New Topologies of PCS Applied to Large-scale Battery Energy Storage System

After large-scale wind power and photovoltaic power is connected with the grid, the inherent intermittent and volatility of wind power and photovoltaic power adversely affects the security and stability of the grid. So, researches on the appropriate technology of large-scale battery energy storage system are very important. Power Conversion System (PCS) is an important component of the battery energy storage system. The article respectively makes a comparative analysis of the two parts of PCS-the converter and the filter. Combined with existing battery technology, articles that compared with traditional converter which contains the DC / DC link and DC / AC link, the converter which only contains a DC / AC link and the converter that contains the Z-source network and DC / AC link, have a higher energy conversion efficiency, and they are easy to control; compared with the traditional L filter and LC filter, the LCL filter can suppress high harmonics better, reduce the inductance value effectively, improve the dynamic performance of the system, and be less affected by the grid. Combined with analysis conclusion, the article concludes with two new PCS topologies.