How overmoulded busbars are powering the future in modern electric transportation applications
How overmoulded busbars are powering the future in modern electric transportation applications.
The integration of overmoulded busbars into modern electrical applications has revolutionised the way we approach electrical connectivity and power distribution in automotive and industrial applications. These components are now essential for connecting the battery to the inverter and into the motor. Here, we discuss the basics, benefits and production of overmoulded busbars.
ROLE AND CHALLENGES OF OVERMOULDED BUSBARS
From the beginning of e-mobility, overmoulded busbars have been indispensable in various electrical applications due to their ability to provide reliable and efficient connections. The constant aim to increase efficiency of the drivetrain causes ever greater power density, which leads to higher requirements for the connections between batteries, DC-to-AC power inverters and AC traction motors. This trend has a huge impact on the design of the connectors.
With higher power density the form factors of the copper busbars and the conductive surface areas need to be increased without violating the limited installation space. Additionally, the reduction of air and creep phenomena is key to prevent breakdown of insulation and to limit loss in power. Increasing junction temperatures is also a challenge and must be considered in the design of the connectors, polymer selection and sealing technique. All these increased requirements must be met, without neglecting the weight, size, and the feasibility of the overmoulded busbars.
UNPACKING THE BENEFITS
The advantages of overmoulded busbars are numerous. Their design allows complex geometries that are crucial in today’s compact electronic devices. This capability ensures excellent form and positional accuracy, enabling precise and reliable connections. Additionally, the high energy densities achievable with overmoulded busbars make them ideal for applications where space is limited but power requirements are high.
The evolution from traditional wound stators to hairpin technology has had a significant impact on busbar design. Hairpin stators, with their precise and compact shape, improve the overall efficiency and power density of electric motors. This evolution has led to improvements in busbar manufacturing and assembly processes, allowing more efficient and streamlined production.
CONSTRUCTION AND MANUFACTURING
The construction of overmoulded busbars involves several components and manufacturing processes. Typically, the busbars are encapsulated in a protective material through an overmoulding process that provides insulation and protection from environmental factors. The process involves placing the busbar in a mould and injecting a thermoplastic material around it. This technique not only protects the busbar but also increases its mechanical strength and durability. Depending on the busbar application oil tightness is also crucial, which can be ensured with potting or seal-assembly processes.
Given the diversity of applications, manufacturing processes may vary. Common techniques include precision stamping, overmoulding, and various finishing processes to ensure optimum performance and reliability.
DESIGN FOR MANUFACTURING
As the demand for sophisticated electronic systems increases, the importance of Design for Manufacturing (DFM) cannot be overstated. DFM principles ensure that products are designed with manufacturability in mind, reducing costs and improving efficiency. Wieland’s extensive experience in applications and manufacturing processes plays a critical role in optimising busbar designs for production. By incorporating DFM principles, Wieland is able to produce high-quality overmoulded busbars that meet the stringent requirements of modern electrical applications.
EXPERTISE IN ELECTRICAL SOLUTIONS
Wieland has a rich history in the field of components, starting with its expertise in bearings for the automotive sector. Over the years, the company has expanded its focus, leveraging its extensive knowledge to develop innovative solutions for e-mobility.
Today, Wieland is at the forefront of innovation with its overmoulded busbars, offering solutions that meet the highest standards of quality and performance. To reach this position, Wieland is continuously expanding its know-how and investing in machinery for automated manufacturing, assembling, and EOL-testing of overmoulded busbars. The company’s capabilities in this area demonstrate its commitment to advancing technology and supporting the evolving needs of the electrical and automotive industries.
PIONEERING THE FUTURE OF E-MOBILITY
With their complex geometries, high energy densities, and robust construction, these components are integral to the efficiency and reliability of today’s electrical systems. Wieland’s history and ongoing commitment to innovation position the company as a leader in the field, continually advancing the capabilities of overmoulded busbars to support the future of e-mobility and beyond.
By continuously pushing the boundaries of what’s possible, Wieland ensures that overmoulded busbars will remain a cornerstone of modern electrical applications, driving the next generation of technological and energy solutions.
Hans-Christian Hecht, Technical Marketing eMobility at Wieland.
