Behavioural models for common mode EMI filters

Abstract

EMC is defined as the “ability of an equipment or system to function satisfactorily in its electromagnetic environment without producing intolerable electromagnetic disturbances to anything in that environment”. EMC means that equipment shall be designed and manufactured, in such way that: - The electromagnetic disturbance generated does not exceed the level above which radio and telecommunication equipment or other equipment cannot operate as intended. - It has a level of immunity to the electromagnetic disturbance to be expected in its environment which allows it to operate without unacceptable degradation of its indented use. Electric motors convert electrical power into mechanical power within a motor‐driven system. Electric motors and the systems they drive are the single largest electrical energy consumer, more than twice as much as lighting, the next largest energy consumer, and represent close to 70% of the electrical energy consumption in the industrial sector worldwide [1]. One of the major problems faced by motor drives is Electromagnetic Interference (EMI) which produces unwanted effects on surrounding electronic devices. A traditional way to control EMI in motor drives is the introduction of EMI filters. However a successful and first-time-right design is a ‘done thing’ only to a few experienced designers. The filter though is often not optimized in terms of weight, cost and EMI reduction abilities. Enhancing these performance criteria and supporting a first-time-design at the early stages of development, are the objectives of the work presented in this thesis.