An analysis of noise reduction in variable reluctance motors using pulse position randomization.
Smoot, Melissa C.
Kassakian, John G.
MetadataShow full item record
The design and implementation of a control system to introduce randomization into the control of a variable reluctance motor (VRM) is presented. The goal is to reduce noise generated by radial vibrations of the stator. Motor phase commutation angles are dithered by 1 or 2 mechanical degrees to investigate the effect of randomization on acoustic noise. VRM commutation points are varied using a uniform probability density function and a 4 state Markov chain among other methods. The theory of VRM and inverter operation and a derivation of the major source of acoustic noise are developed. The experimental results show the effects of randomization. Uniform dithering and Markov chain dithering both tend to spread the noise spectrum, reducing peak noise components. No clear evidence is found to determine which is the optimum randomization scheme. The benefit of commutation angle randomization in reducing VRM loudness as perceived by humans is found to be questionable.
Showing items related by title, author, creator and subject.
Practical applicability of exact and approximate forms of the randomization test for two independent samples. Hesse, Derek H. (1987-09);The practical applicability of randomization tests is discussed. The randomization test for two independent samples is the specific test examined in both hypothesis and significance testing contexts. This test has optimum ...
Keener, Lawrence (Monterey, California: Naval Postgraduate School, 2015-12);We consider a recently proposed information disclosure vulnerability called blind return-oriented programming (BROP). Under certain conditions, this attack allows a return-oriented programming attack against previously ...
Design of software package for incorporation of random load testing and data processing on materials testing system machine Blakely, Frederick Martin (Monterey, California. Naval Postgraduate School, 1978-06);This thesis describes the software design and implementation of a microprocessor- based, random load drive and data acquisition system on a Material Testing System (MTS) machine. A microprocessor, combination analog ...