Showing posts with label Capacitors. Show all posts
Showing posts with label Capacitors. Show all posts

Tuesday, February 07, 2017

Reliability in Axial and Radial Plastic Capacitors

The Axial capacitors like Metalized Polypropylene MPP are more reliable in comparison of their radial counterparts of same voltage rating.

Also note 440V AC Continuous rating reads and translates differently than 630V DC Max. Overrating is an important step in reliability for engineers.

High Energy Circuits

Radial plastic caps, in mass production, due to various inconsistencies in production or quality measurement, are not recommended for high voltage unless its is a Manufacturer known for long term reliability and quality track record.

Reliability in Axial and Radial Plastic Capacitors

The radial caps when being wound, stretches the film/dielectric or weakens the dielectric at some areas as the turn is sharp, top/bot. This is possible unless the winding machine relaxes strain around the turns. In a Axial that may not be a problem as the film has more uniform stretch. The other reason  could be that the Film is wrapped a little on corners or compressed on epoxy impregnation. It could also be low quality non-uniform PP material.

Power Electronics & Solar Energy

Components Manufacturers have to spruce up a Raw-Material and Component Quality, not by red-tape but by actually improving the manufacturing and procurement processes, as the quantities involved are huge.

Sunday, January 15, 2017

ViPEC Network Analyzer

ViPEC is a powerful tool for the analysis of high frequency, linear electrical networks. It takes a schematic description of the electrical network and performs a linear analysis in the frequency domain.

ViPEC Network Analyzer

The output is in the form of port parameters (S, Y or Z) with results presented on a user defined grid, Smithchart or table. It can also be used to compute other characteristics like stability factors and group delay.

ViPEC Network Analyzer

ViPEC supports various lumped elements (capacitors, resistors etc.) as well as distributed networks like transmission lines, microstrip and stripline structures. Two port data files are also supported (e.g. the 2-port frequency parameters of various RF transistors as supplied by the manufacturer). The component library is under constant development with new elements added at regular intervals.

Thursday, September 05, 2013

Electric Double Layer Capacitor - EDLC

The Electric double layer capacitor has the main use of a Charge Reservoir. That means a large amount of electrical charge in a small footprint.

These charge/discharge quickly unlike the battery, There is no Electrical Energy to Chemical Energy Transformation and back, like in batteries. It may need caution in design and usage as they may carry a lot of punch.

Also known as Ultracap, Goldcap, Supercap - Electric double layer capacitor, In Farads, like batteries, Energy Reservoirs or eFlywheel.

In Product Safety terms; The Battery has a Internal Resistance, but a Supercap does not. When used in Values like 100F and is fully charged, an Internal or External Breakdown of Insulation or Short Circuit may Occur. The Heat Generated is Enormous. Murphy's Law says such things happen..

Supercap at Wikipedia

Electric Double Layer Capacitor (EDLC) or SuperCapacitor

DLCAP - Electric Double Layer Capacitor - Nippon

They have a range of Supercapacitors upto 2500F at 2.5V and Modules like 400F and 15V. There are two types Prismatic and Cylindrical. In comparison to batteries - multi-million cycles of charge-discharge is possible.

EverCAP - Double Layer Capacitors - Nichicon

They have two types, High Power Density for a large current discharge. High Energy Density for a long backup time. Over a million Charge/Discharge cycles. High Efficiency. Capable of fully discharging to zero volts.

Some things to note for a design engineer. The EDLC or Electric Double Layer Capacitors ...
  • Specified Endurance and end of life.
  • Excess Vibration can alter Specs.
  • Caution - The maximum temperature.
  • Specs are dependent on Temperature.
  • Maintain Low ripple current on Charge/Discharge.
  • It is Polarized like a Electrolytic cap.
  • Not Hot parts or Heatsink near cap.
The Double Layer Capacitors developed by WIMA are storage capacitors with highest capacitance values in the Farad range.

GTO Capacitors - WIMA

They are among others suited to serve as batteries, can deliver considerably higher currents for a short time, however, and are maintenance free.

SuperCapacitors - WIMA

These EDLC supercap has one-tenth of energy, but delivers over 10 times of power due to ultra low ESR. In Comparison with a Battery. A Lifetime of over 500,000 cycles.

Xelled Supercapacitor - Vinatech

Some Specs
  • Rating 2.5V / 2.7V
  • High power density (low internal resistance)
  • High electrical current, instant power back-up applied

Read more about Supercapacitors.

Monday, May 09, 2011

JTIsoft from Johanson Technology

JTIsoft from Johanson Technology is comprised of two advanced design simulation software, MLCsoft and MLIsoft. It provides complete S-Parameter and SPICE modeling data on Johanson's line of RF multilayer ceramic capacitors and inductors over the frequency range of 1 MHz to 20 GHz.

JTIsoft Modeling Overview

 JTIsoft Modeling Overview

MLCsoft and MLIsoft provide highly detailed graphical plots of device performance data in two basic formats over a user specified frequency range. The chart displays are instantly updated as the user makes capacitance or frequency changes. Smith chart displays of both impedance and S11/S22 are available as point plots, line plots, and line-point plots.

JTI specializes in the design and manufacture of high quality ceramic components for RF/Wireless and Microwave applications.

Johanson Technology - RF Ceramic Components

Johanson Technology
4001 Calle Tecate, Camarillo, California 93012, USA.