In the electronics industry of the Federal Republic of Germany 286,000 employees are working in assembly twice as many as in the automotive or machine building industries.

Over the course of the last decade 3D printing has become a more established technology in terms of prototype development (rapid prototyping). The current effort is focused on transferring this knowhow into a product driven approach in order to manufacture even small batch sizes more economic. In terms of this work, this idea is adapted for the development of injection molds (rapid manufacturing). Hereby, a hardened polymer is used to create a forming cavity instead of tool-steel. In order to fulfil the mechanical process requirements of micro injection molding such as form stability under temperature and pressure this cavity is nevertheless integrated into a metal housing. A first set of experiments has been carried out using this develop mold to verify the capabilities of the developed prototype as well as molding process. Based on these first results, an optimization is carried out to improve the next iteration of this molding tool.

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This paper deals with the harmonic current emission of large self-commutated PV inverters. It disproves with new measurement results that modern inverters behave as current sources for harmonic currents, which is the general idea behind the accepted grid codes. Furthermore it presents new approaches to quantify the contribution of grid voltage distortion to measured harmonic emission under real world conditions. The conclusions which are drawn at the end of this paper are based on high precision harmonic current measurements, which have been carried out for a central inverter with a nominal power of 225 kVA. The harmonic emissions were measured for different types of grid configurations and background distortion.