基于PLC控制的双变频双电机励磁控制研究

Based on PLC control of double frequency double motor excitation control research

以提升传统双变频双电机的励磁控制精度为目的,提出基于PLC控制的双变频双电机励磁控制方法。构建双变频双电机数学模型,在该模型下安装PLC控制器,并确定控制器的输入项与运行程序。采集双变频双电机励磁信号,在此基础上检测设备的频率和相角,并测量电机转速。最后利用PLC控制器,通过控制量校正、形成触发脉冲、励磁电压、频率与无功功率控制等步骤,实现双变频双电机的励磁控制。实验结果表明:设计方法的平均控制误差低于1%,且平均超调量低于5%,即具有较高的励磁控制精度。

In order to improve the excitation control accuracy of traditional dual frequency conversion and dual motor,a dual frequency conversion and dual motor excitation control method based on PLC control is proposed.The mathematical model of double frequency conversion and double motor is constructed.The PLC controller is installed under the model,and the input items and operation program of the controller are determined.The excitation signals of dual frequency conversion and dual motor are collected,and then the frequency and phase angle of the equipment are detected,and the motor speed is measured.Finally,the excitation control of dual frequency conversion and dual motor is realized by using PLC controller through the steps of control quantity correction,formation of trigger pulse,excitation voltage,frequency and reactive power control.The experimental results show that: the average control error of the design method is less than 1%,and the average overshoot is less than 5%,which means it has high excitation control accuracy.