Our Assembly and Testing Solutions for Power Electronics and Batteries

Alexander Denk: Power electronics control the entire drivetrain of an electric vehicle. They consist of three main components – the first is the inverter, which converts the battery’s DC voltage into AC voltage for the motor. The second component is the AC charger, or more precisely the charging unit. When charging via a socket or wallbox, AC current is supplied, which this unit converts into DC to charge the battery. The third component is the DC/DC converter, which, for example, supplies the 12 V on-board electrical system.

Alexander Denk: These components are highly complex assemblies. Power electronics are a key technology for the successful transformation of the automotive industry. At the same time, innovation cycles are becoming increasingly shorter. This drives efficiency while reducing power losses – and companies must be able to adapt to these changes.

Alexander Denk: A collaboration with Sonplas, of course (laughs). But seriously, we provide assembly and test systems specifically for this sector. For example, we plan and implement line concepts ranging from prototype builds to fully automated production systems, with typical cycle times between 20 and 300 seconds for applications such as inverters, converters or on-board chargers. These systems are designed to handle typical workpieces weighing between 2 and 25 kilograms.

Alexander Denk: It depends. Depending on the project requirements, our experts either draw on a broad portfolio of proven and, in some cases, patented processes – or develop custom workflows together with the customer as a tailored solution. This can significantly reduce production costs. Thanks to our extensive experience in electronics manufacturing, we also develop and build power stages in our own laboratory. And of course, we support prototype development if companies do not have the necessary equipment to produce them in-house.

Alexander Denk: Exactly. The key is to tailor each process precisely to the specific requirements. For manufacturers, however, this often involves significant effort. In addition, most suppliers of assembly systems do not offer testing themselves – either due to a lack of expertise or because they do not have the necessary equipment to fully cover the required tests. We have built up extensive know-how in this area within a short time and can now demonstrate several highly successful references. Customers trust our specialists – their experience, their comprehensive consulting and their assessments. This provides clear added value, as we offer a high level of confidence, especially during often uncertain development phases.

Alexander Denk: An important segment of our portfolio is end-of-line (EOL) test systems. A key feature of these systems is their modular design, allowing them to be flexibly adapted to individual requirements. Depending on the application and the specific test scope, our experts configure the appropriate modules from a modular system. For different product types, customers receive a base machine with the corresponding test adapter, resulting in significant cost savings.

Alexander Denk: Depending on requirements, the system can perform leak testing – typically using air – or handle flashing to apply calibration data or install the operating system. In addition, the test station enables customers to verify communication, for example via CAN or Ethernet. Ultimately, the system allows measurement and calculation of currents, power and efficiency, as well as indirect speed determination.

Alexander Denk: We also provide manufacturers with reliable solutions for safe launch tests, as well as for cold and hot testing of PCBs and complete assemblies. To ensure that electric and hybrid vehicles operate with maximum efficiency, not only the electric motor and battery must be kept within an optimal temperature range, but also the power electronics. With our systems, tests can be performed in temperature ranges from -40 to +90 degrees Celsius. In addition, they are capable of simulating various environmental conditions, for example using our in-house developed and certified thermal chamber. Long-term tests prior to planned series production can also be implemented, allowing products to be tested even more intensively.

Alexander Denk: That depends on the test system and the specific application. Electric vehicles have two on-board electrical systems – the high-voltage system for the drivetrain and the low-voltage system for vehicle electronics such as radio, lighting, windshield wipers or cruise control. A high-voltage battery is used, which supplies the 12 V battery for the vehicle electronics via a converter. The voltage levels have increased significantly over time – from around 48 volts in the early days to 800 volts today, with a trend towards 1,200 volts. As power demands continue to rise at the same current levels, systems must be able to safely handle these high and increasing voltages. Many tests are performed directly on live components of the power electronics. Therefore, once testing is completed, it must be ensured that the test specimen is no longer energized when the operator opens the safety door – otherwise this could pose a serious safety risk.

Alexander Denk: We provide a comprehensive safety concept that addresses potential hazards and minimizes risks. This starts with the selection of suitable installation materials such as cables, terminals and other components. Our systems safely handle all voltage levels, as well as peak currents exceeding 800 amps and the corresponding high power levels.

Alexander Denk: We offer assembly and testing from a single source, efficiently combining both disciplines within our solutions. Thanks to our proven network of selected and reliable partners, customers receive a complete package with a single point of contact. This shortens coordination paths, reduces organizational effort and avoids interface issues. We also provide training for our customers on our systems. In addition, our modular design allows test systems to be flexibly adapted to increasing requirements or changing products.