Design of Low-Noise Switched Reluctance Drives

In summary, this thesis provides tools and methods to analyze and investigate acoustic noise and vibration in SRMs to optimize the design for low-noise. Chapter 2 begins with a short overview of the design goals, constraints as well as design tools and methods. Chapter 3 summarizes the basic signal theory and introduces some mathematical methods needed to address the acoustic noise issue in general in chapter 5. This includes also a review on different methods of sound assessment in chapter 4. Afterwards, the presented theory is applied to switched reluctance machines in chapter 6 before deriving and presenting different methods of noise and vibration simulation in chapter 7. Simulation results are verified and compared to experiments performed on various SRMs, including 2 kW 35,000 rpm vacuum cleaner drives with different one- and two-phase machine configurations (6/6, 4/2, 8/4), 4-phase 8/6 drives for weaving machines (11 kW main drive and 2.7 kW auxiliary drive), a 4-phase 16/12 50 kW and a 3-phase 18/12 17 kW drive for electric vehicles. Control as well as design options to mitigate acoustic noise in SRMs are presented in chapter 8.