굴삭기 전기동력시스템의 동작점 제어 알고리즘에 관한 연구

Abstract

This paper presents an optimal operation point control algorithm for a hydraulic pump and an electric motor in an electric excavator system. The system consists of a hydraulic pump and a motor: the one delivers the power to hydraulic actuators and the other conveys the power to the hydraulic pump. The system requires an operating point control with efficiency maps of the motor and the hydraulic pump respectively because the efficiency feature of the system is different from that of conventional diesel engine excavator. In this paper, an integrated efficiency map is derived from each efficiency map of the motor and the hydraulic pump. Operation points are produced where the integrated efficiency is the maximum under the same power and the same pressure condition. An optimal operating point control algorithm of the electric-hydraulic system is proposed and simulations are performed through the MILS (Model-In-the-Loop Simulator). The efficiency of this system is improved compared with that of the uncontrolled electric-hydraulic system.