Modeling and Analysis of the Dynamic Response of an Off-Grid Synchronous Generator Driven Micro Hydro Power System

2021 ◽  
Vol 10 (2) ◽  
pp. 373-384
Author(s):  
Waqas Ali ◽  
Haroon Farooq ◽  
Akhtar Rasool ◽  
Intisar Ali Sajjad ◽  
Cui Zhenhua ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Power System ◽  
Power Factor ◽  
Synchronous Generator ◽  
Operating Conditions ◽  
System Stability ◽  
Hydro Power ◽  
Modeling And Analysis ◽  
Full Load ◽  
Generator Voltage

This paper models and analyses the dynamic response of a synchronous generator driven off-grid micro hydro power system using Simulink tool of MATLAB software. The results are assessed from various perspectives including regulation through no load to full load and overload scenarios under normal and abnormal operating conditions. The investigation under the normal conditions of no load, linearly changing load and full load divulges that the system operates in a satisfactory manner as generator voltage and frequency remain approximately constant at 1 pu. However, at full load generator voltage and frequency drop 3% and 0.5% respectively from its nominal values but remain within prescribed standard IEC limits. The results also expose that the abnormal conditions produced by abrupt changes in load, system faults and severe overload, cause the unwonted variations in the magnitude of generator parameters. Moreover, the study reveals that the system stability significantly enhances when the system is run at full load because the regulation time to fix the variations in the generator parameters; except input mechanical power; decreases, e.g. from 4.1 sec to 0.8 sec for generator voltage, with the increase in the loading from quarter to full load respectively at unity power factor. Further, it is also observed that the regulation time rises, e.g. from 0.8 sec to 1.3 sec for generator voltage, with the reduction in load power factor from unity to 0.8, respectively. Thus, proper protection, to cater for increased fault current at full load and power factor correction must be provided to improve the system stability and protection. Furthermore, it is also concluded that the over loading in any case should be strongly avoided in this type of system and it should never be allowed to exceed 20% of the full load value to avoid system failure 

Modeling and Analysis of the Dynamic Response of an Off-Grid Synchronous Generator Driven Micro Hydro Power System

2021 ◽  
Vol 10 (2) ◽  
pp. 373-384
Author(s):  
Waqas Ali ◽  
Haroon Farooq ◽  
Akhtar Rasool ◽  
Intisar Ali Sajjad ◽  
Cui Zhenhua ◽  
...  
Keyword(s):  
Dynamic Response ◽  
Power System ◽  
Power Factor ◽  
Synchronous Generator ◽  
Operating Conditions ◽  
System Stability ◽  
Hydro Power ◽  
Modeling And Analysis ◽  
Full Load ◽  
Generator Voltage

This paper models and analyses the dynamic response of a synchronous generator driven off-grid micro hydro power system using Simulink tool of MATLAB software. The results are assessed from various perspectives including regulation through no load to full load and overload scenarios under normal and abnormal operating conditions. The investigation under the normal conditions of no load, linearly changing load and full load divulges that the system operates in a satisfactory manner as generator voltage and frequency remain approximately constant at 1 pu. However, at full load generator voltage and frequency drop 3% and 0.5% respectively from its nominal values but remain within prescribed standard IEC limits. The results also expose that the abnormal conditions produced by abrupt changes in load, system faults and severe overload, cause the unwonted variations in the magnitude of generator parameters. Moreover, the study reveals that the system stability significantly enhances when the system is run at full load because the regulation time to fix the variations in the generator parameters; except input mechanical power; decreases, e.g. from 4.1 sec to 0.8 sec for generator voltage, with the increase in the loading from quarter to full load respectively at unity power factor. Further, it is also observed that the regulation time rises, e.g. from 0.8 sec to 1.3 sec for generator voltage, with the reduction in load power factor from unity to 0.8, respectively. Thus, proper protection, to cater for increased fault current at full load and power factor correction must be provided to improve the system stability and protection. Furthermore, it is also concluded that the over loading in any case should be strongly avoided in this type of system and it should never be allowed to exceed 20% of the full load value to avoid system failure 

scholarly journals Synchronous Generator Model Parameter Estimation Based on Noisy Dynamic Waveforms

2016 ◽  
Vol 67 (1) ◽  
pp. 21-28
Author(s):  
Sebastian Berhausen ◽  
Stefan Paszek
Keyword(s):  
Parameter Estimation ◽  
Power Systems ◽  
Power System ◽  
Objective Function ◽  
Estimation Method ◽  
Synchronous Generator ◽  
Voltage Regulation ◽  
Operating Conditions ◽  
Synchronous Generators ◽  
Generator Voltage

Abstract In recent years, there have occurred system failures in many power systems all over the world. They have resulted in a lack of power supply to a large number of recipients. To minimize the risk of occurrence of power failures, it is necessary to perform multivariate investigations, including simulations, of power system operating conditions. To conduct reliable simulations, the current base of parameters of the models of generating units, containing the models of synchronous generators, is necessary. In the paper, there is presented a method for parameter estimation of a synchronous generator nonlinear model based on the analysis of selected transient waveforms caused by introducing a disturbance (in the form of a pseudorandom signal) in the generator voltage regulation channel. The parameter estimation was performed by minimizing the objective function defined as a mean square error for deviations between the measurement waveforms and the waveforms calculated based on the generator mathematical model. A hybrid algorithm was used for the minimization of the objective function. In the paper, there is described a filter system used for filtering the noisy measurement waveforms. The calculation results of the model of a 44 kW synchronous generator installed on a laboratory stand of the Institute of Electrical Engineering and Computer Science of the Silesian University of Technology are also given. The presented estimation method can be successfully applied to parameter estimation of different models of high-power synchronous generators operating in a power system.

Virtual Synchronous Generator Control of Power System including Large-scale Wind Farm by Cooperative Operation between Battery and LFC Hydro Power Plant

2020 ◽  
Vol 140 (6) ◽  
pp. 531-538
Author(s):  
Kotaro Nagaushi ◽  
Atsushi Umemura ◽  
Rion Takahashi ◽  
Junji Tamura ◽  
Atsushi Sakahara ◽  
...  
Keyword(s):  
Power Plant ◽  
Power System ◽  
Large Scale ◽  
Wind Farm ◽  
Synchronous Generator ◽  
Hydro Power ◽  
Virtual Synchronous Generator

PID Parameters Tuning Based on Wavelet Neural Network for Automatic Voltage Regulator Control System

2012 ◽  
Vol 463-464 ◽  
pp. 1663-1667
Author(s):  
Hai Na Hu ◽  
Wu Wang
Keyword(s):  
Neural Network ◽  
Control System ◽  
Power System ◽  
Synchronous Generator ◽  
Wavelet Neural Network ◽  
System Stability ◽  
Voltage Regulator ◽  
System Control ◽  
Automatic Voltage Regulator ◽  
Avr System

Automatic Voltage Regulator (AVR) was applied to hold terminal voltage magnitude of a synchronous generator at a specified level and its stability seriously affects the security of power system. PID control was applied for AVR system control, but the parameters of PID controller were hard to determine, to overcome this problem, some intelligent techniques should be taken. Wavelet Neural Network (WNN) was constrictive and fluctuant of wavelet transform and has self-study, self adjustment and nonlinear mapping functions of neural networks, so the structure of WNN and PID tuning with WNN was proposed, the tuning algorithm was applied into AVR control system, the simulation was taken with normal BP neural network and WNN, the efficiency and advantages of this control strategy was successfully demonstrated which can applied into AVR system for power system stability.

scholarly journals Renewable Energy System on Frequency Stability Control Strategy Using Virtual Synchronous Generator

Symmetry ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1697 ◽  
Author(s):  
Lingling Li ◽  
Hengyi Li ◽  
Ming-Lang Tseng ◽  
Huan Feng ◽  
Anthony S. F. Chiu
Keyword(s):  
Renewable Energy ◽  
Power System ◽  
Large Scale ◽  
Synchronous Generator ◽  
Frequency Stability ◽  
Stability Control ◽  
System Stability ◽  
Generator System ◽  
System Frequency ◽  
Virtual Synchronous Generator

This study constructs a novel virtual synchronous generator system based on a transfer function, and optimizes the parameters of the model by using the improved whale algorithm to improve the frequency control ability of virtual synchronous generator. Virtual synchronous generator technology helps to solve the problem that the integration of large-scale renewable energy generation into the power system leads to the deterioration of system frequency stability. It can maintain the symmetry of grid-connected scale and system stability. The virtual synchronous generator technology makes the inverter to have the inertia and damping characteristics of a synchronous generator. The inverter has the inertia characteristics and damps to reduce the frequency instability of high penetration renewable energy power system. The improved whale algorithm is efficient to find the best combination of control parameters and the effectiveness of the algorithm is verified by microgrid and power system. The results show that the proposed frequency coordination control scheme suppresses the frequency deviation of power system and keep the system frequency in a reasonable range.

scholarly journals Sliding Mode Observer-Based Load Angle Estimation for Salient-Pole Wound Rotor Synchronous Generators

Energies ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1609 ◽  
Author(s):  
Nikola Lopac ◽  
Neven Bulic ◽  
Niksa Vrkic
Keyword(s):  
Power System ◽  
Sliding Mode ◽  
Synchronous Generator ◽  
Absolute Error ◽  
Sliding Mode Observer ◽  
Adaptive Observer ◽  
System Stability ◽  
Angle Estimation ◽  
Salient Pole ◽  
Load Angle

Synchronous generator load angle is a fundamental quantity for power system stability assessment, with possible real-time applications in protection and excitation control systems. Commonly used methods of load angle determination require additional measuring equipment, while existing research on load angle estimation for wound rotor synchronous generator has been limited to the estimator based on the generator’s phasor diagram and estimators based on artificial neural networks. In this paper, a load angle estimator for salient-pole wound rotor synchronous generator, based on a simple sliding mode observer (SMO) which utilizes field current, stator voltages, and stator currents measurements, is proposed. The conventional SMO structure is improved with use of hyperbolic tangent sigmoid functions, implementation of the second order low-pass filters accompanied with corresponding phase delay compensation, and introduction of an adaptive observer gain proportional to the measured field current value. Several case studies conducted on a generator connected to a power system suggest that the proposed estimator provides an adequate accuracy during active and reactive power disturbances during stable generator operation, outperforming the classical phasor diagram-based estimator by reducing mean squared error by up to 14.10%, mean absolute error by up to 41.55%, and maximum absolute error by up to 8.81%.

Numerical Analysis of the Dynamic Flame Response and Thermo-Acoustic Stability of a Full-Annular Lean Partially-Premixed Combustor

2016 ◽  
Author(s):  
Alessandro Innocenti ◽  
Antonio Andreini ◽  
Bruno Facchini ◽  
Matteo Cerutti
Keyword(s):  
Dynamic Response ◽  
Gas Turbine ◽  
Operating Conditions ◽  
System Stability ◽  
Driving Mechanism ◽  
Heavy Duty ◽  
Flame Response ◽  
Partially Premixed ◽  
Heavy Duty Gas Turbine ◽  
Acoustic Stability

A thermo-acoustic stability of a full-annular lean partially-premixed heavy-duty gas turbine combustor is carried out in the present paper. A sensitivity analysis is performed, varying the flame temperature for two operating conditions. The complex interaction between the system acoustics and the turbulent flame is studied in Ansys Fluent, using Unsteady-RANS simulations with Flamelet-Generated Manifolds combustion model. Perturbations are introduced in the system imposing a broadband excitation as inlet boundary condition. The flame response is then computed exploiting system identification techniques. The identified flame transfer functions are compared each other and the results analysed in order to give more physical insight on the coupling mechanisms responsible for the flame dynamic response. The effect of fuel mass flow fluctuations is then introduced as further driving input, describing the flame as a Multi-Input Single-Output system. Further in-depth studies are carried out on pilot flames aiming at replicating the dynamic response of the real flame and understanding the driving mechanism of thermo-acoustic instability onset as well. The obtained results are implemented into a finite element model of the combustor, realized in COMSOL Multiphysics, to analyse the system stability. Numerical model affordability has been assessed through comparisons with results from full-annular combustor experimental campaign carried out by GE Oil & Gas since the early phases of the design and development of a heavy-duty gas turbine. This allowed the discussion of the model ability to describe the stability properties of the combustor and to catch the instabilities onset as detected experimentally. Valuable indications for future design optimization were also identified thanks to the obtained results.

scholarly journals A Feasibility Solution of a Synchronous Generator for Optimisation of the System Power Stability using an Integrated Development Environment of Visual Basic-Excel

2020 ◽  
Vol 9 (3) ◽  
pp. 1261-1268
Keyword(s):  
Power Systems ◽  
Power System ◽  
Digital Simulation ◽  
Synchronous Generator ◽  
Power System Stability ◽  
System Stability ◽  
Development Environment ◽  
Runge Kutta ◽  
Mathematical Techniques ◽  
Computational Resources

Power systems are considered highly non-linear because the environment in which they operate keep changing and hence require iterative mathematical techniques to analyse them. Such changes have a resultant effect on the system`s stability. Fluctuations in parameters are experienced in loads across the networks of the system, generator`s outputs, network topology and other operating parameters. Practically, there is no analytical solution exists for solving the problem of stability. On the other hand, there are techniques available to obtain an acceptable approximate solution of such a problem, known as digital simulation. Runge-kutta method is one of these techniques which has been used broadly as it calculates every step in a sequence of sub-steps. The method relies on a complex mathematical modelling of the synchronous generator with the help of Park-Gorev`s transformation, for the sake of simplicity and intuitiveness the method is used to analyse and study the complex equations of the three-phase synchronous generator. Generally, the system is said to be stable if the opposing forces within it are balanced and at a perfect equilibrium. The aims of this research are to establish the effects of synchronous generator`s design and transient conditions upon power system stability with the help of Embedded Microsoft Excel Sheet based on Power System Stability Analysis (EMES-PSS), using the Runge-Kutta integration method. The study has proved that EMES-PSS can find the limits of Salient and Non-Salient machines stability when changing their essential parameters. The optimisation solutions of the power system stability problem can be achieved by using basic computational resources. The software can also be used on a number of modern tablets e.g., Apple`s tablets.

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