Category Archives: Capacitors

Motor Run & Motor Start Capacitors

Electric motors exploit the interaction between two magnetic fields for rotating a shaft. The stator windings generate one of the fields, and the rotor windings provide the other. In some DC motors, permanent magnets replace one of the windings, while the commutator, whether brushed or brush-less, changes the direction of the current in the other winding to continuously alter the interaction between the two magnetic fields to allow the motor to rotate. In three-phase AC motors, the interaction between Read more [...]

Seaweed For Making Superconductors and Supercapacitors

Seaweed, a kind of algae, and a part of cuisines in many parts of the world could be worked to supply power to electronics and other devices. Researchers have developed a material from seaweed to produce better superconductors, batteries, and fuel cells. The research has been presented at a meeting of the American Chemical Society (ACS) on April 5, 2017. Dongjiang Yang, PhD, a team member explains that carbon rich materials offer the most efficient energy storage solutions. Since the team Read more [...]

What are Light-Emitting Capacitors good for?

HLEC, or Hyper-elastic Light-Emitting Capacitors are good for making electroluminescent skin for robotics, and you can do a lot with them. That is according to Dr. Rob Shepard of Cornell University and his team of graduate students, who have published a paper on the electroluminescent skin they have developed recently. The team was inspired to develop the electroluminescent skin by observing several cephalopods such as the Octopus. According to the team, their material can change its color, just Read more [...]

Mica Capacitors : Why should I use them?

Mica, a phyllosilicate, is a group of hydrous potassium/aluminum silicate material. It is a rock-forming mineral exhibiting a two-dimensional sheet or layer structure. That means it is possible to split mica into thin sheets. The biggest advantage of mica is the excellent stability of its electrical, chemical and mechanical properties. This property makes mica a suitable material for use as a dielectric when making highly stable and reliable capacitors. Silver-mica capacitors are useful at high frequencies, Read more [...]

Powerful Energy Storage with Micro-supercapacitors

People have been trying to use supercapacitors to supplement batteries. Although capacitors do store energy, unlike batteries they charge up fast and discharge the energy stored quickly, such as in a camera flash. Common lithium-ion batteries take time to charge up and discharge according to requirement of the load. However, technology is catching up fast and new type of micro-supercapacitors is rivaling commercial supercapacitors in terms of storage capacity and power delivery similar to batteries. At Read more [...]

What are Polymer and Hybrid Capacitors?

The growing complexity of active electronic components and their applications has resulted in the use of different types of passive components, especially capacitors. The advances in conductive polymers now offer a universe of capacitors for embedded systems applications and others. Some advanced capacitors use conductive polymers for their electrolyte. Others such as hybrid capacitors use the conductive polymers in conjunction with a liquid electrolyte. Both these polymer-based capacitors offer Read more [...]

Why Do ICs Need Bypass Capacitors?

Any electronic design engineer will vouch for the necessity of supplementing integrated circuits on their PCB with bypass capacitors, although they may not understand the reason to do so very well. As a rule of thumb, engineers provide every IC with a 0.1µF ceramic capacitor next to its power pins in each circuit board they design. Along with proper PCB layout techniques, adding a bypass capacitor improves circuit performance and maximizes the efficacy of the ICs. The trouble lies with transition Read more [...]

Why Does My Motor Need A Capacitor?

If you are using an AC pump to raise water from a sump to an overhead tank, chances are it uses a squirrel-cage type motor, which needs a capacitor to make it work. This is true for single-phase motors, where the capacitor creates an artificial second phase necessary to generate the rotating magnetic field and make the rotor start spinning. Once the rotor starts rotating, the interaction between the stator and rotor keeps the magnetic field spinning. A single-phase motor has a primary winding Read more [...]

The Ripple Rating of a Capacitor

Engineers do not prefer having ripples in their circuits and do their best to minimize its effects. For example, an AC source delivers power to an AC-DC converter that subsequently converts it to a steady DC output. It can be very inconvenient if the output were to have any source AC power appearing on top of the DC output in the form of small, frequency dependent variations. However, ripple may not be considered evil in all cases, as some digital signals could be useful to engineers as a necessary Read more [...]

Building a UPS with Raspberry Pi and Supercapacitors

It is always a dilemma when integrating a Raspberry Pi (RBPi) Single Board Computer into a project that works on the mains voltage and the RBPi has to turn it on or off. The difficulty is in deciding whether to power the RBPi separately or maybe power it from a UPS. Lutz Lisseck solved the problem in an ingenious way. He was looking for a way to shut down his RBPi gracefully, after it had turned off his ambient-lamp. Since the lamp operated directly from the mains and Lutz wanted to turn it on/off Read more [...]