Wave Power Output Smoothing through the Use of a High-Speed Kinetic Buffer

Abstract

In this paper, a new control strategy for power output smoothing in a hybrid wave energy installation coupled to a flywheel energy storage system (FESS) is proposed. The control scheme is composed by three stages: a wave generator clustering process at the farm connection point; a power filtering process; and the control of the flywheel energy storage in order to improve the power output of the hybrid wave farm. The proposed control is validated at the existing Lysekil Wave Energy Site located in Sweden, by using real generator measurements. Results show that the application of the flywheel energy storage system reduces the maximum peak power output from the wave energy installation by 85% and the peak/average power ratio by 76%. It is shown that the proposed system can reduce grid losses by 51%, consequently improving the energy efficiency of the power network. The application of the proposed control strategy allows the hybrid wave power plant to follow a power reference signal that is imposed by the grid operator. In addition, the study demonstrates that the application of the proposed control allows the hybrid wave power plant to follow a power reference signal that is imposed by the grid operator. In addition, the study demonstrates that the application of the proposed control enables a wave farm with flywheel energy storage to be a controllable, flexible resource in order to fulfill future grid code requirements for marine energy installations.

Performance Investigation of Switched Reluctance Motor Driven by Quasi-Z-Source Integrated Multiport Converter with Different Switching Algorithms

“…• Table 2 shows that algorithm#1 offers low torque ripple compared to the switching algorithm#2. This can be illustrated using the torque expression in (1). According to this expression, the torque is changed with the square of the phase current.…”

“…Switched reluctance machines (SRMs) are gaining attention for their utility in many applications, including renewable energy systems such as wind, wave and tidal energy systems, and electric vehicle (EV) drive systems [1][2][3][4]. This is due to their simple structure: both the stator and rotor are formed from salient poles, and neither permanent magnets nor conductors are required on the rotor.…”

“…where i ph is the phase current, L is the phase inductance, and θ is the stator phase angle with respect to the rotor. According to (1), the phase torque is positive during the positive slope of the phase inductance, negative during the negative slope of inductance, and zero during the constant inductance intervals. Therefore, to avoid motor operation under negative torque production, the off-going phase should be completely demagnetized as fast as possible before reaching the inductance negative slope region.…”

Dimensioning Methodology of an Energy Storage System Based on Supercapacitors for Grid Code Compliance of a Wave Power Plant

“…FESS have been studied together with a wave farm in [27] for controlling the power output of the complete installation, aiming for being compliant with the Nordic grid code. The authors in [27] develop a control based on three stages, achieving a reduction up to 85% in the power output peak. A control strategy is proposed for power smoothing in a hybrid wave energy plant.…”

Smart Sensors for Smart Grid Reliability

“…In this context, sensors and actuators (network breakers) are crucial players in smart grid management [4][5][6]. Employing sensors for real-time monitoring allows one to deal with the power management of distributed energy resources, such as distributed generators (DGs) [7] and electric vehicles [8], as well as to improve the smart grid's reliability [9].…”