Design And Networked Control Of Grid-connected Wind And Solar Hybrid Power Generation System

With the situation of energy resource crisis and the problem of circumstance pollution becoming more and more severity, exploitation and utilization of the renewable energy resource is imperative. All countries in the world have seen the development and utilization of new energy as the sustainable energy development strategy in future. Among the available new energies, wind and solar energy have the advantages which are resource-rich, no geographical boundaries and clean, and they also have other unique advantages, so that they have been given more and more attention, but both the stand-alone wind or photovoltaic generation system have their own limitations, therefore, this thesis chooses to design a small-scale wind/solar hybrid generation system as the research object, which is established by making use of the good complementary characteristics of wind and solar energy that both in resource condition and technical application. The research and design of wind/solar hybrid generation system can compensate for the deficiencies of the stand-alone wind or photovoltaic power generation system. According to the complementary characteristics of wind and solar energy, this thesis has studied and designed the wind/solar hybrid generation system, designed the whole generation system controller and realized the grid-connected function. The main work is as follows:Firstly, according to the complementary characteristics of wind and solar energy, the thesis has designed a wind/solar hybrid system controller, analyzed the structure of the control system in detail, designed the hardware circuit and software processes for the controller, compiled the program according to processes, tested the experiment, and at last given the successful measurement results.Secondly, the thesis has achieved energy storage and grid-connected functions of the wind and solar power generation system, analyzed the operation principle and model theory of wind/solar hybrid grid-connected inverter in detail, designed the structural model of inverter and analyzed the main circuit working condition of the inverter. Meantime, the thesis has also designed the filter circuit and islanding detection circuit, established some simulation models about the grid-connected inverter, boost circuit and the islanding detection circuit. In the end, the simulation results and the analysis of models have been given.Finally, the thesis has analyzed the stability of inverter networked control system and the network time-delay problem, analyzed the formation mechanism, composition and the main influence factors about network time-delay in detail, established a closed-loop system mode for the inverter networked control system which exists network time-delay problem, analyzed the influence of time-delay characteristics on the system according to the mathematical model, and studied the generated time-delay factor in the networked control system. For the time-delay and the stability of the power networked system, the thesis takes the compensation measures to guarantee stability of the system.