Frequency conversion speed regulation control technology of paper machine production line

The paper machine is a combined machine composed of a series of ancillary equipment, divided into two parts, the wet part and the dry part. The wet part includes the sizing flow system, wire and pressing parts, and the dry part includes drying, calendering and coiling parts. The production process is generally that the slurry is sent to the front headbox of the paper machine production line through the sizing flow system, and then the slurry flows through the wire section, press, front dryer, post press, post dryer, and calender in turn. The sub-equipment, including the machine and the paper reel, becomes the base paper; the base paper can also enter the off-machine coating and rewinding machine to produce finished paper.

Papermaking is a continuous production process, so the continuous and orderly control of the production line has become a bottleneck restricting the quality and output of finished paper. As the most powerful control method since the mid-1990s, variable frequency speed regulation has entered the papermaking field that originally belonged to the world of DC speed regulation (applicable to large and medium paper machine) and slip motors (applicable to small and medium paper machine), and has achieved good results. Market effect.

AC variable frequency speed regulation technology is recognized as one of the most promising AC speed regulation methods due to its excellent speed regulation performance, significant power saving and wide applicability in the field of national economy. The DC speed control system occupies an important position in the development history of paper machines. However, due to the difficult maintenance and poor environmental resistance of DC motors, the performance-price ratio of the papermaking machine was severely restricted in the 1990s. The frequency conversion speed regulation technology can maximize the inherent advantages of the AC motor (simple structure, sturdy and durable, economical and reliable, good dynamic response, etc.), plus the frequency conversion speed regulation theory has formed a relatively independent subject. The era when the frequency conversion speed regulation technology is fully applied to the paper machine production line has arrived.