May 2022 / Vol. 27 No. 5

By Bahar Anvari, Senior Electromagnetic Engineer, Infinitum Electric

In 2021, Winter Storm Uri, what Texans refer to as “Snowmageddon,” left more than 3.5 million residents without power for multiple days. Many residents relied on alternative fuel sources for cooking, heating, and powering their household appliances and communications devices.

According to the National Oceanic and Atmospheric Administration, extreme weather events have increased by more than 4 percent over the past four decades, with high-impact disasters increasing significantly since 2007. With the rise of severe weather and natural disasters, it should come as no surprise that home generators are in high demand. 

A Propane Education and Research Council study found that 23 percent of respondents purchased a generator in the past two years, and 54 percent considered one. New research suggests that the global generator sales market will reach 28.6 billion USD by 2027, up from an estimated 21.6 billion in 2022.

While generators have become more energy-efficient over time, requiring less and less fuel, there is still work to do for this growing product segment for homes and businesses. NEMA’s “Beyond Efficiency” initiative challenges members to develop innovative products for increased energy savings and reliability. Manufacturers of newer, more innovative power generators must also think beyond component efficiency and take a systems-level view for even greater sustainability and reliability. This may involve sustainable manufacturing practices, products that reduce energy demand and emissions across the system’s life, and ways to incorporate end-of-life recyclability.

At Infinitum Electric, we have always strived to design electric motors that go beyond efficiency, with sustainability and reliability being a top priority. For example, our alternators developed for power generation purposes are one-third the size and weight of a traditional alternator yet produce the same amount of power with high reliability and lower operating costs over the system’s life.

Below are five considerations for designing products that go “beyond efficiency” based on our experience designing next-generation alternators:

Lighten the Load

Consider developing products with lighter materials. Most generators are large and heavy for job sites in construction and on oil fields, making them difficult and costly to haul. We replaced bulky, heavy copper materials with a smaller, lighter-weight printed circuit board to design a better alternator. This lightweight material can generate the same amount of power as traditional alternators in a significantly smaller and lighter package than conventional alternators. As a result, transportation of portable generators is more sustainable, and the installation of permanent generators is greatly simplified. Furthermore, a traditional stator features a laminated steel core with copper windings, and up to a third of the motor, losses are caused by eddy currents in that steel core. When the core and copper windings are replaced by copper traces etched into a PCB, the core losses are eliminated, which provides a higher efficiency motor.

Make it Modular

Evaluate options to leverage modular architecture. With a modular design, engineers can gain the flexibility to build multi-stator, multi-rotor alternators to best meet power generation needs. Modularity offers the ability to assemble products on-site, speed delivery time, reduce shipping and logistics costs and the associated emissions. Segmented parts also allow users to easily replace components when they fail and recycle parts that are removed, rather than throwing them in a landfill.

Double Down on Durability

Examine options for materials and designs that increase durability. We removed the need for a complex exciter by using permanent magnets — improving reliability through a simplified design while achieving better performance. On top of that, etching copper onto the printed circuit board improves long-term durability because the coils are perfectly symmetrical and fully insulated, eliminating thermal-induced stress and increasing the reliability over the product’s life.

Simplify the Supply Chain

Determine which materials can be easily produced to eliminate supply chain dependencies. For example, any local contract printed circuit board (PCB) manufacturer can make our alternators on common PCB fabrication equipment. PCBs can be built in several regions globally and allow for production closer to where products are consumed, also reducing lead times, shipping and logistics costs, and associated emissions. Simplified supply chains improve the reliability and resilience of products.

Step up the Control

Evaluate new methods and technologies that improve power control. Our alternators use permanent magnets for field excitation, eliminating the field coils, brushless exciter, and automatic voltage regulator (AVR). They’re also tied to the grid through an efficient AC/AC converter that provides fast and precise voltage and reactive power regulation in a smaller and lighter package. Improved power controls reduce wasted electricity and improve overall system efficiency. The motor is also controlled with an integrated drive, a standard six-pulse drive topology using highly efficient Silicon Carbide (SiC) MOSFET switching devices, which enable higher switching frequency and more robust motor control.

The next generation deserves products that go beyond efficiency, and designing products that incorporate reliability and sustainability will require some rethinking. These five considerations can help us all think through the parameters that matter most as we strive to design and deploy better products for the planet over the system’s life. ei