基于单电阻的变频压缩机相电流重构方法  

Study on phase current reconstruction of inverter compressor based on single-resistor sampling

作　　者：李岳[1] 徐鸣[1] 黄跃进[1] 顾江萍[1] 沈希[1] 

机构地区：[1]浙江工业大学机械工程学院,浙江杭州310014

出　　处：《机电工程》2013年第4期454-458,共5页Journal of Mechanical & Electrical Engineering

基　　金：国家自然科学基金资助项目(51076143)

摘　　要：为了提高直流变频压缩机的控制效率,降低运行成本,需要对其电动机的定子相电流的精确采样。针对电机三相相电流与直流母线电流及逆变器开关状态的关系,结合压缩机电机的数学模型,采用了一种基于单电阻采样母线电流的电机相电流重构方法。首先,结合永磁同步电机(PMSM)的数学模型,对单电阻电流采样重构三相电流技术及其难点进行了原理上的分析;然后,在空间矢量PWM调制过程中的中、高频调制区的非观测区域采用了预测状态观测器的数学方法,正确、有效地完成了三相电流的重构;最后,基于STM32芯片设计了一套无传感器直流变频压缩机控制的平台。实验结果表明,该方法能够实现正确重构相电流,在低成本的变频冰箱领域具有很高的实际应用价值。In order to improve the control efficiency of the DC inverter compressor and reduce cost, the phase current of motor stator should be sampled. Aiming at the relationship between the motor three-phase current, DC bus current and inverter switch states, three-phase current reconstruction using only a single-resistor in the inverter DC link was proposed. Firstly, based on the mathematical model of permanent magnet synchronous motor（PMSM）, the key technology and difficulties in reconstructing three-phase current by single-resistor sensor were analyzed. Then, a mathematical method of using predictive state observer to the non-observable regions of the middle and high frequency modulation region in the process of space vector PWM modulated was adopted. The three-phase current was constructed effectively and accurately. Finally, based on STM32 chip, a system of senseless DC inverter compressor control was designed. The hardware circuit of the single-resistor sensor was given. The results indicate that this method can correctly reconstruct the phase current and has a high practical value in the field of low-cost frequency conversion refrigerator.

关 键 词：变频压缩机 矢量控制 单电阻测量 相电流重构 永磁同步电机 

分 类 号：TM925[电气工程—电力电子与电力传动] TH45[机械工程—机械制造及自动化]