Six-phase Induction Motor Research Articles

Current Gradient Based Modified Hysteresis Controller for Asymmetrical Six-Phase Induction Motor

Current Gradient Based Modified Hysteresis Controller for Asymmetrical Six-Phase Induction Motor

Hysteresis Current Control for Six-Phase Induction Motor Drives With Reduced Ripple and Improved Tracking Based on Subspace Decomposition and Restrained Voltage Vectors

Hysteresis Current Control for Six-Phase Induction Motor Drives With Reduced Ripple and Improved Tracking Based on Subspace Decomposition and Restrained Voltage Vectors

Stator Faults Diagnostics in Symmetrical Six-Phase Induction Motors Fed by a Three-Phase System

Stator Faults Diagnostics in Symmetrical Six-Phase Induction Motors Fed by a Three-Phase System

SUIVI DU POINT DE PUISSANCE MAXIMUM DANS UN SYSTÈME DE POMPAGE SOLAIRE PEROVSKITE AVEC UN MOTEUR À INDUCTION SIX PHASE

In this work, the maximum power point (MPP) of a photovoltaic (PV) array utilized as a source of electricity in standalone mode is tracked using a genetic algorithm (GA) as an optimization tool. The major objective of this work is to implement and regulate a six-phase induction motor (SPIM) powered by a centrifugal pump and fed by a perovskite solar array through a three-phase inverter. Perovskite solar cells are the most promising third-generation photovoltaic technology to replace silicon-based photovoltaic. These cells are made cheaply, at a low temperature, and efficiently. The outcomes are then investigated utilizing a SPIM scaler (v/f) closed-loop control. PID controllers are tuned to keep the motor speed aligned with the reference value. The transformer's six-phase secondary is linked to an LC filter to reduce the voltage and current waveform ripple. A test setup was created and installed to investigate the potential of controlling the SPIM fed via a three-to-six-phase transformer. The findings showed that the area needed for the plates when utilizing perovskite solar cells is just 14 % of what it would be if a silicon-based solar array were used for the identical purpose. Perovskite solar cells' tiny surface area helps to prevent partial shading and lower costs. It was discovered that the suggested method works well for powering SPIM from a three-phase source.

Novel SV-PWM Strategies for Six-Phase Induction Motor Drive With Reduced Switching Losses and Common-Mode Voltage

Novel SV-PWM Strategies for Six-Phase Induction Motor Drive With Reduced Switching Losses and Common-Mode Voltage

Space Vector-Based Hysteresis Current Controller of Asymmetrical Six-Phase Induction Motor

Space Vector-Based Hysteresis Current Controller of Asymmetrical Six-Phase Induction Motor

Fractional Order Transfer Function Identification of Six-Phase Induction Motor Using Dual-Chirp Signal

Fractional Order Transfer Function Identification of Six-Phase Induction Motor Using Dual-Chirp Signal

Simple Predictive Current Control of Asymmetrical Six-Phase Induction Motor With Improved Performance

Despite the intensive research work on the application of model predictive control (MPC) for multi-phase machines, there are many challenges still to be handled such as high circulating currents, variable switching frequency, and high computation burden. This paper proposes a simple, yet efficient predictive current control (PCC) for six-phase induction motor (IM) that reduces considerably circulating current, computation cost, and switching frequency. In the proposed method, a group of four candidate voltage vectors (VVs) is formed in each control sample. Unlike similar methods reported in literature, these candidate vectors are generated based on a simple lookup table and the previous optimal VV. The lookup table is designed such that it allows only one commutation in each control sample. The performance of the proposed method is assessed experimentally using a one kW asymmetrical six-phase induction motor (A6PIM). Different performance indices are investigated to compare the proposed method against two different PCC methods in literature at different operating conditions. The experimental results confirm that about 50% reduction in average switching frequency and 15% in current total harmonic distortion at different speed ranges are observed with the proposed method compared to the conventional one.

Continuous-Control-Set Model Predictive Current Control of Asymmetrical Six- Phase Drives Considering System Nonidealities

Finite-control-set model predictive control (FCS-MPC) of multiphase ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> -phase, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> is assumed to be an odd number for simplicity) drives is challenging because of the large number of actual/virtual voltage vectors and the need for current control in ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> -1)/2 sub-spaces (or planes; multi-plane current control). Any sub-optimal design (poor or no current control in some of the ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> -1)/2 planes) may result in high individual plane current ripples, due to the low reactance. This work therefore investigates continuous-control-set (CCS) MPC for constant switching frequency multiphase motor drives as another alternative. The high-bandwidth CCS-MPC is designed to accurately account for system non-idealities, namely digital control and pulse width modulation delays, inverter dead time, and measurement noise. It will be shown that the CCS-MPC has the advantages of full voltage vector space access, regular switching characteristic, and improved cycle-by-cycle tracking control, while maintaining some of the known advantages of the FCS-MPC, e.g., intuitive cost function design, model-based control, and fast dynamics. The proposed control scheme is benchmarked experimentally against the classical, proportional-integral-based, field-oriented control in conjunction with an asymmetrical six-phase induction motor drive.

Online Diagnosis and Discrimination of Stator Faults in Six-Phase Induction Motors Based on Voltage Symmetrical Components

In recent years, multiphase machines have been presented as a good alternative to the classical three-phase machines, mainly due to their ability to operate smoothly under fault conditions. Due to multiple stator phase arrangements, existing fault diagnostic (FD) methods are not sufficiently universal and cannot be applied to the multiple configurations of multiphase machines. In this regard, the current research proposes a universal and effective online diagnostics technique based on the computation and monitoring of a relevant severity factor, which is defined as the ratio of the zero, negative and positive voltage symmetrical components. The Short Time Least Square Prony’s (STLSP) approach is used to implement this method online in LabVIEW environment. In addition to the wide applicability of the method, the obviation of any motor parameter estimation and limited requirements regarding variables measurements make the proposed approach extremely advantageous for motors with high number of phases. This article addresses at stator faults in symmetrical six-phase induction machines (6PIM). The proposed method’s experimental results on six-phase motor drive platforms demonstrate the excellent generalization capability of the proposed method, as well as high accuracy and robustness, along with the ability to accurately distinguish between the occurrence of Inter-Turn Short Circuit (ITSC) faults and the presence of Unbalance Supply Voltage (USV) conditions. A 6PIM is put through its paces in both healthy and faulty conditions. The obtained results demonstrate the effectiveness of the proposed method for diagnosing the occurrence of ITSC faults and USV operating conditions with high reliability, fastness and high precision.

DC-Signal Injection for Stator-Resistance Estimation in Symmetrical Six-Phase Induction Motors Under Open-Phase Fault

Multiphase machines are often chosen due to their enhanced fault tolerance. Six-phase ones are especially convenient because they may be fed by off-the-shelf three-phase converters. In particular, those with symmetrical windings offer superior postfault capabilities. On the other hand, estimation of the stator resistance is important for purposes such as thermal monitoring and preserving control performance. Resistance estimation by dc-signal injection provides low sensitivity to parameter deviations compared with other techniques. It has previously been shown that the dc signal can be added in the non-torque-producing (<inline-formula><tex-math notation="LaTeX">$x$</tex-math></inline-formula>-<inline-formula><tex-math notation="LaTeX">$y$</tex-math></inline-formula>) plane of a six-phase machine to avoid the torque disturbances that typically arise in three-phase machines. However, extending this method to the case of an open-phase fault (OPF) is not straightforward, because of the associated current restrictions. This paper addresses dc-signal injection in a symmetrical six-phase induction motor with an OPF. It is shown that, in contrast to healthy operation, the postfault dc injection should be carefully performed so that minimum copper loss, peak phase current and zero-sequence braking torque are achieved. A solution that attains optimum performance in all these aspects simultaneously is proposed. Adapted controller and resistance estimation are also presented. Experimental results confirm the theory.

Stator Faults Detection in Asymmetrical Six-Phase Induction Motor Drives with Single and Dual Isolated Neutral Point, Adopting a Model Predictive Controller

Multiphase drives have been presented as potential replacements for conventional three-phase machines, primarily because of their propensity to operate faultlessly. Due to the various stator phase arrangements, standard fault detection techniques are insufficiently applicable and cannot be used to diagnose faults in the various configurations of multiphase machines in closed-loop applications. The current study proposes an effective online diagnostic technique based on the computing and tracking of a significant severity factor, which is defined as the ratio of the zero, negative, and positive voltage symmetrical components employing a short-time least-square Prony algorithm (STLSP). In this study, the asymmetrical six-phase induction motor (ASPIM) was controlled by a model predictive control (MPC) algorithm, an attractive control scheme for the regulation of multiphase electric drives, since it easily exploits their inherent advantages. This article addresses stator faults in ASPIMs. The effectiveness of the suggested strategy was confirmed experimentally for various operating conditions in both steady and transient states.

Enhanced Reaching-Law-Based Discrete-Time Terminal Sliding Mode Current Control of a Six-Phase Induction Motor

This paper develops an inner stator current controller based on an enhanced reaching-law-based discrete-time terminal sliding mode. The problem of tracking stator currents with high accuracy while ensuring the robustness of a six-phase induction motor in the presence of uncertain electrical parameters and unmeasurable states is tackled. The unknown dynamics are approximated by using a time delay estimation method. Then, an enhanced power-reaching law is used to make each stage of the convergence faster. A stability analysis and the system controller’s finite-time convergence are demonstrated in detail. Practical work was conducted on an asymmetrical six-phase induction machine to illustrate the developed discrete approach’s robustness and effectiveness.

A 5-level T-type inverter fed six-phase induction motor drive for industrial applications

ABSTRACT This paper presents the performance analysis of a five-level T-type multilevel inverter (MLI) based six-phase induction motor drive (SPIMD) for high-power industrial applications. In the adopted T-type MLI, the sensorless self-capacitor voltage balancing control is designed, which controls the voltage across the capacitor at half the magnitude of the direct current (DC) source value, creating a symmetrical five-level output voltage waveform. Moreover, self-capacitor voltage balancing control reduces complexity and improves system performance. The SPIMD with distributed neutral is taken as the load, and the whole system is simulated using MATLAB/Simulink software. The system’s performance is determined by considering the power loss and efficiency. This paper also presents a comparative performance analysis of the adopted T-type, cascaded h-bridge (CHB) and Flying Capacitor (FC) MLI-based SPIMD. Finally, a prototype is developed as a proof of concept and tested experimentally to validate the analytical development of the adopted system.

Analysis of the Drive of the Electric Vehicle with Six-Phase Induction Motor

Abstract The article presents the analysis of the drive system of the electric vehicle with a six-phase induction motor. The mathematical models of the six-phase induction motor and model reference adaptive system (MRASF) estimator are presented, and the description of the voltage source inverter, space vector modulator and bidirectional buck–boost converter is shown. The direct field-oriented control (DFOC) system and the direct torque control with space vector modulation (DTC-SVM) system are analysed. Results of simulation studies of these control methods and comparative analysis are shown. The DTC-SVM method is selected as the method with the best properties, and a full model of the electric vehicle drive system is built using this method. The detailed description of the drive system of the electric vehicle with a six-phase induction motor and DTC-SVM control system and the results of simulation tests for this drive system are presented. The aim of the authors and an element of novelty is to develop and test a drive system for an electric vehicle with a six-phase induction motor, adaptive speed estimator and extensive space vector modulator.

An Integrated Strategy for the Real-Time Detection and Discrimination of Stator Inter-Turn Short-Circuits and Converter Faults in Asymmetrical Six-Phase Induction Motors

An Integrated Strategy for the Real-Time Detection and Discrimination of Stator Inter-Turn Short-Circuits and Converter Faults in Asymmetrical Six-Phase Induction Motors

A Simplified Model Predictive Control for Asymmetrical Six-Phase Induction Motors That Eliminates the Weighting Factor

The conventional model predictive control (MPC) is an attractive control scheme for the regulation of multiphase electric drives, since it easily exploits their inherent advantages. However, as the number of phases increases, the MPC’s complexity increases exponentially, posing a high computational burden. Additionally, the MPC still presents other issues related to the weighting factor design in the cost function. Accordingly, this paper proposes a low-complexity hysteresis model predictive current control (HMPCC) that can significantly reduce the computational burden, improve the motor’s performance, and completely avoid the weighting factor design. The proposed method is a hybrid control method, consisting of two distinct controls that complement one another. The hysteresis control is used to reduce the number of iterations per sampling period, thereby reducing the computational effort required to choose the voltage vector that actively produces torque/flux, and nullifying the weighting factor requirement. Finally, the MPC is used to improve the torque and current quality. The effectiveness of the proposed method is verified through experimental data, and the results emphasize the improvement of the proposed HMPCC scheme.

Novel Method for Instantaneous Neutral Point Voltage Balancing for a Stacked Multilevel Inverter-Fed Six-Phase Induction Motor Drives

This article proposes a novel method for instantaneous neutral point (NP) balancing for a six-phase stacked multilevel inverter (MLI)-fed induction motor (IM) drive. A stacked inverter requires as many dc sources as the number of stackings. A single dc source is ensured with instantaneous NP balancing although there are two stackings of MLIs. A single dc-link enables direct back-to-back power conversion and power can be fed back to mains at the desired power factor. Instantaneous NP balancing is achieved by ensuring that at any instant, no midpoint current is drawn from the NP (dc-link capacitor midpoint). This work shows that the midpoint is used only as a tapping point to generate the different pole voltage levels and no current needs to be drawn from it. V/f experiment is conducted on a six-phase IM with a nine-level stacked MLI, which is developed by stacking two five-level inverters where each of the five-level is developed by cascading a flying capacitor with a capacitor fed cascaded H-bridge. The results ensured that the proposed method for zero instantaneous NP current is valid for both steady-state and transient conditions of a six-phase IM drive using stacked MLI.

A Comparative Study of Fuzzy SMC with Adaptive Fuzzy PID for Sensorless Speed Control of Six-Phase Induction Motor

Multi-phase motors have recently replaced three-phase induction motors in a variety of applications due to the numerous benefits they provide, and the absence of speed sensors promotes induction motors with variable speed drives. Sensorless speed control minimizes unnecessary speed encoder cost, reduces maintenance, and improves the motor drive’s reliability. The performance comparison of the fuzzy sliding mode controller (FSMC) with adaptive fuzzy proportional integral derivative (AFPID) control methods for sensorless speed control of six-phase induction motors was analyzed in this study, and the proposed control system has an advantage for multiphase machines, specifically six-phase induction motors (IMs) in this study, as they are the current active research area for electric vehicles, hybrid electric vehicles, aerospace, ship propulsion, and high-power applications. The speed control of a six-phase induction motor was performed by using an AFPID controller and FSMC. The comparative performance analysis was based on sensorless speed control of the six-phase induction motor. A proportional integral derivative (PID) controller is commonly employed as it is used to eliminate oscillations, but it has several drawbacks, such as taking a long time to decrease the error and stabilize the system at constant speed. The fuzzy type-2 and PID controllers were hybridized so as to obtain the advantages of both to enhance the system performance. Finally, the comparison result revealed that the FSMC preforms significantly better by achieving good tracking performance. The control technique maintains the sliding mode approach’s robustness while providing reduced overshoots with a smooth control action, and the FSMC revealed good dynamic response under load variations when compared to the AFPID controller.

Speed Estimation of Six-Phase Induction Motors, Using the Rotor Slot Harmonics.

Multiphase machines have recently been promoted as a viable alternative to traditional three-phase machines. Most experts are looking for strategies to estimate the rotation speed of such complex systems, since speed data are required for high-performance control purposes. Traditionally, electromechanical sensors were used to detect the rotor speed of electric motors. These devices are extremely accurate, but they are also delicate and costly to deploy. New speed estimating algorithms must be created for these situations. This paper looks at how to estimate rotor speed in symmetrical six-phase induction motors (IMs) using a novel strategy for rotor speed estimation based on the Short Time Fourier Transform (STFT) method. The technique is based on tracking the frequencies of the rotor slot harmonics (RSH) seen in most squirrel-cage IM stator currents, thus assuring a broad range of applications. To monitor the RSH, the STFT employs a sliding window to perform the discrete Fourier transform technique, making it more suitable for online use with noisy and nonstationary signals. Experimental tests demonstrate the effectiveness of the suggested approach.