Maximum power point tracking control for mechanical rectification wave energy converter

Abstract

As a clean and renewable energy, wave energy has abundant reserves, and its reasonable development and utilization can effectively alleviate the problems of energy shortage and environmental pollution. This paper proposes a mechanical rectification wave energy converter. The reciprocating linear motion of the buoy is directly converted into the rotary motion through the ball screw. The magnetic coupling force transmission system is adopted to ensure the sealing of the device. Using mechanical rectification mechanism to ensure the service life of the generator. In addition, a dynamic model of the mechanical rectification wave energy converter is established. Through simulation analysis, the curve of power with load resistance is obtained. And there is an optimal load resistance value corresponding to the maximum power in different wave conditions. In order to improve the power generation efficiency, the maximum power point tracking control algorithm is designed based on the admittance differentiation method. By controlling the duty cycle of the switch tube in the Buck-Boost chopper circuit, the variable load is realized, and then the maximum power point tracking control is realized. Finally, simulation analysis verifies the feasibility of the algorithm under different wave conditions.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Nonlinear Optimal Control for a PMLSG-VSC Wave Energy Conversion Unit

“…Overview of research results on control and optimization of WECS. [1][2][3][4] WECS consists of multi-phase AC generators and voltage source converters [5][6][7][8] Use of AC generators in connection to VSCs for wave energy conversion [9][10][11][12] Models and operation principles of generators and converters in WECS [13][14][15][16] Performance of wave-to-grid configurations of wave energy conversion units [17][18][19][20] Approaches to optimal control and optimized configuration of WECS [21][22][23] Control of converters for synchronizing WECS with the electricity grid [24][25][26][27] Control of power generation and power storage in wave energy conversion [28][29][30][31][32] Control for ensuring uninterrupted and maximized power supply from WECS [33][34][35][36][37] Modeling and control for optimizing power generation from WECS [38][39][40] New methods for nonlinear control of renewable energy systems and WECS The motion of the moving part (mover) of the PMSLG is given by: 𝑀𝑧̈= −𝑏 𝑔 𝑧̇− 𝑏 𝜔 𝑧̇− 𝑘 𝑠 𝑧 + 𝐹 𝑒 + 𝐹 𝑏𝑟 (1) where 𝑏 𝑔 𝑧̇ is the friction force that resists the motion of the moving part of the tubular PMLSG, 𝑏 𝑤...…”

“…Additionally, control of the integrated wave power generation systems, which comprise PMLSGs serially connected to VSCs, is a subtle task that should compensate for the complicated nonlinear dynamics and multivariable structure of these energy conversion units [24][25][26][27]. Among recent results in PMLSG and VSC-based wave power conversion systems, one can distinguish methods for maximizing the amount of wave power finally converted to exploitable electric power [28][29][30][31][32]. Several other results exist on the stabilization of WECs and on the VSC-based integration of these power units to the electricity grid [33][34][35][36][37].…”

Optimal efficiency point membership incorporating fuzzy logic and automatic control of various charging stages for electric vehicles

“…Especially in terms of battery technology, electric vehicle batteries made in China have occupied an important position in the international market due to their high energy density, long life and low cost. In recent years, the promotion of electric vehicles has become an important initiative for the development of new energy vehicles in the country, but the performance and safety of the car has also become an important issue affecting promotion (Xu et al, 2021). Wireless energy transmission technology is the core technology of wireless charging for electric vehicles, which has been applied in many fields (Nasab et al, 2023).…”

Maximal electric power generation from varying ocean waves with RLC-tuned reactive PTO force

“…To reveal the fundamental M-E dynamics, we assume that the whole WEC system is linear, the water is homogeneous, inviscid, irrotational and incompressible and the waves are sinusoidal, so the waves are describable by potential-flow theory [1], [3]; the added mass corresponding to the radiation force is constant [17], [23]; the shaft is rigid and lossless, and hence the buoy and translator (BT) and its added fluid mass move together as a single mass and all the masses are lumped into the system total mass M m . These assumptions encapsulate the essential traits of WECs and are commonly employed in the analysis and design of WECs [24], [25].…”

“…In attempts to directly maximize the WEC's electric power generation under varying waves, many electrical PTO methods have also been proposed, e.g., electric resistive latching [12], impedance tuning [13], damping control [14], reactive control [15], and maximum power point tracking [16], [17]. These methods use the WEC's generator to generate and control the PTO force while producing electricity, without additional devices and external power injection.…”