Permanent Magnet Rings Research Articles

Analysis of extrusion characterization of Nd-Fe-B permanent magnet ring based on Normalized Cockcroft & Latham fracture criterion

The hot deformation behavior of hot-pressed Nd-Fe-B material was investigated using a Gleeble-3500 thermal simulation machine, with deformation of 50 %, temperatures ranging from 700 to 850 °C, and strain rates ranging from 0.01 to 1 s−1. A hyperbolic sine model was employed to establish a constitutive equation suitable for this material. In addition, the chosen fracture criterion and damage threshold in the simulations were validated against the experimental results. Then, a three-dimensional thermo-mechanical coupled model was developed to simulate the damage evolution of the material during the extrusion process. The effects of different extrusion processes and positions of the back pressure tool on the magnetic performance and forming quality of the material were investigated. The simulation results indicate that both the combined extrusion process and the back pressure tool located at the half of the workpiece will contribute to improve the uniformity of the magnetic properties, and effectively ensuring the regularity of the forming process at the top of the magnetic ring and suppressing the occurrence of cracks. The results of this paper will help to a better understanding of the deformation mechanism of Nd-Fe-B permanent magnet and provide a valuable theoretical guidance for the preparation of high-performance Nd-Fe-B magnetic rings.

Analysis of a passive vibration damper for high-speed superconducting magnetic bearings

Superconducting magnetic bearings (SMB) based on a combination of high temperature superconductors and permanent magnets enable the realization of self-stabilized high-speed devices with significantly reduced friction. However, external vibration might couple in the bearing resulting in large amplitude oscillations due to a resonance case. A dedicated eddy current damper (ECD) might be used to eliminate these oscillations for a stable operation. The influence of such damping elements was studied for a frictionless SMB twisting system designed to speed up the conventional ring spinning process. Therefore, conductive copper rings with different thicknesses were implemented at different positions into the bearing setup as ECD. Afterward, the SMB setup was analyzed during acceleration using an array of laser distance sensors to record the displacement of the levitating permanent magnet ring in radial and axial direction, respectively. Simultaneously, a numerical model was developed to investigate the influence of the ECDs on the dynamic and static behavior of the SMB in more detail. It was shown that the simulated damping coefficients are in good agreement with the measured values, which allows further optimization of the ECD with the developed numerical model.

Axial Stiffness Augmentation by Adding Superconductor Bulks or Limiting Permanent Magnet Rings to a Horizontal Axis Zero-Field Cooled High-Tc Radial Passive Superconducting Bearing

This paper analyzes the viability of different solutions to passively augment the axial stiffness of a horizontal axis radial levitation passive magnetic bearing (PMB) with a previously studied topology. The zero-field cooling (ZFC) of high-temperature superconductor (HTS) bulks promotes higher magnetic impulsion and levitation forces and lower electromagnetic losses than those with field-cooling (FC) but, on the other hand, the guiding stability is much lower than those with FC. Because of stability reasons, FC was adopted in most superconducting maglev systems. The trend of this research group has been to develop a horizontal axis HTS ZFC radial levitation PMB presenting notable levitation forces with reduced electromagnetic losses, defined by a topology that creates guiding stability. Previous work has shown that optimizing the bearing geometry to maximize magnetic guidance forces might not be enough to guarantee the axial stiffness required for many applications. First, the extent to which guidance forces are augmented by increasing the number of HTS bulks in the stator is evaluated. Then, the axial stiffness augmentation by passively adding two limiting permanent magnet (PM) rings is evaluated. The results show that the axial stiffness is highly augmented by adding limiting PM rings with no significant additional investment. This change enables the use of the studied ZFC superconducting PMB in high-precision axial stability applications, such as precision gyroscopes, horizontal axis propellers, and turbines.

<i>In Situ</i> Measurement of Twist Propagation and Yarn Tension with Superconducting Magnetic Bearing Twisting Element for Ring Spinning Process

The twisting of yarn in one of the most widely used conventional ring spinning processes is based on the ring/traveler system. The existing limitation of productivity in the ring spinning process lies on the prevailing force relation between ring, traveler and yarn as well as the frictional heat between traveler and ring, principally in the ring traveler system. Recently, a frictional free twisting element based on a superconducting magnetic bearing (SMB) was developed to increase the productivity of ring spinning drastically, which was patented by ITM and Leibniz IFW Dresden. This SMB consists of a circular superconductor and a permanent magnet (PM) ring. In the superconducting state, the PM ring levitates and can freely rotate even up to an angular speed of 50.000 rpm. It is connected with the spindle via the yarn through a guide attached to the PM ring to impart yarn twist. Through the rotation of the PM ring, the twist propagates to the nip point of the delivery rollers. The twist propagation rate depends on different parameters, e.g., spindle speed, balloon geometry, and friction between yarn and yarn guides. A change in the level of twist affects the process, yarn tension, yarn breakage rate, and yarn properties. Hence, it is important to investigate the twist distribution to derive effective measures for improving the twist propagation especially at higher angular spindle speeds and thus eliminate weak points to increase process stability and yarn quality. The aim of these measurements is to analyze the twist distribution along the yarn path to understand the causes of yarn breakages. In this study, the yarn path was traced at different regions by in-situ measuring the helix angle of twisted yarn using a high-speed camera. From the recorded images, the number of twists per unit length was determined using the image processing software ‘Image J’. Thus, the measurement method allows a new insight into the problem of yarn breakages originating from twist propagation in order to take optimized measures at higher angular spindle speeds.

Effect of magnetic field strength on the performance characterization of a low-power wall-less Hall thruster

The wall-less Hall thruster is expected to overcome the issue of wall erosion in miniaturized Hall thrusters. A unique structure of negative gradient magnetic field is used to constrain the plasma behavior. In this paper, permanent magnet rings with different thicknesses were used to adjust the magnetic field strength, and its effect on discharge characteristics and thrust performance was experimentally investigated. The experiment results show that increasing the magnetic field strength can reduce the current oscillation and increase the maximum operating voltage. Within a limited range, increasing the magnetic field strength can significantly improve thrust performance. However, excessive magnetic field strength leads to a decrease in anode efficiency. The optimal magnetic field strength appears at 121 mT, with a thrust of 5.5 mN, a specific impulse of 935 s, a thrust power ratio of 51 mN/kW, and an anode efficiency of 23.1 %. Based on the analysis of different efficiency parameters and plume images, under excessively high magnetic field strength, the shortening of the ionization region may lead to intensified leakage of neutral atoms, which may be the primary reason for the reduction in propellant utilization and anode efficiency.

Analysis of the Magneto-Thermal Bidirectional Coupling Strength of Macro and Micro Integration for Self-Starting Permanent Magnet Hysteresis Synchronous Motors

High-speed permanent magnet synchronous motors (PMSMs) are usually started with the hybrid low-speed open-loop and high-speed closed-loop control mode. However, low-speed open-loop control produces large starting current, or even current overload, resulting in demagnetization and motor damage. Therefore, there is an urgent need to develop a high-speed permanent magnet synchronous motor with self-starting ability at low speed, that is, a permanent magnet hysteresis motor (PMHM). This paper takes the permanent magnet ring hysteresis column rotor structure as the research object. Firstly, the performance of this type of rotor is improved using the micro level of effective layer material AlNiCo, and the mechanical properties of AlNiCo are calculated. Secondly, based on the thick-walled cylinder theory, the analytical model for calculating the strength of the composite rotor considering the temperature effect is deduced, and the tangential and radial stress distribution for each part of the rotor under no-load and load conditions are obtained. Then, the electromagnetic losses and temperature field distribution of the rotor are obtained using the magneto-thermal bidirectional coupling finite element method. Finally, strength of the thermal rotor is analyzed by substituting the temperature rise curve function and AlNiCo parameters at the operating temperature. The comparison of the stress calculation results of the semi-analytical solution and the finite element method showed that the error between both of them is less than 5%, which verified that the semi-analytical solution can accurately analyze the thermal stress distribution of the rotor during high-speed rotation.

Modeling, simulation, and implementation of a superconducting magnetic bearing twisting system in a high‐speed ring spinning process

AbstractThe implementation of a Superconducting Magnetic Bearing (SMB) system is a promising solution for the problem of friction exhibited in the twisting elements of the conventional ring‐spinning process. This research focuses on the development of a dynamical model with six degrees of freedom of the Permanent Magnet (PM) ring used in an SMB system for a high‐speed ring spinning process. The modeling takes into account the magnetic forces and torques that enable the magnetic levitation of the PM ring. Experimental tests allow the identification of unknown parameters of the model and the validation is done through simulations.

Design of a Miniaturized Electron Cyclotron Resonance Ion Source for High-Voltage Proton Accelerator

The Electron Cyclotron Resonance (ECR) ion source fulfills high-current, high-efficiency, and compactness requirements for high-voltage proton accelerators. It is a cathode-free source that uses microwaves to heat a magnetically confined plasma, so there is no cathode loss resulting in a short service life. We finished the design for a miniaturization ECR ion source system, including a microwave system and source body. The traditional microwave system’s scale, which is approximately 1 m, has been reduced to 0.234 m, and the transmission efficiency is greater than 90%. The influence of cavity size and magnetic field distribution on gas ionization is analyzed under the condition that the outer size of the permanent magnet ring is limited, and the optimal scheme of cavity size and saddle-shaped magnetic field distribution is obtained. This design meets the requirement of fitting the ion source system into the restricted space in the high-voltage accelerator’s head.

PEDS13: Systemic force evaluation of Magnetic Bearings Design for a Pediatric LVAD Study

Study: A miniature magnetic levitation bearing system (maglev) was proposed for an implantable pediatric LVAD. The maglev bearing system is comprised passive radial bearings made of permanent magnet (PM) rings, and an active axial bearing. The study evaluates the passive bearing’s ability to radially stabilize the rotor within a moveable range of radial and axial displacements, and characterizes the axial forces produced. Methods: A stacked pair of concentric PM rings was placed on each side of the rotor and stator for the radial bearings. The PM rings were placed with like poles facing each other. The outer PM rings and stator were mounted on a six-axis force sensor attached to an xyz micrometer driven stage to set the position, and a rotational stage for alignment. The rotor and inner PM rings were inserted in the stator and held in place by both ends. The forces produced were measured at a combination of radial (0mm to 0.35mm with 0.05mm steps) and axial (0mm to 0.25mm with 0.05mm steps) displacements away from the center for a combination of 48 points. The measurements were taken three times and the average was taken. A finite element simulation was conducted by combining previously validated models of the motor, and the PM ring bearings to calculate radial and axial displacement forces. Results: As radial displacement increases, bearing force towards the center increases. Axial displacement decreases the force magnitude, but the direction towards the center remains. This shows the bearing’s ability to radially stabilize the rotor at a range of different radial and axial displacement combinations. As you increase axial displacement, the axial force away from the center increases. The radial position has little effect on axial force. This study quantifies the passive bearing’s axial forces to use in future work of developing the active axial bearing. The simulation results are in accordance with the experimental results. Variation is likely due to rotor-stator alignment error, holder manufacturing tolerances, and rotor rod flexing.Figure 1. Experimental Force Test SetupFigure 2. Axial and radial forces produced. Points are experimental results, dashed lines are simulation results.

A Novel Axial High-Temperature Superconducting Magnetic Bearing With Simple Structure and Large Suspension Force

In this paper, we propose a novel axial high temperature superconducting magnetic bearing (HTSMB) which is used in the field of shaftless magnetic levitation flywheel. The permanent magnet (PM) rotor of the HTSMB is assembled with Halbach PM rings and a polymagnet yoke disc, and HTS bulks are equally distributed in a circle on the stator disk. Firstly, the structure of the novel axial HTSMB is proposed, and the potential advantage is introduced. Secondly, the suspension characteristic of a HTS bulk is simulated based on COMSOL Multiphysics interface of Magnetic Field, No Current (mfnc), Magnetic Field Formula (mfh), and Moving Mesh (ale), and it is verified by experiments. On this basis, the specific structure and size of the HTSMB are optimally designed by using ANSYS Maxwell. Then, the HTSMB is processed and assembled, a general method for assembling the PM rotor is introduced in detail. Finally, the suspension characteristic of the HTSMB is experimentally studied. The experimental results show that the HTSMB has more advantages in axial suspension characteristics and material cost.

Research on Magnetic Characteristics and Fuzzy PID Control of Electromagnetic Suspension

This paper proposes an electromagnetic suspension with an electromagnetic actuator, which can improve the riding comfort and stability of the vehicle without changing the safety of traditional MacPherson suspension. First, the electromagnetic suspension structure is introduced, and the principle of the proposed actuator is described in detail. Second, a magnetic flux density model of a single PM ring (permanent magnetic ring) and a magnet assembly are built, and a theoretical analysis of the magnetic flux density is carried out for comparison. Then, the magnetic flux distribution of the magnetic field is simulated and analyzed using the finite element method (FEM), and is compared with theoretical and other experimental data. Finally, a vehicle dynamics model with 7 DOF is built, and vehicle simulations based on the fuzzy PID algorithm are carried out on a C-grade road surface and a deceleration strip. The theoretical results and simulation analyses of the FEM indicate that compared with the MacPherson suspension, the root mean square values of the acceleration of centroid acceleration for the electromagnetic suspension are increased by 59.08% and 33.34%, respectively, on a C-grade road surface and a deceleration strip, and other physical quantities have also been improved. The structure and characteristics of the proposed electromagnetic suspension that improve the riding comfort of the suspension and enhance the stability of the MacPherson suspension are feasible.

A study of a modified design of dumbbell-shaped flux switching tubular linear generator for regular wave energy conversion

Wave energy converters (WEC) use indirect drive hydraulic or turbine-type power take-off (PTO) mechanisms which consist of many moving parts, creating mechanical complexity and increasing the installation and maintenance costs. Linear generator-based direct drive wave energy converters could be a solution to overcome this problem, but the efficiency of the single conventional linear generator is not high enough, and it cannot work satisfactorily in the low-frequency range.In this paper, a novel dumbbell-shaped flux-switching linear generator has been proposed and studied as a power take-off unit for ocean wave energy conversion. The linear generator has a dumbbell-shaped stator, and the design is ameliorated by placing the permanent magnet rings of longitudinally alternating magnetic pole directions in the slots of its stator outer surface and is separated by thin wall steel ring shoulders. The linear generator also has a dumbbell-shaped translator. The stator is hollow where the translator slides inside axially inducing current in the coil. A long permanent magnet is inserted inside the hollow steel dumbbell core of the translator and a copper coil is wound around the outer surface of the moving translator core. The addition of permanent magnets on the outer slots of the stator is found to increase the output power significantly. To facilitate the investigation, the modified generator design has been compared to the conventional linear permanent magnet generator for their performances using the finite element method, as both machines are different in their structures. The results show that the double dumbbell-shaped flux-switching linear generator gives higher power output, magnetic flux density, branch current, and induced voltage. The double dumbbell-shaped flux-switching linear generator is then placed in a cylindrical buoy and investigated in a wave energy converter in the ocean environment. The hydrodynamic response of the cylindrical buoy has been investigated through ANSYS AQWA. The dynamic differential equations of the wave energy converter have been developed and solved for regular waves using Matlab codes. The peak output voltage, power, and the relative displacement of the linear generator translator with respect to the stator fixed with the buoy have been calculated through the Fourier Transform in the frequency domain using a Matlab code and through numerical integrations in the time domain using a Matlab Simulink code. The results in the time and frequency domains are compared and verified with each other. The relative displacement between the translator and stator buoy has been used as motion input of the ANSYS Maxwell simulation model, and the output voltage results of the ANSYS Maxwell simulation model have been compared and verified with those of the Matlab simulation models. The linear generator design in the wave energy converter under the regular wave excitation is further optimized for the maximum ratio of the peak output power to peak cogging force using the central composite design-based response surface method (RSM). The ANOVA analysis is used to validate the response surface model where its R2 coefficient of 99.93% has indicated an excellent fit. The methods and results differ from those presented in previous studies.

Analytical Analysis of a Novel Flux Adjustable Permanent Magnet Eddy Current Coupling with Double-Sided Conductor

The permanent magnet eddy current coupling is widely used in fan and pump equipment as an energy-saving speed control device. The traditional coupling speed adjustment method occupies too much axial space, limiting its application in the process of upgrading old equipment. This paper proposes a novel flux adjustable permanent magnet eddy current coupling with a double-sided conductor to reduce the coupling axial distance while increasing the coupling output torque. The relative angle between the permanent magnet rings is controlled to adjust the output torque, and the double-sided conductor structure is used to improve the output torque. The working principle of the proposed design is illustrated. An analytical model for estimating the regulation performance of the proposed structure is proposed, which introduces the regulated reluctance into the equivalent magnetic circuit method. Based on this model, the expressions for magnetic flux density, eddy current density, and output torque are established. Finally, the accuracy of the analytical model was verified by the 3D finite element method, and the parameter sensitivity analysis was performed. The analysis results show that this device can achieve a relatively large range of output torque regulation under the condition of a fixed air gap, and the output torque is greatly improved by adopting a double-sided conductor structure.

Study on the magnetic self-levitation of the ring permanent magnet with inserted inner cores in ferrofluid

The self-levitation of a magnetized object composed of ring permanent magnet, soft magnetic pure iron core (Fe-core), and nonmagnetic aluminum core (Al-core) in ferrofluid (FF) is studied, and the focus is the influence of Fe-core (Al-core) on the magnetic fluid levitation force (MFLF) received by the immersed magnetized object. The formula for calculating MFLF is derived focusing on the gas–liquid and solid–liquid boundary interface between FF and surroundings, and experiments have been done to study the dependence between MFLF and the levitation height of the magnetized object and mass of FF. Researches show that Fe-core has a significant influence on MFLF, and the influence is determined by the magnetization of Fe-core and the distance between Fe-core and the boundary interface. In a word, the use of Fe-core is beneficial to obtain a smaller MFLF, the greater the magnetization of the Fe-core is and the closer it is to the boundary interface of FF, the smaller the MFLF is. The Fe-core near the bottom surface of the ring magnet tends to reduce the maximum MFLF corresponds to an approximate horizontal gas–liquid boundary interface when the levitation height is constant, and the Fe-core near the top surface of the ring magnet is more likely to reduce the change of MFLF caused by the disappearance of surface instability of FF. Or, in other words, the Fe-core near the top surface of the ring magnet tends to reduce the MFLF when magnetized object moves upward, and vice versa.

Magnetic Soft Helical Manipulators with Local Dipole Interactions for Flexibility and Forces.

Magnetic continuum manipulators (MCMs) are a class of continuum robots that can be actuated without direct contact by an external magnetic field. MCMs operating in confined workspaces, such as those targeting medical applications, require flexible magnetic structures that contain combinations of magnetic components and polymers to navigate long and tortuous paths. In cylindrical MCM designs, a significant trade-off exists between magnetic moment and bending flexibility as the ratio between length and diameter decreases. In this study, we propose a new MCM design framework that enables increasing diameter without compromising on flexibility and magnetic moment. Magnetic soft composite helices constitute bending regions of the MCM and are separated by permanent ring magnets. Local dipole interactions between the permanent magnets can reduce bending stiffness, depending on their size and spacing. For the particular segment geometry presented herein, the local dipole interactions result in a 31% increase in angular deflection of composite helices inside an external magnetic field, compared to helices without local interactions. In addition, we demonstrate fabrication, maneuverability, and example applications of a multisegment MCM in a phantom of the abdominal aorta, such as passing contrast dye and guidewires.

NO2 Sensor Based on Faraday Rotation Spectroscopy Using Ring Array Permanent Magnets.

Faraday rotation spectroscopy (FRS) exploits the magneto-optical effect to achieve highly selective and sensitive detection of paramagnetic molecules. Usually, a solenoid coil is used to provide a longitudinal magnetic field to produce the magneto-optical effect. However, such a method has the disadvantages of excessive power consumption and susceptibility to electromagnetic interference. In the present work, a novel FRS approach based on a combination of a neodymium iron boron permanent magnet ring array and a Herriott multipass absorption cell is proposed. A longitudinal magnetic field was generated by using 14 identical neodymium iron boron permanent magnet rings combined in a non-equidistant form according to their magnetic field's spatial distribution characteristics. The average magnetic field strength within a length of 380 mm was 346 gauss. A quantum cascade laser was used to target the optimum 441 ← 440 Q-branch nitrogen dioxide transition at 1613.25 cm-1 (6.2 μm) with an optical power of 40 mW. Coupling to a Herriott multipass absorption cell, a minimum detection limit of 0.4 ppb was achieved with an integration time of 70 s. The low-power FRS nitrogen dioxide sensor proposed in this work is expected to be developed into a robust field-deployable environment monitoring system.

Магнитная система одноосного инерционного магнитожидкостного акселерометра

Today, a physical problem of engineering design of inertial magnetic fluid accelerometers to measure dynamic processes is relevant. The main drawback of modern sensors is the nonlinear characteristic of the forced response, which limits the application area of the sensors to the case of quasi-static action (tilt angle sensor). The reason of nonlinearity is the design of the magneto-mechanical system of the elastic suspension of the inertial mass made in the form of a pair of permanent ring magnets. This drawback can be eliminated by designing an axisymmetric electromagnetic system that generates a magnetic field with a linear intensity gradient along the symmetry axis. Thus, the paper is devoted to this problem and experimental approvement of the results on a laboratory sensor prototype. The Monte Carlo algorithm is used to calculate electromagnetic system containing permanent magnets and magnetizing coils. The algorithm is implemented using the C++ programming language. Measurements of the most important parameters of the magnetic field from the point of view of the purpose of the study are carried out on the assembled model of the electromagnetic system of the accelerometer. The calculation of electromagnetic system that generate permanent magnetic field with linear intensity gradient along the symmetry axis is carried out. The applicability of the Monte Carlo method to solve similar engineering problems is shown. The measurements of the magnetic field strength of a given configuration have been made. The force of the magnetic field acting on the test sensitive element with a constant magnetic moment is measured. A comparison of the calculated magnetic field with the field of a real system is carried out. It shows satisfactory agreement between the calculated data and the real ones. A linear dependence of the restoring force on the displacement coordinate of a body with a constant magnetic moment from the equilibrium position is shown. The linearization of the response of the mechanical part of the magnetic fluid accelerometer is achieved by choosing the desired configuration of its electromagnetic system, which allows making reliable measurements of both static and dynamic quantities.

Magnetostatic buoyancy force acting on a non-magnetic sphere immersed in a ferrofluid magnetized by a gradient field

A buoyancy force that acts on the solid non-magnetic sphere immersed in a ferrofluid magnetized by a gradient magnetic field is considered in the framework of 5 physical approaches. The paper overviews (i) the effective magnetic moment and (ii) the antimatter hole concepts, (iii) the excess polarization approach (Pohl), and (iv) the Maxwell stress tensor analysis (Naletova). We propose (v) the ponderomotive buoyancy force decomposition developed according to the general Rosensweig formula which distinguishes between volume and surface effects. Our approach shows the physical background of the buoyancy force, gives estimates of the ratio of surface-to-volume forces and allows to calculate the pressure, which deforms (squeezes) the sphere. All analytical formulas were compared and verified by applying direct numerical simulations to the problem of a small non-magnetic sphere immersed in a ferrofluid characterized by the linear magnetization law. The applied gradient field was assumed to be generated by two coaxial permanent ring magnets. It is shown that the proposed formula (v) is equivalent to (iii) (numerical matching), although they differ by a coefficient that equals 1 in case of the non-magnetic sphere. For the magnetic body, these expressions differ quantitatively, because formula (iii) gives the resultant magnetic force, while formula (v) describes only the action of the ferrofluid.

A novel Halbach array electromagnetic pump for liquid metal flow: Design proposal and performance analysis

This paper proposes a “Halbach array electromagnetic pump for liquid metal” (HA-EMP) by applying the “Halbach ring permanent magnet array” to a direct current conductive electromagnetic pump (DC-EMP). Material selection and structure designs are carried out based on the application background of the liquid metal secondary loop in a space reactor. Performance under different flow rates, currents and duct dimensions of the electromagnetic pump are studied. The conclusions are as follows. The magnetohydrodynamic (MHD) braking effect caused by the magnetic field is responsible for the limited flow rate in DC-EMP. Increasing the magnetic flux density in the fluid facilitates a higher pressure head but also a lower flow rate. Comparing with the traditional structure electromagnetic pump (Trad-EMP), HA-EMP possesses more development potential in view of higher pressure head, smaller size and lighter weight. For the same size, the HA-EMP increases static pressure head and work efficiency by more than 84% and 15%, respectively, while the flow rate is reduced by more than 41%, at conditions of the currently studied parameter ranges. When the magnetic flux density is the same, HA-EMP can save more than 50% of volume compared to Trad-EMP. However, the end effect of the magnetic field along the flow still severely hinders its better performance and will become the next focus of optimization.

Frequency Mixing Magnetic Detection Setup Employing Permanent Ring Magnets as a Static Offset Field Source.

Frequency mixing magnetic detection (FMMD) has been explored for its applications in fields of magnetic biosensing, multiplex detection of magnetic nanoparticles (MNP) and the determination of core size distribution of MNP samples. Such applications rely on the application of a static offset magnetic field, which is generated traditionally with an electromagnet. Such a setup requires a current source, as well as passive or active cooling strategies, which directly sets a limitation based on the portability aspect that is desired for point of care (POC) monitoring applications. In this work, a measurement head is introduced that involves the utilization of two ring-shaped permanent magnets to generate a static offset magnetic field. A steel cylinder in the ring bores homogenizes the field. By variation of the distance between the ring magnets and of the thickness of the steel cylinder, the magnitude of the magnetic field at the sample position can be adjusted. Furthermore, the measurement setup is compared to the electromagnet offset module based on measured signals and temperature behavior.