STATCOM

When there is an unpredictable reduction in voltage due to a sudden increase in load demand, a change in system condition, or a large disturbance in load demand, the power system becomes unstable. The ability of the power system to maintain acceptable voltages at all buses in the system under normal conditions and after being subjected to disturbance is referred to as voltage stability. The facts device is particularly important for enhancing voltage stability. Voltage stability analysis can be performed in a variety of ways, including examining undersized networks analytically using mathematical splits as a stability requirement. Voltage stability analysis can be implemented using a variety of methods. FACTS technology is a collection of high-power controllers, rather than a single high-power controller. Fact devices come in a variety of shapes and sizes. Static Synchronous Compensator is abbreviated as STATCOM. Statcom is one of the most important Voltage Source Converter (VSC)-based Flexible Ac Transmission Systems (FACTS) devices. In this work, an optimization analysis technique is used to identify weak buses, and once the weak buses have been identified, fact devices will be installed at the needed locations to improve voltage stability. The genetic algorithm (GA) is a well-known optimization technique that is utilised in this research to determine the best site for statcom placement in the power network for IEEE 14 and IEEE 30 bus systems. In addition, the performance of the network will be compared with and without the use of a statcom in the power network.

STATCOM is one of FACTS devices that used as regulator for transmission and distribution systems which works for reactive power compensation. STATCOM utilisation in distribution system mostly for enhancing the profile of voltage, where used for adjusting the disturbance voltage by injecting into the system a controllable voltage. This paper present a Fuzzy controller based on STATCOM to enhance the voltage profile in distribution network. The controller of STATCOM has simulated for different types of abnormal load conditions of balance and unbalance load. The results of simulation show ability of proposed design to enhance the load voltage which was 96% of the nominal value. 1. INTRODUCTION STATCOM is one of the most important devices can be used in power flow control and power quality, which permit a utilise function in the prepared in the manner that without any loss the performance expectation. The equipments such as transformer, motor, computer, printer, equipment of communication and all types of house machines. These equipments mentioned were affect to the quality of power negatively [1]. When a large load in the network the reactive power unable to be transmitted even though with essential of buses voltage magnitude [2]. Voltage instability cause complete or partial discontinuation in the network. The STATCOM advantage is that can regulate efficiently the injected current in to the bus [3]. Also STATCOM has several applications in compensation of the conditions of sag/swell, the Suppressing in harmonics of line currents and improve the power factor in the load, and reactive power compensation in transmission line also in the load also STATCOM mitigate the fluctuations of the bus voltage [4, 5]. STATCOM with storage energy is advisable for controlling the injected voltage in its magnitude and also the angle by VSC "Voltage Source Converter" for controlling the powers "active and reactive" of STATCOM [6]. Many works have been suggested for the implementation of voltage profile enhancement in the literature. Improving Voltage Profile using PI Controller in [7]. Whereas [8] presents Optimal location of UPFC to enhence voltage profile. In [9] presents Enhancement of voltage profile using SVC. The use of PI controller in [7], has many drawbacks that needs tunning at each operating point, slow in response and less smoother. The use of UPFC in [8], needs settings and controllers for both STATCOM and also for SSSC. The use of SVC in [9], have passive parameters that affect to the tuning of the system and nake some oscillation in response. The new porposed of STATCOM for voltage profile enhancement with Fuzzy logic control is a high-speed response and smoother than conventional controller also the propsed system use VSC instead of passive element in SVC. The use of d-q theory to calculate the reactive power and the bus voltage

— Wind energy has become one of the subjects of much recent research and development all over the world. Interconnection of wind farms into power grids, especially weak grids, brings voltage stability problems during grid-side disturbances. This paper studies the voltage stability of a large doubly-fed induction generator (DFIG)-based wind farm, connected to a modified IEEE 14 bus network during system disturbances such as load change, three-phase fault, or voltage swell/sag. Flexible AC transmission system devices (FACTS), such as static bar compensator (SVC) and static synchronous compensator (STATCOM), are installed along with wind farms to maintain voltage and frequency within grid codes. MATLAB/SIMULINK and Power System Analysis Toolbox (PSAT) package are used for the simulation.

İndiksiyon ve iki beslemeli indiksiyon generatörleri rüzgar gücü sistemlerinde elektrik üretimi için yaygın olarak kullanılır. İndiksiyon generatörlerin ve iki beslemeli indiksiyon generatörlerin tanımları rüzgar enerji sistemleri için bu çalışmada verilmiştir. Farklı bağlantı tipleri ve koşulları iki farklı rüzgar jeneratörü için şebeke ve rüzgar türbinleri için bu çalışmada incelenmiştir. Bir rüzgar çiftliği modeli indiksiyon generatörü ve iki beslemeli indiksiyon generatörü için MATLAB/Simulink de modellenmiştir. İlk olarak simulasyon sonuçları normal çalışma koşulları için sunulmuş ve tartışılmıştır. İkinci olarak ise rüzgar çiftliği modeli hata durumları için simule edilmiştir. Farklı hata koşulları altındakı bu IG ve DFIG sonuçları statik kompanzatörün bir fonksiyonu olarak verilmiş ve tartışılmıştır. Bu sistemin üstünlük ve dezavantajları verilmiş ve değerlendirilmiştir. https://dx. Induction and doubly-fed induction generators are widely used in wind power systems for electricity generation. Description of induction generator (IG) and doubly-fed induction generator (DFIG) for wind power generation systems are given in this paper. Different connection types and conditions for two different types of wind generators with the grids and wind turbines are investigated in this study. A wind farm model is simulated using an induction generator and a doubly-fed induction generator in MATLAB/Simulink. The simulation results under normal operating conditions are presented and discussed firstly. Wind farm models are simulated under fault conditions secondly. The results of the IG and DFIG system under various fault conditions as a function of static compensator (STATCOM) are presented and discussed. The superiority and disadvantages of this system are given and evaluated. https://dx.

This paper presents the enhancement of voltage stability using Static Synchronous compensator (STATCOM) and Static Synchronous series compensator (SSSC). In recent past years, along with the rapid increasing electrical power requirement has caused system to be heavily loaded leading to voltage instability. Under this condition there may be insufficient reactive power causing voltage to drop at various buses. The result would be the occurrence of voltage collapse which leads to total blackout of the whole system. FACT controllers have been used for solving various stability control problems. In this paper, SSSC and STATCOM are used to investigate the effect of these devices in controlling active and reactive powers to maintain voltage stability. The PI Controller is used to tune the circuit and to provide the zero signal error. Simulation results have been presented in MATLAB/Simulink environment for two machines four buses system.

Grid integration of intermittent renewable energy sources like wind and solar is usually associated with power quality disturbance especially when the penetration level is high. This paper investigates the power quality issues associated with grid connected wind power plant (WPP) and how to overcome such problems using static synchronous compensator (STATCOM) – a member of Flexible A.C Transmission System (FACTS) devices. The major power quality issue investigated in the paper is harmonic distortions. Other power quality parameters such as voltage dip, voltage swell, flicker, transient, short and long interruptions were also briefly introduced. The entire system including the STATCOM control scheme is simulated in Simulink environment of MATLAB. Simulation results show that the harmonic contents at the output of the system with unfiltered linear loads are quite high, thus showing power quality deterioration. Fast Fourier Transform (FFT) analysis on the voltage and current waveforms of the system show that the STATCOM control scheme is capable of cancelling out the reactive and harmonic parts of the load current thereby restoring the smooth sinusoidal waveform of the voltage and current at the wind point of interconnection (POI), or point of common coupling (PCC) which signifies power quality improvement.

In this paper presents the Simulation of a 14-bus system using STATCOM compensated by applying the error and see the impact of the voltage compensator buses. Voltage stability of a system is affected by reactive power limit of the system. FACTs devices improve the reactive power flow in system thereby improving voltage stability.
This paper explores the effect of STATCOM on static voltage stability. IEEE-14 bus system has been used to demonstrate the ability of STATCOM in improving the voltage stability margin. These FACTs controllers help to increases the load ability margin of the power network. Modelling & simulation is performed on MATLAB SIM power system block set.

— In recent years, much attention has been attracted to the problems of voltage quality for the electrical power systems. Because of continuous increase of power demands and large scale system interaction as well as the consideration of both the economic benefit and the environment protection, modern power system are operated more and more close to the their maximum operating conditions. As a consequence, some transmission lines are heavily loaded and the system stability becomes a power transfer-limiting factor. In these days, voltage of the system can be control in many ways and the latest technology by using power electronic device that we call as FACTS-devices. Flexible Ac Transmission System (FACTS) devices are the option to mitigate voltage instability by reactive power flow and voltage control criteria. It has lot of configuration like series, shunt etc. TCSC is series type and STATCOM is shunt type controller. In this paper both the devices are compared for voltage stability enhancement.

Electricity grid upgrades, including construction of new transmission
lines, cannot keep pace with the growing power plant capacity and
energy demand. Thus it is necessary to rely on optimum utilization of
existing transmission and distribution infrastructure by improving the transient and steady state stability which can be achieved with the help of reactive power compensation. As both utilities and consumers become more aware of standards to be maintained and appropriate mitigation techniques, dynamic reactive power compensation using STATCOM will play an increasingly important role in the years to come.

The sources such as wind power and solar power are expected to be promising energy sources when it is connected to the power grid.  The wind energy generation, utilization and its grid penetration in electrical grid are increasing worldwide.  The wind power injection into an electric grid affects the power quality due to the continuous fluctuations in nature of the wind. This weak interconnection of wind generating source in the electrical network affects the power quality and reliability.
　　The increasing use of power electronic based loads such as adjustable Speed drives, Switch mode power supplies, etc to improve system efficiency and Controllability is increasing concern for harmonic distortion levels in end use facilities and on overall power system.THD reduction and Total Power factor improvement at the source end in the integration of wind power to the grid are the main issues addressed in this thesis. Here, a control scheme based on Indirect Current Control Algorithm  is used for compensating the reactive power requirement of a three phase grid connected wind driven induction generator as well as the harmonics produced by the non linear load connected to the PCC using VSI based STATCOM along with Battery energy storage system. The above proposed control scheme is simulated using MATLAB/SIMULINK.
　　In this paper the simulation study is extended to study the performance of STATCOM with BESS during the 3-phase fault state with measurement of THD reduction and PF improvement.

Keywords- STATCOM, Indirect Current Control algorithm, BESS, Hysterisis current controller.

This paper presents a study of FACTS devices mainly static VAr compensator (SVC) and controlled series compensator (CSC). Their steady-state modeling and effects on power system performance have been studied. It also studies static stability improvement of a power system and hence power flow improvement in the network. Standard stability evaluation technique has been used to identify the optimum place for the implementation of flexible AC transmission system (FACTS) devices and the effects of FACTS on system loadability has been studied and presented here. The technique to identify the optimum location for the placement of FACTS devices is based on the concept of maximum power transferring capability of the lines and buses. The study has been carried out on the IEEE 24 and 118 bus test systems. Study reveals that incorporation of FACTS devices significantly enhanced system stability as well as power transfer capability of the system.
Published in: 2000 TENCON Proceedings. Intelligent Systems and Technologies for the New Millennium (Cat. No.00CH37119)

The theme in the project is going to describe how the STATCOM is used for the correction of power factor in the transmission line. The presence of reactive power causes the real power to be less than the apparent power, and so, the electrical load has the power factor of less than unity. This study deals with low power factor issues and its improvement technique. A Static Synchronous Compensator (STATCOM) is implemented at transmission level for meeting reactive power demand of load for improving power factor to unity and for regulating voltage. The detailed modeling for this project will be simulated using MATLAB.

In this paper, a new single-phase D-STATCOM based inverter topology is presented. The proposed inverter is placed between the distributed generation source and the grid and is able to regulate active and reactive power transferred to the grid. This inverter is equipped with distribution static synchronous compensators option in order to control the power factor (PF) of the local feeder lines. Using the proposed inverter for small to medium size wind applications will eliminate the use of capacitor banks as well as FACTS devices to control the PF of the distribution lines. The goal of this paper is to introduce new ways to increase the penetration of renewable energy systems into the distribution systems. This will encourage the utilities and customers to act not only as a consumer, but also as a supplier of energy. Moreover, using the new types of converters with FACTS capabilities will significantly reduce the total cost of the renewable energy application. In this paper, modular multilevel converter is used as the desired topology to meet all the requirements of a single-phase system such as compatibility with IEEE standards, total harmonic distortion (THD), efficiency, and total cost of the system. The function of the proposed inverter is to transfer active power to the grid as well as keeping the PF of the local power lines constant at a target PF regardless of the incoming active power from the wind turbine. The simulations for an 11-level inverter have been done in MATLAB/SIMULINK.

This paper is present a novel approach for solving the pending under-reach problem encountered by distance relay protection scheme in the 3rd zones protection coverage for a midpoint STATCOM compensated transmission lines. The propose transmission line model is develop in Matlab for analyzed feature extraction using Discrete Wavelet multiresolution analysis approach. Extracted feature from standard deviation and entropy energy contents of SLG transient faults current at location beyond the integrated STATCOM used for machine learning algorithm model building using WEKA software. The Naïve Bayes classifier model perform best with robustness prediction and detection of faults with quick convergence even with less training data. The outperformance of the proposed classifier has been 100 % for the relay algorithm modification for under-reach problem elimination in 3rd zones protection coverage.

: This paper investigate about the power quality improvement in a transmission line with the help of Static synchronous
Series Compensator (SSSC). The power engineers consider rising power quality and giving certain power at the lowest cost a
major situation. For these power distribution difficulties, it is recommended to achieve some solutions in the form of a number
of power electronic based devices to the enhanced the power quality of the system. Distribution Static Compensator (SSSC),
Distribution Voltage Regulator (DVR), Unified Power Quality Compensator (UPQC), BESS, HVDC Light are few of the
prominent custom power devices employ at distribution level. The most familiar loads on such a system are the constant power,
constant impedance and constant current loads. In these cases, the voltage and current waveforms are nearly pure sinusoidal.

Over the most recent two decades, control request has expanded generously while the extension of energy age and transmission has been seriously constrained because of restricted assets and ecological confinements. As an outcome, some transmission lines are intensely stacked and the framework solidness turns into a power exchange constraining element. Adaptable AC transmission frameworks (FACTS) controllers have been for the most part utilized for comprehending different power framework unfaltering state control issues. Adaptable AC transmission frameworks or FACTS are gadgets which permit the adaptable and dynamic control of energy frameworks. Improvement of framework soundness utilizing FACTS controllers has been researched. This paper is pointed towards the advantages of using FACTS gadgets with the reason for enhancing the operation of an electrical power framework. Execution examination of various FACTS controllers has been talked about. Also, a portion of the utility experience and semiconductor innovation improvement have been inspected and condensed. Utilizations of FACTS to control framework examines have additionally been talked about.

This thesis deals with voltage drop characterization of transmission systems by using power electronics circuits supplied from embedded generation. Many grids connected power electronic systems, such as STATCOMs, UPFCs, and distributed generation system interfaces, used voltage source inverters (VSI) connected to the supply network through a filter. This filter, typically a series inductance acts to reduce the switch harmonics entering the distribution network an alternative filter is an LCL network, which can achieve reduced levels of harmonic distortion at lower switching frequencies and with less inductance, and therefore has potential benefits for higher power application. However, systems incorporating LCL filters require more complex control strategies. This dissertation proposes a robust strategy for regulating the grid current connected via an LCL filter. The strategy integrates an outer loop grid current regulator with inner capacitor current regulation to stabilize the system. Asynchronous farm PI current regulation strategy is used for the outer grid current control loop. Linear analysis, simulation and experimental results are used to verify the stability of the control algorithm across a range of operating conditions and finally expressions for "harmonic impedance" of the system are derived to study the effects of supply voltage distortion on the harmonic performance of the system.

In this paper, we presents an efficient and reliable evolutionary-based approach to solve mixed AC/DC/AC Optimal Power Flow (OPF) in electrical network by the application of the Genetic algorithm (GA's) methods, in the presence of FACTS devices in the modern electrical power networks. Our main goal is to minimize the objective function necessary for a best balance, between the energy production and its consumption in the mixed AC/DC/AC electrical networks, under normal operation. The function characterizing this balance is presented in the form of a nonlinear function, taking into account the necessary constraints of equality and of inequality. The objective function is a minimization of the cost function of the power generation and active power losses while preserving the powers of the generators, the voltages magnitudes, the capacitors of the shunts condensers, the inductances of the series reactors and the ratios of the transformers within acceptable limits. The incorporation of FACTS devices (STATCOM), the introduction of the HVDC system or a DC link and the GA method will be the main object of this study for the OPF of the mixed AC/DC/AC modern network. GA's method have been examined and tested on the standard IEEE 14-bus test system with different objectives that reflect active power losses minimization and active power generation cost minimization. The results of used method have been compared and validated with those reported in the recent literature. The results are promising and show the effectiveness and robustness of proposed approach methods.

The electrical power system is a dynamic
system which is no longer operated as isolated system, but
as interconnected system which includes thousands of
electrical elements spread over a wide area. [P.Kundru,
1994]
Power system stability is one of the most crucial issues
which deals with the response of the system to the errors
such as sudden load change, short circuit, prime mover
failure, excitation failure etc. In all these conditions to
maintain the stability or to improve the transient stability
and the damping oscillation of power system, in the n/w.
Recently, Flexible Alternative Current Transmission
System(FACTS) controllers have been proposed to
enhance the transient or dynamic stability of the power
systems.
In this paper a fuzzy logic controller is proposed to apply
a suitable control signal to STATCOM to improve the
fault clearing time and transient stability improvement
within a particular duration. The controller designed
using fuzzy logic implements human reasoning that can
be programmed into fuzzy logic language (membership
functions, rules and the rule interpretation). Here fuzzy
logic is a methodology, algorithm for optimized
implementation of controlled signal to the real system.
Proposed method is implemented in a single machine
infinite bus system and the results are compared with
conventional energy function based controllers.