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This project is directed at the third generation of heart pumps being developed in commercial research laboratories which employ feedback-controlled magnetically levitated pump impellers. Unique features of the control problem are the quasi-periodic pressure disturbances of the natural heart and nonlinearities of the magnetic levitation system. The main motivation for this paper is the power consumption due to quasi-periodic pressure disturbances from the natural heart. Since clinical studies are not possible for the vast majority of our work, there is a need for an apparatus to simulate the Left Ventricular Assist Device (LVAD) for controller design. Inspired by this need, we design a novel experimental apparatus to study the Maglev LVADs. We develop a nonlinear model, then a linearized model followed by simulation and stabilization of the closed loop system using a Virtual Zero Power (VZP) controller.

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In this paper we consider a simple model for systems with friction. The model includes differential equations with discontinuous right-hand side. We prove the existence and uniqueness of solution, and also discuss performance limitations caused by friction associated with tracking limitations.

This paper presents a novel simulator for hard disk drive (HDD) spindle motor, developed to accelerate motor design verification for large volume product by predicting spin-up time (a performance metric) and voltage headroom (an important reliability metric). The simulator comprises of a BLDC (brushless DC) spindle motor model, firmware block, and power device block. The simulator integrates physics-based model structures with more complex measurement-based behavioral aspects at various temperatures and speeds. All model parameters incorporate realistic environmental factors and part variations; simulation of large sample size of in silico drive design based on Monte Carlo (MC) selection of parameters yields theoretical results capable of predicting defective parts per million in field. The simulator uses a modular approach allowing changing of firmware settings, details of Power Large Scale Integration (PLSI), and motor mechanics, which are product specific. This simulator model can be used for feasibility assessment of new electromechanical designs, available design margins for motor selection and it is also a reliable tool to provide boundaries for firmware (FW) settings to avoid reaching failure modes.