Game-Based Energy Management Method for Hybrid RTG Cranes

Chen Chen,Schofield Schofield,Niu Niu,Gu Gu

doi:10.3390/en12183589

Chen Chen, Schofield Schofield + Show 2 more

Open Access

https://doi.org/10.3390/en12183589

Copy DOI

Abstract

In order to improve the energy efficiency and economic effect of conventional diesel-powered rubber-tired gantry (RTG) cranes in container terminals, various hybrid RTG cranes were studied. However, these current hybrid RTG cranes have several disadvantages, such as high initial investment cost and poor versatility of energy management methods. In this paper, a hybrid RTG crane consisting of a small-sized diesel generator (DG), a ternary material lithium battery, and a supercapacitor (SC) is studied, and a hybrid RTG crane energy management method based on game theory is proposed. The DG, lithium battery, and SC are modeled as three independent agents to participate in the game, and a multi-agent system (MAS) is established. During the RTG crane work process, agents achieve a coordinated and stable working state through the game, i.e., the Nash equilibrium. Three typical crane operation scenarios, the rated load, continuous work, and intermittent work, are simulated and studied. According to the results, combinations of the three devices can meet the power demand and system performance. The power of the DG in the hybrid system is small (only 20 kW), reducing fuel consumption and overall emissions during RTG crane operation.

Highlights

Container ports are important hubs for world commodity trade, where rubber-tired gantry (RTG)cranes undertake container operations in the yard area and are the most common lifting equipment in container ports
When an RTG crane puts down a container, the lift motor acts as a generator, generating regenerated energy
The hybrid RTG crane consisted of a 20-kW diesel generator (DG), a 73.9-kWh lithium battery pack, and a

Summary

Introduction

Container ports are important hubs for world commodity trade, where rubber-tired gantry (RTG)cranes undertake container operations in the yard area and are the most common lifting equipment in container ports. The conventional RTG crane uses a diesel generator (DG) as the sole source of energy; due to the variable load of RTG cranes, the fuel efficiency of DG is low and generates exhaust gas during operation. It goes against the principles of energy conservation and environmental protection. An RTG crane starts and brakes frequently while working, and has a high frequency of mutual conversion between potential energy and electric energy. When an RTG crane puts down a container, the lift motor acts as a generator, generating regenerated energy. The electric RTG cranes can feed this energy back to the grid [2]

Methods

Results

Conclusion