Electronics360: "Power quality challenges integrating renewables into the grid"

It's a good topic. The need to manage EMI and harmonics and the electronic approaches to virtual voltage and frequency management by inverters is interesting, if not in-depth. However, this article suffers from a "traditional" viewpoint of a grid built for large, central and wasteful power generation and long-distance distribution. It overlooks the advantages of distributed generation, the rotational inertia of wind turbines, the benefit of a coming DC super-grid, the smart-grid advances of the past decade, and the growing need for smart DSM.

The only way to eliminate harmonics is to eliminate the power electronics. In a wind turbine, eliminating the inverter would also increase efficiency and reliability and reduce capital and operating cost. Furthermore, the technology required for this improvement would solve the other power quality problems mentioned in the article.

Such a turbine would operate like a central power station, producing pure sine wave power under complete control. The only difference would be that the wind turbine could not control the power level. That depends on the wind, while the operators of a central power station can vary the power input as needed. But this would not cause any problems. The technology that eliminates the inverter allows for continuous operation of the wind turbine regardless of the power input.

These benefits increase faster than the size of the turbine. Since turbine sizes and numbers will only increase, it is of the greatest importance to eliminate the inverters in these machines.

It is not difficult. DeWind has demonstrated it with their D8.2 and D9.2 turbines. But the industry has ignored this technology. Did it think the Voith WinDrive was too expensive? That would be extremely shortsighted, given the enormous long-term benefits of the technique, and there are better ways to do it. Initial cost cannot be a sufficient reason for refusing to use such a method.

Maybe the industry is determined to get back the money it spent on developing inverter technology and will not abandon it regardless of the benefits. There is some justification for this, since the industry is not making much money and must be conservative. But the article makes clear that a crisis is upon it if the industry refuses to get rid of the inverter.

Solar power would require a different means for eliminating the inverter. Maybe the old DC-AC generator would serve. I have nothing worthwhile to say about it for now.