2. Power Package Electrical Isolation Design

Power Electronics packaging consists of power semiconductor devices, power integrated circuits, sensors, and protection circuits for a wide range of power electronics applications (Trends in analog and power packaging, 2009; Challenges of power electronic packaging and modeling, 2011; Mixed-signal and power-integration packaging solutions, 2010), such as inverters for motor drives and converters for power processing equipment. Integration in power electronics is a rather complex process due to incompatibility of materials and processing methods used in fabrication, and due to the high electrical density levels and electrical isolation requirements these components must handle. Packaging involves the solution of electrical, mechanical, and thermal problems. Electrical isolation is one of the important factors to be considered in the power packaging design, as it relates directly to the product reliability and safety. Based on the standard of International Electrotechnical Commission (IEC) and the US Standard (UL), such as the standard IEC60950-1 (Information technology equipment-safety, part 1: general requirements, 2005) and UL60950-1 (Information technology equipment-safety, part 1: general requirements, 2007), designers shall take into account not only the normal operating conditions of the equipment but also likely fault conditions, consequential faults, foreseeable misuse, and external influences such as temperature, altitude, pollution, moisture, overvoltages in a system that use the power packaging products. This chapter discusses the power package electrical isolation design considerations.