Abstract: Due to mutual interference and collision between devices, the speed stability value of the high-voltage inverter of the crane during control is relatively high, not with good control effect. Therefore, the PLC group control technology for high-voltage frequency converters of large tower cranes is proposed. Based on the basic structure and operating principle of high-voltage frequency converters for large tower cranes, the transient current and magnetic flux equations of the frequency converters are obtained, and Laplace transform is applied to obtain the transfer function of the drive system. From the perspective of the overall system, the dynamic response characteristics are considered to avoid mutual interference and collision between equipments. Using the least squares method to identify the operating parameters of the frequency converter, and employing the configuration of the PLC communication program block, we complete the connection of the process data of the frequency converter. We design PLC group control code for frequency converters to achieve collaborative control of multiple frequency converters through cyclic periodic control. The results show that the speed stability value obtained by using the proposed method for group control of frequency converters is lower, and the group control effect is better.

Key words: large tower cranes, high voltage frequency converter, PLC group control, speed stability

摘要： 由于设备之间相互干扰和碰撞,使得起重机高压变频器在控制过程中的转速稳定值较高,控制效果欠佳。为此,文中提出大型塔式起重机高压变频器PLC群控技术。根据大型塔式起重机高压变频器的基本构成与运行原理,求取变频器的暂态电流和磁链方程,并对其进行拉普拉斯变换,求取驱动系统的传递函数,从系统整体的角度考虑其动态响应特性,避免设备之间的相互干扰和碰撞。采用最小二乘法辨识变频器的运行参数,结合PLC通信程序块的配置,完成变频器过程数据的连接。设计变频器PLC群控代码,通过周期循环控制实现多台变频器的协同控制。结果显示,利用所提方法群控变频器得到的转速稳定值较低,群控效果更好。

关键词: 大型塔式起重机, 高压变频器, PLC群控, 转速稳定