Power electronics converters without DC energy storage in the future electrical power network

Power electronics is an integral part of modern energy systems. Moreover, its use adds costs to capital investments in energy systems, along with some reliability issues. Therefore, innovative solutions in power networks require power electronics topologies that are less expensive and more dependable. The use of power electronics without DC energy storage elements (all-silicon solution) is one way to address these issues. This paper provides a comprehensive review of past and present converter topologies without DC energy storage elements which can be employed in novel energy systems. In this paper the converters are divided into two groups: with constant output frequency, and with variable output frequency. The first group includes topologies of matrix and matrix-reactance choppers and their applications in hybrid transformers and power electronic transformers. The second group includes frequency converters based on the matrix converter, covering the conventional, indirect, sparse matrix converter and the matrix-reactance frequency converter. The second part of the article concerns the application of the mentioned converters in the power system functioning as a power interface with AC distributed sources and systems for improving energy quality and the control of power flow in the power network. The sections in this part of the paper present an operational description, and simulation and experimental test results of selected converters and their applications. In the last part of the article there is a brief discussion of current trends, challenges and areas of potential applications and limitations.