This paper investigates the effectiveness of sensorless operation in carrier-signal-injection-based sensorless-control methods for permanent-magnet brushless ac motors. The safety area (SSOA) is introduced with due account quantization error analog to digital conversion. SSOA defines a working <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> - xmlns:xlink="http://www.w3.org/1999/xlink">q</i> plane which motor can operate mode guaranteed...

The modulation of TiO2 structure can effectively alter the oxidation kinetics and pathway sacrificial ethanol during water-splitting reaction dramatically adjust selectivity valuable coupling product 2,3-butanediol from 0.0% to 96.6%, showing possibility photohydrogen production in green economical indexes.

In this article, an adaptive linear neuron based current harmonics suppression method for permanent magnet synchronous motors with nonsinusoidal back electromotive force (EMF) is presented, due account dead-time effect. The can be well-suppressed by feedforwarding a self-tuning compensation voltage. proposed does not rely on the knowledge of back-EMF harmonic components and Moreover, easy to implement, since it need process extract harmonics. effectiveness verified both simulation...

This paper overviews high-speed permanent magnet (HSPM) machines, accounting for stator structures, winding configurations, rotor constructions, and parasitic effects. Firstly, single-phase three-phase PM machines are introduced applications. Secondly, HSPM applications, advantages, disadvantages of slotted/slotless non-overlapping/overlapping different i.e., interior (IPM), surface-mounted (SPM), solid PM, summarised in detail. Thirdly, effects due to operation presented, including various...

In conventional rotating carrier signal injection-based sensorless method, a positive-sequence current has no use, and only the negative-sequence is used to estimate rotor position information. The inverter nonlinearity effects, however, distort result in inaccurate estimation. With aid of theoretical analysis experimental measurement, it proven this paper that distortion resulting from effects can be compensate influence on current. Hence, new online postcompensation scheme developed by...

In sensorless control of permanent-magnet brushless ac machines, it is necessary to identify the initial rotor position prior start-up machine. Although saliency-tracking-based techniques are proven be a good candidate estimate in control, magnetic polarity identification another important issue. Since machine saliency undergoes two cycles single electrical period, estimated information based on has an angle ambiguity π. With aid saturation effect, this paper proposes robust estimation...

A novel asymmetric interior permanent magnet (AIPM) machine is proposed in this paper for electric vehicle application. It has a skewed V-shape (PM) cavity, two PMs with different dimensions and an additional flux barrier outside the cavity each pole. This rotor topology can inherently utilize magnetic-field-shifting (MFS) effect to reduce current angle difference between maximum PM reluctance torque components, thereby enhancing synthetic same usage. The influences of positions AIPM...

This article proposes a novel spoke-type asymmetric interior permanent magnet (AIPM) rotor topology that employs an additional flux barrier in each pole of (IPM) synchronous machines for torque density enhancement and pulsating suppression without introducing any extra cost. The proposed AIPM-I machine, existing AIPM-II machine with profile, conventional IPM are designed optimized the same 12-slot/8-pole stator nonoverlapping windings as well diameter PM dimensions. effect dimensions on is...

This article proposes a novel asymmetric interior permanent magnet (AIPM) rotor topology that has mixed V-shape and spoke-type PM configuration, designated as 1.5-layer structure, arrangement of PMs flux barriers. The AIPM is employed for IPM synchronous machines to utilize the magnetic-field-shifting (MFS) effect increasing average torque by reducing current angle difference between peak reluctance components. Three machines, i.e., proposed AIPM, symmetrical IPM-I, conventional benchmark...

The commutation errors undermine the control performance of a brushless direct current (BLdc) drive especially at high-speed operation. In this article, novel error compensation strategy for BLdc that eliminates phase deviation between and back electromotive force is proposed. d-axis introduced used as criterion to determine errors. Since currents contain large amounts harmonics, which makes hard detect, least-mean-square-algorithm-based adaptive linear neuron filter optimal advance angle...

This article investigates the virtual third harmonic back electromotive force (EMF)-based sensorless drive method for high-speed brushless dc (BLDC) motors. Conventional zero-crossing point (ZCP) detection methods of EMF require hardware low-pass filters and voltage comparators, causing serious phase lag. To avoid undesired lag hardware, proposed employs algorithmic oversampling technique to reconstruct envelope EMF. Besides, number sampling points is dynamically adjusted according...

This paper investigates the influence of static and dynamic rotor eccentricities on electromagnetic performance, including air-gap flux density, back electromotive force (EMF), torque, cogging unbalanced magnetic (UMF), a 2-pole/3-slot permanent magnet (PM) motor considering eccentricity ratio, angle, initial angle. Both finite element analyses experiments show that in PM motor, leads to magnitudes phase angles fundamental back-EMFs three phases but does not change harmonic contents, while...

In the high-speed brushless dc drives, long commutation freewheeling duration will increase difficulty of sensorless operation that is based on back electromotive force (EMF) zero-crossing detection. extreme cases when angle exceeds 30°, zero crossing EMF be undetectable, resulting in failure drives. As a result, safety area (SOA) limited by issue. this article, it found pulsewidth modulation (PWM) patterns have big influence angle. Hence, first place, through analytical methods, mechanism...

In order to facilitate the selection of machine whether it is suitable for high-frequency (HF)-signal injection-based sensorless control or not, this paper proposes a complete experimental investigation method analysis and validation saliency level, including primary saliency, which essential HF control, secondary will deteriorate rotor-position estimation. The results obtained on new type switched-flux permanent-magnet (SFPM) prove that with identified accurate estimation can be achieved,...

For high-speed brushless DC (BLDC) drives, the switching-to-fundamental frequency ratio is usually insufficient. As a result, commutation errors caused by PWM switching delay are significant, which means power switches will take action at inaccurate instants. This cause low-frequency current oscillations and produce additional losses. In addition, conventional method accumulative in sensorless operation further lead to instability issues region. order suppress these influences, novel...

This article investigates the influence of stator slot number on electromagnetic performance two-pole high speed permanent magnet (HSPM) slotted motors with toroidal (TO) windings. Four different numbers, i.e., 3, 6, 9, and 12, are globally optimised for maximum torque, their compared, including winding factor, air-gap flux density, back electromotive force, cogging inductances, unbalanced magnetic force (UMF), various loss components. It shows that six-slot/two-pole HSPM motor TO windings...

Although the inverter nonlinearity is caused by several different factors, deadtime and parasitic capacitance effects are major contributors to carrier signal distortion in injection-based sensorless techniques. According experiments, this paper establishes disturbance voltage model of for injection techniques, which comprises both fundamental high-frequency components. With help such model, a new compensation scheme based on positive sequence current developed. Finally, experimental results...

High-speed brushless dc (BLDC) drives usually operate with low carrier-fundamental frequency ratio, which causes abundant sideband harmonic current components. Some harmonics will be induced in low-frequency range, leading to oscillations and torque ripples. To minimize these undesired harmonics, a novel pulsewidth modulation commutation pattern, i.e., carrier-synchronized (CSC), is proposed this article. For comparison, two conventional patterns, including regular-sampled (RSC),...

In this article, three 6-slot/2-pole high-speed permanent magnet motors with 1, 2, and 3 coil-pitch windings are optimized by the finite element method taking into account stator copper loss iron loss. Their electromagnetic performances analyzed compared, including air-gap flux density, back force, torque, winding inductances, various components. For application, compared 1 windings, proposed 2 have a good tradeoff between factor end-winding axial length which attractive for improved torque...

This article proposes a novel asymmetric interior permanent magnet (AIPM) rotor topology for torque enhancement and ripple reduction in IPM synchronous machines. The AIPM structure is featured by hybrid-layer configuration, i.e., each pole, part of PM configuration has one-layer while the other two layers. It allows magnetic-field-shifting (MFS) effect to be utilized reducing current angle difference between maximum reluctance components, thereby effectively increasing resultant torque....