As the market demands for hybrid and electric vehicles continue to grow, a new generation of more efficient, higher-performance, more reliable, and environmentally friendly motors is bound to emerge. Axalta Coating Systems, a global leading liquid and powder coating company headquartered in Philadelphia, USA, has more than 70 years of experience in the development and production of high-quality insulation materials. One-generation motor design makes it coated with a smaller motor, larger output and longer mileage.
"We work closely with our customers to fully understand the needs of automotive component manufacturers, and always follow industry trends to predict trends in industry demand," said Dr. Christoph Lomoschitz, Global Product Manager, Axalta Energy Solutions. "Based on our in-depth research on motors and related industries, we have launched insulation system solutions for future requirements to help create a new generation of motors."
Axalta insulation coatings provide effective insulation protection for conductors, electrical steels, transformers, generators and motors. Axalta is currently the only supplier in the world that can provide a comprehensive and innovative environmentally friendly insulating liquid coatings portfolio.
Challenges of Innovative Design of New Motors to Insulation Products
The new motor is designed to meet two major needs, namely increasing power and reducing volume. In order to help achieve these goals, Axalta has introduced four unique types of insulation products to the market-silicon steel sheet paint, enameled wire paint, impregnated resin and cast resin. These four categories of products address specific challenges and support the manufacturing of existing and future new energy vehicles (NEVs).
New engines and their components need to be mass-produced, which must be taken into account during the initial design phase of the insulation product. "When developing new insulation products, we need to minimize curing, painting and dipping time to support the large-scale production of engines and other components," said Dr. Lomoschitz.
Innovative insulation system helps promote the application of new motors
Electrical insulation products (including coatings and resins) have four main applications in the motor field, and Axalta has its own solutions for each application.
Self-adhesive silicon steel sheet paint
The core of an engine is usually made up of thin punches designed to limit the negative effects of eddy currents. However, when the cores are connected by welding, screw fixing or interlocking buckle, even if they are coated with silicon steel sheet paint, weak points may still appear. At the same time, a conductive bridge will be formed at the traditional connection. Because the short circuit at the metal connection will increase the eddy current loss, the conductive bridge may reduce the engine efficiency.
In order to solve the above problems, Axalta's self-adhesive silicon steel sheet paint can bond the punches together. And because welding, interlocking, clamps, rivets, and screws can only provide local connections between individual interlayers, self-adhesion can also increase the hardness of the core and glue the entire laminate together. In addition, this bonding form reduces the noise emitted by the engine due to the inevitable vibrations during operation.
Corona-resistant enameled wire paint
Higher voltages, silicon carbide (SiC) technology, and inverters can cause partial discharges, which are small sparks that continuously hit the same point and cause local damage to the insulating material. The partial discharge will gradually destroy the impregnated resin, which will significantly reduce its protection of the enameled wire paint, and eventually lead to the partial discharge of the enameled wire paint. As the effectiveness of the main insulation decreases, electrical faults will also occur.
Based on Axalta's Voltatex® 7740 and Voltatex® 8534, and Voltatex® 8536, Axalta has introduced an enameled wire varnish that can withstand the effects of partial discharge and enhance the durability and reliability of motors. These three enameled wire lacquers are part of Axalta's Voltron ® system, which holds the first patent for a dielectric based on nanotechnology that improves corona resistance. Nanoparticles are the main mechanism for reducing electrical aging.
Frank Saborowski, product manager for enameled wire lacquers at Axalta Energy Solutions, said, "It is important that the enameled wire varnish is adapted to the impregnated resin covering the entire equipment to obtain the best wetting and compatibility. This is achieved through the special design of the surface of Axalta's Voltron® series of enameled wires. "
High thermal conductivity impregnated resin
New engines are usually aimed at increasing production and efficiency. To this end, one of the solutions is to increase the operating voltage of the motor, and the other is to replace the scattered round wire design with a hairpin flat wire design. The round wire design leaves a large gap, while the flat wire design can largely eliminate the gap and improve the engine's slot fill rate, thereby improving its efficiency. However, in order to achieve the same permeability as the round wire design, the development and use of impregnated resins need to be more advanced while reducing the gap.
The permeability of impregnated resin mainly depends on the viscosity of the resin, the surface tension of the system, the fluidity of the resin, and the size of the gap. Axalta's Voltatex® 4224 insulation impregnated high thermal conductivity impregnated corona-resistant resin, which has recently won the International Innovation Award, is a groundbreaking impregnated resin with significantly enhanced thermal conductivity and partial discharge resistance. Thanks to its extremely low viscosity and excellent flowability, Voltatex 4224 can effectively reduce the operating temperature without affecting processability. It can be used in standard impregnation processes to ensure excellent heat transfer from the copper winding to the core, making Thermal stress in engine components is smaller and performs better.
High thermal conductivity casting resin
In some high-performance motor applications, the advantages of cast resins are greater than impregnated resins. This type of secondary insulation material is more complicated to use, but the cast resin can provide better thermal conductivity and high stability.
Axalta has created many cast resins in the Voltacast series. These casting resins are polyurethane or two-component epoxy systems and consist of a resin and a corresponding curing agent. Depending on the constituent materials, the addition polymerization during chemical curing produces different grades of hard plastic materials, each of which has the end characteristics of a particular system. Cast resin is designed to protect all fixed electrical equipment, including transformers and ballasts, from the damaging effects of vibration, pollution, liquids, and thermal and mechanical stress.
Conclusion
Increasing the application of new energy outside the traditional internal combustion engine technology has become a global trend. To this end, lighter, cleaner, and more efficient hybrid and pure electric vehicles must be developed. Axalta's insulation products under Voltatex®, Voltaprem, Voltacast, and Voltabas and Voltron® brands are committed to promoting the electric vehicle field by helping future electric vehicle motors have greater power, higher efficiency, and the best reliability. Innovative development.
"Thanks to Axalta's extensive experience in providing first-class surface and insulation coatings to leading automotive manufacturers, Axalta is committed to introducing more groundbreaking technologies in this area. For Axalta Energy Solutions, the future It's here, "Dr. Lomoschitz concluded.