Power resistors are utilised in power technology and distribution, handle methods, and other electrical power program applications. Examples include load banking companies, grounding resistors, and dynamic braking resistors.
There are many potential producing strategies but resistors based mostly on thick film technologies substrates provide large integration density that makes it perfect for purposes the place substantial electrical power dissipation is required in a little region. The content traits of the substrate imply it is an outstanding match with the aluminium materials in heatsinks and it is chemically inert and mechanically stable.
Special carrier components, such as Silicone Nitrite may be utilised to make a power resistor in the kW range. However, these materials can be high-priced and could cost as a lot as € two hundred every single in purchase quantities of a handful of thousand units, in addition the expenses for processing with Thick Movie supplies. This signifies such resources are usually only utilised for specialists programs.
Examples include a power resistor with dimensions one hundred mm by fifty mm on one mm thick Alumina Ceramic that can manage 500 W offered the factor temperature is held consistent at all around sixty °C. Resistor load financial institutions with energy rankings as high as twenty five kW @ one hundred forty kVolts could be produced.
When created appropriately making use of proper resources Thick Film electricity resistors can deal with numerous kW of electricity dissipation but they create massive amounts of warmth which will fracture the resistor provider plate if not kept beneath control. Mindful consideration of the software and thermal administration is for that reason needed before committing to the resistor style and producing approach.
One particular answer to the resistor thermal overload problem is to submerge the electricity resistor in high quality mineral oil in a heat exchanger. The exchanger need to be developed appropriately to make sure it is capable of removing the warmth generated so the oil temperature is held continuous at a protected stage.
Appropriate administration of the heat exchanger is needed as Impurities in the kind of carbon deposits are created in high voltage oil cooled systems and until oil is filtered and / or in any other case retained at large top quality via regular replacements, this kind of impurities will develop to a amount the place 1 or much more resistors are shorted out of the loop and therefore lead to other resistors in the chain to overload and fracture. Yearly oil changes are for that reason suggested.
A electrical power resistor produced using thick film technologies supplies a fairly minimal expense, higher functionality, modest footprint solution for a vast assortment of electrical power applications. However, mindful thing to consider of thermal problems is necessary in the course of the layout section to make certain trustworthy operation. Learn more about high power resistors here.