关键词: 空气压缩机, 全转速范围, 电磁力, 电机转速, 变频器

Abstract: Due to the nonlinear magnetic circuit characteristics of the air compressor, it is difficult to control the electromagnetic force within the full speed range, resulting in excessive vibration and noise during the operation of the air compressor, which affects the control range of the electromagnetic force. A current-electromagnetic force automatic control method for the full speed range of the air compressor was proposed. Based on the motor mechanism of the air compressor, the electromagnetic force magnetic circuit characteristics were analyzed, and a two-dimensional finite element model of electromagnetic force was established to obtain the nonlinear relationship between electromagnetic force and current, and
thus determine the control strategy. Further analyze the skeleton rotation speed during the acceleration, deceleration, and uniform speed stages of the electric motor to obtain the relationship between the motor speed and the power frequency. The adjust it through a frequency converter, and control the duty cycle inside the air compressor by adjusting the switching state and current of the solenoid valve, thereby adjusting the magnitude and direction of the magnetic force. Determine control decisions by setting objective functions and transmit them to solenoid valves and frequency converters to coordinate the regulation of electromagnetic force. Thus achieving automatic control of electromagnetic force across the entire speed range of the air compressor. The experimental results show that the maximum control value of this method for electromagnetic
force is 112 N.

Key words: air compressor,full speed range,electromagnetic force,motor speed,frequency converters