| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to maintain an underwater current constant by controlling the current between plural electrodes mounted in the underwater part of a ship by the outputs of plural magnetic sensors. SOLUTION: The underwater parts of the ship 1 are provided with the electrodes 2, 3 and a control amplifier 6 calculates and processes the outputs of the magnetic sensors 4, 5. The current (underwater current) to be passed in the water between the electrodes 2 and 3 is controlled in accordance with the result of the calculation and processing. The underwater current to be passed for the purpose of electric corrosion protection, etc., of the hull is controlled by the magnetic sensors 4, 5 which do not require contact surfaces in the sea water. The precision control of the underwater current with a high maintenance property and simple constitution is made possible. In the case a magnetic material exists on the peripheries of the magnetic sensors 4, 5, the output of the magnetic sensor 8 for monitoring the terrestrial magnetic mounted at the front end of a mast 7, etc., of the ship 1 is used and the magnetic material constituting the ship 1 negates the magnetic field generated according to the magnetic bearing of the bow, by which the measurement accuracy of the magnetic field by the underwater current in the magnetic sensors 4, 5 is improved. |
