Friction is mostly unwanted in rotating machines. In order to reduce its impact on the system, the integration of magnetic bearings is frequently regarded as a valid solution. In rotating systems like flywheel energy storage systems (FESS), mechanical losses created by mechanical bearings greatly reduce the overall performance. Magnetic bearings are thus frequently integrated in FESS to elimina...

Self-sensing magnetic bearings work without position sensors. The position measurement, which is required by the controller, can be deduced from the electromagnetic interaction between stator and rotor. The self-sensing method discussed in this paper is based on controlling the voltage over the coils and measuring the current through the coils. This method can be realized with a minimal amount ...

Abstract--Control theory gives very few examples of control systems for which the closed-form solution to the LinearQuadratic (LQ) optimization problem exists. This paper describes two such systems of 2nd and 4th order concerning magnetic bearings and gives the closed-form solutions to the LQ-problems. The controller obtained provides the LQoptimal bearing forces and minimizes copper losses in ...

Abstract— The nature of active magnetic bearings has many advantages over the conventional bearing, as its operation is energy efficient and potentially leads to cleaner and noise-free environment. However, the successful operation of an active magnetic bearing system requires a complex real-time control system, because of its unstable characteristics, as well as its nature of being a multi-inp...

We study control problems in magnetic bearing systems that are subject to both input and state constraints. Apart from the usual restrictions on voltages and currents in the circuit systems, most magnetic bearing systems are subject to a severe state constraint: the motion of the rotor (the suspended object) is only allowed in an extremely small airgap, otherwise the collision of the rotor and ...

Magnetic bearings continue to be successfully applied throughout industry. As the population of machines using magnetic bearings grows, so does the interest in the appropriate predictive and preventive maintenance (PPM) procedures necessary to deal with both initial startup and aging related problems. This paper highlights several examples of actual field problems, discusses critical maintenanc...

Introduction: Photothermal therapy (PTT) is a nanotechnology-assisted cancer hyperthermia approach in which the interaction between laser light and plasmonic nanoparticles generates a localized heating for thermoablation of the tumor. Recent efforts in the area of PTT follow two important aims: (i) exploitation of targeting strategies for preferential accumulation of plasmonic ...