To improve the performance of surface permanent magnet synchronous motor drives, a sensorless control scheme based on sliding-mode observer with an orthogonal phase-locked loop (PLL) incorporating two frequency-extract filters (SFFs) is proposed. The rotor position estimation errors are analyzed. analysis results show that harmonic estimated signal hard to eliminate completely. Therefore, improved adaptive notch filter - SFF proposed extract fundamental wave before applying PLL. This method...

This paper explores a robust μ-synthesis control scheme for structural resonance vibration suppression of high-speed rotor systems supported by active magnetic bearings (AMBs) in the magnetically suspended double-gimbal moment gyro (MSDGCMG). The derivation nominal linearized model about an operating point was presented. Sine sweep test conducted on each component AMB system to obtain parameter variations and high-frequency unmodeled dynamics, including modes. A fictitious uncertainty block...

This paper explores a composite hierarchical antidisturbance control (CHADC) scheme for the resonance vibration suppression of high-speed rotor system supported by active magnetic bearings (AMBs) in magnetically suspended double-gimbal moment gyroscope (MSDGCMG). The dynamics with fictitious integral term is introduced to meet steady-state performance requirements. Resonance disturbances caused harmonic drive transmission and gyroscopic torque gimbal motions are also analyzed. augmented AMB...

A sensorless control method for a high-speed brushless DC motor based on the line-to-line back electromotive force (back EMF) is proposed in this paper. In order to obtain commutation signals, voltages are obtained by low-pass filters. However, due filters, wide speed range, and other factors, actual signals significantly delayed more than 90 electrical degrees which limits acceleration of motor. novel algorithm hysteresis transition between "90-α" "150-α" introduced handle severe retarding...

This paper presents a novel self-correction method of commutation point for high-speed sensorless brushless dc motors with low inductance and nonideal back electromotive force (EMF) in order to achieve steady-state loss magnetically suspended control moment gyro. The before correction is obtained by detecting the phase EMF zero-crossing then delaying 30 electrical degrees. Since speed variation small between adjacent points, difference nonenergized phase's terminal voltage beginning end...

Synchronous vibration is an obstacle to the performance improvement of a rotating shaft supported by active magnetic bearings (AMBs). This paper explores novel autobalancing method for magnetically suspended rotor in motor driveline system based on synchronous frame (SRF) transformation. The principle and structure SRF transformation used online identification physical characteristics imbalance given. A modeling analysis transformation, using complex transfer functions, presented....

In this paper, the design and development of a magnetic bearing system which consists passive axial/tilting active two-axial radial (RMB) used in magnetically suspended wheel (MSW) or control moment gyroscope (MSCMG) for agile satellite application is presented. The supplies an axial position stiffness to stabilize rotor direction tilting restrain when subjected gyroscopic torque. two-axis with bias permanent magnet stabilizes on axes perpendicular rotation axis. Considering complex...

The vibration controllability is an important feature in the applications of active magnetic bearings (AMBs). This paper addresses two key challenges on balancing control AMB-rotor systems: presenting a parallel-mode scheme to enhance notch performance at high speeds, and proposing phase-shift filter ensure stable operations over entire speed ranges. First, both frequency characteristics simplified series parallel mode are discussed. analysis shows that closed-loop system with has deeper...

In order to improve the performance of high-speed brushless direct current motor drives, a novel high-precision sensorless drive has been developed. It is well known that inevitable voltage pulses, which are generated during commutation periods, will impact rotor position detecting accuracy, and further overall drive, especially in higher speed range or under heavier load conditions. For this reason, active compensation method based on virtual third harmonic back electromotive force...

Active magnetic bearing (AMB) levitated rotating machineries are always required to operate above the rotor first bending critical speed achieve a high power density. It is important ensure safe run-down through speeds. This paper presents an optimization of damping compensation for flexible make maximal use limited electromagnetic force retain deformation. The design, modal properties, and model test AMB rig which typifies 10-kW centrifugal compressor described in detail. optimal phase...

In order to improve the performance of surface permanent magnet synchronous motor drives, a novel sensorless drive scheme is proposed in this paper, which based on virtual third-harmonic back EMF incorporating fractional-N phase-locked loop (FN-PLL) and frequency-extract filter (SFF). A simple low-pass circuit used obtain commutation points through EMF. After that, an FN-PLL applied continuous rotor position angles. On basis, SFF-based compensation compensate detecting error adaptively....

Coupling torque, nonlinear friction, and unmodeled dynamics are the main constraints that influence angular speed precision of gimbal systems in double control moment gyros (DGCMGs). This paper explores a novel tracking method based on cascade extended state observer (CESO). The coupling considered as system's lumped disturbance, which is estimated by designed CESO. By introducing feedback controller, disturbances can be eliminated from output channel system. Both simulation experimental...

Thermal analysis calculation is an indispensable checking process in the design of high-speed permanent magnet synchronous machine (HSPMSM) with active magnetic bearings, due to its high loss density and non-contact support mode. The finite element method (FEM) applied for visual global temperature distribution. Because thermal a complex problem reflected interaction among electromagnetic field, fluid so it cannot be solved independently, multi-physical field simulation based on...

Direct air capture (DAC) of CO2 is emerging as an important technology to mitigate the environmental challenges posed by excessive carbon emissions. The development reliable and affordable adsorbents has long been a topic great interest in DAC field. In this work, through quaternization process, inexpensive readily available plant-based biochars including walnut shell, cornstalk, rice husk, long-stalked lentil shell were prepared moisture-swing from ambient air. Among these biochar...

This paper explores the attitude-sensing function of magnetically suspended double-gimbal control moment gyroscope (MSDGCMG), which can combine attitude sensing and into a single device to achieve compact lightweight spacecraft design. In this implementation, two-axis angular velocity is sensed from signals in active-magnetic-bearing system for high-speed rotor. Both current- displacement-force terms are considered proposed scheme order good tracking performance estimation. Furthermore,...

A successful application of the single-gimbal magnetically suspended control moment gyro (SGMSCMG) requires careful attention not only to electromagnetic design and feedback aspects magnetic bearing (MB) but also decoupling between high-speed MB rotor system low-speed gimbal servo system. The key parts with low loss a large-scale SGMSCMG for large spacecraft are proposed. low-loss MBs that consist thrust radial active PM bias proposed (MSCMG) when considering torque. Finally, test results...

The power consumption of actuators is an important concern for the spacecraft attitude control system. This paper presents a reduction method permanent magnet biased active magnetic bearings (AMBs) during torque output moment gyros (CMGs). For simplicity analysis, simple single degree-of-freedom (DOF) AMB system undergoing external load force first presented. An operating point adaptive regulation based on current-integral feedforward proposed to realize coil current with reference position...

For space application, weight and power consumption are the key parameters of an actuator for attitude control spacecraft. In this paper, weight-reduction design based on a novel combined radial-axial magnetic bearing (CRAMB) in large-scale magnetically suspended moment gyro (MSCMG) station application is proposed. The CRAMB consists radial (RMB) unit axial (AMB) unit. Two CRAMBs can 5-degrees freedom highspeed rotor. According to requirement large MSCMG station, with permanent magnet bias...

For a magnetically suspended control moment gyroscope with strong gyroscopic effects, the whirl mode (nutation and precession) stability of active magnetic bearing (AMB) rotor system has always been challenging problem. This article proposes robust method combined regional pole assignment to achieve in AMB-rotor system. First, physical model multi-degree-of-freedom is analyzed detail, state-space established. Then, effects varying speed are considered as bounded parameter perturbation...

With the advantages of a high power-to-weight ratio and oil-free bearings, magnetically suspension centrifugal compressor (MSCC) equipped with active magnetic bearings operates more efficiently than traditional mechanical compressors over wide speed range by precisely controlling high-speed permanent-magnet synchronous motor (PMSM). However, owing to harsh working environment, parameters, including resistor, inductance, flux linkage, vary significantly. This degrades rotor position observer...