How Businesses Can Use 3D Printing

3D printing is a form of technology that is taking the world by storm. Although the concept has been around since the 1980’s, it’s only in the past few years that it’s become a legitimate means of manufacturing and prototyping. In fact, major companies like Ford, General Electric and Mattel have already implemented this technology. As […]

Anatomy of a Grid Tie Inverter

This post is first in a series discussing the subsystems and key components that go into a grid-tie inverter (GTI), and design considerations for the development of a practical commercial system. The majority of topics will apply equally to active front-ends (AFEs), and active rectifiers (more on the subtle differences between these two is covered […]

Common Mode Filtering Considerations for Grid-Tie Inverters

In non-isolated, grid-tie inverter applications, it is common practice to connect the neutral point of the 3-phase AC grid to earth ground. Unfortunately, this creates a problem for DC link common mode filtering. Typical control methods utilize space vector modulation to control the power stage, which introduces a common-mode voltage in order to maximize the […]

Grid Energy Storage Is a Growth Industry to Watch

The market for grid energy storage is robust and growing. According to a study published by GTM Research, the U.S. market for utility-scale grid storage is expected to rise from an annual value of about a quarter of a billion dollars in 2009 to about $2.5 billion by 2015. The potential exists for continued rapid growth […]

Wind Power Projection Dependent on Improved Energy Storage Technology

Long believed by many to be one of the “purer” sources of alternative energy, and wind power projection has noted the rapid growth in the industry during recent years.  The World Wind Energy Association calculates that electricity from wind accounted for 2.5% of worldwide consumption in 2010 at 430 TWh, and that this output doubled […]

Utility-Scale Flywheel Energy Storage & Grid-Tie Inverters

A few days ago Beacon Power announced that their installation of the world’s first 20MW Flywheel plant is currently operating at 18MW, and is expected to be running at its full, 20MW capacity before the end of the month.  We’re pretty excited about this at Oztek, as we provide the controls for both the grid-tie inverter that interfaces […]

Power Factor and Grid-Tie Inverters

One reason engineers specify active rectifiers (a.k.a. active front-ends) for their systems is that they can operate with near unity power factor.  Being nearly the same system (see my recent post “Active Front-end or Grid Tie Inverter?“), grid tie inverters share this same beneficial characteristic.  However, this does not mean that an active rectifier or […]

Active Front-end or Grid-tie Inverter?

We have the habit here at Oztek of using the term “active front-end” (AFE) and grid-tie inverter (GTI) interchangeably.  On more than one occasion discussing our grid-tie inverter controller, I’ve caught myself somewhere mid-conversation inadvertently switching to using the term active front-end.  It’s of no concern internally, but quite frequently it’s cause for confusion when speaking […]