Energy in the form of electricity is what drives our modern economy, powering everything from communication, transportation and food production to scientific research, medicine and exploration. The lifecycle of an electric current includes generation by conversion of mechanical energy, transmission across power lines and delivery through stepdown transformers to power the device. To ensure the components that comprise the power grid work properly requires special design features that provide safety, reliability and longevity.
Specifically, proper electrical isolation is a key component that governs the continued efficacy of high voltage equipment, protecting against electrical shorting, discharge and faults. Fortunately, the solutions to many of these issues are within the arsenal of MG Chemicals’ product portfolio, such as dielectric materials, including coatings, resins and greases. The following paragraphs highlight how MG products are used in the energy industry, including actual case studies.
Coatings For Busbar Insulation
Busbars are critical components in power distribution units that carry large amounts of electricity to nearby receivers. They are strips of either copper or aluminum, often with irregular shapes, with a relatively large surface area. Compared to wiring, busbars can shuttle large amounts of electric current with very minimal leakage current, making them ideal materials for high and low voltage machinery. It is paramount; however, to properly insulate busbars to prevent shorts due to arcing or incidents such as dropping tools. Conventional solutions like Kapton and polyester tape work well; however, can be difficult to apply to complex geometries making it challenging for complete coverage. Epoxy powder coatings are superior in this respect; however, the process of applying this coating type is quite cumbersome and the coatings are quite brittle, leaving them prone to cracking and subsequent failure. Insulation coatings like the 4226A and 4228A are highly flexible, 1-component coatings with high dielectric strength that cure at room temperature. These coatings can be applied by dip or spray and can provide sufficient insulation for high voltage parts.
Resins for Circuit Breakers
An arcing chamber is a safety component of circuit breakers that extinguishes large voltage arcing faults by breaking them up into lower voltage arcs. At high voltage and current load, an arcing chamber helps prevent hazards such as electrocution and potential fires. Dielectric resin materials like our 832C and 832B are applied to add insulation within the chamber to any weathered plastics inside the housing. These 2-component epoxy systems are low viscosity and have a relatively long working time, allowing the user to apply it like a paint and build up ample film thickness to ensure sufficient dielectric protection for high voltage scenarios.
Dielectric Materials for Power Supplies
A power supply is a device that modulates electrical current from a generator to the correct voltage, current and frequency to power an instrument. Laboratory equipment, which relies on a very steady DC load for high precision measurements, often use portable power supplies during scientific expeditions that occur outside the comfortable confines of a modern laboratory. As an example, arctic water exploration uses very long probes that takes measurements deep below the ice and due to the length of the probe, experience voltage drops as the probe travels deeper underwater. An agile power supply that can adjust and increase DC output is needed here to ensure steady voltage over the length of the probe. Again, dielectric coatings like our 4226A, 4228A and dielectric grease like our 8462 are used in the design of switchgear and circuit breakers of power supplies to protect systems against overloads and faults.
Dielectric Materials in Battery Systems
Battery cells used in energy storage systems need to be electrically isolated from neighbouring cells within the battery pack to prevent short circuits. Typically, cells are wrapped with polyethylene terephthalate (PET) films; however, certain geometries such as prismatic or pouch arrangements can be problematic where films can delaminate around edges and seams. Cooling trays used to help maintain thermal stability are often coated with epoxy powder coating; however, temperature shifts felt by these parts can cause these coatings to crack, rendering them susceptible to arcing and faults. Again, electrically insulating coatings like 4226A and 4228A offer several advantages over materials like epoxy powder coating and PET films. Namely, their superior flexibility and adhesion assure they conform to the contours of the battery cells, whether prismatic or pouch arrangement and will not crack or delaminate, ensuring consistent coverage and electrical isolation.
