Modeling and Control of a UPFC System Using Pole-Placement and Hinf Robust Control Techniques

This is an open access article distributed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license (CC BY-NC-ND 4.0) https://creativecommons.org/licenses/by-nc-nd/4.0/FACTS (Flexible AC Transmission Systems) technology has now been accepted as a potential solution to the stability problem and load flow. The Unified Power Flow Controller (UPFC) is considered to be the most powerful and versatile among all FACTS devices. This paper presents the modeling and control of a UPFC system using pole-placement and H robust control techniques. A simulation study using Matlab/Simulink is presented to compare the performance of these control strategies and their robustness with respect to variations is the system parameters such as the inductance of the transmission line.Peer reviewe

Certain Investigation of Real power flow control of Artificial Neural Network based Matrix converter-Unified Power Flow Controller in IEEE 14 Bus system

The power consumption is rapid increased due to ASD (Adjustable Speed Drives) and automation in industries and large consumption of electricity in domestic regions increased the concern of the power quality. The quality of the power received in the Distribution system is altered because of the losses in the transmission system. The losses in the transmission system is mitigated using the FACTS (Flexible AC Transmission System)controller among these controllers UPFC (Unified Power Flow Controller) plays a vital role in controlling the shunt and series reactive powers in the bus of the power system. The conventional topology of the UPFC consists of AC-DC converter and energy stored in the DC link and DC-AC converter injected a voltage in series to the bus which as to be controlled. Whereas a new topology based on matrix converter can replace the dual converters and perform the required task. The construction of 2-bus, 7-bus and IEEE-14-bus power system is designed and modeled. MC-UPFC (Matrix Converter Based Unified Power Flow Controller) is designed and constructed. The MC-UPFC is the rich topology in the FACTS which is capable of controlling both the transmission parameters simultaneously with the switching technique of Direct power control by the smooth sliding control which gives less ripple in the injecting control parameters such as control voltage [Vc] and voltage angle [α]. By implementing MC-UPFC the real and reactive power can be controlled simultaneously and independently. The control techniques were designed based on the Proportional Integral derivative(PID) with sliding surface power control, FLC (Fuzzy Logic Controller) and ANN (Artificial Neural Network)  and  the performance of  Vc and α of the controllers are investigated. Hence the sliding surface and relevant control switching state of the MC can be controlled by the FLC which gives the robust and autonomous decision making in the selection of the appropriate switching state for the effective real power control in the power system. The work has been carried out in the MATLAB Simulink simulator which gives the finest controlling features and simple design procedures and monitoring of the output

Analysis and robust decentralized control of power systems using FACTS devices

Today\u27s changing electric power systems create a growing need for flexible, reliable, fast responding, and accurate answers to questions of analysis, simulation, and design in the fields of electric power generation, transmission, distribution, and consumption. The Flexible Alternating Current Transmission Systems (FACTS) technology program utilizes power electronics components to replace conventional mechanical elements yielding increased flexibility in controlling the electric power system. Benefits include decreased response times and improved overall dynamic system behavior. FACTS devices allow the design of new control strategies, e.g., independent control of active and reactive power flows, which were not realizable a decade ago. However, FACTS components also create uncertainties. Besides the choice of the FACTS devices available, decisions concerning the location, rating, and operating scheme must be made. All of them require reliable numerical tools with appropriate stability, accuracy, and validity of results. This dissertation develops methods to model and control electric power systems including FACTS devices on the transmission level as well as the application of the software tools created to simulate, analyze, and improve the transient stability of electric power systems.;The Power Analysis Toolbox (PAT) developed is embedded in the MATLAB/Simulink environment. The toolbox provides numerous models for the different components of a power system and utilizes an advanced data structure that not only increases data organization and transparency but also simplifies the efforts necessary to incorporate new elements. The functions provided facilitate the computation of steady-state solutions and perform steady-state voltage stability analysis, nonlinear dynamic studies, as well as linearization around a chosen operating point.;Applying intelligent control design in the form of a fuzzy power system damping scheme applied to the Unified Power Flow Controller (UPFC) is proposed. Supplementary damping signals are generated based on local active power flow measurements guaranteeing feasibility. The effectiveness of this controller for longitudinal power systems under dynamic conditions is shown using a Two Area - Four Machine system. When large disturbances are applied, simulation results show that this design can enhance power system operation and damping characteristics. Investigations of meshed power systems such as the New England - New York power system are performed to gain further insight into adverse controller effects

Effect of Unified Power Flow Controller on Power System Performance: A Case Study of Maryland 132/33/11 kv Transmission Station

This work examines the effect of Unified Power Flow Controller (UPFC) on power system performance using Maryland 132/33/11 kV transmission station as a case study. The transmission network consists of Alausa, Police Training College and Mushin 33 kV feeders and T1A-15 MVA, T2A-15 MVA and T3A-15 MVA 33/11 kV tertiary transformers with their respective peak load designated A-F. The developed model equations for the network without and with UPFC were implemented using Matlab/Simulink software (R2009b Version). The system’s performance was further examined by introducing a fault condition on D and E transformers. With A-F as 25, 37.5, 12.5, 12.5, 12.5 and 37.5 MW respectively, the average voltage improved from 0.95297, 0.93832, 0.93952, 0.93123, 0.91937 and 0.95297 p.u. respectively without the UPFC to 0.96142, 0.95560, 0.94782, 0.93838, 0.92755 and 0.96142 p.u. respectively when the UPFC was applied. Similarly, the average power improved from 3.55883, 6.85067, 9.8335, 12.4735, 14.74483 and 6.85067 MW respectively without the UPFC to 3.62233, 6.97133, 10.0095, 12.6952, 15.0113 and 6.97133 MW respectively with the UPFC. Also, for the earth fault introduced on D and E transformers, the average voltage improved from 0.4467 and 0.84005 p.u. respectively without the UPFC to 0.4507 and 0.8475 p.u. respectively with the UPFC. The average power similarly improved from 1.9435 and 5.3665 MW respectively without the UPFC to 1.9775 and 5.4625 MW respectively when the UPFC was applied. The results of this work showed that the application of UPFC on the Maryland transmission network appreciably improved the voltage and power profiles of the system

Study of Power Flow Control Using FACTS Devices

With most of the countries on the threshold of industrialization the demand for electrical power also continues to increase steadily and is predominantly strong. Moreover, because the transmission systems are operated near to their thermal and stability limits, the chief challenge for the power industry is to supply electrical power to match the demands of the consumers with the minimum amount of losses while maintaining adequate power quality level. For various reasons, newly installed transmission lines are unable to cope up with the growing power generation. This paper presents the ideas of using FACTS devices for enhanced operation and more effective usage and control of the existing transmission network framework. The development of Flexible AC Transmission Systems, or FACTS based on high power electronics, offers a powerful means of meeting the challenges

MODELING AND CONTROL OF INTERLINE POWER FLOW CONTROLLER FOR POWER SYSTEM STABILITY ENHANCEMENT

Mitigation of power system oscillations is the problem of concern in the power industry as these oscillations, when exhibiting poor damping; affect the transmission line power transfer capability and power system stability. These oscillations greatly restrict power system operations and, in some cases, can also lead to widespread system disturbances. In this context, the Flexible AC Transmission System (FACTS) device, Interline Power Flow Controller (IPFC) employed to improve the transmission capability can be additionally utilized for damping control of power system oscillations. IPFC based damping controller design for power system stability requires proper and adequate mathematical representation of power system incorporating the FACTS device. This thesis reports the investigation on the development of steady state model, the dynamic nonlinear mathematical model of the power system installed with the IPFC for stability studies and the linearized extended Phillips Heffron model for the design of control techniques to enhance the damping of the lightly damped oscillations modes. In this context, the mathematical models of the single machine infinite bus (SMIB) power system and multi-machine power system incorporated with IPFC are established. The controllers for the IPFC are designed for enhancing the power system stability. The eigenvalue analysis and nonlinear simulation studies of the investigations conducted on the SMIB and Multi-machine power systems installed with IPFC demonstrate that the control designs are effective in damping the power system oscillations. The results presented in this thesis would provide useful information to electric power utilities engaged in scheduling and operating with the FACTS device, IPFC

Virtual Laboratory for Power Electronic Based Reactive Power Compensators

The practical application is important in engineering education. However, in some cases, such as fund deficiency, practical applications may not be possible. In addition, this case restricts closely to pursue the novel technologies. Depending on developments in power electronics and microprocessor fields, use of Flexible Alternating Current Transmission Systems (FACTS) devices have been becoming more common. Practical applications on these devices are insufficient in undergraduate education. This study presents a virtual laboratory application for power electronics based FACTS devices. The virtual laboratory for education of advanced compensation method is prepared by using MATLAB GUI. The all parameters belonging to the related circuit can be accessed via the prepared virtual laboratory. Over a visual interface, current, voltage and power values can be observed. Theoretical information about the related subject is also included in the prepared virtual laboratory. All possible applications can be done even if users do not know MATLAB Programming Language, GUI, any formula or command from Simulink. User can repeat the application as much as they want and observe results obtained from different parameter values

Power Flow Control of Power Systems Using UPFC Based on Adaptive Neuro Fuzzy

Optimization of system capacity electric power transmission systems requires a reliable power flow controller. The power flow controllers must be able to control the level of electrical voltage and active and reactive power flow without reducing the level of stability and security of the transmission system. Latest technology in the control of power flow is a Unified Power Flow Controller (UPFC). The entire transmission line parameters are impedance, voltage, and phase angle can be controlled simultaneously by the UPFC. The method used in the conventional algorithms based UPFC is still firmly with logic. These algorithms have difficulties to electric power transmission systems multimachine very dynamic, i.e. systems that are experiencing rapid changes in the electrical load from time to time. Therefore, in this study was developed based on neuro-fuzzy method is applied to the adaptive UPFC for adaptively controlling the power flow in electric power transmission systems multimachine very dynamic. In this study, three phase fault is applied to the multimachine system. The results are taken to be consideration of PI and neuro-fuzzy controllers. The PI and neuro-fuzzy controllers show nearly same results but there is a low overshoot occurred during the fault in the neuro-fuzzy controllers results. According to results that UPFC improves the system performance under the transient and the normal conditions. However, it can control the power flow in the transmission line, effectively

STATCOM Controller (Design and Assessment) for Transmission and Distribution System Problems

Due to immense increase in needs of human being, the power generation system encounters a deficiency of key energy sources as a result the demand is increasing day by day without an increase in alternative generation resources and transmission line capability. The constantly increase of electrical power        demands and loads, especially non-linear loads making the power system network become more        complicate to operate and the system becomes unstable with large power flows without proper control and operation. The advancement in power system with time have brings new challenges and sometimes it is difficult to operate system in stable condition due to complex    system network. One of the invention of power electronics is FACTS technology. FACTS (Flexible Alternating Current Transmission Systems) devices are based on power electronics and other dynamic controllers that provide control of one or more AC transmission system parameters to upgrade the controllability and to increase power transfer capability. One way to improve the power system control is by applying FACTS controllers such as D-STATCOM (Distribution Static Synchronous Compensator) which can be introduced to the power    system to regulate terminal voltage and to improve power factor of system.A comprehensive D-STATCOM controller is to be established which when will be introduced in the    power system will eliminate the voltage fluctuations and improve power stability. A test power system is    being designed in MATLAB Sim Power System with non-linear load and wind energy source as          renewable source and then the systems is analyzed with and without the D-STATCOM controller and both the result are being compared to check the performance of the designed D-STATCOM Controller. Keywords: Unified Power Flow Controller (UPFC), Distribution Static Compensator (D-STATCOM), Static Synchronous Series Compensator (SSSC

PEMODELAN DAN SIMULASIPIRANTI FLEXIBLE AC TRANSMISSIONSISTEM (FACTS DEVICES)-UNIFIED POWER FLOW CONTROLLERPADA SMIB-SISTEM TENAGA LISTRIK

Unified Power Flow Controller (UPFC) mampu berperan sebagai piranti dalam pengendalian, Voltage Control, Transient Stability, Damping Power Oscillation, Ractive Power Compensation, Power Flow Controller   dan  SSR Mitigation. Penggunaan Fungsi UPFC sebagai piranti FACTS DEVICES untuk peredam Osilasi, Unified Power Flow Controller sebagai piranti Flexible AC Transmission Sistems dengan parameter pengamatan tegangan, impedansi,  dan sudut fasa dalam kajian studi stabilitas dinamis, pengaturan aliran daya serta keandalan pada sistem tenaga listrik dalam memperbaiki osilasi stabilitas sitem tenaga dengan pemasangan UPFC (Unified Power Flow Controller). Model sistem Single Machine Infinite Bus (SMIB) dengan UPFC yang dipasang pada saluran transmisi daya listrik, dapat memperbaiki osilasi, UPFC di modelkan dengan persamaan state-space kemudian model di susun dalam blok simulasi menggunakan Simulink. Step respon input simulasi digunakan sebagai asumsi adanya perubahan yang terjadi pada sistem akibat gangguan. Hasil simulasi, penggunaan UPFC sebagai piranti FACTS dapat memperbaiki Osilasi akibat gangguan dinamik pada siste