Research On Control Strategy For PV System With DC Bus

In order to deal with energy crisis and environment problem which is becoming more and more serious in 21st century, countries in the world work hard to take advantage of the renewable energy, for example, solar energy. PV power system which includes stand-alone pv system and grid-connected pv system is the important form of making use of solar energy. PV power system with DC BUS is a novel mode of photovoltaic power system. It can not only form stand-alone pv system with DC BUS to solve power problem of remote areas, and it can also be connected to grid with network interface to form grid-connected pv system with DC BUS, which provides an important network model for building integrated photovoltaic. The control strategy of system is directly related to system stability and efficiency of utilizing solar energy, therefore, it is carefully researched in the paper.On the basis of reading many related foreign and national literature, the output characteristics of solar cells are introduced, and the engineering mathematical model is established. In order to utilize output power of solar cells effectively, it is necessary to adopt maximum power point tracking (MPPT) which is actualized by adopting Perturb&Observe Algorithms (P&O) method. The paper does some research on the whole day output rule of solar cells based on P&O method. the paper introduces the principle of battery and bi-direction converter whose roles in system is analyzed.Based on depth research on the main circuit of stand-alone pv system with DC BUS, the control principle and control strategy are proposed. The simulation results based prove the feasible and reasonable of the control strategy. The paper proposes the preliminary solution in order to dispose the problem in system.In order to solve the deficiencies of stand-alone pv system with DC BUS, the paper proposes a control strategy based on the analysis of the main circuit of grid-conncted pv system with DC BUS. To prove the control strategy is appropriate, simulation is done.The experimental platform of pv system with DC BUS is built up. In order to prove the theoretical analysis is correct, experiments are done on the platform.