Stabilizing Control of Series Capacitor Power System Using a Superconducting Magnetic Energy Storage Unit under unequal ?-mode (original) (raw)
Related papers
Energy Conversion, IEEE Transactions on, 1991
A systematic approach is presented to design a controller for superconducting magnetic energy storage (SMES) unit to improve the dynamic stability of a power system. The developed scheme employs a proportional-integral @'I) controller to enhance the damping of the electromechanical mode oscillation of synchronous generators. The parameters of the proposed PI controller are determined by pole assignment method based on modal control theory. Eigenvalues analysis and nonlinear computer simulations show that SMES with the PI controller can greatly improve the damping of system under various operating conditions.
Power oscillation damping by superconducting magnetic energy (SMES) storage unit
Electrical Engineering in Japan, 1994
With the increase in the size and capacity of electric power systems and the growth of widespread interconnections, the problem of power oscillations due to the reduced system damping has become increasingly serious. Since a Superconducting Magnetic Energy Storage (SMES) unit with a self-commutated converter is capable of controlling both the active (P) and reactive (Q) power simultaneously and quickly, increasing attention has been focused recently on power system stabilization by SMES control. This paper describes the effects of SMES control on the damping of power oscillations. By examining the case of a single generator connected to an infinite bus through both theoretical analyses and experimental tests (performed with a SMES unit with maximum stored energy of 16 kl and an artificial model system), the difference in the effects between P and Q control of SMES is clarified as follows: (I) In the case of P control, as the SMES unit is placed closer to the terminal of the generator, the power oscillations will decay more rapidly. (2) In the case of Q control, it is most effective to install the SMES unit near the midpoint of the system. (3) By comparing the P control with Q control, the former is more effective than the latter based on the conditions that the SMES unit location and the control gain are the same.
2014
Superconducting Magnetic Energy Storage System (SMES) includes a high inductance coil acting as a constant source of current. When a SMES is connected to a power system, it has the ability to absorb both active and reactive power from the power system and it is capable to inject these powers into this system when they are needed. While the SMES coil is discharging power into the system, this injected power is controlled by changing the duty cycle of the dc-dc chopper switches and its operation modes. SMES is always associated with power conversion system consisting of two identical converters. These converters are connected by a dc link capacitor and are used in the system to change between the alternative and the direct current, which is primarily required for the SMES unit task. This paper presents an efficient system based on the SMES unit to improve the transient stability by regulating the dc link voltage during the fluctuations in voltage or frequency after disturbances in a power system or at any rapid changes in the load size. The behavior of the system is tested with three faults/events in the power system, at the power supply, and at the loads side. The transient behavior of the designed system is observed with and without the SMES unit. The results show that the SMES system increases voltage stability across the dc link significantly whenever voltage and frequency in power supply are oscillating and rapid changes in the loads and disturbances in generation system occur.
Energy Conversion and Management, 1999
Superconducting magnetic energy storage (SMES) is known to be an excellent high-efficient energy storage device. This article is focussed on various potential applications of the SMES technology in electrical power and energy systems. SMES device founds various applications, such as in microgrids, plug-in hybrid electrical vehicles, renewable energy sources that include wind energy and photovoltaic systems, low-voltage direct current power system, medium-voltage direct current and alternating current power systems, fuel cell technologies and battery energy storage systems. An extensive bibliography is presented on these applications of SMES. Also, some conclusive remarks in terms of future perspective are presented. Also, the present ongoing developments and constructions are also discussed. This study provides a basic guideline to investigate further technological development and new applications of SMES, and thus benefits the readers, researchers, engineers and academicians who deal with the research works in the area of SMES.
Enhancement of Power System Transient Stability using Superconducting Magnetic Energy Storage
2017
This paper presents a study on SMES for power system transient stability enhancement. The transient stability of a power system is improved by PI controlled superconducting magnetic energy storage (SMES). The comparison of SMES and PI controlled SMES has been carried out. The simulation results show that under 3 phase fault, the performance of PI controlled SMES is better than SMES without PI controller. The proposed method provides a very simple and effective means of improvement of transient stability. IndexTerms—SMES, PI controller, Transient Stability ________________________________________________________________________________________________________
IEEE Transactions on Energy Conversion, 2011
Superconducting magnetic energy storage (SMES) systems are getting increasing interest in applications of power flow stabilization and control in the transmission network level. This trend is mainly supported by the rising integration of largescale renewable energy power plants into the high-power utility system and by major features of SMES units. In a SMES system, the power conditioning system (PCS) is the crucial component for controlling the power exchange between the superconducting coil and the ac system. The dynamics of the PCS directly influences the validity of the SMES in the dynamic control of the power system. This paper describes a novel PCS scheme of SMES to simultaneously perform both active and reactive power flow controls. Moreover, a detailed model of the SMES unit is derived and a three-level control scheme is designed, comprising a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent PCS dc bus capacitors' voltage drift/imbalance. The dynamic performances of the proposed systems are fully validated by computer simulation.
Journal of Clean Energy Technologies, 2015
A superconducting magnetic energy storage (SMES) system contains a high inducting coil and combines with power conversion system can act as a constant source of direct current. SMES unit connected to a power system is able to absorb and store both active and reactive power from this system and to inject these powers into the power system in the demand periods. These injected powers are controlled by changing both the duty cycle of the dc-dc chopper switches and its operation modes. This paper presents an efficient design based on an SMES unit controlled by the artificial neural network (ANN) to improve transient stability by regulating the dc link voltage and to damp the voltage and frequency fluctuations that are always associated with wind power generator. The authors propose interfacing the SMES between wind power farm and the power grid connected through the DC Link capacitor to rapidly stabilize the voltage and frequency fluctuations in the power system. The system behavior is tested with three different events for both voltage and frequency fluctuations of wind power generation with and without applying the SMES unit. The results show that both voltage and frequency stabilities are significantly increased when the SMES unit is applied in these three events.
Latin American Applied Research, 2004
At present, the advance of technology makes possible to include new energy storage devices in the electric power system. In addition, with the aid of power electronics devices, it is possible to independently exchange active and reactive power with the utility grid. This allows to perform a more effective primary frequency control and also to reduce the reserve power of generators. In this article, a model is presented of a Static Synchronous Compensator (STATCOM) with Superconducting Magnetic Energy Storage (SMES) used for controlling the primary frequency of the utility system. Moreover, a control algorithm for both devices is proposed. The performance of the presented STATCOM/SMES system is evaluated by using a test power system through the dynamic simulation in case of a tie-line tripping.