Double Three-phase Research Articles

Electric Power Flow Control in Double Three-Phase Machines without Shift between Magnetic Axes

This paper examines the control strategy adopted for six-phase machines that have been designed as double three-phase machines without a displacement between the magnetic axes of the two sets of three-phase windings (6PH-ZS). The approach is based on vector control principles, enabling the independent control of direct- and quadrature-current components in both three-phase windings. The advantages of such an approach stem from the flexibility of the current distribution between windings, which aims to achieve the required flux and torque. The proposed control strategy is considered for both motor and generator operating regimes. However, an additional quasi-transformer regime is also addressed. While the classic operation regime requires the machine to produce either driving or generating/braking torque, the quasi-transformer regime enables the control of electric power flow between two three-phase windings. A theoretical analysis of the machine model and control algorithm for the flow of electric power through machines is presented for the three aforementioned operating regimes. Verification of the proposed control algorithm is performed through extensive experimental verification.

Design and Analysis of FLC based Speed Control for a Five-Leg Inverter Fed a Dual-Induction Motor System

This paper proposes progressed speed control for a five-leg voltage source inverter (FLVSI) that drives the double three-phase induction motor framework utilized in mechanical assembling measures. The serious speed control technique comprises of two regulators: 1) the first is a slip regulator that fulfills the application necessity, i.e., to control the mechanical speed of two engines similarly paying little mind to the heap condition. 2) The second is a point regulator that fulfills the FLVSI necessity, i.e., to control the stage point distinction between the two engines for limiting the regular leg current on the grounds that the basic leg current can be twice higher than other leg's current relying upon the activity state of the double motor. Dependability investigation of the two regulators under current speed control is actualized, and the entire presentation of the serious speed control for the FLVSI-took care of double engine drive framework is appeared to recognize its attainability through the simulation results.

Elite male table tennis matches diagnosis using SHAP and a hybrid LSTM–BPNN algorithm

This study adopts a new approach, SHapley Additive exPlanation (SHAP), to diagnose the table tennis matches based on a hybrid algorithm, namely Long Short-Term Memory–Back Propagation Neural Network (LSTM–BPNN). 100 male singles competitions (8535 rallies) from 2019 to 2022 are analyzed by a hybrid technical–tactical analysis theory, which hybridizes the double three-phase and four-phase evaluation theories. A k-means cluster analysis is conducted to classify 59 players’ winning rates into three levels (high, medium, and low). The results show that LSTM–BPNN has excellent performance (MSE = 0.000355, MAE = 0.014237, RMSE = 0.018853, and {mathrm{R}}^{2} = 0.988311) compared with six typical artificial intelligence algorithms. Using LSTM–BPNN to calculate the SHAP value of each feature, the global results find that the receive-attack and serve-attack phases of the ending match have essential impacts on the mutual winning probabilities. Finally, case applications show that the SHAP can directly obtain each feature importance on one or more matches, which is more objective and reliable than the traditional simulation method. This research explores an innovative way to understand and analyze matches, and these results have implications for the performance analysis of table tennis and related racket sports.

Double three-phase permanent magnetic motor based on the smallest copper consumption and maximum torque single phase lack of phase compromise and tolerance error control

In multiphase motors, the consumption of stator copper and the output of torque are a pair of constraints affecting motor control performance. According to the constraint relationship between the them, this paper proposes a method to balance the consumption of copper and the output of torque by using the weight coefficient. Through this method, the efficient control of fault-tolerant motors can be realized, and the balance of output torque and efficiency can be realized. Finally, the accuracy of the control strategy is verified by the motor loading platform.

Technical and tactical diagnosis model of table tennis matches based on BP neural network

BackgroundThe technical and tactical diagnosis of table tennis is extremely important in the preparation for competition which is complicated by an apparent nonlinear relationship between athletes’ performance and their sports quality. The neural network model provides a high nonlinear dynamic processing ability and fitting accuracy that may assist in the diagnosis of table tennis players’ technical and tactical skill. The main purpose of this study was to establish a technical and tactical diagnosis model of table tennis matches based on a neural network to analyze the influence of athletes’ techniques and tactics on the competition results.MethodsA three-layer Back Propagation (BP) neural network model for table tennis match diagnosis were established. A Double Three-Phase evaluation method produced 30 indices that were closely related to winning table tennis matches. A data sample of 100 table tennis matches was used to establish the diagnostic model (n = 70) and evaluate the predictive ability of the model (n = 30).ResultsThe technical and tactical diagnosis model of table tennis matches based on BP neural network had a high-level of prediction accuracy (up to 99.997%) and highly efficient in fitting (R2 = 0.99). Specifically, the technical and tactical diagnosis results indicated that the scoring rate of the fourth stroke of Harimoto had the greatest influence on the winning probability.ConclusionThe technical and tactical diagnosis model of table tennis matches based on BP neural network was highly accurate and efficiently fit. It appears that the use of the model can calculate athletes’ technical and tactical indices and their influence on the probability of winning table tennis matches. This, in turn, can provide a valuable tool for formulating player’s targeted training plans.

Current Control Method for Independent Double Three-phase Winding Interior Permanent Magnet Synchronous Motor Applying Model Predictive Control

Current Control Method for Independent Double Three-phase Winding Interior Permanent Magnet Synchronous Motor Applying Model Predictive Control

Double three-phase PMSM structures for fail operational control

This paper deals with permanent magnet synchronous motors (PMSM) structures. Especially their double three-phase arrangements are analysed in detail. Comparison of three different structures is treated. Non-overlapping concentrated winding is the first analysed structure. Distributed winding arrangement with interlaced sub-systems and also distributed winding arrangement with segregated sub-systems follows.The behaviour of all motor structures during normal operation is the same but the properties during faults are different. The motor behaviour during active short circuit (ASC) is discussed. ASC of whole motor and also partial ASC tests were performed. Current waveforms in different operating points are compared. Results show differences of individual structures with respect to operation during fault.

Double Independent Three-Phase Winding Permanent-Magnet Synchronous Motors with Iron Loss

Double Independent Three-Phase Winding Permanent-Magnet Synchronous Motors with Iron Loss

Novel Pulse Pattern for PWM Double Inverters with Single Shunt Current Detection to Reduce Torque Ripple of Double Three-Phase Wound PMSM

Novel Pulse Pattern for PWM Double Inverters with Single Shunt Current Detection to Reduce Torque Ripple of Double Three-Phase Wound PMSM

独立二重三相巻線永久磁石同期モータのモード分担形電流制御

独立二重三相巻線永久磁石同期モータのモード分担形電流制御

異なる巻線起因特性をもつ独立二重三相巻線永久磁石同期モータの効率駆動法

異なる巻線起因特性をもつ独立二重三相巻線永久磁石同期モータの効率駆動法

Double Three-phase Induction Machine Modeling for Internal Faults Simulation

Multi-phase induction motors present excellent characteristics for faulty tolerant operation. Among them, six-phase induction motors, which are among the most used, exhibit two types of configuration: the double three-phase and the six-phase with single neutral. The double three-phase presents the advantage of reducing harmonics with its symmetric winding. This article presents a new modeling of the double three-phase induction machine for internal faults simulation. The developed model is composed by two sets of three-phase stator windings forming two stars. The model considers an arbitrary displacement (α) between stator stars, allowing the simulation of this type induction machines with different configurations, with 60° displacement used herein. The simulations of internal faults, such as stator windings or rotor faults, are both considered in the proposed model, allowing the machine study under abnormal conditions. The double three-phase induction machine model was fully implemented in real coordinates, making it possible to simulate stator and rotor faults without being necessary to change system equations coordinate. Several examples allow verifying the characteristics of the proposed model and its application for internal fault analysis. Experimental results are also presented to validate the obtained simulation results.

Multiphase starter generator for 48V mini-hybrid powertrain: design and testing

This paper focuses on the design and experimental test results of a belt-driven starter generator for 48-V mini-hybrid powertrains. The functionalities required of the system are engine startup, launch assistant torque, regenerative braking, battery charging, and early fuel cutoff. The cost-effective electrical machine must provide high starting torque and wide constant power speed range, both in motor and generator modes. The authors outline the motivations of the electrical machine topology selection in relation to the specifications and constraints. In particular, a double three-phase induction machine has been selected as a suitable candidate. The aim of this paper is to summarize the design challenges of such kind of electrical machines, mainly subordinated to electromechanical and thermal issues imposed by the considered hybridization solution. Details of the machine design are presented, including a study on multilayer bar stator windings and on rotor slot design. Finally, predicted and measured performances of the prototype are reported and discussed for validation purposes.

Design of High Performance Permanent-Magnet Synchronous Wind Generators

This paper is devoted to the analysis and design of high performance permanent-magnet synchronous wind generators (PSWGs). A systematic and sequential methodology for the design of PMSGs is proposed with a high performance wind generator as a design model. Aiming at high induced voltage, low harmonic distortion as well as high generator efficiency, optimal generator parameters such as pole-arc to pole-pitch ratio and stator-slot-shoes dimension, etc. are determined with the proposed technique using Maxwell 2-D, Matlab software and the Taguchi method. The proposed double three-phase and six-phase winding configurations, which consist of six windings in the stator, can provide evenly distributed current for versatile applications regarding the voltage and current demands for practical consideration. Specifically, windings are connected in series to increase the output voltage at low wind speed, and in parallel during high wind speed to generate electricity even when either one winding fails, thereby enhancing the reliability as well. A PMSG is designed and implemented based on the proposed method. When the simulation is performed with a 6 Ω load, the output power for the double three-phase winding and six-phase winding are correspondingly 10.64 and 11.13 kW. In addition, 24 Ω load experiments show that the efficiencies of double three-phase winding and six-phase winding are 96.56% and 98.54%, respectively, verifying the proposed high performance operation.

Single real transformation matrices applied to double three-phase transmission lines

Single real transformation matrices are tested as phase-mode transformation matrices of typical symmetrical systems with double three-phase and two parallel double three-phase transmission lines. These single real transformation matrices are achieved from eigenvector matrices of the mentioned systems and they are based on Clarke's matrix. Using linear combinations of the Clarke's matrix elements, the techniques applied to the single three-phase lines are extended to systems with 6 or 12 phase conductors. For transposed double three-phase lines, phase Z and Y matrices are changed into diagonal matrices in mode domain. Considering non-transposed cases of double three-phase lines, the results are not exact and the error analyses are performed using the exact eigenvalues. In case of two parallel double three-phase lines, the exact single real transformation matrix has not been obtained yet. Searching for this exact matrix, the analyses are based on a single homopolar reference. For all analyses in this paper, the homopolar mode is used as the only homopolar reference for all phase conductors of the studied system.

Fundamental Examination of Hybrid Type Double Three-phase Stepping Motor

In improving the resolution of hybrid type stepping motor, there are a method of increasing the number of rotor teeth and a method of increasing the number of phases. The method of increasing the number of rotor teeth comes for the limit to exist from respect of the machining and the increase in the number of rotor teeth causes the deterioration of high-speed characteristics. On he other hand, the method of increasing the number of phases brings the cost amount from becoming of the drive circuit the complexity.In this paper, aiming at improvement of resolution of HB Type stepping motor, double 3-phase stepping motor are examined which has 2 sets of 3-phase stator windings. It has the half step angle as 3-phase stepping motor with the same number of rotor teeth. It is shown that double 3-phase motor has 2 types of construction which are different in magnetic path (multi-phase magnetic path type and uni-phase magnetic path type). In each type, how to choose the number of rotor teeth and stator magnetic pole intervals to compose double 3-phase stepping motor are examined, and the motor characteristics are compared multi-phase magnetic path type with uni-phase magnetic path type.

Transformer winding selection associated with reconfiguration of existing double circuit line to six-phase operation

Conversion of an existing double circuit three-phase 115 kV overhead transmission line near Binghamton, New York to six-phase operation will provide a commercial demonstration of the feasibility of high phase order power transmission. An important part of this demonstration is specification of the phase/voltage conversion transformers and requirements to permit single pole switching of the line in a practical manner at minimum cost. The results of engineering studies which led to selection of two delta-wye three-phase transformers at each end, one of each pair with reversed polarity to obtain the 60 degrees shift between phases, are presented. >

Optimal Pulse Patterns of Nine-Phase Voltage Source PWM Inverter for Triple Three-Phase Wound AC Motor.

In this work, we successfully applied a six-phase voltage source PWM inverter to a double threephase wound AC motor to attain both an increase in the capacity of the PWM inverter and a reduction in higher harmonics of the phase voltages of the motor. The system uses a coupling reactor, which has the same configuration as that of a three-phase transformer, inserted between the inverter and the motor by means of special windings. This eliminates the need for control to balance output currents from a pair of three-phase inverters. If six-phase voltages are controlled so that there exists no even-number harmonics in the same wave pattern, the coupling reactor concerned absorbs odd-number harmonic voltages other than the orders of 12p±1 (p=1, 2, 3, …). Hence the elimination of these harmonics from the phase voltages of the motor is achieved.It was possible to eliminate the higher harmonics of the phase voltages of the motor most effectively by applying the optimal pulse patterns obtained through the modern theory of control using Lagrange multipliers, resulting in the motor phase voltage patterns being substantially improved.