크레인 운전패턴에 따른 에너지 효율 분석에 관한 연구

Abstract

Abstract

Container terminals of each country are currently faced with many difficulties such as the increase in marine transportation cost triggered by bigger ship size and changes in distribution environment resulting from specialization, the worsening of the management finance from high oil price and the international environmental regulations according to United Nations Framework Convention on Climate Change (UNFCC). Accordingly, container terminals of each country are now in a desperately need for early response to overcome such difficulties and establish advanced harbor with international competitiveness. As a part of such measure, most of container terminals including Busan Port have introduced and are operating automatic terminal as a part of their various efforts to increase the operational efficiency, and are seeking to improve their productivity through specialization upon establishing complete automation for the trucks within the terminal and partial automation for the trucks from outside by using Automatic Rail Mounted Crane at the yard.

Along with this, they are introducing new mechanisms to improve productivity or actively conducting research and development for port yard equipment to accelerate the process.

Therefore, this study focused on the energy efficiency analysis according to the changes in driving pattern of the automatic cranes being operated at container terminal as one of the plans to assure port competitiveness by establishing environmentally friendly container terminal and reducing energy cost from such perspective.

First of all, as the basic study to improve the energy efficiency of automatic crane, a mathematical modeling was conducted using Lagrange's equation of movement for transfer crane. In addition, it was confirmed that the acceleration value was eco-driving mode in the section of 1∼2.5[m/s²] by conducting the characteristic analysis of the average energy consumption according to acceleration change while changing the value of acceleration in the section of 1∼5[m/s²] based on the induced model.

Next, as the result of analyzing through simulation the efficiency of the energy consumed in three types of fixed driving patterns such as trapezoid type control input, notch type control input and stair type control input determined by the trace of movement of crane, the container terminal that handles 1 million[TEU] annually showed that the eco-driving mode through which the minium of over 850 million won of energy cost could be saved is possible simply by changing the driving pattern.

Along with this, an optimal control method was proposed as the eco-driving method for low-cost, high-energy efficiency driving of crane. In the proposed method, the optimal path is calculated for each section divided upon dividing the path of movement of crane through the same section. Also, it showed that the minimum of over 260 million won of energy cost could be saved through the two methods of the identical partition method that adopts the method of summing the each calculated value and the limited pole point partition method that calculated the optimal path by dividing the movement path curve through limited points.

Therefore, the eco-driving effect was verified through which the total of 1.11 billion won could be saved according to the cost reduction from fixed type driving pattern and optimal control type driving pattern.

It is expected that the eco-driver policy for high-efficiency could be introduced in the future when the energy reduction measure is established according to the waiting time of crane by examining the driving pattern that considers the waiting time and work schedule within the container terminal.