Beschreibung
The transition to electric mobility requires the original equipment manufacturer to revise the acoustic behaviour of their vehicles. Noise from other machines, e.g. window lifters, can now be heard inside the car because there is no combustion engine any more that covers these noises. Solving these problems can be very expensive, e.g. installing loudspeakers and damping material. A more efficient way to cancel unwanted noise is the technology of Active Noise Cancellation (ANC) with electric drives. These functions enable electric machines to reduce disturbing sound only with a few more cheap sensors installed and a few more lines of code in the field oriented control software of the electric control unit. Since electric drives are not ideal sound sources, additional harmonics arise when the machine is excited by a specific frequency. This work provides approaches for analysing, modelling and compensating the non-linear effects of a permanent magnet synchronous machine that lead to these harmonics. Firstly some apparent non-linear effects are analysed and the identification methods, e.g. for flux maps, for the corresponding parameters are stated. In the end the so called extended high frequency model for modelling the harmonics is chosen. With the help of this model a compensation scheme is developed which should reduce the arising harmonics. Therefore it is decided to linearise the non-linear system with the help of input/output linearisation for which the extended high frequency model is used. Also a proportional resonant controller is developed. Finally the effect of the currents in the machine especially on forces and sound quantities is evaluated. Therefore a test bench is constructed according to the blocked force method and the compensation scheme is tested.