The Renewal of Electrical Equipments for Paper Industries and Saving Energy

Abstract

The first installation of the sectional drive system of a paper machine by Toshiba was in the year of 1951. And then the DC drive system of thyristor Leonard had been applied to the drive system of the paper machine. And the sectional drive system has been developed dramatically to the fully digital controlled AC drives systems today. The latest system has the great advantage to the conventional systems, but the renewal to the latest system from the existing system have not frequently occurred due to the restriction of the period of shutdown, the initial cost of renewal, and other factors. Actually the existing system automatically have been getting old and old, so the reliability of the equipments have been getting poor and poor.In order to recover the reliability, the drive equipments should be renewed. If the equipments are not renewed. many problems would appear. The spare parts of the equipments may not be manufactured any more, and the number of technicians who can handle the equipments is getting smaller, and the down time of the paper machine may cause the reduction of the production of paper. The predictive maintenance and renewal of the equipments should be usually planed. It is not easy to renew the existing equipments at one time, so the gradual renewal should be considered with paying attention to the hybrid system.This article explains the points to be considered at the renewal of the drive systems for paper industries and the saving energy by applying the medium voltage inverter to fans and pumps with the merit of the inverter.