Lauris Bisenieks

New isolated interface converter for grid-connected PMSG based wind turbines

A new converter topology for a permanent magnet synchronous generator based variable speed wind turbine is presented in this paper. Main focus is on a combined topology of a controlled rectifier and a brand new step-up isolated DC/DC converter. This topology (controlled rectifier coupled with a quasi-Z-source based galvanically isolated step-up DC/DC converter) is essential to generate a regulated DC voltage (400 V DC typical for 230 V AC output) despite wide variations in the output voltage of a wind generator. The operation principles of the proposed topology are given and experimental results are analyzed.

New converter for interfacing PMSG based small-scale wind turbine with residential power network

This paper presents a new converter topology for interfacing a permanent magnet synchronous generator based variable speed wind turbine with a residential power network. The theory of wind energy conversion is analyzed first. Then an example of wind velocity distribution and normalized energy yield is discussed in order to formulate requirements for choosing a power converter. A new topology of an interfacing converter is analyzed and simulation results of a lossless model are presented. Simulation results of the proposed converter prove that its utilization in wind power applications is beneficial.

Development of a Modular Power Converter

Development of a Modular Power Converter This report describes the most important details of elaboration of a versatile power module that can be utilized as a part of various converters. Two or more modules connected together can form a frequency converter or multilevel converter or 3-phase inverter/rectifier etc. Initially the module was developed for fast prototyping of uninterruptible power supplies and energy systems with alternative energy sources. The module can be used also as a basis for laboratory equipment of the power electronics course.

Direct-current supply system with capability of an uninterruptible power supply

The given paper analyzes the possibility of utilization of DC power grid to supply common electrical AC equipment with electrical energy. Features of such system are discussed and compatibility with consumers is analyzed. Benefits of the proposed system for particular consumers are practically investigated. Significant attention is paid to the choice of rectifier for the system in regard to parameters of input and choice of other converters. Various constructions are analyzed and some are investigated by means of simulation. Proposals are made for practical implementation of DC-grid at Riga Technical University.