Electrical power resistors are utilised in power technology and distribution, manage methods, and other electrical power program purposes. Examples include load banks, grounding resistors, and dynamic braking resistors.
There are numerous prospective manufacturing methods but resistors based on thick movie technologies substrates offer higher integration density that can make it ideal for applications the place substantial power dissipation is necessary in a small spot. The materials attributes of the substrate indicate it is an outstanding match with the aluminium content in heatsinks and it is chemically inert and mechanically stable.
Special carrier resources, these kinds of as Silicone Nitrite might be utilised to produce a electricity resistor in the kW selection. Even so, these materials can be costly and may expense as significantly as € 200 every single in purchase quantities of a few thousand units, furthermore the costs for processing with Thick Film components. This means this kind of components are normally only utilised for specialists applications.
Examples consist of a power resistor with proportions a hundred mm by 50 mm on one mm thick Alumina Ceramic that can manage 500 W provided the aspect temperature is kept continual at about sixty °C. Resistor load financial institutions with electricity scores as large as 25 kW @ one hundred forty kVolts may possibly be manufactured.
When manufactured accurately utilizing proper resources Thick Film electricity resistors can handle a number of kW of power dissipation but they generate big quantities of heat which will fracture the resistor carrier plate if not stored beneath manage. Careful thought of the application and thermal administration is therefore necessary prior to committing to the resistor design and production procedure.
A single solution to the resistor thermal overload problem is to submerge the electrical power resistor in high quality mineral oil in a heat exchanger. The exchanger need to be designed correctly to guarantee it is able of removing the warmth generated so the oil temperature is kept continuous at a secure stage.
Acceptable administration of the warmth exchanger is necessary as Impurities in the sort of carbon deposits are produced in large voltage oil cooled techniques and except if oil is filtered and / or normally retained at high high quality through normal replacements, such impurities will build to a level exactly where one particular or much more resistors are shorted out of the loop and consequently result in other resistors in the chain to overload and fracture. Yearly oil modifications are as a result recommended.
A electrical power resistor manufactured utilizing thick film technological innovation provides a reasonably minimal value, higher overall performance, tiny footprint solution for a wide variety of power apps. Nonetheless, mindful thing to consider of thermal troubles is necessary during the layout phase to make sure dependable operation. Learn more about high power resistors here.