Microgrids can be defined as small distributed system that can operate both connected or disconnected from the main grid. Thanks to this property, users that are connected to microgrids can obtain a high quality energy supply. Moreover, a cleaner and more reliable electric generation can be achieved if ecological and economic aspects are considered. However, the presence of microgrids is still limited due to, among other factors, the absence of standards for these kind of systems. At the beginning of this thesis, a summary of the main aspects of the distributed generation will be presented. In this manner, the most typical power converters used on distributed generation, control basics and the main modulation and commutation techniques will be presented. Then, fundamentals of the electrical microgrids will be described such as protections, topologies and control systems. This last issue is especially interesting since a microgrid involves a great amount of tasks that can be dealt in different manners. In this sense, the most common control will be described, the hierarchical control, analyzing its two operation modes: centralized and decentralized. Among the different control loops involved, the droop control, located at the first level of the control, can be highlighted. This control guarantees the basic operation of the microgrid, taking care of the load sharing and frequency and voltage regulation. New solutions for the control of microgrids will be reported. In this sense, a new design of the droop control will be provided that ensures a good stability of a microgrid in its whole range of load. In the same manner, a linear model that considers both electrical and control schemes of a microgrid will be detailed. This model is the basis of the design of the droop control and can be adapted to different microgrid features. Thanks to this design, a good performance of the microgrid is ensured that is validated by means of experimental tests. Finally, this thesis will provide new solutions for the secondary control of microgrids. This control level comprehends two main tasks: voltage and frequency restoration and synchronization with the main grid. An innovative restoration control that considers the different dynamics of the DGs will be provided. Moreover, this control will be properly designed in order to ensure a voltage and frequency restoration while maintaining a good power quality on the microgrid. Furthermore, this control will be based on low-bandwidth communications that provide an economical and reliable solution. This thesis will consider the two operation modes of the microgrid presenting a new synchronization algorithm. This algorithm will be also based on the same low-bandwidth communications used for the restoration control. This algorithm will guarantee a fast and smooth synchronization in order to ensure a good connection with the main grid.