In this paper, we propose a novel structure of permanent-magnet-biased axial hybrid magnetic bearing. It has four segments poles to control three degrees freedom (3-DOF). Based on the inner and outer air gaps in conventional bearings, gap, called subsidiary is constructed between permanent magnet stator poles. This gap separates bias flux paths from paths. As result, lower power loss bearing can be achieved due reluctance Furthermore, by means equivalent circuit method 3-D finite-element...

The 3-degrees of freedom magnetic bearing (3-DOF MB) with permanent-magnet (PM) biased has been applied to high-speed motor progressively for their advantages small thrust disk, low wind friction loss, and volume. To predict performance guide design the 3-DOF MB, an accurate analytical model including eddy-current effects leakage is proposed. Both solid laminated cores are in therefore different core materials modeled separately. frequency response characteristics axial radial stiffnesses...

The rotating machinery suspended by an active magnetic bearing (AMB) system always suffers from rotor mass imbalance and sensor runout disturbances, which lead to the periodic fluctuations in control currents. This paper presents a novel multiple resonant controllers (MRC) for AMB suppress multifrequency current harmonics presence of variable rating speed. principle structure plug-in MRC used suppression is discussed. design proposed MRC, using progressively tuning segmentation switch...

We propose a new structure for permanent-magnet-biased axial hybrid magnetic bearing. Starting with the inner air gap and outer of conventional bearings, we first construct novel between permanent magnet housing, which call second gap, separating bias flux paths from control paths. As result, will have lower reluctance, power loss bearing be lower. Next, modeled this analyzed it using equivalent circuit method, 2-D finite element method (FEM), 3-D FEM. designed assembled an prototype...

To provide a more reliable and low power consumption rotor support system for high-speed compressor, novel compact magnetic bearing damping is proposed. It composed of cup-shaped rotor, an axial passive reluctance type outside the cup, damper with Halbach magnet array inside which not only can adequate stiffness, but also good ability rotor. enhance load stability system, analytical model, calculate stiffness coefficient significantly less computing time than finite element method (FEM),...

In this paper, a novel structure of four degrees freedom (4-DOF) hybrid magnetic bearing is proposed for double gimbal magnetically suspended control momentum gyro (DGMSCMG). It includes two active parts and one passive part, every part has eight stator poles around the circumference in X Y directions, which are divided into upper lower layers. The whole rings, located middle 4-DOF bearing. radial force analyzed by equivalent circuit method (EMCM) axial resilience infinitesimal based on end...

Abstract Background magnetic field compensation can effectively improve the signalto-noise ratio of biomagnetic measurements. But for complex environmental disturbances, creating a stable near-zero environment is challenging topic. Therefore, this paper constructs background system based on Improved Linear Expanded State Observer (ILESO), which reduces fluctuations. Firstly, model obtained input and output characteristics system. Then, an improved linear extended state observer designed to...

Abstract The inverse Preisach hysteresis model plays an important role in simulating the characteristics of magnetic materials and calculating their losses. Uniformly Distributed Centered Cycle (UDCC) method is commonly used to determine distribution function model, but its accuracy low when at densities. This paper proposes accurate fitting parameters using Gaussian mixture (GMM) with non-uniform grid partition. includes two innovative works: first, a hybrid sensitivity associated curvature...

To effectively suppress the synchronous vibration torques for a magnetically suspended rotor (MSR) with significant gyroscopic effects and serious coupling dynamics, novel cross-feedback notch filter is proposed in this paper. First, coupled multi-input-multi-output active magnetic bearing system converted into an equivalent complex single-input single-output (SISO) system. The transformation aims at easing controller design extending classical stability criterion to coefficient frequency...

Objective. Optically pumped magnetometers (OPMs) are recently developed magnetocardiography (MCG) sensors that can detect cardiac diseases. This is of great clinical significance for detecting acute myocardial infarction (AMI) and premature ventricular contractions (PVC). study investigates the use an array OPMs to heart disease in animals.Approach.An was used MCG AMI PVC dogs. We four dogs this study, models with different degrees severity were established by ligating middle proximal...

Abstract Magnetic shielded cylinder (MSC) is crucial in various applications, especially the realm of medical weak magnetic signal measurement. However, designing a small volume, low noise MSC multi-objective optimization problem, with objectives conflict each other. To address complexity arising from numerous variables optimal design volume and low-noise, this paper proposes an method based on non-dominated sorting genetic algorithm II (NSGA-II) to realize high shielding factor, low-noise....

Cobalt-based amorphous alloys (Co-MG) demonstrate ultra-high permeability and remarkably-low power loss, positioning them as promising candidates for shielding (near-) static magnetic fields addressing accuracy limitations in extremely-weak measurements. However, the brittleness poor understanding about performance below 100 Hz have impeded their widespread adoption. To integrate satisfied processing, mechanical performances, polystyrene-grafted Co-MG composites are developed. Compared with...

For existing heteropolar permanent magnet (PM) biased radial magnetic bearing, circuits in X and Y channels are coupled with each other, which makes it more difficult to design the control system influence precision of whole system. A new PM bearing is proposed this paper. The presented independent decreases field coupling two significantly. First, structure working principle demonstrated. Then, analytical formulas for calculating force deduced using equivalent circuit method virtual...

Many magnetically suspended compressors operate above the first bending critical speed, which gives rise to high vibration problems and introduces complications in designing controllers for radial magnetic bearings; besides, a significant axial load always exists high-speed compressors, requires capacity thrust bearings bearings. In this paper, passive damper with Halbach magnet array is proposed. The can provide damping force without control system, also large reduce burden of bearing....