EMC design considerations for medium to large variable speed drives in industry

Over the last two decades, the number and variety of process control applications with variable speed motor drives (VSDs) in the range of hundreds of kW´s up to MW´s have permanently expanded. This paper provides an overview of the main Electro Magnetic Interference (EMI) issues encountered with these drives in industrial applications, the corresponding EMC solutions and their theoretical background. The content is based on numerous EMI incidents and troubleshooting measurements in production facilities for oil and gas, chemicals, food processing as well as paper and steel mills.