As an effort to develop more efficient system for an excavator, EH (Electro-Hydraulic) system has been widely adopted to take the advantage of the well-commercialized EH valves and its control technologies. Utilizing the EH technology, an innovative IMV (Independent Metering Valve) control system for an excavator mechanism, which consists of high capacity EH valve blocks, an electric-controlled pump, and a main controller unit, has been developed by Hyundai Heavy Industries Co., Ltd. This IMV control system can provide tremendous flexibility to the control of cylinder movements and reduce the energy consumption of an excavator.
In this paper, we introduce the major features of the developed IMV control system and propose the novel control algorithm considering optimal power distribution and energy saving. Furthermore, the effectiveness of the proposed system and control algorithm is verified through various experiments conducted on an excavator equipped with the IMV control system. The results are compared with those of conventional machine. It was shown that IMV system could save the energy consumption more than 10% of an excavator.