scholarly journals An Identification Method for Rotor Direction Based on Charge Induction

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1380
Author(s):  
Ronghui Chang ◽  
Limin Zhang ◽  
Jiaqun Lin ◽  
Feng Yan ◽  
Yong Chen
Keyword(s):  
Circuit Design ◽  
Sampling Rate ◽  
Normal Operation ◽  
High Noise ◽  
Detection Model ◽  
Induction Mechanism ◽  
Charge Induction ◽  
Detection Circuit ◽  
Sampling Points ◽  
Novel Method

The detection of rotor motion is always key to ensure the normal operation of industrial sewing machines. This paper presents a novel method for rotor detection based on charge induction mechanism, which is suitable for industrial environments with high noise and electromagnetic radiation and is easy to install. Firstly, the principle of measuring rotor rotation based on charge induction is given. Then, the detection model of rotor direction identification based on two detection electrodes is established. Finally, details are given of the detection circuit design and the experiment that was carried out. The results show that the proposed method can effectively identify the noncontact rotor direction with and without occlusion, indicating that the method has excellent anti-interference capability. The accuracy of the method can be further improved by increasing the sampling rate and sampling points of the system.

Simulation of liquid film motor: a charge induction mechanism

2015 ◽  
Vol 19 (1) ◽  
pp. 133-139 ◽  
Author(s):  
M. Nasiri ◽  
R. Shirsavar ◽  
T. Saghaei ◽  
A. Ramos
Keyword(s):  
Liquid Film ◽  
Induction Mechanism ◽  
Charge Induction ◽  
A Charge

Torsional Vibration Detection Using High Sampling Rate and High Resolution Keyphasor Information

2013 ◽  
Author(s):  
Huageng Luo ◽  
Roengchai Chumai ◽  
Nicolas Peton ◽  
Brian Howard ◽  
Arun Menon
Keyword(s):  
Torsional Vibration ◽  
Sampling Rate ◽  
Synchronous Motor ◽  
Rotating Machinery ◽  
Normal Operation ◽  
Machinery Condition Monitoring ◽  
Vibration Detection ◽  
High Sampling ◽  
High Sampling Rate ◽  
Phase Demodulation

Torsional vibration excitation in rotating machinery can cause system reliability issues or even catastrophic failures. Torsional vibration detection and monitoring becomes an important step in rotating machinery condition monitoring, especially for those machines driven by a variable frequency drive (VFD), a pulse width modulation motor (PWM), or a synchronous motor (SM), etc. Traditionally, the torsional vibration is detected by a phase demodulation process applied to the signals generated by tooth wheels or optical encoders. This demodulation based method has a few unfavorable issues: the installation of the tooth wheels needs to interrupt the machinery normal operation; the installation of the optical barcode is relatively easier, however, it suffers from short term survivability in harsh industrial environments. The geometric irregularities in the tooth wheel and the end discontinuity in the optical encoder will sometimes introduce overwhelming contaminations from shaft order response and its harmonics. In addition, the Hilbert Transform based phase demodulation technique has inevitable errors caused by the edge effect in FFT and IFFT analyses. Fortunately, in many industrial rotating machinery applications, the torsional vibration resonant frequency is usually low and the Keyphasor® and/or encoder for speed monitoring is readily available. Thus, it is feasible to use existing hardware for torsional vibration detection. In this paper, we present a signal processing approach which used the Keyphasor/encoder data digitized by a high sampling rate and high digitization resolution analog-to-digital (A/D) convertor to evaluate the torsional vibration directly. A wavelet decomposition (WD) based method was used to separate the torsional vibration from the shaft speed, so that the time history of the torsional vibrations can be extracted without significant distortions. The developed approach was then validated through a synchronous motor fan drive and an industrial power generation system. Detailed results are presented and discussed in this paper.

scholarly journals A Statistic-Based Calibration Method for TIADC System

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Kuojun Yang ◽  
Shulin Tian ◽  
Peng Ye ◽  
Peng Zhang ◽  
Yuanjin Zheng
Keyword(s):  
Sampling Rate ◽  
Calibration Method ◽  
Wide Frequency Range ◽  
Accurate Estimation ◽  
Analog To Digital ◽  
Average Value ◽  
Gain Error ◽  
Sampling Points ◽  
Interleaved Adc ◽  
Time Interleaved

Time-interleaved technique is widely used to increase the sampling rate of analog-to-digital converter (ADC). However, the channel mismatches degrade the performance of time-interleaved ADC (TIADC). Therefore, a statistic-based calibration method for TIADC is proposed in this paper. The average value of sampling points is utilized to calculate offset error, and the summation of sampling points is used to calculate gain error. After offset and gain error are obtained, they are calibrated by offset and gain adjustment elements in ADC. Timing skew is calibrated by an iterative method. The product of sampling points of two adjacent subchannels is used as a metric for calibration. The proposed method is employed to calibrate mismatches in a four-channel 5 GS/s TIADC system. Simulation results show that the proposed method can estimate mismatches accurately in a wide frequency range. It is also proved that an accurate estimation can be obtained even if the signal noise ratio (SNR) of input signal is 20 dB. Furthermore, the results obtained from a real four-channel 5 GS/s TIADC system demonstrate the effectiveness of the proposed method. We can see that the spectra spurs due to mismatches have been effectively eliminated after calibration.

A Novel Method for Refurbishing Used Hot Section Gas Turbine Blades

1995 ◽  
Vol 117 (1) ◽  
pp. 166-171 ◽  
Author(s):  
A. Kempster ◽  
N. Czech
Keyword(s):  
Gas Turbine ◽  
Turbine Blades ◽  
Protective Layer ◽  
Substrate Material ◽  
Corrosion Products ◽  
Normal Operation ◽  
Blade Surface ◽  
Gas Turbine Blades ◽  
Service Period ◽  
Novel Method

During the normal operation of a land-based gas turbine, attack will occur of the gas-washed surfaces of the rotating stationary blades in the turbine hot section. This attack and its intensity can be variable depending on the blade’s position in the turbine hot section. This attack will progressively degrade these gas-washed surfaces even if these surfaces have been previously coated with a protective layer. During the service period of the turbine, it will be necessary to refurbish the blades from the hotter section of the turbine. One of the refurbishment steps will be to provide the blades with a suitable replacement coating to afford protection until the next service period. Conventional refurbishment techniques used to clean the blade surface rely on abrasive cleaning and / or chemical pickling. These processes may be capable of removing superficial oxidation and any residual coating but are not able consistently to remove the substrate material that has suffered from corrosive attack. It is important that this attacked substrate layer be removed completely, otherwise any residual corrosion products, particularly the presence of deeply penetrated sulfides in grain boundaries, could significantly reduce the life of any subsequent coating. The technique described in this paper essentially activates the surface layer of the substrate that is corroded, thus rendering it more easily removed by chemical and physical means. It is possible by this method to remove up to 400 μm of the substrate material and provided that all the corrosion products are contained within this zone, it is demonstrated how this produces a clean unattacked surface that is necessary for any subsequent welding, brazing, or recoating operation.

A Novel Method for Low-Contrast and High-Noise Vessel Segmentation and Location in Venipuncture

2017 ◽  
Vol 36 (11) ◽  
pp. 2216-2227 ◽  
Author(s):  
Yuhe Li ◽  
Zhendong Qiao ◽  
Shaoqin Zhang ◽  
Zhenhuan Wu ◽  
Xueqin Mao ◽  
...  
Keyword(s):  
Vessel Segmentation ◽  
High Noise ◽  
Low Contrast ◽  
Novel Method

scholarly journals Circuit Design of Surface Acoustic Wave Based Micro Force Sensor

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Yuanyuan Li ◽  
Wenke Lu ◽  
Changchun Zhu ◽  
Qinghong Liu ◽  
Haoxin Zhang ◽  
...  
Keyword(s):  
Acoustic Wave ◽  
Surface Acoustic Wave ◽  
Circuit Design ◽  
Force Measurement ◽  
Pressure Sensors ◽  
Force Sensor ◽  
Piezoresistive Sensor ◽  
Detection Circuit ◽  
Micro Force Sensor ◽  
The Stability

Pressure sensors are commonly used in industrial production and mechanical system. However, resistance strain, piezoresistive sensor, and ceramic capacitive pressure sensors possess limitations, especially in micro force measurement. A surface acoustic wave (SAW) based micro force sensor is designed in this paper, which is based on the theories of wavelet transform, SAW detection, and pierce oscillator circuits. Using lithium niobate as the basal material, a mathematical model is established to analyze the frequency, and a peripheral circuit is designed to measure the micro force. The SAW based micro force sensor is tested to show the reasonable design of detection circuit and the stability of frequency and amplitude.

A Novel Fuzzy Self-Adaption PI Control Method of the Var Compensation of Wind Generator

2012 ◽  
Vol 608-609 ◽  
pp. 785-789 ◽  
Author(s):  
Xian Ming Zou ◽  
Jun Yang ◽  
Hongyu Zhang ◽  
Yu Zhu
Keyword(s):  
Reactive Power ◽  
Control Method ◽  
Wind Farms ◽  
Normal Operation ◽  
Pi Control ◽  
Doubly Fed Induction Generator ◽  
Wind Generator ◽  
Novel Method ◽  
Doubly Fed ◽  
The Stability

Aiming at the phenomenon that the doubly fed induction generator (DFIG) can supply active power and absorb reactive power in the range of normal operation involves stability and transient, this paper proposes a novel method based on the fuzzy self-adaption PI control to control TCR to compensate the reactive power of wind farms required, and to improve the stability of voltage in wind farms. In this research, the wind generator model of being regarded as reactive load is established in Simulink of MATLAB. The results show that: the voltage and current distortion of the wind generator can be restrained well by using the SVC system proposed in this paper, and the stability of voltage and current in wind farms can be improved effectively.

Two Elution Mechanisms of MEP Chromatography

2018 ◽  
Vol 20 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Tsutomu Arakawa ◽  
Masao Tokunaga ◽  
Takuya Maruyama ◽  
Kentaro Shiraki
Keyword(s):  
Hydrophobic Interaction ◽  
Positive Charge ◽  
Hydrophobic Interaction Chromatography ◽  
Normal Operation ◽  
Acidic Ph ◽  
Charge Induction ◽  
Pyridine Group ◽  
Ph Range ◽  
Hydrophobic Charge Induction Chromatography ◽  
Positively Charged

MEP (mercapto-ethyl-pyridine) HyperCel is one of the hydrophobic charge induction chromatography (HCIC) resins. Under normal operation, proteins are bound to the MEP resin at neutral pH, at which MEP is not charged, mostly via hydrophobic interaction. MEP has a pyridine group, whose pK is 4.8, and hence is positively charged at acidic pH range. Based on the binding mechanism (i.e., hydrophobic interaction) and the induced positive charge at acidic pH, there may be two ways to elute the bound proteins. One way is to bring the pH down to protonate both MEP resin and the bound protein, leading to charge repulsion and thereby elution. Another way is to use hydrophobic interaction modifiers, which are often used in hydrophobic interaction chromatography, to reduce hydrophobic interaction. Here, we summarize such two possible elution approaches.

Asynchronous Motor Fault Detection Circuit Design

2014 ◽  
Author(s):  
Zongming Li ◽  
Baichao An ◽  
Haoyu Lu ◽  
Qiang Liu ◽  
Liying Yuan
Keyword(s):  
Fault Detection ◽  
Circuit Design ◽  
Asynchronous Motor ◽  
Detection Circuit
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