Last month, when I visited a customer's factory in Jiangsu, the workshop director Lao Zhao pointed to the production line and said with emotion: "This new high-speed packaging machine is nearly twice as fast as our old equipment, but the sealing deviation is two-thirds smaller!" He took me to the observation window and saw chocolate bars rushing on the assembly line. The serrated cuts of each packaging bag were so neat that they looked like they were cut with a ruler. This transformation is the result of the closed-loop control technology of the servo drive system.
As an engineer who has been dealing with packaging machinery for fifteen years, I have witnessed too many cases of "turning over at high speed". In the early years, the industry blindly pursued the speed of high-speed packaging machines, resulting in embarrassing scenes such as heat seal misalignment and material leakage. It was not until our factory implanted closed-loop control technology into the servo drive system that the curse of "speeding up will lead to inaccuracy" was truly broken.
I remember the first day when the new servo drive system was tested, the entire technical department held its breath. When the high-speed packaging machine broke through the critical point of 120 bags per minute, the position error curve on the monitoring screen suddenly changed from a roller coaster to a horizontal line-the fluctuation value of 0.05 mm is equivalent to one-third of the diameter of a hair! The old team leader patted the control cabinet excitedly: "This dual encoder feedback system is more sensitive than a hound's nose!"
The essence of closed-loop control technology lies in "real-time competition". The traditional open-loop system is like a blindfolded race, and the motor only executes instructions; our servo drive system is equipped with an "electronic microscope", which compares the actual position with the target trajectory every millisecond. Last year, when renovating the old line for a Guangdong customer, their technicians found that the high-speed packaging machine equipped with closed-loop control, which is also used to process special-shaped biscuits, has a correction speed more than twenty times faster than manual adjustment.
The changes brought about by this precise control are subversive. Last month, an urgent order from a pet food factory in Qingdao required the square freeze-dried packaging to be replaced with a round can. In the past, it would take most of the day to adjust the gripping mechanism of the high-speed packaging machine. Now, through the online parameter compensation of the servo drive system, the operator can complete the specification switch in ten minutes by swiping a few times on the touch screen. The slogan "Quality is adjusted" on the wall of the workshop can finally be changed to "Quality is controlled".
What makes us most proud is that we have overcome the industry's stubborn disease of "emergency stop jitter". When a high-speed packaging machine brakes in an emergency, the huge inertia often causes the mechanical structure to vibrate. We added a reverse torque compensation module to the servo drive system, just like putting a smart rein on a galloping horse in an instant. Once, there was a sudden power outage at the customer's site. After restarting, the equipment actually automatically completed the unfinished packaging at the moment of power outage, and even the material loss was precisely controlled within the industry's minimum standard.
Now when you walk into the test workshop of our factory, you can see more than 30 high-speed packaging machines "showing off" at the same time: here they are vacuuming 0.3mm thick potato chip bags, and there they are spiral filling 500ml beverage bottles. Although the models are different, the servo drive systems of all equipment follow the same control philosophy - using closed-loop thinking to decompose each action into hundreds of correction nodes. This precise control method made the Swedish customer say "it's like installing the heart of a Swiss watch on the machine" during acceptance.
Watching the new generation of servo drive systems about to be exported to South America, I suddenly remembered that snowy night eight years ago. At that time, in order to verify the effectiveness of the closed-loop control algorithm, our team tested it continuously for eighteen hours in a warehouse at minus ten degrees. Today, those control logics that condense the hard work are on the production lines in more than 40 countries around the world, silently guarding the millimeter-level precision of each high-speed packaging machine.
Perhaps to outsiders, the servo drive system is just a circuit board and gears in a metal shell. But for us, this is the magic box that gives machines "muscle memory" - when the equipment can complete the full closed-loop control of perception, calculation, and execution within 0.1 seconds, the experience that once required the master craftsman to "listen to the sound and identify the position" has truly transformed into replicable industrial wisdom. The next time you pass by the roaring packaging workshop, you might as well listen carefully. In the sound of those regularly running machines, there are many beautiful chords composed by closed-loop control technology.
