Frequency Conversion Speed Regulation System and Feedback Signal of Straight Wire Drawing Machine
The straight wire drawing machine is a very common type in real life. In the past, it was usually implemented by a DC generator system.
Now with the advancement of its process technology and the widespread popularity of frequency converters, frequency conversion control has begun to be widely used in straight-forward wire drawing machines.
Functions such as drawing variety setting, operation automation, production process control, real-time closed-loop control, and automatic meter counting can be realized through PLC.
The straight wire drawing machine adopts the advanced wire drawing machine technology of the frequency conversion speed control system, which saves significant energy. The speed regulation range is 30:1 during normal operation, and it can provide more than 1.5 times the rated torque at 5% of the rated speed. , the system logic control of the straight-forward wire drawing machine is relatively complex, with various linkage relationships, and is implemented by PLC.
Synchronization control is all implemented inside the Inovance MD320 inverter and does not rely on external control.
During the working process, the straight wire drawing machine will effectively determine the speed of the operation according to the operator’s panel setting. The analog signal of the speed enters the PLC, and the PLC outputs the analog signal according to a certain slope after considering the acceleration and deceleration time.
The purpose of this is mainly to meet the needs of some operations such as inching and threading.
The analog voltage signal output by the PLC is simultaneously connected to the AI2 (AI1 can also be used) input terminals of all frequency converters as the main speed-given signal.
The signal of each swing arm displacement sensor is connected to the corresponding drum drive inverter as a feedback signal for PID control.
According to the position of the swing arm in the middle, set a given value of PID yourself. This system is a very typical PID control system with feedforward, one level in series, and one level in series, with PID as the fine-tuning amount.
There are six drums with a diameter of 400mm in the drawing part. A cylinder swing arm is installed between each drum to detect the position. A displacement sensor can be used to detect the position of the swing arm. When the wire is pulled tight, the wire will generate pressure on the cylinder of the swing arm, causing the swing arm to move downward.
The last part is the winding motor. This part uses a self-sliding tapered bracket. The winding diameter does not change during the whole process, so there is no need to use the winding diameter calculation function.
The power of eight motors adopts special frequency conversion motors and are equipped with mechanical braking devices.
