more attention to the environmental problems,and the noise problem is gradually concerned by the society.The motor as an indispensable part of the industry,its operation has a large number of environmental noise pollution,in recent years,the motor design toward the direction of energy efficient and high power density is more prone to the development of high-frequency electromagnetic noise,this type of noise is more harsh and more easily by the human ear feeling,long-term life in such noise,it is easy to make people lower the hearing.Therefore,China promulgated the standard industry to meet the GB 10069.3-2008 standard,The State Environmental Protection Agency also has a standard for environmental noise: sound pressure level shall not exceed 85 dB.That forced the motor manufacturing industry more efforts to research on the noise,The motor noise is mainly composed of electromagnetic noise,mechanical noise and aerodynamic noise superimposed organization,and the study of electromagnetic noise on the motor must be separated from the noise in the superposition of noise,which is used to verify the reliability of the theoretical calculation of electromagnetic noise.In this paper,the research contents include:(1)Electromagnetic noise separation.this research take the following ideas to separate electromagnetic noise from an ontology noise separately:(1)the noise spectrum measurement when the motor is running at no load;(2)the noise spectrum measurement when the motor is running at no load and instantaneous power failure;(3)the noise spectrum measurement when the motor is running at no load and the external fan is removed;(4)the noise spectrum measurement when the motor is running at no load and instantaneous power failure and the external fan is removed;Through the above methods for measuring noise spectrum and then use the addition and subtraction of the sound pressure level can separate electromagnetic noise to research.(2)Electromagnetic noise and the main frequency data acquisition.Combined with asynchronous motor noise specific circumstances,a large number of high-voltage asynchronous motor noise spectrum test data analysis and separation of each typical specifications of the motor model of electromagnetic noise and the corresponding main frequency;(3)Electromagnetic noise analysis software development and reliability verification.According to the theory of acoustic,electromagnetic,vibration and so on,develop a software for analyzing the electromagnetic noise calculation,steady-state harmonic calculation analysis was carried out on the typical specifications of asynchronous motor,The electromagnetic force wave and the stator modal vibration mode are calculated,find out the cause of the motor electromagnetic noise mainly electromagnetic wave order time,frequency and amplitude,and compare to the measurement of electromagnetic noise of the frequency of separation to verification of the reliability of the calculation method;(4)High-voltage asynchronous motor electromagnetic program improvements.In order to reduce the electromagnetic noise of the motor,a series of high-voltage induction motors are improved and the best scheme is calculated.for the improved series motor re-trial Noise spectrum test and the separation of electromagnetic noise and its main frequency,which can be compared to improve the electromagnetic noise before and after the change and further verify the reliability of electromagnetic force wave calculation method.