Investigation on energy management strategy of gas-electric marine hybrid propulsion system with improved dynamic programing algorithm

Abstract

An energy management strategy (EMS) is important in marine hybrid propulsion systems while the global optimal solutions are more significant for the EMS to improve the fuel economy of system. Aiming at finding the more accurate global optimal solutions for EMS, an improved dynamic programing (DP) algorithm was proposed to overcome the basic DP algorithms’ weaknesses and improve the fuel economy. Then the model of gas-electric hybrid propulsion system was also established to verify the strategies. What’s more, the improved DP algorithm was applied to the minimum natural gas consumption and charge-sustaining strategy. And a bi-level optimization scheme that decoupled the interaction between the EMS and components matching was also studied. The results showed that the improved DP algorithm not only avoided the shortcomings in the basic DP algorithm such as the weak effect of penalty functions and curse of dimensionality but also gave more accurate solutions. Compared to the basic DP, the improved DP algorithm can reduce the gas fuel consumption by 3.67% and the computational complexity decreases 100 times.