Connectors / High voltage connectors

Connectors and high-voltage connectors in e-mobility must connect drive components safely and reliably under sometimes critical boundary conditions. M.TEC meets the many development and production risks with proven systems and modern simulation tools. This is how successful developments of connectors are created.

Key challenges in development & design:

Tightness / sealing

High-voltage plugs must be sealed against penetrating media. If water, dust, salts, chemicals or other substances get into the plug, damage to the plug connection and adjacent components (short-circuit, corrosion, contamination of the contacts, etc.) can occur in the short as well as the long term. Thus, protection against failure must be guaranteed even after the connection has been disconnected and reconnected several times (e.g. during maintenance work). Typical sources of failure are unfavorable component tolerances, component distortion, the seal itself and the connection points between the contact and the encapsulating plastic.

Interaction of tolerances, warpage, design and production

With early tolerance analyses and filling simulation calculations to reduce component distortion, M.TEC reduces the project risks already in the concept phase. With our know-how in the field of sealing materials, geometric design and computer-aided design, M.TEC develops functionally reliable seals. This includes the consideration and selection of suitable production concepts and processes (overmolding of contacts, subsequent joining).

Production - injection molding, joining

With connectors, all aspects of the manufacturing concept have a major influence on component quality. Above all, the fundamental question of whether contacts are overmolded or subsequently joined is important. When overmolding metallic contacts, the mold technology is particularly complex; the contacts must be fixed precisely and securely in the mold, and the metal elements may have to be tempered. The precision of the molded part is decisive when subsequently joining or needling the contacts. This includes very low component distortion and high-precision production of the contact windows.

Systematic development for safe production

M.TEC supports with experience and know-how from development and production in deciding which process is best suited for the respective connector in total. To this end, M.TEC systematically develops solutions and evaluates the development results with filling simulation calculations and finite element analyses.

Interactions between materials

As hybrid components, connectors are made of different materials. These are mainly metals, engineering thermoplastics and elastomers or silicone in the sealing area. These materials have very different material properties. These include the coefficient of thermal expansion and different material behavior under mechanical stress (creep behavior of plastics). Possible damage to connectors includes stress cracks and component distortion, which lead to poor fitting of the mating partners, contact interruptions and leaks.

Risks due to different material properties

M.TEC knows the characteristic features of the different materials and the challenges in the manufacturing processes. During development, we incorporate these important aspects at the design level and check the component concepts with calculations such as filling simulations and finite element analyses. For the typical fiber reinforced materials, M.TEC transfers the process-related fiber orientation from the filling simulation to the finite element analysis, since the fiber orientation influences the component properties.

The knowledge of the interactions and the targeted use of the simulation tools is an important key in the development of solid connectors.

Service life

High-voltage connectors must be fail-safe throughout their entire service life. In the event of a functional failure, high repair costs are incurred; fundamental design errors or production faults can lead to recall actions. 

High-voltage connectors are exposed to high mechanical stresses during installation in the vehicle and during operation (plug forces in production, vibrations and temperature changes in operation). In addition, there are environmental influences from media such as water, dirt particles, salts and chemicals as well as climatic influences. 

Consider function and production process

In development, the loads during the service life must be taken into account as well as the requirements of robust large-scale production. The interaction of the different materials (thermoplastics, metals, elastomers) makes this multidimensional consideration particularly important in development and component design. M.TEC combines the knowledge of component design with process engineering to develop connectors with a long service life that can be manufactured efficiently and robustly at the same time.