Energy optimization of public service escalators

This paper is to present the results on the new application of variable speed drive using the in-situ data measured by in-fibre fibre Bragg grating (FBG) sensor for energy optimization of an escalator. It also reports the promising potential of this technique for future development of public service escalators. This paper consists of two parts. The first part reviews the existing energy efficient technologies for escalator operation including auto two speed operation, auto on/off operation, and the variable torque operation in which the motor voltage is controlled in order to provide a minimal driving torque when there passenger load on the escalator is light. This operation mode improves the power factor of the motor while maintaining constant speed operation. The second part of the paper presents the proposed new variable speed operation in that the speed of an escalator is adjusted in response to varying escalator loading demand. This operation mode is designed based on the operational characteristics of railway system in which the train´s headway and hence the escalator passenger flow is different at different times of a day.