Power resistors are employed in power era and distribution, handle methods, and other electrical power method purposes. Illustrations incorporate load banking institutions, grounding resistors, and dynamic braking resistors.
There are numerous prospective producing tactics but resistors dependent on thick film engineering substrates provide substantial integration density that can make it perfect for applications exactly where higher energy dissipation is essential in a tiny area. The content attributes of the substrate suggest it is an exceptional match with the aluminium material in heatsinks and it is chemically inert and mechanically stable.
Special provider components, these kinds of as Silicone Nitrite could be utilised to generate a energy resistor in the kW selection. However, these materials can be high-priced and may price as a lot as € 200 each in purchase portions of a few thousand models, in addition the fees for processing with Thick Movie components. This implies this kind of supplies are usually only used for professionals apps.
Examples consist of a energy resistor with dimensions a hundred mm by fifty mm on one mm thick Alumina Ceramic that can take care of 500 W presented the factor temperature is kept constant at around 60 °C. Resistor load banks with electrical power scores as higher as 25 kW @ a hundred and forty kVolts may possibly be created.
When produced appropriately using proper resources Thick Film energy resistors can manage a number of kW of electrical power dissipation but they generate huge quantities of heat which will fracture the resistor carrier plate if not held below control. Cautious thought of the application and thermal management is for that reason needed before committing to the resistor layout and production procedure.
One particular remedy to the resistor thermal overload problem is to submerge the power resistor in high grade mineral oil in a warmth exchanger. The exchanger should be created appropriately to make certain it is capable of taking away the warmth created so the oil temperature is stored consistent at a risk-free amount.
Appropriate administration of the heat exchanger is necessary as Impurities in the form of carbon deposits are produced in large voltage oil cooled methods and except if oil is filtered and / or in any other case retained at substantial high quality via normal replacements, this sort of impurities will construct to a stage exactly where a single or much more resistors are shorted out of the loop and as a result trigger other resistors in the chain to overload and fracture. Annually oil modifications are therefore suggested.
A electrical power resistor manufactured utilizing thick movie technology offers a reasonably lower price, higher efficiency, tiny footprint solution for a wide assortment of power apps. However, cautious consideration of thermal concerns is required in the course of the design stage to ensure dependable procedure. Learn more about power resistor here.