Hybrid series compensation using static synchronous series compensator (SSSC) and passive series capacitor can improve the stability of the system, increases the power transfer capability and is useful for the fast control of power flow. This paper analyzes the subsynchronous resonance (SSR) characteristics of the hybrid series compensated power system in detail and proposes a simple method for the extraction of subsynchronous components of line current using filter. The extracted subsynchronous frequency component of line current is used to inject a proportional subsynchronous voltage in series with the transmission line which suppresses subsynchronous current in the transmission network. This novel technique is termed as subsynchronous current suppressor. The design of subsynchronous current suppressor is based on damping torque analysis and using genetic algorithm. A novel graphical representation of series resonance condition when SSSC is incorporated in the system is presented. The detailed study of SSR is carried out based on eigenvalue analysis, transient simulation and damping torque analysis. The results of the case study on a system adapted from IEEE First Benchmark Model demonstrates the effectiveness and robust performance of subsynchronous current suppressor in damping of SSR under various system operating conditions. © 2012 IEEE.

Thirumalaivasan R

Department of Electrical Engineering

School of Electrical Engineering

Vellore Campus

Janaki M

Prabhu N.

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Damping of SSR Using Subsynchronous Current Suppressor With SSSC

IEEE Transactions on Power Systems

This paper presents, the SSR characteristic analysis of the system with combined active and passive series compensation methods to increase secure loading, stability and fast control of power in the transmission line. The hybrid compensation is done by considering SSSC (an active FACTS device) and fixed series capacitor (passive compensation) method. Also, the Flower Pollination Algorithm is adopted in designing of the SSSC with Type-1 controller based on the damping torque analysis. The SSR analysis is carried out using damping torque, eigenvalue and transient simulation methods which show the effectiveness of SSSC in the elimination of torsional interaction at the operating point. The SSSC with Type-1 controller shows better performance in reducing the network resonant frequency along with improved power transfer capability of line. © 2019 IEEE.

2019 Innovations in Power and Advanced Computing Technologies (i-PACT)

Analysis of SSR with SSSC using FPA based Voltage Controller

In this paper, we propose a Z-source converter (ZSC)-based unified power flow controller (ZSC-UPFC) to enhance power control for long transmission lines. As a multifunctional controller, the UPFC has been adopted to regulate both the active and reactive power flows in transmission lines and to control the AC bus voltage. A recently proposed converter topology, ZSC, uses a Z-network on its DC side to support the desired AC output voltage. The proposed ZSC-UPFC configuration places a Z-network between the dc-link capacitor and the series converter to boost the series converter DC voltage. The integration of Z-network provides the desired converter voltage even with reduced dc-link capacitor voltage setting. We develop a detailed three-phase model for the proposed ZSC-UPFC by modeling the converter operation with switching functions, which are generated by the space vector pulse width modulation (SVPWM) technique. We conduct linear analysis on the D-Q model as well as extensive transient simulation (based on a detailed nonlinear three-phase model) to evaluate the performance of the overall system with the proposed ZSC-UPFC configuration. Our simulation results demonstrate the effectiveness of ZSC-UPFC: 1) The series converter provides the series compensation in a long transmission line with Z-network, and 2) the shunt converter maintains a constant dc-link capacitor voltage and provides reactive power support for the AC bus. © 1986-2012 IEEE.

IEEE Transactions on Power Electronics

Power Control With Z-Source Converter Based Unified Power Flow Controller

In a long transmission line the use of static series synchronous compensation (SSSC) with fixed series capacitor enables fast control of power flow. There is a potential risk of subsynchronous resonance (SSR) due to the series capacitor. In this paper, we propose to use the Kalman filter (KF) for state estimation of subsynchronous components present in series compensated line and the mitigation of SSR. This novel KF based SSR damping controller is referred to as KF-damping controller. The design of KF-damping controller is based on the magnitude of damping torque in the range of torsional mode frequencies. We apply the genetic algorithm to optimize the controller parameters. The proposed KF-damping controller is highly frequency selective and effectively suppresses subsynchronous components of line current in the presence of close frequency oscillations. Analytical and simulation results at various system operating conditions demonstrate the effectiveness and robustness of the proposed KF-damping controller in mitigating SSR. © 1969-2012 IEEE.

Kalman Filter based Detection and Mitigation of Subsynchronous Resonance with SSSC

The Voltage Source Converter based HVDC provides asynchronous interconnection between two AC systems. The use of VSC HVDC enables independent control of real and reactive power. Unlike conventional HVDC, the VSC HVDC does not cause Subsynchronous Resonance (SSR) when it is close to turbo-generators. The system strength of long ac transmission line can be enhanced by providing series compensation. However, there is a possibility of SSR interaction with turbine-generator due to the presence of the series capacitor in transmission line and may lead to shaft failure of the turbine-generator. The objective of this paper is to analyze the damping of subsynchronous resonance when the series compensated long AC line and VSC HVDC are originated from the same substation. A simple method for the extraction of subsynchronous component of line current using filter is proposed. The extracted subsynchronous frequency current is injected by the VSC HVDC converter close to the turbine-generator. This suppresses the subsynchronous current flowing through the generator and increases the damping of the system at critical torsional frequencies. This technique is termed as Subsynchronous Current Injection (SSCI). Subsynchronous current injector is designed using D-Q model of VSC HVDC. Genetic Algorithm (GA) is used for tuning the converter controllers and filter parameters. The results show the effectiveness of the proposed subsynchronous current injector in damping of SSR. © 2013 Elsevier Ltd. All rights reserved.

International Journal of Electrical Power & Energy Systems

Mitigation of SSR by Subsynchronous Current Injection with VSC HVDC

The Generalized Unified Power Flow Controller (GUPFC) is one of the most versatile flexible ac transmission system (FACTS) controllers which controls the active and reactive power flows in multiple transmission lines originating from a substation while controlling the sending end bus voltage. The sending end bus voltage is regulated by control of shunt reactive current while the active and reactive power flows in the transmission line are regulated by series injected voltages. This paper reports the analysis and study of Subsynchronous Resonance (SSR) characteristics of hybrid compensated system with GUPFC. The various operating mode combinations of series and shunt converters are considered to investigate their effect on SSR characteristics. The methods of analysis of SSR with GUPFC is based on the evaluation of damping torque, eigenvalues of the system and transient simulation. The computation of damping torque considers D-Q model of GUPFC to determine the torsional mode stability. The study is performed on a system adapted from IEEE Second Benchmark Model (SBM). The results demonstrate the effectiveness of series real injected voltage in mitigating the SSR. © 2013 Elsevier Ltd. All rights reserved.

Journal	Data powered by TypesetIEEE Transactions on Power Systems
Publisher	Data powered by TypesetInstitute of Electrical and Electronics Engineers (IEEE)
ISSN	0885-8950
Open Access	No