Power Electronic Converters in DC Microgrid

Some specialists claim that present power systems come to the end. The first of all reason is fossil fuels run low. One of the solutions allows avoiding the problem is local balancing of power production and power demand. The easiest to reach local non fossil carriers are wind, sun and water and biomass energy. But they are unstable and it is very hard to produce stable power from them. Microglia´s were developed to solve the problem. The microgrid is small power system composed of power plants, controlled and uncontrolled loads and control system (just like in classic, huge power system). Because microgrid is rather small it has to be an automatic and operate without any staff. Hence, many electronic devices are necessary. First of all these are power plants controllers. The plants using in the microgrid are electronic devices. Also some loads are connected through electronic connection units. Power electronic converters are the most important part of both plants and connections. The paper discusses some problems of power electronic converters in author´s DC microgrid. The converters are divided into groups depending of their destination. The main groups are presented in more details.