Power resistors are utilized in power era and distribution, manage techniques, and other power system apps. Illustrations incorporate load banking companies, grounding resistors, and dynamic braking resistors.
There are a lot of potential manufacturing tactics but resistors based on thick film technologies substrates supply higher integration density that helps make it best for purposes where higher energy dissipation is necessary in a modest region. The content attributes of the substrate suggest it is an outstanding match with the aluminium content in heatsinks and it is chemically inert and mechanically secure.
Unique provider materials, such as Silicone Nitrite could be utilised to make a power resistor in the kW variety. Even so, these supplies can be costly and may expense as significantly as € two hundred every single in order quantities of a handful of thousand units, additionally the costs for processing with Thick Movie components. This indicates this kind of supplies are generally only used for specialists applications.
Examples contain a power resistor with proportions 100 mm by 50 mm on one mm thick Alumina Ceramic that can deal with 500 W provided the aspect temperature is kept continual at about sixty °C. Resistor load banking institutions with electrical power ratings as high as twenty five kW @ a hundred and forty kVolts might be made.
When produced accurately employing acceptable materials Thick Film electricity resistors can handle numerous kW of energy dissipation but they produce large amounts of warmth which will fracture the resistor provider plate if not retained beneath management. Mindful thought of the application and thermal management is consequently essential just before committing to the resistor design and style and manufacturing procedure.
1 answer to the resistor thermal overload situation is to submerge the electrical power resistor in higher quality mineral oil in a heat exchanger. The exchanger ought to be made appropriately to make sure it is capable of eliminating the warmth created so the oil temperature is kept continuous at a protected level.
Appropriate management of the warmth exchanger is necessary as Impurities in the sort of carbon deposits are created in high voltage oil cooled techniques and unless of course oil is filtered and / or in any other case retained at large good quality through normal replacements, this sort of impurities will construct to a degree the place one particular or more resistors are shorted out of the loop and therefore trigger other resistors in the chain to overload and fracture. Annually oil adjustments are consequently suggested.
A electrical power resistor made employing thick movie technological innovation offers a fairly reduced cost, high efficiency, modest footprint remedy for a broad assortment of power programs. Even so, mindful thing to consider of thermal problems is essential for the duration of the design phase to guarantee trustworthy procedure. Learn more about power resistor here.