Optimization strategy of ship energy management system based on differential evolution algorithm

  Objectives  An energy management optimization strategy is proposed which considers the limitation of a ship's power system operation and greenhouse gas(GHG) emissions.

  Methods  This strategy uses the differential evolution algorithm and real number code to optimize the dispatching speed of the ship, start and stop state of the generators and power distribution of the generator set with minimum consumption as the goal. These three plans can ensure compliance with environmental limits while reducing fuel consumption and ensuring efficiency.

  Results  Taking the actual measured data of a cruise ferry as an example, the operating cost of the initial plan(plan 1)is 36 960.5 m.u while the operating costs of plan 2 and plan 3 are 36 938.1 m.u and 35 888.3 m.u respectively, showing a decrease of 0.06% and 2.90% when compared with the initial plan.

  Conclusions  On the precondition that the optimal design method meets the limitations of the ship's generator, diesel engine operation, GHG limit and arrival distance, it can be seen that the ship's speed and propulsion curve become relatively stable, the figure tends to be trapezoidal and the efficiency of the ship's power system and fuel economy are significantly improved, while the amount of greenhouse gas emissions is simultaneously reduced.