Calibrating Photovoltaic Cells

The basic function of a photovoltaic cell is to convert input — sunlight energy expressed in irradiance (W/m2) — into output — useable electrical power — with as little loss as possible. To quantify the ability of the system to accomplish this conversion, one can simply compare the output to the input by forming a ratio of the two. This ratio, expressed in percentages, is known as the power conversion efficiency (PCE) of the device and it is a key parameter of electrical performance. Since the PCE is used to compare the performance of photovoltaic devices, it is critical that accurate estimates be made for the PCE. The estimate is dependent on knowing, with a high degree of accuracy, the actual conditions, including irradiance and cell temperature, under which the parameter is measured.

Posted in: Articles, Features, ptb catchall, Photonics


Performing Accurate Multi-Paction Measurements

Multi-paction effects can impact microwave components in high-power satellite communications (sat-com) systems. The nonlinear break-down-voltage phenomenon occurs in high-vacuum environments above a certain threshold voltage, and can degrade the performance of RF and microwave components or, in extreme cases, damage the components or the system. Although multi-paction effects are often difficult to predict and measure, properly equipped test systems with dedicated software can accurately identify microwave components that may multi-pact, effectively screening them to avoid damage in a deep-space application.

Posted in: Articles


Controlling Robotics Precisely With Haptic Technology

Robots are capable of very precise motion, but must be guided with precision in order to fulfill their potential. Consider the task of guiding a robotic surgeon’s arm to suture a wound or insert a catheter. A human surgeon, with all his or her knowledge and experience, is required to practice where to probe, cut, or sew before he or she can develop the necessary skills to make a clean suture with the right degree of tension at the right depth or an incision of the right depth. In contrast, a robotic surgeon’s arm can move more consistently and accurately than that of the best human surgeon.

Posted in: Articles, Motion Control


Generating Energy Innovation: Disrupting the Alternatives

In just the last few years, innovation in alternative-energy technologies have gained significant footholds in product development lifecycles and are rapidly changing our individual roles as energy consumers and producers. Out of the box thinking and breakthrough discoveries are on the rise in solar, wind, biofuel, and other alternative-energy technologies. 

Posted in: Features, GDM, Articles, Biomass, Energy, Energy Efficiency, Renewable Energy, Solar Power, Wind Power, Alternative Fuels, Green Design & Manufacturing, Greenhouse Gases


Optimized Power Devices Enable Energy Efficient Solar Inverters and Micro-Converters

As the demand for greener appliances and consumer products soars across the globe, and energy savings becomes a global phenomenon (and necessity) in residential and commercial environments, solar and wind power technologies have begun to proliferate in cities and states around the world.

Posted in: Features, GDM, Articles, Energy, Energy Efficiency, Renewable Energy, Solar Power, Wind Power


Wireless Sensor Technology for Real-Time Applications

The ability to make real-time decisions based on pressure, temperature, or flow measurements while a process is running can provide significant advantages in a measurement and control system. These advantages can be expressed in different ways such as cost savings through improved resource management, or reduced reliability upon mobile workers. While measurement data can be used to dynamically control a process, it can also be displayed over a network to allow remote monitoring of the process status in real time. Rising pressures, temperatures, or vibration intensity can easily be adjusted if the appropriate personnel are aware of faulty conditions. As data is collected for process control or a SCADA system, it can also be archived for future reference when a review of process trends could provide additional improvements.

Posted in: Articles


Programming Network Processors Made Simple

The telecommunications industry’s continuous strive for higher performance has spurred innovations in processor architectures. The general trend has been to go parallel; adding more cores to a single processor device and then dividing tasks between them. This has resulted in a more complex environment for software engineers to master. But does this mean that the programming of next-generation network processors (NPUs) has to be difficult? Not necessarily.

Posted in: Articles, Articles


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