Research On Control Technology Of Multi-energy Hybrid Isolated Power System Based On Ocean Energy

As the shortage of traditional energy and pollution of environment increasing seriously,renewable energy exploitation has a widely application prospects. Besides many islands arepower shortage or even worse in our country, multi-energy hybrid isolated power systembased on ocean energy can take advantage of the rich ocean energy in island region, whichwill satisfy the power supply request of these populations without electricity. In addition,from the long-term perspective, in prepare for establishing regional power grids, thedevelopment of multi-energy hybrid isolated power system based on ocean energy is veryimportant. And thus ocean energy which will gradually replace traditional energy sourcescan solve the energy crisis and environmental problems in some degree.The system control technology has increasingly higher demand with the developmentof multi-energy hybrid isolated power system based on ocean energy. This paperinvestigates the control technology of multi-energy hybrid power system based on oceanrenewable energy, formulates control strategy for multi-energy hybrid isolated powersystem, and designs the controller which applies in island environment. The main contentsand results of this study are as follows:1. The research progress in domestic and abroad of multi-energy hybrid isolated powersystem based on ocean energy is introduced, and the present research situations of optimalallocation of power supply, hardware circuit of system and the application of software areanalyzed.2. This paper proposes an model based on Genetic Algorithm for optimal allocation ofpower supply on which the characteristics of ocean energy and other renewable energies areconsidered. In this paper, the objective function of economic model is established, and theconstraint conditions are analyzed, which include on-site installation, the hybrid nature ofresources, the matching between power and load. Then the paper takes Daguan Island’sresource and load for example, the optimal allocation of power, energy storage and load canbe drawn by Genetic Algorithm.3. The control strategy of multi-energy hybrid isolated power system based on oceanenergy is analyzed particularly as follows:(1) Three implemental methods of system energy management are analyzed. Thesystem dispatching management is achieved by energy storage system controlling, windpower system and load switching. And the paper gives specific analysis of the systemenergy flow. (2) The paper designs a closed-loop voltage mode for PWM control strategy. In orderto ensure the stability of the Boost converter circuit output voltage in the volatile inputvoltage condition, the PID controller and PWM control are used to build voltage feedbackloop. And the simulation results show the good effect of closed-loop voltage mode forPWM control.(3) Battery group management controlling and charging and discharging algorithms ofconstant voltage and limited current are established, as well as their respectiveimplementation mode. Combined with different system structures, battery groupmanagement storage and simulation are analyzed.4. This paper designs the controller which applies in island environment. The selectionof controller hardware and software equipment carries on according to the system controlstorage and actual conditions. In order to achieve control function and some relatedprotection, the paper has fully considered island environment characteristics to design thehardware, software and anticorrosion of the controller. The study can provide technicalsupport for the design of renewable energy power system controller.