PIER C | PIER Journals

2024-06-04

PIER C

Vol. 143, 199-207, 2024

download: 141

Simplified Three-Vector Selection Model Predictive Current Control for PMSM Considering Fixed Switching Frequency

Dingdou Wen , Zhuoheng Li , Xiaorui Wei and Zhun Cheng

To address the insufficiency of large computation and unfixed switching frequency in permanent magnet synchronous motor (PMSM) of three-vector model predictive current control (TV-MPCC), simplified three-vector selection model predictive current control (STV-MPCC) for PMSM considering fixed switching frequency is proposed. Firstly, a novel voltage vector selection strategy is constructed by calculating the reference voltage in combination with the deadbeat control and re-dividing the sectors, reducing the number of optimizations from 11 to 5. Then, the current error is introduced in the calculation of the duty cycle to simplify the conventional control algorithm, The current ripple is reduced, and the system switching frequency is fixed. Finally, the experimental results indicate that compared with the conventional TV-MPCC, the d-q axis current ripple has been reduced by 13% and 18% respectively, and the torque ripple has been reduced by 6%, THD decreased from 4.70% to 4.25% and the steady-state performance of the motor is improved.

Simplified Three-vector Selection Model Predictive Current Control for PMSM Considering Fixed Switching Frequency

2024-06-03

PIER C

Vol. 143, 189-198, 2024

doi:10.2528/PIERC24031801

download: 169

Displacement Self-Sensing Control of Permanent Magnet Assisted Bearingless Synchronous Reluctance Motor Based on BP Neural Network Optimized by Improved PSO

Jing Wang , Gai Liu and Huangqiu Zhu

In order to solve the problems of low reliability, low integration, and high cost brought by mechanical sensors in the control system of permanent magnet-assisted bearingless synchronous reluctance motor (PMa-BSynRM), a displacement self-sensing method of the Bback propagation (BP) neural network left-inverse system under the optimization of an improved particle swarm algorithm is proposed. Firstly, the working principle of PMa-BSynRM is introduced, and the mathematical model of PMa-BSynRM is derived. Secondly, the suspension force model is established to prove the left reversibility of the PMa-BSynRM displacement subsystem on the basis of the observation principle of the left reversible system. Thirdly, the weights of BP neural network are optimized by using the improved particle swarm algorithm to avoid local optimum, and the final weights are obtained to complete the construction of the displacement self-detection control system. On this basis, velocity change and anti-interference simulations are conducted to prove the tracking performance of the displacement system. Finally, static suspension, velocity change, and anti-interference experiments are executed which verify the accuracy and feasibility of the proposed displacement self-detection system.

Displacement Self-sensing Control of Permanent Magnet Assisted Bearingless Synchronous Reluctance Motor Based on BP Neural Network Optimized by Improved PSO

2024-06-03

PIER C

Vol. 143, 181-187, 2024

doi:10.2528/PIERC24021502

download: 174

Control Signals for NOMA-VLC Systems

Safwan Hafeedh Younu and Mohamad A. Ahmed

In wireless communication systems, a control signal (CS) plays a vital role in managing the connection between transmitters (Txs) and the user equipment (UEs). This work presents CSs for non-orthogonal multiple access (NOMA)-based on visible light communication (VLC) systems. Moreover, pairing schemes, successive interference cancellation (SIC), and load balancing are considered with the NOMA-VLC technique for enhancing the entire performance. The CSs, which are single tones or can be described as unmodulated signals, are exploited to estimate the channel between Txs and UEs, and to evaluate the amount of interference at each UE. Thus, a controller, which is employed to manage the connections between Txs and UEs, can balance the load between Txs based on the level of interference at each UE. Each Tx is allocated a unique CS, i.e. a single-tone frequency. A power measurement unit (PMU) is utilized at each UE for measuring the power of each CS. Therefore, the controller divides the UEs into small groups based on the feedback signals from the PMU, then each group is connected to one Tx. Besides, CSs are used to find the optimum number of UEs that can be served by each Tx with a particular data rate of 50 Mbps and with an acceptable error probability of 10^-6, by utilizing on-off keying (OOK) modulation scheme.

2024-06-01

PIER C

Vol. 143, 169-180, 2024

doi:10.2528/PIERC24022708

download: 315

Recent Trends in Compact Planar Antennas at 5G Sub-6 GHz and mmWave Frequency Bands for Automotive Wireless Applications: a Review

Ashish Kumar , Mohammad Aljaidi , Manpreet Singh , Mohammed Sanad Alshammari , Amjad A. Alsuwaylimi and Sami M. Alenezi

5G wireless communication offers higher channel capacity, high data rate, sufficient bandwidth, enhanced coverage, and reliable link as compared to the previous generation mobile networks. Also, 5G becomes more relevant with the recent launches of low earth orbit satellites by various ventures like starlink, amazon, one web, etc. As these satellites have heights up to the range from 300 km to 1000 km, the free space path loss decreases drastically which in turn improves the signal reliability and efficient communication at dead spots. With these advancements, antenna researchers have the freedom to design compact, easy to manufacture, with adequate gain user equipment terminal antennas which can be easily integrated in the modern passenger car body. This paper will focus on the recent development in the design considerations of the compact antenna design at sub-6 GHz (n78 frequency band) and mm wave (n278 frequency band) according to 3gpp standards. This manuscript also discusses the various design specifications like selection of material for antennas, design complexity, feeding methods, fabrication and measurement challenges and performance parameters which include reflection coefficient, gain, polarization, axial ratio, cross polarization discrimination, radiation efficiency, radiation pattern shape, etc. The proposed antenna design considerations will facilitate the possible integration into the various parts of the car body according to the recent vehicular applications to uninterrupted communication.

Recent Trends in Compact Planar Antennas at 5G Sub-6 GHz and mmWave Frequency Bands for Automotive Wireless Applications: A Review

2024-06-01

PIER C

Vol. 143, 161-168, 2024

doi:10.2528/PIERC24031101

download: 117

Fault Diagnosis Output of Motor Bearings Based on Relieff Feature Selection

Ming Tang , Aiyuan Wang and Zhentian Zhu

The problem of unstable vibration signal and accurate fault feature extraction of motor bearing fault causes the low accuracy of motor bearing fault diagnosis. In order to improve the accuracy of motor bearing fault diagnosis, the variational mode decomposition (VMD) is used to decompose the vibration signal and combine with the convolutional neural network (CNN).The bearing faults are categorized into inner ring wear, outer ring wear and cage fracture; then each category of faults is further subdivided into the degree of loading, which is categorized into 0, 25% and 50%, with a total of 9 cases. In order to select sensitive fault features, the vibration signals of motor bearings in three dimensions are collected, decomposed into multiple endowment modal function (IMF) components by VMD. The energy entropy of each IMF in each dimension is extracted, and the sensitive fault features are selected by feature selection (ReliefF), and then input into CNN for fault diagnosis. At the same time, the fault diagnosis of transverse vibration signal and three-dimensional vibration signal is also carried out respectively. The experimental results show that the accuracy of the method is greatly improved, and the fault diagnosis can be realized.

Fault Diagnosis Output of Motor Bearings Based on ReliefF Feature Selection

2024-05-28

PIER C

Vol. 143, 151-160, 2024

doi:10.2528/PIERC24022808

download: 144

Design of a CSRR Dual-Port Patch Antenna with Elliptical Slots on Ground Plane for Wireless Communication

Manjula Sanugomula and Ketavath Kumarnaik

This paper introduces a complementary split ring resonator (CSRR) patch antenna with elliptical slots on the ground plane for wireless communication, significantly amplified by placing two conducting elements over the substrate. The dimensions of the designed CSRR dual element multiple-input-multiple-output (MIMO) antenna are 16 x 32 mm² (0.66λ x 1.33λ). In this paper, the CSRR dual element MIMO antenna with an elliptical DGS resonates at 11.523 GHz, 12.305 GHz, and 15.178 GHz with reflection coefficients of -22.67 dB, -26.25 dB, and -47.65 dB respectively. It presents an impressive wide impedance bandwidth of 1.462 GHz covering 11.523 GHz and 12.305 GHz resonating frequencies and 1.446 GHz at 15.178 GHz resonance. The proposed design gives a gain of 5.29 dBi, 6.12 dBi, and 5.97 dBi for the resonating frequencies respectively. The results show a minimum envelope correlation coefficient (<0.025) and a significant diversity gain (>9.85) across the entire bandwidth. The measured results are close to the simulated ones, confirming the efficiency of the triple resonating frequencies with wideband, high-gain antenna design used for wireless communications for faster data transmission rates.

Design of a CSRR Dual-port Patch Antenna with Elliptical Slots on Ground Plane for Wireless Communication

2024-05-24

PIER C

Vol. 143, 141-150, 2024

doi:10.2528/PIERC24031202

download: 151

Reduction of Specific Absorption Rate Using a-Shaped Electromagnetic Band Gap for Quad Port MIMO Antenna

Govindarao Tamminaina and Ramesh Manikonda

This work designs an electromagnetic band gap structure-based quad port rectangular MIMO antenna to operate in the 5G new radio (NR) sub-6 GHz n79 band, with a frequency range of 4.3-5.0 GHz. To achieve optimal radiating element isolation with the least complexity, MIMO antennas' four radiating elements are oriented orthogonally using an A-shaped electromagnetic band gap (EBG) structure. The EBG structure is located between the human phantom model and the MIMO antenna. The MIMO antenna's measurements are 40 × 40 × 1.6 mm³, and it is implemented on an FR-4 substrate with whole ground. Due to EBG structure, the mutual coupling is improved to -26.0 dB. The ECC, DG, and CCL were also calculated. In addition, the SAR (specific absorption rate) value is reduced to 0.22 w/kg. The MIMO antenna is simulated using HFSS software. The vector network analyzer (VNA), model Anritsu MS 2037C is used to measure the various MIMO antenna parameters.

Reduction of Specific Absorption Rate Using A-shaped Electromagnetic Band Gap for Quad Port MIMO Antenna

2024-05-22

PIER C

Vol. 143, 131-139, 2024

doi:10.2528/PIERC24031303

download: 82

A Miniaturized Double Sided Vivaldi Antenna with Enhanced Radiation Traits for EW Applications

Mayank Vishwakarma , Puthalpattu Nagaraja Rao and Satyanarayana Vuta

This paper presents a compact double sided Ultra-Wideband (UWB) vivaldi antenna with corrugated structure. The proposed antenna is designed to operate from 5 GHz to 20 GHz frequency band. A comprehensive analysis of the antenna is carried out for its design, optimization, and performance especially for enhanced bandwidth and improved radiation characteristics. The antenna structure consists of vivaldi section which is printed on top and bottom layers of multi-layer printed circuit board (PCB) and fed with microstrip to strip lines transition. The antenna is fabricated and measured its return loss and radiation characteristics. The measured peak gain is 10.25 dBi at 17 GHz and return loss is better than -10 dB over the band 5 GHz to 20 GHz. Symmetrical radiation properties are observed over the band with excellent radiation characteristics especially in lower frequency bands as a result of comprised corrugated structure. Also, the far-field radiation pattern is symmetrical and directive throughout the operating band. The proposed design finds a suitable application in the field of an electronic warfare, precision ranging, microwave imaging.

A Miniaturized Double Sided Vivaldi Antenna with Enhanced Radiation Traits for EW Applications

2024-05-16

PIER C

Vol. 143, 121-129, 2024

doi:10.2528/PIERC24031308

download: 210

Machine Learning-Based Optimization of Hexagon-Shaped Fractal Antenna for Ultra-Wideband Communications

Sai Sampreeth Indharapu , Anthony N. Caruso , Travis D. Fields and Kalyan C. Durbhakula

In the wireless communication industry, achieving gigabit-per-second data rates with low-profile, ultra-wideband (UWB) microstrip patch antennae poses a significant challenge. Conventional optimization algorithms, though effective, are often computationally expensive, particularly for complex antenna geometries with high degrees of freedom. There is an imperative need for new methodologies to address this challenge and revolutionize the antenna optimization process. Successful and timely development of antennas relies on the efficiency and computational speed of optimization algorithms, full-wave electromagnetic (EM) solvers, and the intuition of radio frequency engineers. To mitigate the dependence on complex and time-consuming processes, we propose an efficient machine learning (ML)-based antenna optimization methodology that minimizes optimization time by more than 90%. This paper aims to apply and study the performance of two specific ML models, the radial basis function (RBF) and the least squared regression (LSR) models, in the bandwidth optimization without increasing the aperture area of a hexagon-shaped fractal antenna. The hexagon-shaped fractal antenna was chosen for its UWB characteristics, low profile, and high degrees of freedom (10 adjustable parameters). The reflection coefficient response of a hexagon-shaped fractal antenna is predicted by the trained RBF and LSR models and further optimized by the genetic algorithm (GA). The proposed approach stands out among other notable works in this research domain, especially for ultrawideband (UWB) applications, by prioritizing the optimization of the mean of |S₁₁| across the entire frequency range instead of solely targeting individual frequency points. The GA-based optimization using trained ML models has increased the bandwidth by 30.20% and reduced the computational time by 90% compared to conventional optimization without increasing the physical or electrical size of the antenna. Simulation and measurement results concurred with a maximum difference of 5%, demonstrating the efficacy of the ML approach for antenna optimization.

Machine Learning-based Optimization of Hexagon-shaped Fractal Antenna for Ultra-wideband Communications

2024-05-07

PIER C

Vol. 143, 109-119, 2024

doi:10.2528/PIERC24022104

download: 130

Simulation Study of Digital Spatial Processing in Conditions of Tropospheric Propagation of Radio Waves for Telecommunication Applications

Ilia Peshkov

In this paper, the propagation of electromagnetic rays in a tropospheric waveguide and spatial processing using digital antenna arrays are studied. The beam traveling through the layers of the atmosphere depends on the refractive index and its vertical change. In this regard, conditions may arise when radio rays propagate in a waveguide manner at low altitudes. In this case, attenuation takes place, and the effect of multipath fading may also occur, when several rays reflected from different layers of the troposphere and with various spatial coordinates in elevation arrive at the receiver. It is proposed to apply digital antenna arrays to increase the range and reliability of radio communication through the tropospheric waveguide. Parabolic equations are utilized to estimate the path loses of radio waves of the centimeter wavelength. A ray-tracing algorithm via a tropospheric waveguide is used to estimate the mutual phases in the aperture of the receiving array. Bit error rate curves were obtained depending on the geometry of the antenna arrays after the signal passed through the tropospheric waveguide.

Simulation Study of Digital Spatial Processing in Conditions of Tropospheric Propagation of Radio Waves for Telecommunication Applications

2024-05-06

PIER C

Vol. 143, 99-107, 2024

doi:10.2528/PIERC24031602

download: 188

Research on Induced Electrical Characteristics of Agricultural Machinery Operating Under Ultra High Voltage ac Transmission Lines in Agricultural Area

Bin Hu , Meng Zhang , Xiaohe Zhao , Bingchen Hou and Zhongqing He

In plain areas, the majority of the ultra-high voltage(UHV) transmission corridors are located in farmland. The induced voltage is generated on the metal casing of the machinery when agricultural machines are working on the ground near the transmission line. If the human body touches, transient electric shock(TES) may occur, causing displeasure and alarm to workers. Therefore, it is crucial to study the induced electrical characteristics in such scenarios. In this article, the finite element method (FEM) was employed to establish a model integrating a 1000 kV transmission line, tractor, and human body, and the induced voltage of the tractor and human body under the transmission line was calculated. Subsequently, a TES model was developed to calculate the current when an electric shock occurs. Finally, an experimental system was constructed in the area beneath the 1000 kV UHV AC line to measure the current characteristics of the human body during the TES. The results demonstrate that the induced voltage is contingent upon the position of research object and whether it is insulated from the ground. Additionally, ground conditions significantly influence the TES current induced by the voltage. Due to the electromagnetic shielding effect of the tractor's metal casing, the TES current experienced by the driver inside the machine is minimized. For ground staff, when the human body is insulated from the ground, the transient electric shock current they bear is smaller than that of the human body grounded.

Research on Induced Electrical Characteristics of Agricultural Machinery Operating under Ultra High Voltage AC Transmission Lines in Agricultural Area

2024-05-05

PIER C

Vol. 143, 87-98, 2024

doi:10.2528/PIERC24031301

download: 254

Wireless Power Transfer System for Cardiac Pacemakers Based on Multi-Coil Series Magnetic Integration

Xiaoheng Yan , Jinshu Yao , Weihua Chen and Yuhang Song

We proposed a wireless power transfer system for cardiac pacemakers utilizing a multi-coil series magnetic integrated inductor-capacitor-capacitor/none (LCC-N) circuit topology operating at 50 kHz to reduce the volume of wireless power transfer systems for implanted pacemakers. Firstly, we established a mathematical model of LCC-N compensation topology and analyzed the relationship between the mutual inductance of the compensation and receiving coil and the system's transmission efficiency. The conclusion that the anti-offset performance of the system can be improved by using the change of the mutual inductance value was obtained. Secondly, the optimal coil structure was obtained via parameterized scanning, and a wireless power transfer system model for LCC-N was established for finite element simulation. The comparison of magnetic field strength was made between integrated and traditional non-integrated structures under aligned and offset conditions. Finally, the finite element simulation software ANSYS was adopted to establish a human body model, analyze the electromagnetic interference of the system to the human body, and evaluate the system's safety. Experimental results validated that the transmission efficiency of the system can reach 68.37%, and the output power was 1.47 W under multi-coil series magnetic integrated structure when the transmission distance was 8 mm. The transmission efficiency remained 57.87% even with a horizontal offset of 8 mm, which is 13% higher than the traditional non-integrated structure.

Wireless Power Transfer System for Cardiac Pacemakers Based on Multi-coil Series Magnetic Integration

2024-05-01

PIER C

Vol. 143, 75-86, 2024

doi:10.2528/PIERC24031603

download: 193

Mutual Inductance Calculation Method of Rectangular Coils with Bilateral Bounded Single-Hole Type Magnetic Medium in Wireless Power Transfer Systems

Lingjun Kong , Zhongbang Chen , Changxuan Hu , Chenxi Zhang , Jianbin Wang , Xin Zhou , Lin Jia and Zhongqi Li

The mutual inductance between the transmitting and receiving coils is one of the critical parameters of the wireless power transfer system, and an accurate mutual inductance calculation method can provide a reliable theoretical basis for the optimization of the coil structure of the wireless power transfer system. The addition of magnetic medium materials on both sides of the rectangular coil can effectively increase the mutual inductance, but there is no study on the mutual inductance calculation method for a rectangular coil with a bilateral bounded single-hole type magnetic medium. In this paper, the space vector domain synthesis method is proposed to solve the analytical value of mutual inductance, which solves Poisson's and Laplace's equations by separating the variables to obtain the magnetic vector potential in each region, and combines with the magnetic field boundary conditions to obtain the mutual inductance calculation formula by utilizing different dimensional vector syntheses. An experimental set of wireless power transfer systems with bilateral bounded single-hole type magnetic medium rectangular coils is also constructed, and the maximum error of the mutual inductance calculation value, experimental value, and simulation value is 5.82%, which verifies the effectiveness of the method proposed in this paper. The model proposed in this paper saves 5.86% of the material compared with the rectangular magnetic medium structure under the same parameters, and the mutual inductance is up to 99% of the rectangular magnetic medium structure.

Mutual Inductance Calculation Method of Rectangular Coils with Bilateral Bounded Single-hole Type Magnetic Medium in Wireless Power Transfer Systems

2024-04-29

PIER C

Vol. 143, 67-74, 2024

doi:10.2528/PIERC24031304

download: 227

High Isolated Defected Ground Structure Based Elliptical Shape Dual Element MIMO Antenna for S-Band Applications

Praveen Kumar , Ajit Kumar Singh , Ranjeet Kumar , Rashmi Sinha , Santosh Kumar Mahto , Arvind Choubey and Ahmed Jamal Abdullah Al-Gburi

This research suggests a compact, wideband Multiple Input Multiple Output (MIMO) antenna designed for S-band applications, emphasizing high isolation between closely positioned antenna elements. Achieving this isolation is accomplished through the implementation of a Defected Ground Structure (DGS) technique. The DGS is realized by etching two elliptical patterns on an economical FR-4 substrate with inherent loss properties. Three rectangular slots and two L-shaped stubs are introduced to improve isolation and minimize the size of antenna increment by lowering surface wave propagation. To validate the proposed layout, a physical prototype was constructed for a direct comparison of its performance with the simulated parameters. The results demonstrated highly favorable outcomes, including Diversity Gain (DG) exceeding 9.97 dB, Envelope Correlation Coefficient (ECC) registering below 0.05, Mean Effective Gain (MEG) lower than -3 dB, Total Active Reflection Coefficient (TARC) below 0.4, and Channel Capacity Loss (CCL) less than 0.3. Furthermore, the current distribution and radiation pattern were found to be highly suitable for applications in the S-band and the lower part of the C-band, encompassing technologies like Bluetooth, WiFi, WiMAX, 4G, and 5G.

High Isolated Defected Ground Structure Based Elliptical Shape Dual Element MIMO Antenna for S-band Applications

2024-04-29

PIER C

Vol. 143, 57-66, 2024

doi:10.2528/PIERC24022702

download: 244

A Compact Four Port High-Isolation SIW-Backed Self-Quadruplexing Antenna with a Swastik Shaped Slot for C Band Applications

Anil Kumar Katta and Praveen Babu Choppala

A compact planar self-quadruplexing antenna backed with the SIW technology with high isolation between the input ports is designed and demonstrated for the simultaneous quad-band operation of the antenna. The SIW cavity is integrated with a Swastik shaped slot and two metallic vias to generate four distinct frequency bands with high gain and low cross polarization. Utilizing four distinct orthogonal patches with different lengths, each independently connected to a 50-Ω microstrip feed line, makes the antenna operate at four frequency bands of 4.8, 5.5, 6.6, and 7.6 GHz. The minimum value of Front-To-Back-Ratio (FTBR) is 18 dB, and the minimum isolation between the input ports is 28.4 dB. The measured values of peak gains in the frequency bands 4.8, 5.5, 6.6 and 7.6 GHz are 5.05, 6.20, 6.45 and 6.32 dBi, respectively. Hence, a single antenna consists of four signals transmitting or receiving simultaneously from four individual input ports without interfering with each other and with high isolation between the input ports confirms the self-quadruplexing property of the antenna. This antenna configuration enables the independent tuning of each resonant frequency according to specific application needs by manipulating a single parameter, that is the length of the patch and without disturbing other performance parameters of the antenna. To validate the simulation results, the antenna is fabricated and tested. The measurement findings match the simulation results closely, which confirms the quad-band operation of the antenna design. Simple configuration, compact size, high gain, and low cross polarization of the antenna make the proposed planar antenna suitable for practical multiband applications and for handheld transceivers with high isolation between the input ports.

A Compact Four Port High-isolation SIW-backed Self-quadruplexing Antenna with a Swastik Shaped Slot for C Band Applications

2024-04-26

PIER C

Vol. 143, 45-56, 2024

doi:10.2528/PIERC24030903

download: 164

Design and Evaluation of 5-DOF Magnetic Bearing System for Saucer-Shaped Flywheel Battery

Weiyu Zhang , An Li and Jingwen Wang

In this study, a novel vehicle-mounted flywheel battery system is proposed, which can effectively balance the load capacity with margin, strong anti-interference, uncoupled magnetic circuit and low energy consumption. The proposed new flywheel battery adopts multiple magnetic circuits, reducing the number of permanent magnets and the complexity of the magnetic circuit. It is worth mentioning that the proposed ``side branch'' radial/tilting shared magnetic circuit can realize the main bearing function of the flywheel weight, and the axial biased magnetic field is used to suspend the near ``zero weight'' flywheel, so that the flywheel can withstand a certain interference margin in the axial direction, and then improve the active disturbance rejection and effectively reduce the control loss. After optimization, the unique overall structure of the flywheel battery can significantly improve the overall performance of the flywheel battery. Finally, the stiffness, decoupling, and anti-interference experiments are carried out, and the experimental results show that the proposed flywheel battery has good performance.

Design and Evaluation of 5-DOF Magnetic Bearing System for Saucer-shaped Flywheel Battery

2024-04-24

PIER C

Vol. 143, 35-43, 2024

doi:10.2528/PIERC24022901

download: 204

Research on Electromagnetic Vibration and Noise Suppression of PMaSynRM with Slotted Stator and Rotor

Zhentian Zhu , Aiyuan Wang and Ming Tang

Permanent magnet assisted synchronous reluctance motor (PMaSynRM) has been widely concerned, but the research on the vibration and noise of this kind of motor is relatively limited. In addressing the problem of significant vibration noise caused by radial electromagnetic force waves in PMaSynRM. The research explores a motor vibration and noise suppression solution involving stator slotting and rotor magnetic isolation hole opening. The study analyzed the impact of different slotting parameters on the radial electromagnetic force and air gap magnetic flux density of the motor and compared it with the solution involving slotting of the stator teeth only and magnetic isolation hole opening of the rotor only. Finally, the modal, vibration response and noise response of the motor after slotting are analyzed and verified. The results show that the amplitude of radial electromagnetic force and the total harmonic distortion rate of the air gap magnetic flux density of the motor are significantly reduced by opening the stator auxiliary slot and the rotor magnetic isolation hole. The maximum vibration acceleration of the motor is reduced by 33.44 mm/s², and the peak A-weighted sound pressure level of the motor decreases by 5.49 dBA.

Research on Electromagnetic Vibration and Noise Suppression of PMaSynRM with Slotted Stator and Rotor

2024-04-22

PIER C

Vol. 143, 23-33, 2024

doi:10.2528/PIERC24030301

download: 209

Reconfigurable Designs of Sectoral Microstrip Antennas for Wideband and Circularly Polarized Response

Venkata A. P. Chavali , Amit A. Deshmukh , Aarti G. Ambekar , Hari Vasudevan and Tushar V. Sawant

Gap-coupled designs of Sectoral microstrip antenna for 90˚ and 45˚ sectoral angle are proposed for wideband and circularly polarized response. On total substrate thickness of ~0.1 g, proximity fed design of 90˚ Sectoral patch yields simulated bandwidth of 827 MHz (50.41%) with a peak gain of 8.1 dBi, whereas its gap-coupled configuration with parasitic 45˚ Sectoral patches yields simulated bandwidth of 1336 MHz (69.11%) with a peak gain of 8.0 dBi. A gap-coupled design of two 90˚ Sectoral patches is presented in which orthogonal directions of the fundamental mode currents over the aperture are maintained. This yields circularly polarized response with axial ratio bandwidth of 709 MHz (34.88%), which lies inside the impedance bandwidth of 1103 MHz (60.09%). It offers a peak gain of larger than 7 dBi across the axial ratio bandwidth. To achieve all these operational features using a single patch, a reconfigurable design of Sectoral patches is proposed that yields similar wideband and circularly polarized characteristics. Thus, present study provides a wideband and circularly polarized design that offers either impedance bandwidth of more than 65% or axial ratio bandwidth of nearly 35%. For achieved antenna response, the proposed designs fulfill the requirements of LTE (band 65, 66, and 70) and various aeronautical service mobile satellite bands (1610-2300 MHz). Experimental validation for the obtained results is carried out that shows close matching.

Reconfigurable Designs of Sectoral Microstrip Antennas for Wideband and Circularly Polarized Response

2024-04-22

PIER C

Vol. 143, 11-21, 2024

doi:10.2528/PIERC24011602

download: 180

Human Motion Recognition Based on Feature Fusion and Transfer Learning

Xiaoyu Luo and Qiusheng Li

In order to solve the problem that the recognition accuracy of human motion is not high when a single feature is used, a feature fusion human motion recognition method based on Frequency Modulated Continuous Wave (FMCW) radar is proposed. By preprocessing the FMCW radar echo data, the range and Doppler parameters of human motions are obtained, and the range-time feature map and Doppler-time feature map datasets are constructed. In order to fully extract and accurately identify the human motion features, the two features are fused, and then the two features maps and feature fusion spectrograms are put into the VGG16 network model based on transfer learning for identification and classification. Experimental results show that this method can effectively solve the problem of lack of information and recognition rate of single feature motion recognition, and the recognition accuracy is more than 1{\%} higher than that of the single feature recognition method.

Human Motion Recognition Based on Feature Fusion and Transfer Learning

2024-04-21

PIER C

Vol. 143, 1-10, 2024

doi:10.2528/PIERC24030601

download: 145

Harmonic Closed-Loop Model Combined Predictive Fault-Tolerant Control of Double Parallel Rotor Permanent Magnet Synchronous Motor

Hai Pu

Double Parallel Rotor Permanent Magnet Synchronous Motors exhibit superior performance and compact size, but the growing trend of electrification imposes higher demands on them. This study proposes a predictive fault-tolerant control integrating a closed-loop identification model and conducts experiments on Double Parallel Rotor Permanent Magnet Synchronous Motors. Results indicated that the proposed closed-loop identification model, along with its fractional-order lead-lag compensator module, effectively optimized motor performance, reducing average tracking error by 78.36%. Additionally, with demagnetization faults, the predictive fault-tolerant control outperformed traditional fault-tolerant control in speed, current, and torque fault-tolerant control, demonstrating superior performance. Through 10 weeks of practical application records, Double Parallel Rotor Permanent Magnet Synchronous Motors achieved a working accuracy of 95%-99% under the closed-loop identification model, with recall rates reaching 92%-96% in fault-tolerant scenarios. In both natural and simulated demagnetization fault situations, 97.69% of Double Parallel Rotor Permanent Magnet Synchronous Motors could continue normal operation. This research holds positive significance for the development of motor systems and enhancing their adaptability in the trend of electrification.