Research On The Detection Technology Of Distributed Generation Grid Connected With Grid

As the cost of non renewable energy consumption continues to increase and the whole society is aware of the importance of protecting the environment. Many countries have begun to develop and promote the development and application of this technology, in order to replace fossil fuels with renewable resources. Relatively small scale distributed power supply system as the main power supply system is an effective complement, played a lot of role.Including the promotion of social environment, economy, energy conservation, the role of the development of green. At present, many researchers are interested in the research of distributed generation and its related technologies.In many ways, the distributed generation technology can be used to make the most efficient use of resources, which greatly reduce the capital investment and the power loss of the power grid. However, even if the main power grid is off, the local load can also be obtained from the distributed power supply power, which greatly increases the reliability of the power grid work and the corresponding security. However, everything has advantages and disadvantages, distributed power generation technology on the one hand to give us a huge return, there are many problems that need to be solved. First of all, the most important problem is how to change the distributed power from the grid work to the island working state.Because of this, it is very important to explore and study the technology of the island detection for the distributed generation and grid connected system.This another way. Firstly, the paper introduces the concept and theory of islanding,followed by an analysis of the principle, analysis, to explore and study the islanding conditions, harm and islanding detection of necessity. It lists the index standard of the Chinese and foreign related island detection and the anti- Island test circuit used in the experiment.By analyzing and studying the principle of many kinds of island detection methods, the blind area of various detection methods are compared. The shortcomings and deficiencies of the current island detection methods are compared and evaluated. At home and abroad are usually active detection and passive detection, there are one kind, two ways to combine the way is conducive to complement their own shortcomings and deficiencies.A kind of improved slip mode frequency shift method by added a process in the algorithm process, while adding a small amount of perturbation, the phase and power gridload phase does not produce equal and opposite to the direction of, and at the same time, on the basis of further limiting the frequency of changes to achieve the results we want is presented in this paper. And Matlab/Simulink simulation results show that this method is feasible and effective.