Development of High Power, High Voltage Magnetic Components and Encapsulated Inductor for Power Propulsion Unit

Abstract

As electrical power propulsion units (PPU) have become a major part for the space industry the need for higher power components at higher voltages has increased. This digest is based on an European Space Agency (ESA) development contract: “Planar and encapsulated SMD inductive electronic component qualification”, contract number: “4000122089/17/ NL/CRS”. There are two design and development objectives of this project. First, high power high voltage (HPHV) components for the PPU and second being encapsulated inductive components. The project underwent four phases such as component specification, component design, production and verification testing. Firstly, a 5 kW case study of PPU technology was made to create a specification for the PPU inductive components. Thereafter, the electrical design was completed. This was followed by the production of the PPU components. The PPU components were manufactured and finalized by verification testing consisting of power burn-in, mechanical shock, vibration, and temperature loaded stress tests. The PPU components have been designed using the planar ferrite cores, which enables a high power component with a relatively low build height. The disadvantage of the planar core is the lack of bobbin, therefore aircoil winding technology has been utilized which gives a large design freedom. The transformer was designed and manufactured with a coil consisting of flat wire windings stacked on top of each other, while the inductor was designed and manufactured using copper foil windings. In order to develop encapsulated magnetics a collaboration with the company Sintex A/S was established. Sintex A/S specializes in making high precision custom shapes in metal and soft magnetic composite materials. In this collaboration, Sintex A/S is providing expertise and manufacturing of the ferrite component of the encapsulated inductor. Both the HPHV components and the encapsulated inductor have been designed, manufactured and verified by testing.