THRUST CONTROLLER FOR PROPULSION SYSTEMS WITH COMMONLY DRIVEN, CONTROLLABLE PITCH PROPELLERS

摘要

A method and apparatus for controlling the thrust delivered by each propeller of a marine propulsion system of the type having a plurality of controllable pitch propellers driven by a common power source. In response to electrical signals supplied to define commanded thrust levels for the propellers, the power source is controlled to provide the power necessary to satisfy the power requirements of the propulsion system and the propeller pitches are individually set so that each propeller absorbs only its proportionate share of the power. Alternative provision is made for carrying out the foregoing in a speed mode or in a power mode. In the speed mode, the power source is controlled in response to any given set of commanded thrust levels so as to maintain the propellers rotating at a substantially constant speed which is selected to be the higher of a predetermined idle speed for the propulsion system and of the minimum speed necessary to satisfy the highest of the commanded thrust levels. In the power mode, the power source is controlled in response to any given set of commanded thrust levels so as to deliver a substantially constant amount of power which is selected to be the power necessary for the propellers to deliver the amounts of thrust commanded therefrom without their shaft speed dropping below the idle speed. The method and apparatus are also compatible with an operation of the propulsion system in which separate engines are dedicated to the several propellers.