Tips to Make the Best of Aluminum Electrolytic Capacitor
One of the most popular components of power equipment is the aluminum electrolytic capacitor due to low cost. These devices may be sufficient as long as you consider lifespan and temperature extremes.
Here are other essential details about aluminum electrolytic capacitors:
Material Quality The most basic elements of an aluminum electrolytic capacitor include foil, paper and an electrolyte, which eventually evaporates and weakens performance. The danger of using a failed capacitor is that it can emit a combustible and corrosive gas. The typical lifespan of a capacitor is 1,000 hours when operating at 105 degrees Celsius. If the capacitor is associated with an LED light bulb designed to last 25,000 hours, then the temperature must be lowered to 65 degrees Celsius. The problem, though, is that the ambient temperature of such an application can surpass 125 degrees Celsius. Aluminum electrolytic capacitors make cost effective short-term replacements for LED bulbs.
Precautions It's important not to assume you need to raise the voltage rating of the capacitor, which can lead to higher equivalent series resistance (ESR). High ripple current stress influences extra internal power loss despite raising capacitor temperature. The result of higher temperature is increased failure rate.
Aluminum electrolytic capacitors tend to operate around 80% of rated voltage. Such capacitors that are run at cold temperature will lead to boosts in ESR levels by a magnitude of -40 degrees Celsius, which affect performance in multiple ways. The switching power supply output ripple can rise dramatically. The control loop gain can also rise to a level that leads to unstable power, so the control loop must be adjusted for higher temperature.
Assess Your Needs You'll have to determine if price or quality is your priority. The low cost option, again, is the aluminum electrolytic capacitor, but it will limit durability and may have other negative issues. If you care more about longer life expectancy, then you need to make temperature adjustments by derating the voltage appropriately for cooler conditions. In order for desired results, you will need to have a clear understanding of ESR, the control loop and ripple specifications.