Energy-saving thrust distribution method for dynamic positioning based on improved differential evolution mechanism

Abstract

The invention provides a power positioning energy-saving thrust distribution method based on an improved differential evolution mechanism, which comprises the following steps of: step 1, determining adynamic positioning power demand; step 2, establishing a dynamic positioning power distribution mathematical model; step 3, initializing a solution aiming at the power distribution problem in the power positioning; step 4, selecting a mutation mode according to the mutation constant lambda; step 5, performing the mutation operation; step 6, performing the cross operation; step 7, evaluating the adaptive value of all the solutions, and recoding the optimal solution; step 8, judging whether the termination condition is met or not, and if yes, executing the step 9, otherwise, returning to the step 4; Step 9: stopping the loop, outputting the optimal solution, and performing power allocation according to the optimal solution. According to the invention, the thrust required by the power positioning ship is reasonably distributed to each propeller, on the basis of ensuring the safety of the ship, the energy consumption of the ship and the operation cost of the ship are reduced, and the pollution of the ship is also reduced.

Description

technical field [0001] The invention relates to the field of ship automation, in particular to a dynamic positioning energy-saving thrust distribution method based on an improved differential evolution mechanism. Background technique [0002] The main function of a ship's dynamic positioning system (DPS) is to keep the ship in a desired position or to drive the ship along a specified trajectory. It mainly calculates the total thrust and torque required by the ship in real time according to the deviation between the current position state of the ship and the expected value and the external environment interference, and then calculates the propulsion of each thruster equipped by the ship according to the thrust distribution logic method. The required thrust and its angle will be generated, and the control command will be transmitted to the propeller, and the propeller will generate the required thrust according to the command to complete the positioning of the ship. Therefore...

AI Technical Summary

Problems solved by technology

[0005] (1) Limited by the power of the driving machine, the thrust generated by each thruster has a maximum value, and the thruster cannot produce a thrust greater than the maximum value

[0006] (2) The rate of change of the propeller thrust and its angle is limited, and it cannot change greatly in a short time

[0007] (3) The azimuth propeller can rotate 360° around its main shaft, but because of the interaction between adjacent propellers, there is a thrust forbidden zone, so it is necessary to set a range of variation for the rotation angle of each propeller

[0013] At present, the main method of ship dynamic positioning thrust allocation is to ignore the energy consumption characteristics of thrust allocation, and it is difficult to find the optimal solution of thrust allocation.

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