January 17, 2023 Volume 19 Issue 02

Electrical/Electronic News & Products

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Fluke 831 Laser Shaft Alignment Tool

Misalignment causes at least half of all damage to rotating machinery, but instead of fixing the problem, teams often just treat the symptoms by replacing bearings, couplings, and seals. The new Fluke 831 Laser Shaft Alignment Tool makes shaft alignment easy with an intuitive guided user interface that enables quick and complete shaft alignment without advanced training or complicated programs.
Learn more.


Image sensor for virtual reality, drones, machine vision

OMNIVISION has just announced the OG0VE global shutter (GS) image sensor, a small-form-factor, high-sensitivity device for AR/VR/MR, metaverse, drone, machine vision, and barcode scanner products. This new-generation image sensor is 26% smaller and more than 50% more power efficient than its predecessor. It supports one-lane MIPI D-PHY at up to 800 Mbps and was designed to address the high market demand for the smallest and lowest power-consuming cameras.
Learn more.


Smallest Smart Motor Module for DC fan applications

Alpha and Omega Semiconductor Limited has introduced an extension to its compact Smart Motor Module (SMM) family. Available in an ultra-compact, thermally enhanced 3-mm x 3-mm QFN-18L package, the highly integrated AOZ9530QV SMM is a half-bridge power stage with a slew of features and protections that simplify motor drive designs. It is suitable for use in a large number of BLDC fan applications ranging from PC and server fans to seat cooling and home appliances.
Learn more.


Application Note: Wireless -- Decoupling high-frequency signals from a DC supply

From 5G systems to radio and antenna applications, wireless communication accompanies us throughout our daily lives, so the demand for universal high-frequency amplifiers is correspondingly high. By selecting the optimal passive components, the transmission characteristics of the amplifier can be improved during development. A well-designed layout further improves RF performance. The aim is to transmit both RF signals and the DC supply on a single line without interference or cross-talk. A key component is the inductor for decoupling the RF and DC supplies.
Read this in-depth W├╝rth Elektronik application note.


Smallest all-in-one LIN driver propels relay window lifters

Melexis' new LIN pre-driver IC for relay DC motors offers a combination of high power, compactness, and attractive pricing. The MLX81160 is the latest addition to the company's Gen3 family of compatible embedded motor drivers. Its 48-KB of memory (16 KB ROM for the included LIN protocol and 32 KB Flash for the application software) is suitable for applications like window regulators.
Learn more.


Pull-type solenoids in a range to meet tons of applications

Magnetic Sensor Systems (MSS) has released their S-20-100X model of high-efficiency, low-cost Pull Type Tubular Solenoids (1 in. diameter x 2 in. long). Their S-20-100X series features 18 different solenoids to select from based on the voltage, duty cycle, force, and stroke requirement of the user. MSS solenoid coils typically use Class F 23- to 40-AWG windings with Class A insulation for better protection of the solenoid during longer duty cycles. Applications include: vending machines, medical dispensing, mixing, valve control, farm machinery, disconnects, transmission shifting, fire suppression systems, cabinet locks, door controls, and sorting equipment.
Learn more.


Industrial imaging at warp speed

When fast-moving scenes need to be captured in all their details, a high-performance transmission interface is essential in addition to the right sensor. With uEye Warp10, IDS Imaging Development Systems GmbH is launching a new camera family that, thanks to 10GigE, transmits data in the Gigabit Ethernet-based network at a very high frame rate and virtually without delay. The first models with the IMX250 (5 MP), IMX253 (12 MP), and IMX255 (8.9 MP) sensors from the Sony Pregius series are now available.
Learn more.


Top Tech Tips: How to specify electric rod-style actuators for optimal performance, reliability, and efficiency

Andy Zaske, Vice President, Tolomatic, provides his Top 10 Tips for specifying electric rod-style actuators, which have a higher initial cost, more advanced design, and more predictable performance compared to fluid power cylinders. This is a really thorough presentation filled with useful information.
Read the full article.


Standard IP65 slip rings with short lead times

The Orbex Group, a leading manufacturer of high-performance electric motors and slip rings, introduces standard slip rings with an IP65 protection rating, providing washdown tolerance in many food, beverage, and pharmaceutical manufacturing applications. These washdown-ready slip rings feature stainless steel or aluminum housings. They offer flexible mounting options with through-hole diameters ranging from 25 to 100 mm, or capsule style when a through-hole is not required.
Learn more.


New polymers engineered for e-motor applications

Freudenberg Sealing Technologies has expanded the use of its Thermally Conductive, Electrically Insulating (TCEI) materials to produce walled slot liners for electric motor applications. The company's TCEI material grades demonstrate superior thermal conductivity and better electrical insulation when tested against other thermoplastic materials currently available.
Read the full article.


Heatsink solutions for electronic housings

Phoenix Contact has increased the breadth and depth of its popular Industrial Case System (ICS) housing family to include both customizable passive heatsinks and heatsink fillers. New heatsink solutions allow design engineers to choose from a wide range of thermal management solutions to keep their components from overheating. To support the new heatsink solutions, a web-based, intuitive platform for thermal assessment has been incorporated into the Electronic Housing Online Configurator tool on Phoenix Contact's website.
Learn more.


Mini-FAKRA cable assemblies for automotive and industrial applications requiring high data transfer rates

Amphenol RF has expanded its AUTOMATE Type A Mini-FAKRA product series with pre-configured cable assemblies. These assemblies feature a straight quad port mini-FAKRA jack on both ends and are designed on low-loss TFC-302LL. AUTOMATE assemblies support data transmission rates up to 20 Gbps, which makes them ideal for automotive and industrial applications that require high data transfer rates to communicate information for safety, performance, and entertainment without lag.
Learn more.


New compact touchless linear position sensors

The TFD Series of touchless linear position sensors from Novotechnik provides wear-free operation in tight spaces. The TFD-4000 Series uses a magnetic position marker to provide a touchless measurement range of 0 to 14, 24, or 50 mm -- depending on model. These sensors make measurements through air and non-magnetic materials. Sensing direction can be either parallel or perpendicular to mounting holes. Applications include textile, packaging, and sheet metal machinery; medical applications; marine; mobile engine management; and construction, agricultural, and forestry machinery.
Learn more.


Top Tech Tip:
2D, 3D, or 2.5D? Choosing a vision system for your automation project

If you're looking at machine vision systems for automation, you will need to decide whether to invest in a 2D, 3D, or 2.5D camera system. That choice will have a major impact on the deployment's cost, complexity, capabilities, and functionality. OnRobot's Kristian Hulgard, General Manager - Americas, explains the differences, benefits, and shortcomings of each system type.
Read this informative OnRobot article.


Next-generation electronic digital comparators

The Millimess 2000 W(i) and 2001 W(i) Digital Comparators from Mahr set new standards in metrology with unique and innovative features such as touch display, inductive measurement system, and integrated wireless connectivity. The systems combine practical and reliable operation with maximum precision using a unique inductive measuring system.
Learn more.


Heat engine cell with no moving parts is as efficient as a steam turbine

A thermophotovoltaic (TPV) cell (size 1 cm x 1 cm) mounted on a heat sink designed to measure the TPV cell efficiency. To measure the efficiency, the cell is exposed to an emitter, and simultaneous measurements of electric power and heat flow through the device are taken. [Credit: Photo by Felice Frankel]

 

 

 

 

By Jennifer Chu, MIT

Engineers at MIT and the National Renewable Energy Laboratory (NREL) have designed a heat engine with no moving parts. Their new demonstrations show that it converts heat to electricity with over 40% efficiency -- a performance better than that of the average turbine-based heat engine system efficiency in the United States.

The heat engine is a thermophotovoltaic (TPV) cell, similar to a solar panel's photovoltaic cells, that passively captures high-energy photons from a white-hot heat source and converts them into electricity. The team's design can generate electricity from a heat source of between 1,900 to 2,400 C, or up to about 4,300 F.

The researchers plan to incorporate the TPV cell into a grid-scale thermal battery. The system would absorb excess energy from renewable sources such as the sun and store that energy in heavily insulated banks of hot graphite. When the energy is needed, such as on overcast days, TPV cells would convert the heat into electricity, and dispatch the energy to a power grid.

With the new TPV cell, the team has now successfully demonstrated the main parts of the system in separate, small-scale experiments. They are working to integrate the parts to demonstrate a fully operational system. From there, they hope to scale up the system to replace fossil-fuel-driven power plants and enable a fully decarbonized power grid, supplied entirely by renewable energy.

"Thermophotovoltaic cells were the last key step toward demonstrating that thermal batteries are a viable concept," says Asegun Henry, the Robert N. Noyce Career Development Professor in MIT's Department of Mechanical Engineering. "This is an absolutely critical step on the path to proliferate renewable energy and get to a fully decarbonized grid."

Henry and his collaborators published their results April 13 in the journal Nature.

Jumping the gap
More than 90% of the world's electricity comes from sources of heat such as coal, natural gas, nuclear energy, and concentrated solar energy. For a century, steam turbines have been the industrial standard for converting such heat sources into electricity.

On average, steam turbine systems reliably convert about 35% of a heat source into electricity, with about 60% representing the highest efficiency of any heat engine to date. But the machinery depends on moving parts that are temperature limited. Heat sources higher than 2,000 C, such as Henry's proposed thermal battery system, would be too hot for turbines.

In recent years, scientists have looked into solid-state alternatives -- heat engines with no moving parts that could potentially work efficiently at higher temperatures.

"One of the advantages of solid-state energy converters are that they can operate at higher temperatures with lower maintenance costs because they have no moving parts," Henry says. "They just sit there and reliably generate electricity."

Thermophotovoltaic cells offered one exploratory route toward solid-state heat engines. Much like solar cells, TPV cells could be made from semiconducting materials with a particular bandgap -- the gap between a material's valence band and its conduction band. If a photon with a high enough energy is absorbed by the material, it can kick an electron across the bandgap, where the electron can then conduct, and thereby generate electricity -- doing so without moving rotors or blades.

To date, most TPV cells have only reached efficiencies of around 20%, with the record at 32%, as they have been made of relatively low-bandgap materials that convert lower-temperature, low-energy photons, and therefore convert energy less efficiently.

Catching light
In their new TPV design, Henry and his colleagues looked to capture higher-energy photons from a higher-temperature heat source, thereby converting energy more efficiently. The team's new cell does so with higher-bandgap materials and multiple junctions, or material layers, compared with existing TPV designs.

The cell is fabricated from three main regions: a high-bandgap alloy, which sits over a slightly lower-bandgap alloy, underneath which is a mirror-like layer of gold. The first layer captures a heat source's highest-energy photons and converts them into electricity, while lower-energy photons that pass through the first layer are captured by the second and converted to add to the generated voltage. Any photons that pass through this second layer are then reflected by the mirror, back to the heat source, rather than being absorbed as wasted heat.

The team tested the cell's efficiency by placing it over a heat flux sensor -- a device that directly measures the heat absorbed from the cell. They exposed the cell to a high-temperature lamp and concentrated the light onto the cell. They then varied the bulb's intensity, or temperature, and observed how the cell's power efficiency -- the amount of power it produced, compared with the heat it absorbed -- changed with temperature. Over a range of 1,900 to 2,400 C, the new TPV cell maintained an efficiency of around 40%.

"We can get a high efficiency over a broad range of temperatures relevant for thermal batteries," Henry says.

The cell in the experiments is about one square centimeter. For a grid-scale thermal battery system, Henry envisions the TPV cells would have to scale up to about 10,000 sq ft (about a quarter of a football field), and would operate in climate-controlled warehouses to draw power from huge banks of stored solar energy. He points out that an infrastructure exists for making large-scale photovoltaic cells, which could also be adapted to manufacture TPVs.

"There's definitely a huge net positive here in terms of sustainability," Henry says. "The technology is safe, environmentally benign in its life cycle, and can have a tremendous impact on abating carbon dioxide emissions from electricity production."

This research was supported, in part, by the U.S. Department of Energy.

Published May 2022

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