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This research analyzes the vibration phenomenon in certain types of fractional slot permanent magnet synchronous machines that excites low order radial forces. The study utilizes a motor topology from the group having 12-stator slots and 10-rotor poles (12s10p) to identify and propose several design-based solutions to reduce vibration. Some electromagnetic design feature variations in the motor geometry...
The marine industry is seeing an increasing number of vessels equipped with electric propulsion opposed to traditional mechanical propulsion. Electric propulsion has been shown to be advantageous in various land applications such as locomotives and road vehicles however in the marine setting the highly variable hydrodynamic load exposes the electric propulsion system to extreme load conditions. This...
Based on analysis of sources of the noise of switched reluctance motor (SRM), the paper puts forward methods to reduce noise in terms of torque ripple and phase change from the point of control view. In the low speed stage, phase current closed-loop segmented according to the sine and cosine curve, maintain a constant torque to reduce the torque ripple. Put forward soft turn-off method at the time...
In practice, the lift that a propeller produces is composed of theoretical value and fluctuation, which results in vibration in aircraft. This paper will analyze the effect of the fluctuation on the quadcopter. In order to reduce the vibration caused by the fluctuation, an improved Additive-State-Decomposition-Based (ASDB) dynamic inversion stabilized controller is proposed. To show its effectiveness,...
Many high-end power machines demand greater bearing performance in terms of running speed, precision, reliability, longevity, noise reduction, etc. An ultrasonic bearing based on Near-Field Acoustic Levitation (NFAL) effect is a kind of emerging noncontact gas bearing. Due to its self-aligning capability, the ultrasonic bearing can steadily run at a high speed under high precision. Actuated by piezoelectric...
Many high-end power machines demand greater bearing performance in terms of running speed, precision, reliability, longevity, noise reduction, etc. An ultrasonic bearing based on Near-Field Acoustic Levitation (NFAL) effect is a kind of emerging noncontact gas bearing. Due to its self-aligning capability, the ultrasonic bearing can steadily run at a high speed — tens of thousands of revolutions per...
Vibration analysis is one of the most successful techniques used for condition monitoring of rotating machines. Vibration analysis is a very efficient and convenient tool for diagnosing mechanical problems in induction motors. The aim of this paper is to show that vibration analysis is an efficient tool for diagnosing electromagnetic problems in induction motors, which are very specific for this type...
In industrial electrical drives has been traditionally employed the technique of analysis the technique of analysis of vibration to detect misalignment between the motor axes and the load. This technique requires the placements of sensors directly on the drive, which makes it difficult to apply. In some cases, it may be impossible to apply (submerged or hard access drives). Recently, as complement...
Hand tremor is a neurological disorder that affects people with Parkinson's disease and elderly affecting day to day activities. Hand vibration is a rhythmic muscle movement that occurs due to disorder in the motor system of human body. There are no permanent treatment options available. The subjects typically do life style modifications to cope up with the disease. In this work, we propose a wearable...
In 2015, InnaLabs reported on the development of a range of specialist, precision Quartz Pendulous Accelerometers. The performance requirement for these accelerometers was a key design driver for meeting the market needs within the tactical and the navigation grade market segments. In order to extend InnaLabs offering to cutting edge, volume applications with more stringent and highly dynamic environments...
In order to reduce noise and vibration in switched reluctance motors (SRM), many kinds of commutation methods have been proposed. One of them is well-known as 2-stage commutation method. However, it has a defect which is revealed particularly when SRM is operated at high speed and high load condition. In this study, through the magnetic-structural coupled analysis using FEM and the mathematical analysis...
This research analyzes two stator design features as structural solutions to reduce noise and vibration in permanent magnet synchronous machines (PMSM). The study was focused on a surface mounted PMSM with 12-stator slots and 10-rotor poles where vibration is a well-known issue. The structural-harmonic analysis was used to quantify the vibration by analyzing the radial deformation and acceleration...
Condition monitoring of electric machines is a procedure of increasing importance, as fault tolerant systems are becoming mandatory in many applications. Early diagnosis of faults is a basic pillar in order to achieve full tolerance by the maintenance of faulty parts in electrical machines. As far as electrical drives are concerned, the share of mechanical faults (imbalances, gears and bearings) is...
In order to improve the output performance, multi-stator structure is applied to traveling wave type ultrasonic motor (TWUM). In this paper, taking into account the multi-stator traveling wave type ultrasonic motor (MSUM) with diameter of 60mm, authors apply the elastic contact principle to deduce the MSUM's simulation model. By reason of machining errors and installation errors, the stators and rotors...
The article presents simulation research concerning speed control of two mass system with elastic joint and backlash utilizing the ADRC method. The model of the plant and the structure of the ADRC speed controller are presented together with mathematical formulas allowing to determine the observer and controller gains. Proper quality indicator of control process is defined and also sample scenario...
Aiming at the time-varying load torque disturbance in the vibration displacement system of continuous casting mold driven by servo motor, an extended state observer (ESO) based backstepping sliding mode control method is proposed. Firstly, a mapping function is established to deal with the non-uniqueness of the nonlinear inverse relationship from eccentric shaft angle to mold displacement. Secondly,...
Gears are used in different industries from machine and equipments manufacturing to automotive industry, from energy industry such as steam and hydraulic turbines, wind turbines to aeronautics such as helicopter and aero plane industries. There is an increasing demand for gears which work at high speeds and carry high loads, so there is more need for gear research and development activities on gear...
Aiming at the problem of existing larger speed fluctuation when the variable frequency air conditioning compressor running at low frequency, the reason of speed fluctuation in the low speed range for compressor is analyzed thoroughly in this paper, a speed fluctuation suppression strategy for the air conditioning compressor is proposed. Firstly, the periodic speed pulsation of compressor is reduced...
Electric Vehicles (EV) equipped with independent drives are capable of controlling the car body motion in multiple degrees-of-freedom with driving force distribution through the suspension reaction force. These electric powertrains could thus suppress primary (1 – 3Hz) and secondary (4 – 10Hz) resonant modes improving ride comfort, road holding and safety of passenger cars. On-Board-Motor (OBM) drivetrains...
In order to meet the requirement of rapid attitude maneuver control and vibration suppression of flexible spacecraft with disturbance and uncertainty, this paper presents a robust control scheme based on path planning and adaptive backstepping control. Firstly, a novel path planning scheme is proposed based on quintic polynomial transition. The continuous and smooth maneuver path is designed to solve...
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