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New Tech Tuesdays

Join Rudy Ramos for a weekly look at all things interesting, new, and noteworthy for design engineers.

On a recent trip to South Texas, I was amazed to see how many wind turbines dot the landscape, taking advantage of the prevailing Gulf winds (Figure 1). These huge, three-bladed horizontal-axis wind turbines (HAWT), along with solar, are rapidly becoming considerable renewable energy sources driving substantial change to the traditional power grid. Today, over 72,000 wind turbines across the US generate clean, reliable power, accounting for 151GW of capacity, making it the fourth-largest electricity generation source. This wind power serves the equivalent of 46 million American homes.^[1]

Figure 1: Wind farm of large, three-bladed horizontal-axis wind turbines (HAWT) in South Texas near Raymondville. (Source: Author)

One promising technology that could play a significant role in this shift is the direct current (DC) microgrid. Moving to grids operating on direct current and away from traditional alternating current (AC) grids might hold the key to greater efficiency, reliability, and cost-effectiveness, especially with the push towards decentralized, renewable-powered energy systems.

In this week’s New Tech Tuesday, we explore DC microgrids and their advantages.

Microgrid generally refers to a completely localized energy system more than its size. A key feature of a microgrid is its ability to operate autonomously, either in islanding mode (independent of the main grid) or grid-connected mode. Microgrids typically include renewable energy generation sources, battery storage systems, power electronics, and DC loads—devices and appliances that run on DC power, like laptops, smartphones, and battery storage systems.

In a DC microgrid, all components are optimized for DC power. Systems of varying scales—from small setups of a few kilowatts (kW) for individual homes to larger megawatt (MW) installations for remote communities or extensive facilities—can qualify as microgrids if they integrate the essential elements: power generation, storage, control, and local load management.^[2]

DC microgrids are more efficient than traditional AC grids because they eliminate the need for AC and DC energy conversions while seamlessly integrating renewable energy sources like solar and wind. Battery storage systems designed for DC power provide enhanced energy storage without requiring energy conversion. Additionally, DC microgrids offer localized control over power distribution, making them suitable for remote areas, and can be scaled easily to meet growing energy needs.

One major obstacle when transitioning to DC microgrids is the compatibility of DC systems with the existing AC-powered infrastructure. Most homes and commercial buildings are designed for AC power, requiring careful integration or complete retrofitting to support DC power. Additionally, establishing a DC microgrid may incur considerable upfront costs, especially for specialized power electronics.

This week’s New Tech Tuesday features products from Texas Instruments and Infineon Technologies that can significantly enhance the delivery and efficiency of renewable energy sources.

The Texas Instruments INA740x digital power monitor is a highly accurate current-sensing solution optimized for power delivery, grid infrastructure, and industrial battery pack applications. With an integrated current sensor, 16-bit delta-sigma ADC, and a wide current measurement range, it precisely monitors key parameters like current, voltage, power, and energy, even in high-noise environments. The INA740x’s low offset and gain drift reduce the need for multi-temperature calibration, ensuring reliable performance across variable operating conditions.

Infineon Technologies 2EP1xxR full-bridge transformer driver IC family delivers high-speed switching and robust isolation, which enhances power conversion efficiency and reliability in solar inverters, high-voltage DC-DC converters, and energy storage systems. These ICs feature low propagation delay, high isolation voltage, and thermal efficiency, supporting precise, high-frequency switching. This results in improved power density, reduced system losses, and increased overall reliability, making them well-suited for modern, high-performance renewable energy applications.

While DC microgrids offer energy efficiency and renewable energy integration, obstacles like compatibility with existing infrastructure and upfront costs hinder their widespread adoption. However, as the demand for clean energy grows, DC microgrids may emerge as the preferred solution for a smarter, more efficient energy future.

Sources:

[1] https://cleanpower.org/facts/wind-power/
[2] https://www.energy.gov/eere/wind/how-distributed-wind-works