Design Of Permanent Magnet Synchronous Generator Research Articles

Comparison of Analytical and Numerical Methods for PMSG Design Applied to D-Type Wind Generators

The objective of this work is to perform a comparative study between analytical and numerical methods (implemented via 2-D and 3-D FEM software) in 3.88 MVA, 710 V, 145 Hz permanent magnet synchronous generator (PMSG) design with a focus on wind power generation, for D-Type wind turbines. For this purpose an analytical solving method is proposed using NdFeB surface permanent magnet rotor. After this step the analytical results were compared with the numerical results and showed results with average relative error margin of about 3% (2-D simulation) and average absolute error of 37.3 mT (3-D simulation). In the second part of the design, AlNiCo PM were used in the rotor, however, the analytical and numerical results showed high average error, making the previous method, used for NdFeB PM, not suitable, requiring changes in the method. It is proposed then, a readjustment of the PM volume calculation, through analytical and numerical methodology. For the development of the method the main contributions were the modification of the table of speeds and frequencies from 60 Hz to 145 Hz, the creation of an extension parameter for the tip of the stator tooth to refine the airgap flux density calculation and the analytical solution of the rotor design when using AlNiCo PM. After these changes, the results obtained with a calculated average error margin of about 4% were satisfactory. The analytical and numerical results were commented and presented at the end of this work for the validation of the methodologies for both of PM (NdFeB and AlNiCo).

Electromagnetic Optimal Design of a PMSG Considering Three Objectives and Using NSGA-III

This article presents the optimal design of a permanent magnet synchronous generator (PMSG). A finite element (FE) model is used to construct a metamodel, which afterward is utilized to define the objective function that models the PMSG. Kriging modeling is employed along with the design of experiments based on Latin hypercube sampling. The utilization of a surrogate model allows to speed up the optimization process while keeping the accuracy since they are developed from the FE analysis. On the other hand, it has been reported that the non-sorting genetic algorithm (NSGA) III is better than NSGA-II because it can solve multi- and many-objective optimization problems. This article demonstrates by numerical experiments that NSGA-III can be successfully used in the optimal design of PMSG with three objectives.

Adaptive Damping Design of PMSG Integrated Power System with Virtual Synchronous Generator Control

With the continuous development of wind power capacity, a large number of wind turbines connected by power electronic devices make the system inertia lower, which leads to the problem of system frequency stability degradation. The virtual synchronous generator (VSG) control can make wind turbines possess inertia and damping. However, the stochastic dynamic behavior of wind generation results in the stochastic changing of operating condition; this paper presents an adaptive subsynchronous oscillation (SSO) damping control method for the wind generation with VSG control. Firstly, the small signal model of the permanent magnet synchronous generator (PMSG) with VSG is built, and the model of state space is derived and built. The active power of PMSG is selected as the variable parameter vector to establish a polytopic linear variable parameter system model. Then, based on the hybrid H2/H∞ control method, each vertex state feedback matrix is solved by linear matrix inequality, and a subsynchronous oscillation adaptive damping controller with polytope is obtained. Finally, the 4-machine 2-area system connected to two PMSGs with VSG control is used as the test system for time domain simulation. The simulation results demonstrate that the LPV based adaptive damping controller could provide enough damping under the circumstances of wider changes of wind power outputs.

Design and Analysis of High-Speed Permanent Magnet Synchronous Generator With Rotor Structure Considering Electromechanical Characteristics

In high-speed permanent magnet synchronous generator (PMSG), the rotor design should not only ensure mechanical stability at high speeds but also ensure the required electromagnetic (EM) performance. This paper deals with the EM analysis and design of high-speed PMSGs considering the rotor structure. In particular, the effects of active power and output voltage due to internal impedance from leakage flux are presented. The relationship between design variables of rotor and performance is analyzed using three-dimensional static finite element analysis and simplified equivalent circuit method. Based on the analysis results, a model with improved EM performance using a nonmagnetic pad is presented according to design parameters of rotor structure. The EM performance and the mechanical reliability of the designed model are validated by comparing the FE results with experimental results.

Variable speed PMSG design and implementation for wind driven welding power source

PurposeThe purpose of this paper is the attempt to model a variable speed permanent magnet synchronous generator (PMSG) for extracting a standalone power source to assuage the needs of a welding application. The emphasis orients to evolve a framework for the effective exploration of renewable energy resource and prevent the injection of grid harmonics.Design/methodology/approachThe system involves the use of self-commutated dc-dc converter interfaces to extradite the current and voltage requirements of the welding attributes. The philosophy incites a pulse width formulation for reducing the voltage ripples in the dc output and improving the time response characteristics.FindingsThe proper selection of closed loop Fuzzy tuned PI control ensures the restriction on the magnitude of the current drawn from the source, enhances the dynamic response and betters steady state response.Originality/valuePMSG-based welding power source with parallel-connected cascaded buck fed cuk converters. MATLAB-based simulation of the methodology offer interesting results in the sense it orchestrates the range of converter operation and the ability to provide a high-quality weld without polluting the ac mains. The experimental prototype further proliferates to validate the simulated performance and claims a space for its use in the real-world utilities.

Conceptual Framework of Antecedents to Trends on Permanent Magnet Synchronous Generators for Wind Energy Conversion Systems

Wind Energy Conversion System (WECS) plays an inevitable role across the world. WECS consist of many components and equipment’s such as turbines, hub assembly, yaw mechanism, electrical machines; power electronics based power conditioning units, protection devices, rotor, blades, main shaft, gear-box, mainframe, transmission systems and etc. These machinery and devices technologies have been developed on gradually and steadily. The electrical machine used to convert mechanical rotational energy into electrical energy is the core of any WECS. Many electrical machines (generator) has been used in WECS, among the generators the Permanent Magnet Synchronous Generators (PMSGs) have gained special focus, been connected with wind farms to become the most desirable due to its enhanced efficiency in power conversion from wind energy turbine. This article provides a review of literatures and highlights the updates, progresses, and revolutionary trends observed in WECS-based PMSGs. The study also compares the geared and direct-driven conversion systems. Further, the classifications of electrical machines that are utilized in WECS are also discussed. The literature review covers the analysis of design aspects by taking various topologies of PMSGs into consideration. In the final sections, the PMSGs are reviewed and compared for further investigations. This review article predominantly emphasizes the conceptual framework that shed insights on the research challenges present in conducting the proposed works such as analysis, suitability, design, and control of PMSGs for WECS.

Detailed Design Procedures for PMSG Direct-Driven by Wind Turbines

This paper is committed to show a well-ordered system used to design a permanent magnet synchronous generator (PMSG). The fundamental focus of this work is the generators which are in gearless configuration, and in the fragmentary or couple of kilowatts power range. A straight lumped-component based model is introduced, which is utilized for fundamental investigation and design. Later, a proposed comprehensive design strategy—stated with conditions, tables, design limits and practical recommendations—are presented in full details. Likewise, a flowchart is created to be later used as a Matlab M-File code for PMSG design. The outlined strategies are then authenticated through three case studies while being compared to the result from Finite Element Method (FEM) of Maxwell package. The three case studies are firstly, comparing the effectiveness of the procedures with a PMSG presented in literature. Secondly compared to a generator from the market. And finally using the procedure to implement a 1 kw prototype generator and validate the results with it. Such comparisons have validated the proposed procedures as a contributed step-by-step simple and reliable design tool for such cluster of PMSGs.

Cogging Torque Reduction Based on a New Pre-Slot Technique for a Small Wind Generator

Cogging torque is a pulsating, parasitic, and undesired torque ripple intrinsic of the design of a permanent magnet synchronous generator (PMSG), which should be minimized due to its adverse effects: vibration and noise. In addition, as aerodynamic power is low during start-up at low wind speeds in small wind energy systems, the cogging torque must be as low as possible to achieve a low cut-in speed. A novel mitigation technique using compound pre-slotting, based on a combination of magnetic and non-magnetic materials, is investigated. The finite element technique is used to calculate the cogging torque of a real PMSG design for a small wind turbine, with and without using compound pre-slotting. The results show that cogging torque can be reduced by a factor of 48% with this technique, while avoiding the main drawback of the conventional closed slot technique: the reduction of induced voltage due to leakage flux between stator teeth. Furthermore, through a combination of pre-slotting and other cogging torque optimization techniques, cogging torque can be reduced by 84% for a given design.

Exploration of a Permanent Magnet Synchronous Generator with Compensated Reactance Windings in Parallel Rod Configuration

In this study, a permanent magnet synchronous generator (PMSG) topology with compensated reactance windings in parallel rod configuration is proposed to reduce the armature reactance XL and to achieve higher efficiency of PMSG. The PMSG was designed using iron-cored bifilar coil topology to overcome problems of market-dominant rotary type generators. Often the problem is a comparatively high armature reactance XL, which is usually bigger than armature resistance Ra. Therefore, the topology is proposed to partially compensate or negligibly reduce the PMSG reactance. The study was performed by using finite element method (FEM) analysis and experimental investigation. FEM analysis was used to investigate magnetic field flux distribution and density in PMSG. The PMSG experimental analyses of no-load losses and electromotive force versus frequency (i.e., speed) was performed. Also terminal voltage, power output and efficiency relation with load current at different frequencies have been evaluated. The reactance of PMSG has low value and a linear relation with operating frequency. The low reactance gives a small variation of efficiency (from 90% to 95%) in a wide range of load (from 3 A to 10 A) and operation frequency (from 44 Hz to 114 Hz). The comparison of PMSG characteristics with parallel and series winding connection showed insignificant power variation. The research results showed that compensated reactance winding in parallel rod configuration in PMSG design provides lower reactance and therefore, higher efficiency under wider load and frequency variation.

DESIGN AND OPTIMIZATION OF PERMANENT MAGNET SYNCHRONOUS GENERATOR FOR USE IN HYDRODYNAMIC RENEWABLE ENERGY BY APPLYING ACO AND FEA

One of the most important ways to reduce fossil fuel consumption and consequently reduce greenhouse gases and environmental pollution is the use of renewable energies such as water, sun, wind, etc. One of the most efficient ways to take advantages of the shallow flowing waters such as rivers and fountains in electrical power generation is the use of hydrodynamic screw in the direction of water flow. The design of the generator for this application results in environmental dangers decrease. On the other hand, it provides some part of electrical energy required for human beings. Generators in hydrodynamic renewable energy system ought to have features such as high efficiency, power density and reliability as well as low volume. Among various generators, the permanent magnet synchronous generator (PMSG) meets these requirements very well. In this paper, first, analytical calculations and the design process of PMSG were explained. Then, the ant colony optimization (ACO) was used for the optimization of design quantities. PMSG design optimization increased in efficiency and decreased in volume. By improving these two parameters in the designed PMSG, it gets very suitable to be used in hydrodynamic renewable energy system. Finally, the results of the optimized design of PMSG were validated through simulation of it in Maxwell software and applying finite element analysis (FEA). Also the final results have been compared to similar experimental researches results.

Wide speed range permanent magnet synchronous generator design for a DC power system

A wide speed range permanent magnet synchronous generator (PMSG) system is studied in this paper, including the PMSG design and comparative study on control strategies with a pulse width modulation (PWM) rectifier, the purpose of which is to regulate the DC-link voltage. It is of great importance to study the foregoing DC power system based on the PMSG and PWM rectifier, where vector control (VC) can be implemented and the corresponding field-weakening strategy can be realized by injecting a field-weakening current component without any auxiliary devices. Large machine inductance is desired in order to limit the short-circuit current and the loaded voltage drop. Different control strategies including VC, direct torque control (DTC) and direct voltage control (DVC) are studied and compared with both simulations and experiments.

Permanent magnet synchronous generator design solution for large direct-drive wind turbines: Thermal behavior of the LC DD-PMSG

Wind is one of the most compelling forms of indirect solar energy. Available now, the conversion of wind power into electricity is and will continue to be an important element of energy self-sufficiency planning. This paper is one in a series intended to report on the development of a new type of generator for wind energy; a compact, high-power, direct-drive permanent magnet synchronous generator (DD-PMSG) that uses direct liquid cooling (LC) of the stator windings to manage Joule heating losses. The main parameters of the subject LC DD-PMSG are 8 MW, 3.3 kV, and 11 Hz. The stator winding is cooled directly by deionized water, which flows through the continuous hollow conductor of each stator tooth-coil winding. The design of the machine is to a large degree subordinate to the use of these solid-copper tooth-coils. Both steady-state and time-dependent temperature distributions for LC DD-PMSG were examined with calculations based on a lumped-parameter thermal model, which makes it possible to account for uneven heat loss distribution in the stator conductors and the conductor cooling system. Transient calculations reveal the copper winding temperature distribution for an example duty cycle during variable-speed wind turbine operation. The cooling performance of the liquid cooled tooth-coil design was predicted via finite element analysis. An instrumented cooling loop featuring a pair of LC tooth-coils embedded in a lamination stack was built and laboratory tested to verify the analytical model. Predicted and measured results were in agreement, confirming the predicted satisfactory operation of the LC DD-PMSG cooling technology approach as a whole.

Two‐dimensional finite element magnetostatic model of a permanent magnet synchronous generator for predicting its steady‐state performance under different loading conditions

A new two-dimensional magnetostatic finite element (FE) model for predicting the steady-state performance of a permanent magnet synchronous generator (PMSG) is proposed. A PMSG can be found in wind farms and emergency electrical power plants. A FE model to predict the PMSG steady-state operation is valuable for initialisation of transient studies and for PMSG design evaluation. In the proposed FE model, the unknowns to be determined are the magnetic vector potential, load angle, stator phase currents and terminal voltage. The model formulation allows the simultaneous computation of the magnetic field, load angle and terminal current of the PMSG. Frequency and load are considered as the model input data. The FE model is validated against experimental tests and a good agreement is obtained.

The Electromagnetic Field Analysis of Permanent Magnet Synchronous Generator Based on ANSYS

This paper uses ANSYS 10.0 software to analyze and calculate electromagnetic field of the Permanent Magnet Synchronous Generator(PMSG). Verify rationality of magnetic circuit by the results of magnetic flux density and magnetic field intensity; optimize shape of permanent magnet and reduce harmonics quantity by air-gap flux density harmonics analysis, and use value to solve Electromotive Force(EMF). The simulation result proves that the model satisfies the design requirements and can provide theoretical guide for the optimization design of PMSG.