Research On The Modeling And Control Strategy Of Hybrid Power Energy Management System

The fuel cell energy compared with traditional chemical energy with higher energy conversion rate, use more energy-efficient, does not pollute the environment, and the deficiencies of the dynamic response of shortcomings. A hybrid power system has better performance and higher energy efficiency than a single power supply system in making full use of its features, it is why that been widely researched in the field of energy. Rational energy management system can significantly improve the energy conversion efficiency of dynamic hybrid power system as well as the corresponding system. To address this problem, in this paper the research on the power supply model, hybrid power system structure, operating modes and control strategies, the main contents are carried out as follows:The fuel cells, super capacitors and batteries model is introduced, the operating characteristics are analyzed, resulting in a more intuitive understanding with its output characteristics here, the super capacitor have the output fast dynamic response of high power density, battery can store more energy of high energy density; based on different topology analysis, the DC bus topology is simple, easy to implement; and finalized the hybrid power system, operating mode of each power and the overall topology of the hybrid power system; then established a DC-DC AC small signal mathematical model of the converter, the DC-DC converter operating mode directly controls the operation state of hybrid power system, have a further awareness on the basis of equivalent circuit on the control system of the DC-DC converter.In this paper the works of the proportional- integral- derivative controller is analyzed, and the module of the PID controller based on digital PID control algorithm is set up;further built MATLAB / Simulink simulation model of hybrid power energy management system based on the PID control by using the model of hybrid power and DC-DC converter. Corresponding simulation under simulated load conditions, and the results were analyzed.For the robustness is higher of the energy management system of the hybrid power based on the PID controlled strategy, and the characteristics of the dynamic response is not fast enough, in this paper the control strategy based on rules and the logic threshold and fuzzy logic control strategies are studied.To manage the energy of hybrid power system, set the corresponding control rules on the working mode of the hybrid power systems based on the logic threshold control strategy. Meanwhile, for the control strategy based on fuzzy logic,design the fuzzy controller and fuzzy control rules, then based on the two control strategies module and simulate the complete system on MATLAB/Simulink;further analysis and compare the simulation results.Comparative analysis of these three control strategy simulation results show that there is a higher energy efficiency and better dynamic performance of the energy management control strategy of hybrid power system based on the fuzzy logic.