Permanent Magnet Induction Generator Research Articles

A survey on a novel double-rotor spoke-type permanent magnet induction generator employing bridged and bridgeless structures

A survey on a novel double-rotor spoke-type permanent magnet induction generator employing bridged and bridgeless structures

Energy Storage System with Dynamic Voltage Restorer Integrated For Wind Energy System

The permanent magnet induction generator (PMSG) based wind system that integrates with dynamic voltage restorer (DVR) and the energy storage system (ESS) for backup power purpose is explained in this paper. The output power transmission of the wind energy generation is interfaced with the dynamic voltage restorer in series. The energy storage system and the dc-link capacitor are parallel to the PMSG based wind system. The proposed system is to control the fluctuations in wind power and compensate the disturbed grid voltages. The bidirectional converter controls the power flow in both directions as the power flow from the source to battery and battery to the voltage source inverter (VSI) compensates the grid voltage disturbances through the voltage injection performance and transformer. The DVR-based energy storage system results for the wind energy conversion system are validated using in MATLAB/Simulink.

Automatic reactive power control of isolated wind–diesel hybrid power system using artificial bee colony and gray wolf optimization

ABSTRACTThis paper investigates the artificial bee colony (ABC)- and gray wolf optimization (GWO)-based robust controllers in an isolated winddiesel hybrid power system (IWDHPS). The IWDHPS comprises a wind energy conversion system (WECS) and a diesel engine set. A permanent-magnet induction generator and a synchronous generator are used for power generation with WECS and diesel engine set, respectively. The voltage fluctuations at the generator terminal occur because of the mismatch between generated and consumed reactive power in the system, which further causes a reduction in the quality and stability of the power supply. An automatic voltage regulator (AVR) and a static synchronous compensator (STATCOM) are utilized to suppress these voltage fluctuations in the considered system. Both AVR and STATCOM are equipped with proportional integral (PI) controllers with a single input. The performance and robustness conditions of the control system are expressed as the optimization problem based on the H loop shaping. The ABC and GWO algorithms are applied to solve the optimization problem and to achieve the values of PI controllers for AVR and STATCOM simultaneously. The proposed controller performance is compared with the performance of the bacterial foraging optimization algorithm, particle swarm optimization algorithm, genetic algorithm, and conventional based controller, for the same IWDHPS.

Firefly Optimization Algorithm for the Reactive Power Control of an Isolated Wind-Diesel System

This paper investigates the application of firefly optimization algorithm to design an optimal control for voltage stability of a stand-alone hybrid renewable generation unit based on reactive power control. The studied renewable generation unit mainly consists of a permanent magnet induction generator driven by wind turbine and a synchronous generator driven by diesel engine. A STATCOM is used to stabilize the terminal load bus voltage via compensating of reactive power. The main control objective aims to stabilize the terminal load voltage against any disturbances in load reactive power and/or input wind power by adjusting the total system reactive power. This is accomplished by controlling STATCOM phase angle and hence to control the load bus voltage and also by controlling the excitation voltage of the synchronous generator. The proposed renewable energy power system based on the proposed optimal controller has been tested through step change in input wind power and load reactive power. The system performance based on the proposed control is compared with model predictive control, a robust H∞ control, and a classical PI control.

Optimal controllers designs for automatic reactive power control in an isolated wind-diesel hybrid power system

The paper presents the bacterial foraging optimization algorithm (BFOA) and particle swarm optimization (PSO) algorithm based robust controllers for voltage deviations due to the variation of reactive power in an isolated wind-diesel hybrid power system. The isolated wind-diesel system consists of wind energy conversion system (WECS) utilizing a permanent magnet induction generator (PMIG). Further, a synchronous generator (SG) is used with the diesel engine set for power generation. The mismatch between generated and consumed reactive power in the system causes voltage fluctuations, which will occur at generator terminals. These oscillations further causes reduction in the stability and quality of the power supply. The static synchronous compensator (STATCOM) and an automatic voltage regulator (AVR) are used to suppress voltage fluctuations in an isolated wind-diesel hybrid power system. The STATCOM is used as a reactive power compensator and the AVR is used to keep the terminal voltage constant for the synchronous generator. Both STATCOM and AVR are having proportional and integral (PI) controllers with single input. In modeling for the system, a normalized co-prime factorization is applied to show the possible unstructured uncertainties in the power system such as variation of system parameters and generating and loading conditions. The performance and robust stability conditions of the control system are formulated as the optimization problem, which is based on the Hα loop shaping. BFOA and PSO algorithms are implemented to solve this optimization problem and to achieve PI control parameters of STATCOM and AVR simultaneously. In order to show the efficiency of the proposed controllers, the performance of the proposed controllers is compared with the performance of the conventional controller and genetic algorithm (GA) based PI controllers for the same wind-diesel system. The dynamic responses of the system for four different small-disturbance case studies has been carried out in MATLAB environment.

Modeling of Self-Excited Isolated Permanent Magnet Induction Generator Using Iterative Numerical Method

Self-Excited Permanent Magnet Induction Generator (PMIG) is commonly used in wind energy generation systems. The difficulty of Self-Excited Permanent Magnet Induction Generator (SEPMIG) modeling is the circuit parameters of the generator vary at each load conditions due to the a change in the frequency and stator voltage. The paper introduces a new modeling for SEPMIG using Gauss-sidle relaxation method. The SEPMIG characteristics using the proposed method are studied at different load conditions according to the wind speed variation, load impedance changes and different shunted capacitor values. The system modeling is investigated due to the magnetizing current variation, the efficiency variation, the power variation and power factor variation. The proposed modeling system satisfies high degree of simplicity and accuracy.

An emulator for fixed pitch wind turbine studies

A wind turbine emulator is an important hardware to simulate wind energy conversion systems. The emulator hardware is often built by a coupled motor as prime mover and controlled by a variable speed drive to the shaft of an electrical generator. In this work, we propose, design and implement a novel wind turbine emulator by using a squirrel cage induction machine and permanent magnet induction generator. The control of the prime mover is performed by an IGBT AC drive. The drive itself is controlled by a 32-bit microprocessor. Furthermore, the computer supervises the drive and generates the wind patterns and sets the configuration of wind turbine models. This allows the user to define different wind patterns and to emulate different wind turbines. The combination of the PI controller, the computer supervision, and the microprocessor ensures an accurate performance of entire system. The frequency of the generated voltage is proportional to the shaft rotational speed. Therefore, the output voltage frequency is used as a rotational speed meter. RS-485 is the main communication channel between the drive and the computer. Finally, the results demonstrate the effective and accurate performance of the proposed emulator in reproducing the dynamics of an actual wind turbine.

Dynamic stability study of an isolated wind-diesel hybrid power system with wind power generation using IG, PMIG and PMSG: A comparison

This paper presents a comparative study of reactive power control for isolated wind-diesel hybrid power system in three different cases with wind power generation by induction generator (IG), permanent-magnet induction generator (PMIG) and permanent-magnet synchronous generator. The synchronous generator (SG) is used with diesel engine set. A mathematical model of the system based on small signal analysis, is developed considering reactive power flow balance equations. The variable reactive power needed by the system is provided by a static synchronous compensator (STATCOM) when wind power generation is done by IG and PMIG. When permanent-magnet synchronous generator (PMSG) is used for wind power generation, the variable reactive power demand is fulfilled by a voltage source converter (VSC) which is on the load side. A new mathematical approximation model for VSC connected with PMSG is proposed such that the voltage source converter fulfills the increased reactive power requirement of load and also increases its active power equal to the increased input wind power. Proportional and integral (PI) gains of the STATCOM and VSC controllers are optimized using integral square error criterion (ISE). The dynamic responses of the system for small (1%) step increase in load reactive power with and without 1% step increase in input wind power are shown. The paper also shows the dynamic responses of the system for random step change in load reactive power plus random step change in input wind power. The MATLAB/SIMULINK environment is used for simulation.

Performance Investigation of Isolated Wind–Diesel Hybrid Power Systems With WECS Having PMIG

This paper presents the automatic reactive power control of isolated wind-diesel hybrid power systems having a permanent-magnet induction generator for a wind energy conversion system and a synchronous generator for a diesel generator set. To minimize the gap between reactive power generation and demand, a variable source of reactive power is used such as a static synchronous compensator. The mathematical model of the system used for simulation is based on small-signal analysis. Three examples of the wind-diesel hybrid power system are considered with different wind power generation capacities to study the effect of the wind power generation on the system performance. This paper also shows the dynamic performance of the hybrid system with and without change in input wind power plus 1% step increase in reactive power load.

Finite Element Analysis of Permanent Magnet Induction Generator

Many reliable energy conversion methods are constantly being sought for renewable energy applications. The permanent magnet induction generator is a new concept which uses permanent magnets to provide the flux in the machine. This will lead to an improved power factor and higher efficiency. This type of generator is a very attractive renewable solution. In this paper ,firstly,introduce the structure and principle of permanent magnet induction generator. Secondly, the dynamic starting performance of this machine is studied. Finally, finite element analysis and simulation are carried out, the results verify the performance of the machine meet the design requirements.

Design of New Concept Direct Grid-Connected Slip-Synchronous Permanent-Magnet Wind Generator

This paper deals with the modeling, the design, and the construction of a new concept slip-synchronous permanent-magnet (PM) wind generator for direct-drive direct grid connection. This generator is a variation of the conventional PM induction generator concept as proposed and analyzed in literature. The use of nonoverlap windings is proposed for the first time for this type of generator. Combined analytical and finite-element calculation and design-optimization methods are developed and used in the design of the generator. Load torque ripple and no-load cogging torque are identified as very important design parameters and are minimized to an absolute minimum in the design optimization. The modeling and the design are verified with measurements on a 15-kW prototype wind generator system.

Study of an isolated wind–diesel hybrid power system with STATCOM by incorporating a new mathematical model of PMIG

SUMMARYThis paper presents automatic reactive power control of an isolated wind–diesel hybrid power system. A synchronous generator is used for power generation from diesel and a permanent‐magnet induction generator (PMIG) is used for electric power generation from wind turbine. A new mathematical model is developed to incorporate the effect of permanent‐magnet of the PMIG in the generation of reactive power. To eliminate the gap between reactive power generation and demand, a variable source of reactive power is used such as static synchronous compensator (STATCOM). A study on the wind–diesel system is conducted based on small signal analysis by considering IEEE type‐1 excitation system for the synchronous generator. The paper also shows the dynamic performance of the hybrid system both for constant and variable slip conditions and 1% step change in reactive power load. Copyright © 2011 John Wiley & Sons, Ltd.

Performance of a Wind-Diesel Hybrid Power System with STATCOM as a Reactive Power Compensator

The paper deals with automatic reactive power control of an isolated wind-diesel hybrid power system. The power is generated by diesel engine and wind turbine as prime movers with electrical power conversion by permanent-magnet synchronous generator (PMSG) and permanent-magnet induction generator (PMIG) respectively. The mathematical model of the system developed is based on reactive power flow equations. The paper investigates the dynamic performance of the hybrid system for 1% step increase in reactive power load with 1% step increase in input wind power.

Performance of a Wind-Diesel Hybrid Power System with STATCOM as a Reactive Power Compensator

The paper deals with automatic reactive power control of an isolated wind-diesel hybrid power system. The power is generated by diesel engine and wind turbine as prime movers with electrical power conversion by permanent-magnet synchronous generator (PMSG) and permanent-magnet induction generator (PMIG) respectively. The mathematical model of the system developed is based on reactive power flow equations. The paper investigates the dynamic performance of the hybrid system for 1% step increase in reactive power load with 1% step increase in input wind power.

Effects of the Built-in Permanent Magnet Rotor on the Equivalent Circuit Parameters of a Permanent Magnet Induction Generator

The permanent magnet induction generator (PMIG) is a new type of induction generator (IG) that has a permanent magnet (PM) rotor inside a squirrel cage rotor. The squirrel cage rotor is linked to the shaft, and the built-in PM rotor is free to rotate against the shaft. One of the notable features of the PMIG is that the power density is higher compared to a conventional IG. In this paper, the effects of the built-in PM rotor on the equivalent circuit parameters are investigated to clarify the reason for the increased power density.

Performance analysis of the permanent‐magnet induction generator under unbalanced grid voltages

AbstractThis paper presents the electrical and magnetic characteristics of a permanent‐magnet induction generator (PMIG) under unbalanced grid voltages. The method of symmetrical components and two‐dimensional finite element analysis (2D‐FEA) are used to calculate these characteristics and the results are confirmed through experiments. Even if the voltage of the power grids is unbalanced, the PMIG can operate at high efficiency over a wide range of slip and the built‐in permanent‐magnet (PM) rotor is minimally affected by the negative‐sequence rotating field. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 161(4): 60–69, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20585

電圧不平衡下におけるPM誘導発電機の動作解析

This paper presents electrical and magnetic characteristics of a permanent-magnet induction generator (PMIG) under unbalanced grid voltages. The method of symmetrical components and two-dimensional finite element analysis (2D-FEA) are used to calculate these characteristics and the results are confirmed through experiments. Even if the voltage of power grids is unbalanced, the PMIG can operate at high efficiency over a wide range of slip and the built-in permanent-magnet (PM) rotor is little affected by the negative-sequence rotating field.

単相系統に接続したPM誘導発電機の性能解析

In this paper, the single-phase operation of a permanent-magnet induction generator (PMIG) is analyzed theoretically and experimentally and is compared to that of a conventional induction generator (IG) of the same size to evaluate its usefulness. Phase balancing is achieved by connecting a phase converter across their stator windings. Based on the method of symmetrical components, the steady-state performance of both the PMIG and the IG is theoretically predicted, and the results are verified through experiments. The PMIG exhibits a higher performance, in terms of output power, power factor, and efficiency, than the conventional IG.

A Technique for the Steady-State Analysis of a Grid-Connected Permanent-Magnet Induction Generator

This paper presents a technique by which the steady-state performance of a grid-connected permanent-magnet induction generator (PMIG) can be predicted more accurately. By applying the topological principle of duality, an equivalent circuit of the PMIG is derived that takes into consideration the core loss as well as the permanent-magnet (PM) excitation. The nonlinear parameters in the equivalent circuit are modeled using curve-fitting methods. Experimental results performed on a 2.2-kW prototype PMIG demonstrate the accuracy of the proposed technique.

PM誘導発電機の磁界解析

The permanent-magnet induction generator (PMIG) is a new type of induction machine that has a permanent-magnet rotor inside a squirrel-cage rotor. In this paper, a new technique for the magnetic field analysis of the PMIG is proposed. The proposed technique is based on the PMIG's equivalent circuit and the two-dimensional finite-element analysis (2D-FEA). To execute the 2D-FEA, the phasors of primary and secondary currents are calculated from the equivalent circuit, and the input data for the 2D-FEA is found by converting these phasors into the space vectors. As a result, the internal magnetic fields of the PMIG can be easily analyzed without complicated calculations.