End Winding Induction Research Articles

Slip Angle Controlled DTC of Open End Winding Induction Motor Drive Using Triple Randomized Decoupled PWM Based Acoustic Noise Mitigation for EV Application

Slip Angle Controlled DTC of Open End Winding Induction Motor Drive Using Triple Randomized Decoupled PWM Based Acoustic Noise Mitigation for EV Application

Enhanced Weighting Factor Eliminated Predictive Torque Control of an Open End Winding Induction Motor Drive

Predictive torque control (PTC) of induction motor drives is one of the best suitable alternatives for direct torque control (DTC). In this article, the weighting factor eliminated PTC for four-level inversion fed open end winding induction motor drive (OEWIMD) has been introduced. The major limitations of classical PTC are as follows: assignment of weighting factor due to dissimilar control objectives, tuning of weighing factors and high computational burden. To circumvent these problems, this article introduces an effective weighting factor elimination-based PTC scheme to an OEWIMD. The proposed algorithm eliminates the complex tuning process of weighting factors by classifying the cost function. The proposed PTC algorithm is simple and provides less computational burden on the controller. In the proposed PTC, the cost function is segregated and ranked accordingly to reduce flux and torque ripples. Cost function-I is formulated to obtain optimum voltage vectors to reduce flux ripples. The same voltage vectors obtained from cost function-I are used in cost function-II to maintain minimum torque ripple. Therefore, the proposed PTC reduces torque and flux ripples with a limited number of voltage vectors and maintains minimum computational burden. The effectiveness of the proposed PTC is verified through MATLAB/SIMULINK and experimentation.

Influence of winding configurations on inductances in 2-pole high-speed permanent magnet machines

Permanent magnet machines often employ two types of winding configurations with conductors located at the left and right sides in a slot, or at the lower and upper layers of a slot. This paper investigates the influence of winding configurations on the inductances in 2-pole high-speed permanent magnet (HSPM) machines, accounting for different coil positions, slot shapes, coil pitches, and slot/pole number combinations. It is found that winding configurations affect the slot leakage inductance depending on the slot shape, in addition to the end-winding inductance which reduces as the increase of coil-pitch. For 2-pole HSPM machines with different slot numbers, the influence of winding configurations on the end-winding inductance decreases with the increase of slot number. Finite element method is used for analyses and the predicted results are validated by experiments on two prototype machines.

Comparative Switching and Conduction Loss Analysis of a SVPWM and DPWM based DTC of Open End Winding Induction Motor Drive

Comparative Switching and Conduction Loss Analysis of a SVPWM and DPWM based DTC of Open End Winding Induction Motor Drive

Calculation of magnetizing and leakage inductances of induction machine using finite element method

Distinguishing between the stator and rotor leakage inductances of induction machines is a challenge, and it becomes more difficult in the case of magnetic saturation that arises in some applications such as self-excited induction generators (SEIG). This paper presents a direct and simple procedure to determine the inductances of induction machines in magnetic saturation region, by combining the experimental tests and finite element modeling of the machine at a synchronous speed. The proposed method uses radial component of the magnetic flux density in air gap to calculate the magnetizing inductance. Also, the stator slot and end-winding leakage inductances are derived by calculating the linkage flux of the stator phases for the three-phase balanced induction machine. The effectiveness of the proposed method is verified by simulation and experimental investigation of SEIG.

Inductance Calculation of Coreless-Type Linear PM Machines Based on Analytical Field Projection and Coil Separation Method

The analysis of winding inductance in electric machinery is crucial for both design and control implementations. This article presents an accurate and computationally efficient method to calculate the winding inductance in a coreless-type permanent magnet linear synchronous machine (PMLSM). The analysis is based on the novel approach combining the analytical field projection and the coil separation method. After dividing the coil domain into three regions, a two-dimensional winding inductance in the front view is calculated by solving the field governing equations in each subdomain. Subsequently, the model is extended in three dimensions by projecting the side view of the coil onto the 2-D plane, and the interpolation method is involved in accounting for the end-winding inductance. As a result, the proposed model can save much computation time to evaluate the winding inductance without relying on the finite element (FE) method. In the end, the validity of the analytical model is verified by FE and experimental results.

Design and Control of Space Vector Pwm Technique with the Fuzzy Control Based Multilevel Inverter for an Open end Winding Induction Motor

In this paper the three phase open end winding IM drive is designed and controlled using a fuzzy control based multilevel inverter with SVM technique is proposed. To overcome the disadvantages of PI controller, in this project we are using the fuzzy controller. The fuzzy controller rules are analyzed very easily, because of it is a human decision making system. The traditional dual inverter having two dc sources the cost and size is might be high, so to overcome this we use the proposed method with single dc voltage source. The main objective of the proposed method is to eliminate the transformer. To achieve the multilevel output voltage waveform with three levels a dc voltage ratio 2:1 is used. The space vector PWM is used to control the switching states of dual multilevel inverter. The fuzzy controller implementation cost is less and more precise. The simulation results are used to analyze the proposed method with fuzzy controller.

Design and Control of Space Vector Pwm Technique with the Fuzzy Control Based Multilevel Inverter for an Open end Winding Induction Motor

Design and Control of Space Vector Pwm Technique with the Fuzzy Control Based Multilevel Inverter for an Open end Winding Induction Motor

Stator Resistance Compensator Based on Model Reference Adaptive System Scheme for Sensor-Less Direct Torque Control of an Open End-Winding Induction Motor with First Coil Faults

Stator Resistance Compensator Based on Model Reference Adaptive System Scheme for Sensor-Less Direct Torque Control of an Open End-Winding Induction Motor with First Coil Faults

Computation of Leakage Inductance of End Coils in Electrical Machines Considering Core Effects

A new analytical method is presented for computing the leakage inductance of the single-end coils of electrical machines, based on the solution of Maxwell’s equations, which considers core eddy currents. Maxwell’s equations are solved in general form in two regions: inside and outside the core, employing appropriate boundary conditions and an iteration scheme. Asymptotic methods are effectively employed for the analytical calculation of Green’s functions in both the regions. Analytical results are compared with 3-D finite-element computations. The comparison shows a close correspondence between the analytical and numerical results. Our formula is the basis for further computations of the end-winding leakage inductance of rotating electric machines.

Different Control Strategies Adopted by Dual Inverter Fed Open End Winding Induction Motor Drive

An open end winding induction motor (OEWIM) drive fed by dual inverter is now being studied for high power application. It is simple in design, operation and it does not have any capacitor balancing issues. A dual inverter circuit can either have an isolated dc sources or a single dc source. Different PWM methods are used to control dual inverter fed OEWIM drive. A review of different control strategies applied for dual inverter fed OEWIM drives are given in this paper.

Study on the End Winding Inductance of Three-Phase Windings in Two Layers

Study on the End Winding Inductance of Three-Phase Windings in Two Layers

Accuracy improvement for complex harmonic analysis modelling of a wound field synchronous generator

Complex harmonic analysis (CHA) provides a computationally efficient alternative to finite element analysis (FEA) for modelling multi-phase wound field synchronous machines. This paper presents three methods that could improve the accuracy of the CHA: by improving the equivalent air gap, by including a saturation factor, and by using image methods for computing end-winding inductance. The comparison against a finite element method and experiment shows the improved complex harmonic method could predict waveforms reliably, where a dynamic finite element method would be time-consuming. This paper shows the method is valid for a five-phase generator.

Enhanced Predictive Torque Control for Open End Winding Induction Motor Drive Without Weighting Factor Assignment

Nowadays, predictive torque control (PTC) is the most popular control technique in the field of electric drives. This PTC strategy is introduced for open end winding induction motor (OEWIM) drive in view of advantages. The conventional PTC offers a single-cost function where torque and stator flux control objectives are present. Since these control objectives are dissimilar, weighting factor designation to the respective control objective is essential. Weighting factor tuning by an empirical approach leads to a cumbersome control process. To overcome this tuning problem, this paper suggests a single control objective containing stator reference and predicted flux space vectors. This simplified proposed control scheme relieves PTC from weighting factor and facilitates combined torque and flux control. However, to control inverter switching frequency including torque and flux in a single cost function, weighting factors assignment and its proper tuning is indispensable. The proposed scheme is extended by replacing a single-cost function with separate multiobjectives and its optimization is achieved using a simple ranking analysis with limited prediction voltage vectors (VVs). This proposed feature permits PTC independent from weighting factors. Simulation and experimentation are performed on a dual inverter fed OEWIM drive. The achieved results are related with conventional PTC to verify the effectiveness of the proposed PTC.

Improvised predictive torque control strategy for an open end winding induction motor drive fed with four‐level inversion using normalised weighted sum model

Open end winding induction motor (OEWIM) drives are better alternate for multi-level inverter fed induction motor drives. OEWIM drives can be used in industries and electric vehicles but they entail ripple-free torque. Predictive torque control (PTC) strategy offers high dynamic performance and lesser ripple in torque, flux when compared with direct torque control. Classical PTC involves high switching frequencies and empirical methods to select weighting factors. The selection and tuning of weighting factors are cumbersome. In this article, a new normalised weighted sum model (WSM) based PTC of four-level inverter fed OEWIM is introduced to curtail torque, flux ripples, switching frequency and enhance the selection of weighting factors. The proposed algorithm uses multi-objective cost function and the optimisation of cost function is performed by using normalised WSM. The normalisation of individual cost function simplifies the selection of weighting factors to select optimal voltage vector. As a result, the proposed PTC offers all the features of classical PTC and overcomes the difficulties involved in classical PTC. Simulation and experimental studies are performed on dual inverter fed OEWIM with four-level inversion. The effectiveness of proposed algorithm is verified by comparing proposed PTC algorithm with classical PTC algorithm.

An Enhanced Three-Level Voltage Switching State Scheme for Direct Torque Controlled Open End Winding Induction Motor

Open End Winding Induction Motors (OEWIM) are popular for electric vehicles, ship propulsion applications due to less DC link voltage. Electric vehicles, ship propulsions require ripple free torque. In this article, an enhanced three-level voltage switching state scheme for direct torque controlled OEWIM drive is implemented to reduce torque and flux ripples. The limitations of conventional Direct Torque Control (DTC) are: possible problems during low speeds and starting, it operates with variable switching frequency due to hysteresis controllers and produces higher torque and flux ripple. The proposed DTC scheme can abate the problems of conventional DTC with an enhanced voltage switching state scheme. The three-level inversion was obtained by operating inverters with equal DC-link voltages and it produces 18 voltage space vectors. These 18 vectors are divided into low and high frequencies of operation based on rotor speed. The hardware results prove the validity of proposed DTC scheme during steady-state and transients. From simulation and experimental results, proposed DTC scheme gives less torque and flux ripples on comparison to two-level DTC. The proposed DTC is implemented using dSPACE DS-1104 control board interface with MATLAB/SIMULINK-RTI model.

An Effective Four-Level Voltage Switching State Algorithm for Direct Torque Controlled Open End Winding Induction Motor Drive by Using Two Two-Level Inverters

This paper introduces an effective four-level voltage switching state algorithm for direct torque controlled open end winding induction motor drive with two-two level inverters in dual mode. In the recent days, direct torque control of open end winding induction motor drive became an interesting area for researchers because it provides high dynamic performance and instantaneous control of stator flux and torque. It is more important especially in applications like propulsion and hybrid electric vehicles they require ripple free torque. The direct torque control provides high flux, torque ripple, and variable switching frequency. This paper introduces an effective voltage switching state algorithm for an open end winding induction motor drive to reduce torque and flux ripple at different frequencies of operation. The experimental results show that the proposed algorithm reduces torque and flux ripples without losing features of conventional direct torque control (DTC) algorithm and in addition it provides multi-level operation.

Performance Improvements in Open End Winding Induction Motor Drive Using Decoupled PWM Techniques

This Paper presents a decoupled space vector modulation algorithm for a three level open-end winding induction motor drive. In the proposed scheme, switching vectors for the 2- two level inverters are generated separately using the instantaneous reference phase voltages along with the simple digital logic. So that, each inverter can be operated as a two level inverter isolately. This modulation scheme does not require any complex computations. This algorithm generates different pulse width modulation (PWM) schemes by phase shifting one inverter phase voltages with respect to the other inverter. A common- mode voltage is identified in the dual inverter, all the PWM schemes presented in this paper mitigating and also eliminating the common-mode voltage (CMV) in a dual inverter. All the pulse width modulation (PWM) schemes generated in the proposed decoupled algorithm are simulated using MATLAB/SIMULINK environment, and the corresponding results are presented.

Simulation of Space Vector Modulation for Open End Winding Induction Motor in PSIM

Simulation of Space Vector Modulation for Open End Winding Induction Motor in PSIM

Calculation Methods and Effects of End-Winding Inductance and Permanent-Magnet End Flux on Performance Prediction of Nonoverlap Winding Permanent-Magnet Machines

Due to the short end windings of nonoverlap winding permanent-magnet (PM) machines, the end-winding inductance component is generally ignored in the design. In most cases, the end-flux fringing effects in PMs are also not taken into account. It is shown in this paper that these end effects have a significant influence on the performance parameters of the machine. In this paper, several nonoverlap winding PM machines are considered with respect to the effects of end-winding inductance and PM end-flux fringing. A number of calculation methods for the per-phase end-winding inductance of the machines are compared. A new simple analytical calculation method is proposed, which is shown to give a relatively good prediction of the end-winding inductance compared with 3-D finite-element (FE) results. It is proposed in this paper that the PM strength should be reduced by a certain fringing factor to take the end-flux fringing effects into account in the 2-D FE analysis. Practical measurements are also presented to validate the FE calculations and to give an indication on the effects that are caused by the end-winding inductance and the PM end-flux fringing.