State modelling of self-excited induction generator for wind power applications (original) (raw)
Related papers
Transient Analysis of Wind Driven Self-Excited Induction Generator under Different Fault Conditions
This paper deals with the transient performance of a self excited induction generator in a wind power plant under different fault conditions. An induction generator and grid equipment may be damaged when a sudden disturbance occurs, for example, a sudden disconnection from the utility grid. The reasons for this are overvoltage and over speed. This paper also made an analysis when there is sudden disconnection of self excitation capacitance .This paper analyzes this phenomena using MATLAB/SIMULINK and coincides with its corresponding mathematical equation. Response of the system to disturbances reveals its excellent transient performance. The system has a good overload capability and is free from operational problems related with short circuit and loss of excitation.
IET Renewable Power Generation, 2021
The paper presents the performance analysis-based reliability estimation of a self-excited induction generator (SEIG) using the Monte-Carlo simulation (MCS) method with data obtained from a self-excited induction motor operating as a generator. The global acceptance of a SEIG depends on its capability to improve the system's poor voltage regulation and frequency regulation. In the grid-connected induction generator, the magnetizing current is drawn from the grid, making the grid weak. In contrast, in the SEIG standalone operation, an external capacitor arrangement is implemented to render the reactive power support. This capacitor arrangement is connected across the stator terminals during the stand-alone configuration of SEIG. The capacitor serves two purposes, which include voltage build-up and power factor improvement. Therefore, the paper deals with obtaining the minimum capacitor value required for SEIG excitation in isolated mode applications, including stand-alone wind power generation. The SEIG performance characteristics have been evaluated for different SEIG parameters. The simulation and experimental results are then compared and found satisfactory. Then, SEIG reliability is estimated considering the MCS method utilizing SEIG excitation's failure and success rates during experimental work in the laboratory. Finally, the SEIG reliability evaluation is performed considering different wind speeds. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
EXPERIMENTAL INVESTIGATION OF SELF-EXCITED INDUCTION GENERATOR FOR INSULATED WIND TURBINE
– The use of induction machine in autonomous operating mode of wind turbine generators is very appreciated in many applications for economic, logistic and technical issues. However, the induction machine model, which is naturally nonlinear, becomes more complicated with the addition of external capacitive bank for the self-excitation of the machine. The present paper provides a theoretical and experimental investigation of a self-excited induction generator (SEIG) behavior for various connection topologies by considering the machine magnetic saturation. A good agreement between simulation and experimental result is obtained from the benchmark test which includes various balanced and unbalanced loads with and without power convert.
Modelling and simulation of self-excited induction generator driven by a wind turbine
Eastern-European Journal of Enterprise Technologies, 2020
The excellent specifications of the isolated squirrel cage self-excited induction generator (SEIG) make it the first choice for use with renewable energy sources. However, poor voltage and frequency regulation (under load and speed perturbations) are the main problems with isolated SEIGs. Wide dependence on the SEIG requires prior knowledge of its behaviour with regard to variations in the input of mechanical power and output of electrical power to develop a control system that is capable of maintaining the voltage and frequency at rated values, as far as possible, with any change in the input or output power of the SEIG. In this paper, a mathematical model of a wind energy conversion system (WECS) based on a squirrel cage SEIG with a generalized impedance control (GIC) was built using the Matlab/ Simulink environment in a d-q stationary reference frame. A fuzzy logic controller (FLC) was used to control the parameters of the GIC. The training of the FLC was conducted by a neural network through Matlab's Neuro-Fuzzy designer. The results of this paper showed that the trained FLC succeeded in controlling the real and reactive power flow between the SEIG and the GIC system, in which the maximum variation for both magnitude and frequency of the generated voltage with any load or wind speed perturbation will not exceed (0.2 %) for the frequency and (3 %) for the voltage magnitude in both directions. The SEIG model was validated by comparing the results obtained with those of wellknown studies with the same rating and operating conditions
IEEE Transactions on Industry Applications, 2005
In this paper, a dynamic mathematical model to describe the transient behavior of a system of self-excited induction generators (SEIGs) operating in parallel and supplying a common load is proposed. Wind turbines with SEIGs are increasingly being used to generate clean renewable energy in rural areas owing to many economical advantages. Parallel operation of SEIGs is required where the size of the machine is a constraint. SEIGs connected in parallel experience various transient conditions such as generator/load/capacitor switching that are not easy to simulate using conventional models. An automatic numerical solution to predict the steady-state and transient behavior of any number of SEIGs connected in parallel is proposed in this paper. The generators can be of different ratings and can have different prime mover speeds. The performance of the proposed model when subjected to various dynamic scenarios is compared with experimental results. The simulation results are in good agreement with the experimental results, confirming the validity of the proposed model. An aggregated model of a small wind power system is also proposed. This model was applied to a two-wind turbine case, which can be extended to simulate a complete wind generating system.
An accurate dynamical model of induction generator utilized in wind energy systems
Indonesian Journal of Electrical Engineering and Computer Science, 2022
Due to the advantages of a self-excited induction generator (SEIG), it plays a main role in sources of renewable energy, such as wind turbines (WT). The regulation of terminal voltage and frequency is poor under variable rotor speed and load conditions at stand-alone operation mode. The generator terminal voltage depends on the excitation capacitance which can be controlled by a capacitor bank and static voltage compensator. The dynamical model of the machine is described by differential equations in D-Q axes transformations of the synchronously rotating frame. Many models of analysis are proposed in the literature. In those models, several approximations are used to simplify the process of calculations, such as neglecting the iron core resistance, stray load resistance, stator and rotor leakage reactance, and magnetic saturation. In this work, a comprehensive dynamic model of the SEIG-WT is performed to analyze the system performance under transient and steady-state conditions. This dynamic model considers the effect of all machine parameters variation. New analytical formulas are used for to accurate calculation of minimum and maximum values of excitation capacitance and generator rotor cutoff and maximum speed. The dynamic model results are partially compared with experimental results, and accurate agreement is shown.
Transient analysis of a wind-driven induction generator
Canadian Conference on Electrical and Computer Engineering 2001. Conference Proceedings (Cat. No.01TH8555), 2001
The transient behavior of wind-driven induction generator is analyzed. The generator is assumed to be running at steady-state with a certain real and reactive power flow conditions when a sudden disturbance occurs. An example of the disturbance may be a sudden disconnection from the utility grid. The generator is modeled using the universal machine model and the grid is represented by a constant voltage source. It is found that dangerous over-voltages occur few seconds after disconnection from the grid due to self-excitations at the new higher speed.
TECHNOLOGIES AND MATERIALS FOR RENEWABLE ENERGY, ENVIRONMENT AND SUSTAINABILITY: TMREES20, 2020
The three-phase self-excited induction generator (SEIG) plays a basic rule in sources of renewable energy, such as wind turbines (WT). His main defect is poor regulation of output voltage and frequency under variable rotor speed and load conditions at stand-alone and isolated area operation mode. In this paper, a complete dynamic model of the SEIG-WT system is performed to analyze and study the system performance under transient and steady-state conditions. This dynamic model considers into account the effect of saturation in magnetizing inductance, cross-coupling magnetizing inductance, stator, and rotor leakage inductances, iron core resistance, and mechanical (friction and windage ) loss resistance, as well as the effect of stray load resistance, are considered in this model.New analytical formulas are used to accurate calculation of minimum and maximum values of excitation capacitance and generator rotor cut-off and maximum speed. The results of the dynamic model are partially compared with experimental results, and accurate agree are shown.
35 Steady State Analysis of Wind Driven Self Excited Induction Generator
This paper basically deals with the steady state analysis of Self excited induction generators. MATLAB user friendly toolbox has been used to predict the performance of SEIG under different loading conditions. In this paper the algorithm to find the minimum capacitance required to calculate the excitation capacitance has been stated using the steady state analysis. In this model the excitation capacitance and the speed of the SEIG is kept constant and the experimental results and simulated results are verified.
Dynamics of wind-turbine driven Self-Excited Induction Generator with online parameter calculation
IECON 2013 - 39th Annual Conference of the IEEE Industrial Electronics Society, 2013
This paper presents the dynamics of wind-turbine driven Self Excited Induction Generator (SEIG) with the consideration of dynamic core losses and dynamic mutual inductance. The core losses when considered are often taken as function of air-gap voltage and very few researchers included the variation as function of stator synchronous frequency. Similarly in most of the cases mutual inductance is taken as constant which is a simplified version of true dynamics. In this paper simulation studies are carried out to assess the dynamic performance of SEIG considering both the core losses and mutual inductance as dynamic variables. The performance is assessed in presence of variations in rotor speed, simulated as wind's effect, by a simplified wind turbine model. It is observed that dynamic mutual inductance and dynamic rotor losses are important parameters for accurate voltage and current measurements.