A comparison between SVC and STATCOM in flicker mitigation of electric arc furnace using practical recorded data

Flexible AC Transmission System (FACTS) controllers are advanced power electronic devices employed in electrical power systems to enhance system stability, reliability, and power transfer capabilities. These controllers enable dynamic and flexible control of various transmission parameters such as voltage, current, impedance, and phase angle, thereby improving the overall power system performance. FACTS devices are broadly classified into series, shunt, series- series, and series-shunt configurations, each designed to manage reactive power and regulate voltage either by injecting voltage in series or current in shunt with the transmission line. Well-known FACTS devices include Static Var Compensators (SVC), Static Synchronous Compensators (STATCOM), Thyristor Controlled Series Capacitors (TCSC), Static Synchronous Series Compensators (SSSC), and Unified Power Flow Controllers (UPFC), each serving specific roles in power flow control, voltage regulation, and transient stability enhancement. The integration of these controllers provides significant benefits such as increased transmission line capacity, improved voltage stability, minimized transmission losses, and damping of power system oscillations. They are capable of rapid response during transient disturbances, effectively mitigating voltage collapses and enhancing system resilience against faults and contingencies. FACTS controllers not only improve steady-state operational parameters but also address dynamic stability and transient conditions, enabling power systems to operate closer to their stability limits while maintaining security. Their deployment helps avoid costly infrastructural expansions by optimizing existing transmission assets, which is critical given environmental and economic constraints. Recent advances in semiconductor technologies and control algorithms have made FACTS devices more reliable, efficient, and adaptable to modern grids, including renewable integration and deregulated power markets. In summary, FACTS controllers play a vital role in modern power systems by providing flexible, efficient, and reliable solutions for power flow management, voltage control, and system stability enhancement, thereby supporting the evolving demands of today's complex electrical networks.

In the transition towards renewable energy systems, the integration of large-scale renewable energy sources (RES) introduces significant operational challenges due to their intermittent nature and lack of physical inertia. This paper explores the efficacy of two Flexible AC Transmission System (FACTS) devices, the Static Synchronous Compensator (STATCOM) and the Static VAR Compensator (SVC), in mitigating the destabilizing effects associated with high levels of RES integration. Through simulation of various contingencies at a Real Time modeled 400kV Pooling Substation, the performance of STATCOM and SVC, each rated at 150 MVAr, is analyzed in maintaining grid stability. Findings highlight STATCOM’s superior dynamic response in managing voltage fluctuations and enhancing system damping compared to SVC. Specifically, STATCOM demonstrates a quicker and more robust capability to inject reactive power during disturbances, thereby ensuring rapid stabilization of grid operations. This research underscores the critical role of advanced FACTS devices in sustaining grid reliability and offers strategic insights for grid operators and policymakers aiming to optimize renewable energy integration without compromising grid stability.

Comparison of BBO, WIPSO & PSO Techniques for the Optimal Placement of FACTS Devices to Enhance System Security

7 - Modern flexible AC transmission system (FACTS) devices

In this paper, a hybrid tabu search and simulated annealing (TS/SA) approach is proposed to minimize the generator fuel cost in optimal power flow (OPF) control with multi-type of flexible AC transmission systems (FACTS) devices. The problem is decomposed into the optimal setting of FACTS parameters subproblem that is searched by the hybrid TS/SA approach and the OPF with fixed FACTS parameters subproblem that is solved by the quadratic programming (QP). Four types of FACTS devices are used: thyristor-controlled series capacitor (TCSC), thyristor-controlled phase shifter (TCPS), unified power flow controller (UPFC), and static VAr compensator (SVC). Test results on the modified IEEE 30 bus system with multi-type of FACTS devices indicate that the proposed hybrid TS/SA approach can obtain better solutions and require less CPU times than genetic algorithm, SA, or TS alone. Using multi-type of FACTS devices results in less total generator fuel cost than using individual FACTS device.

High electricity growth in Nigeria coupled with an obsolete transmission network has necessitated novel approaches to power grid optimization. This paper compares the two technologies- Solar Photovoltaic (PV) system and Flexible AC Transmission System (FACTS) devices, in particular Static Synchronous Compensator (STATCOM), individually embedded to the 330 kV Nigeria 48-bus transmission grid in a simulation-based study. With the assistance of Power System Analysis Toolbox (PSAT) in MATLAB, this paper summarizes how these are the technologies that developed to increase Available Transfer Capability(ATC), gain better voltage stability and change power flow under normal as well as under Single Line Contingency. Five weak buses were used for the simulation featuring poor voltage performance and three deployment confirmations were studied (FACTS, PV, and the the base case without any enhancement). The results prove that solar PV and FACTS devices can independently be used to enhance the performance. ATC enhancement of FACTS deployment are almost 35.7% in ATC whereas solar PV gave an ATC enhancement of 29.6%. Voltage variation was decreased by 24.6% and 29.4% in the FACTS-only and PV-only case respectively, over the base case. These findings imply that FACTS has more transfer capacity, while PV systems have more voltage support. The results of this study offer valuable knowledge for power system planners and decision makers in developing countries where additional infrastructure development may not be feasible or immediate, but a need to reinforce the transmission network using flexible and low-cost solutions exists.

The increasing demand for reliable and high-quality electrical power has led to the development of advanced techniques for controlling power flow in transmission networks. Flexible AC Transmission Systems (FACTS) are key technologies designed to enhance the controllability and stability of AC power systems. Among FACTS devices, the Static VAR Compensator (SVC) is widely used to regulate voltage, improve power factor, and maintain system stability under varying load conditions. This project focuses on the design and implementation of a Static VAR Compensator for improving voltage stability and reactive power management in an AC transmission system. The SVC achieves rapid reactive power compensation using thyristor-controlled reactors (TCRs) and thyristor-switched capacitors (TSCs), allowing dynamic adjustment to changing system conditions. By maintaining voltage within desired limits, the SVC enhances the reliability, efficiency, and operational flexibility of the transmission network. The project includes simulation and analysis of the SVC in different loading scenarios to demonstrate its effectiveness in reducing voltage fluctuations, improving power quality, and minimizing transmission losses. The implementation of SVC in a transmission system represents a cost-effective solution for modern power systems, enabling better control of power flow and contributing to the stability of the electrical grid.

This paper investigates a novel optimization-based methodology for placement of Flexible AC Transmission Systems (FACTS) devices in order to avoid congestion in the transmission lines while increasing static security margin and voltage profile of a given power system. The optimizations are carried out on the basis of location, size, and number of FACTS devices. Thyristor Controlled Series Compensator (TCSC) and Static Var Compensator (SVC) are two FACTS devices which are implemented in this investigation to achieve the determined objectives. The problem is formulated according to Sequential Quadratic Programming (SQP) problem in the first stage to accurately evaluate static security margin with congestion alleviation constraint in the presence of FACTS devices and estimated annual load profile. In the next stage a Genetic Algorithm (GA)-based fuzzy multi-objective optimization approach is used to find the best trade-off between conflicting objectives. The IEEE 14-bus test system is selected to validate the proposed approach.

This paper primarily focuses on an investigative study on allocating Flexible AC transmission system (FACTS) devices on radial distribution systems. The FACTS device that is used in this paper is static var compensator (SVC). In this paper, SVC is placed on each bus except substation bus and study the results to find the best location for allocation. A design of SVC was done by fixed reactance method. The total power loss of network and voltage of nodes have been analyzed for each allocation and the sequences of each implementation have been compared to find the best location of SVC. The proposed algorithm has been executed on IEEE 33-bus and 69-bus standard test systems.

<span>The rise in demand for electricity and the high cost of constructing new power networks reckons optimal utilization of electric power overloading and excessive power transfer along transmission lines, high losses, voltage instability, poor power quality, reliability issues. Flexible AC transmission system (FACTS) boosts the static and dynamic performance of power systems. Although efficient power transmission by improving power quality and voltage profile enhancement is controlled using the FACTS devices the placement, types, and sizing are important parameters to be optimized for the power system. This paper develops the economic multiple FACT placements and sizing solution during N-1 contingency conditions. Placement and sizing being the stochastic problem meta-heuristic algorithm genetic algorithm (GA) is used and applied on the standard IEEE 9 bus system. MATLAB-based simulation is developed for economic placement of multiple FACTS and single FACTS devices in different scenarios (without FACTS devices, with single FACTS devices, and with multiple FACTS devices). Both static VAR compensators (SVC) and thyristor-controlled series capacitors (TCSC) are used (either single or multiple) to optimize the transmission loss and total cost. The results show that transmission loss and cost reduction with 70% compensation is working better with about 0.1 MW lesser loss in many cases.</span>

Comparison of computational intelligence algorithms for loadability enhancement of restructured power system with FACTS devices

Fuzzy based evolutionary algorithm for reactive power optimization with FACTS devices

Flexible AC transmission systems (FACTS) technology is widely adopted and utilized to maintain the performance of power systems. However, the improvements of power system performance achieved by FACTS devices depend on the right sizing and allocation of such devices. For technical and economic considerations, a FACTS device's location and size should be selected very carefully in order to maximize its benefits to the power system. In this paper, the sizing and location of a static VAR compensator (SVC) are optimally determined using a new optimization technique called lightning attachment procedure optimization (LAPO). The optimal allocation of the SVC is determined regarding the improvement of voltage deviation index and the reduction of total active power losses. The system is optimized in two cases: once without SVC installation in order to find out the optimal settings of the system that achieve the objective functions, and another time with SVC installation to determine its optimum sizes and locations by which the required objective functions are achieved. Then the system performance is analyzed after optimization with and without SVC devices to show the impact of the optimum sizing and location of the SVC on the system. The study is validated using the standard IEEE 30-bus system, while the developed LAPO is performed by MATLAB M-Files and the system performance analysis in different cases is performed by NEPLAN software.

Coordinated reactive power management in power networks with wind turbines and FACTS devices

In this paper, a new and easy to implement heuristic method related to the Artificial Bee Colony (ABC) algorithm is proposed for the optimal location of shunt connected Flexible AC transmission systems (FACTS) devices such as Static Var Compensator (SVC) and Static Synchronous Compensator (STATCOM) randomly and dynamically. Voltage stability enhancement, voltage profile improvement and active power loss minimization by using minimum number of devices and var compensator sizing are defined as the objective functions for the proposed methodology. Optimization results of the bi-objective and multi-objective functions are compared with the results reported in literature. Also, by comparing the results obtained by using ABC algorithm and Differential Evolution (DE) method, it can be stated that proposed algorithm can converge to better results by using minimum device number.