Deep-sea Mining Lifting Hard Tube And The Combination Of Cable Synchronization Decentralized Control System

Lifting pipe system and power supply & information transmission based fiber power combinated cable are two very important parts in the ocean-mining system. The function of pipe is to lift the compound metal-nodules, which are collectted by ocean mining collector from relay station to the ship in the offing. The function of cable is to transmit signal between seabed and offing , simultaneously power can be transmitted. The cable is dropped down synchronously with the pipe, so cable may be stretched and distorted if dropping is too quick.On the contrary, if dropping is too slow, cable may be snapped. So ensuring the synchronous dropping of cable and pipe is very important to safe, reliable, sequential and economic running for mining .The objective of this paper is to study the control problem of pipe-dropping and cable-dropping in the process of ocean-mining. Firstly, process and equipments of pipe-dropping system and cable-dropping system are introduced ,simultaneously the problems in the dropping are analyzed. Then, on the base of analyse on motor characteristic respectively it is started and stopped frequently ,runs slowly and its load changes constantly in dropping of pipe and cable.According to the mathematics model of pipe system and cable system , two closing loops are adopted by two subsystems, namely speed ring , current ring. PI control are adopted in the current loop and fuzzy-PI control are adopted in the speed loop.Finally, the synchronous dropping of pipe and cable can be designed through using parallelled operating control methods based compensator principle. From the result of simulation, we can know that the following-capability and anti-jamming capability in the process of startup and stopping are all improved after speed compensation are jioned in the process of dropping.