The electrical energy consumption continues to grow and more applications will be based on electricity in the next decades. We can expect that more 60 % of all energy consumption will be converted and used as electricity. It is a demand that production, distribution and use of electrical energy are done as efficiently as possible. Further, emerging climate changes argues to find future solutions which also are sustainable. Two major technologies will play important roles to solve parts of those future problems. One is the change the electrical power production from conventional, fossil (and short term) based energy sources to renewable energy sources. Another is to use power electronics to achieve high efficiency in power generation, transmission/distribution and utilization. This paper discuss trends of the most promising renewable energy sources, wind energy, which ,integrated with power electronics, is changing the future electrical infrastructure and also contributes steadily to non-carbon based electricity production. The paper’s focus is on the power electronics technologies used in wind turbine systems.