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In this paper, an innovative closed hydraulic wind turbine with an energy storage system is proposed. The hydraulic wind turbine consists of the wind rotor, the variable pump, the hydraulic bladder accumulator, the variable motor, and the synchronous generator. The wind energy captured by the wind rotor is converted into hydraulic energy by the var...
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Local development is aimed at achieving sustainability and energy independence with the use of indigenous resources, in this environment technologies that take advantage of wind energy are one of the most propitious in low wind speed. Since very remote times have been solving different problems in the isolated and rural areas, in the province of Ma...
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... (2) storing energy to enhance system efficiency or facilitate high-power transients (e.g., power recovery and regeneration in transmission systems for vehicles, construction machinery, wind turbines, etc.) [26][27][28]. In this study, a hydraulic equilibrium system, composed of an air bladder accumulator and a hydraulic rod, balances a portion of the gravitational torque on Joint 2. This arrangement alleviates the burden on the motor associated with Joint 2, thereby enhancing the robot's dynamic performance to a certain extent. ...
In recent decades, industrial robots have emerged as pivotal contributors to the global manufacturing landscape, revolutionizing various sectors through increased automation and efficiency. Simultaneously, the application of heavy-duty robots in heavy industries is gradually increasing. In this study, a self-developed heavy-duty robot is utilized for automated fiber placement (AFP), with the layup equipment integrated at the robot's end effector, weighing over one ton. To ensure the precision and efficiency of AFP, particular attention is given to the dynamic performance of the robot. The heavy-duty robot is equipped with a hydraulic equilibrium system to alleviate the gravitational load on the joint motors of both the robot body and the end effector. The hydraulic equilibrium system consists of a bladder accumulator and a hydraulic cylinder, introducing complexity to the robot dynamics. Therefore, establishing a dynamic model of the robot system and obtaining accurate dynamic parameters serve as the foundation for precise control of the robot, enabling the full utilization of its dynamic capabilities. In this paper, dynamics modeling of the hydraulic equilibrium system is performed based on the Maxwell model, and its dynamic parameters are identified using the CARAM model. Subsequently, the multi-body dynamic model of the robot is established, and an incremental identification algorithm for dynamic parameters is devised based on the characteristics of the robot structure. Additionally, to accurately identify dynamic parameters, an analysis of the robot drive mechanism is conducted to obtain the equivalent reduction ratio of the joints and the lever arm of the hydraulic equilibrium system. Furthermore, an equivalent friction model for the robot joints and screws is established.
... These air masses' motion can be found as a global phenomenon or a jet stream, as well as a regional phenomenon. Wind turbines utilize the energy of wind near the ground to generate electrical power (Alpi, 2019;Azrag et al., 2019;Bahmani et al., 2020;Faraji Nayeh et al., 2020;Garmat et al., 2020;Habibi et al., 2018;Hussein and Jaber, 2020;Jaber et al., 2012;Jahanshahi Zeitouni et al., 2020;Kakuya et al., 2020;Karami-Mollaee et al., 2022;Khurshid et al., 2022;Kim et al., 2019;Lackner and Rotea, 2011;Mirzaei et al., 2016;Moradi and Vossoughi, 2015;Movahhed Neya et al., 2022;Ngamroo, 2012;Nouriani and Moradi, 2022;Ossmann et al., 2021;Reddy and Hur, 2021;Soni, 2015;Tahir et al., 2019;Takatsu et al., 1991;van der Veen et al., 2013;Wei et al., 2018;Yang and He, 2020). In this area, the wind is subject to boundary layer conditions, due to the roughness of the ground, the wind stream flow near the ground is turbulent (Bahmani et al., 2020;Kakuya et al., 2020;Movahhed Neya et al., 2022;Nouriani and Moradi, 2022;Oubelaid et al., 2023). ...
... Although that method is good for the simple control system, there are quite a few attempts for wind turbine control. Byword, Wei et al. (2018) introduced a PID 600 kW hydraulic wind turbine model and control. To overcome the short time change of the wind speed, the wind power was transformed into hydraulic power and then the hydraulic system output was converted to electrical power during that short time. ...
The exploitation of nature to convert energy to electrical power is the most important rule in power generation. Wind energy is one of the most important of those energies that are widely available, and its use does not affect the environment significantly compared to fossil energy. On the other hand, and in recent times, researchers have made great efforts in the field of intelligent control andoptimization, which has led to great leaps in the development of these sciences. In this paper, a detailed study is proposed for filling the gaps and conducting an updating state-of-arts of the last pitch control methods in the wind turbine systems. The review is conducted by comparing the key requirements related to control, complexity, stability and speed rangeability. Furthermore, a new classification for the general controller is introduced according to the techniques. Several recommendations for future research related to the control and technical evaluation of wind energy are presented. In sum, the appropriate classification of such important issues and identification of their advantages and drawbacks may greatly contribute to find better solutions.
... An examp an experimental demonstration of an HST for community wind turbines is the regen tive test stand at the University of Minnesota [10]. The inclusion of an accumulato rapidly store and reuse energy has also been studied [11,12], but it requires a large a mulator [13,14] that could significantly increase the LCOE. ...
... An example of an experimental demonstration of an HST for community wind turbines is the regenerative test stand at the University of Minnesota [10]. The inclusion of an accumulator to rapidly store and reuse energy has also been studied [11,12], but it requires a large accumulator [13,14] that could significantly increase the LCOE. ...
... Similarly, NCF HST+GB = 37% (13) Assuming that the wind turbine has a twenty-year lifespan, the gearbox has a twentyyear service time without failure, and the HST pump needs to be rebuilt every ten years, a detailed calculation of the LCOE is made for the three designs: ...
This study investigates the potential improvement of a community wind turbine through replacing the conventional drivetrain with a hydrostatic transmission (HST). Conventional wind turbines use a fixed-ratio gearbox, a variable-speed induction generator, and power electronics to match the grid frequency. Because of unsteady wind, the reliability of the gearbox has been a major issue. An HST, a continuously variable transmission with a high power density, can replace a conventional transmission. The resulting wind turbine has the potential to offer the advantages of a lower cost, decreased weight, and increased reliability. For the application considered in this study, the main source of LCOE increase is due to the inefficiencies in the system. Even if the cost of the proposed HST transmission is free, because of inefficiency, the levelized cost of electricity will be higher than for a turbine with a conventional fixed-ratio gearbox. For the HST solution to be cost-competitive, increases in efficiency and reductions in cost are required.
... As an effective alternative, hydraulic transmission has drawn considerable attention in wind power research worldwide (Nikolic et al. 2016). Compared with the traditional gear wind turbine, the hydraulic wind turbine has the advantages of light weight, easy-to-implement stepless speed regulation, and hydraulic energy storage (Liu 2018). Therefore, it has become a research hotspot for wind power. ...
The wind turbine with digital hydraulic transmission can make the corresponding hydraulic pump work according to the wind speed, so that the hydraulic wind turbine can maintain high efficiency at the whole working wind speed. However, the switching of different displacement hydraulic pumps will cause a large flow impact on the hydraulic system of the wind turbine, affecting its working characteristics and the absorption of wind energy. Based on the analysis of the working principle of the digital hydraulic wind turbine, the scheme of a 5 MW wind turbine is designed and the AMESim model is established. The dynamic characteristics of the digital hydraulic wind turbine under two switching modes are compared. An advance valve closing control strategy is proposed to reduce the instantaneous flow impact. Simulation results show that the control strategy diminished the system flow shock by about 50% when switching the hydraulic pump. Finally, a hardware-in-loop system with a 5.5 kW digital hydraulic turbine is built to verify the effectiveness of the proposed control strategy. The research results provide a theoretical basis and technical reference for the efficient utilization of wind energy and stable operation of the digital hydraulic wind turbines.
... 1,2 At present, more than 341,331 horizontal axis wind turbines (HAWTs) are in operating condition all over the world. 3,4 The total rising capacities across the globe wind turbine (WT) installation systems were 9000 GW at the start of 2022. 5 To reduce power generation costs, load mitigation and control, replacement of the gear transmission system, and fault tolerance control are implemented to WT power generation systems. ...
... Apart from torque 19 and pitch control, 20 transmission control is also important to transfer the maximum power from WT to the generator and reduction of energy fluctuation. Wei et al. 3 reported 600 kW WT transmission system control. Some of the researchers reported transmission systems with energy storage 3,9,14 through the accumulator. ...
... Wei et al. 3 reported 600 kW WT transmission system control. Some of the researchers reported transmission systems with energy storage 3,9,14 through the accumulator. Another important aspect is to maximize 13 power tracking control of WTs for region II. ...
The wind power generation system plays a significant role in the power sector as it is an environment-friendly green power system, increasing power demand, and technological development in wind power systems. Wind turbine systems are exposed to the harsh environment with continuous variation of wind speed with gusts causing damage and failure in system components along with the fluctuation of generated power. The hydrostatic transmission system has become one of the promising solutions over the gear transmission system for transmitting power from the turbine rotor to the generator. Further to reduce power generation costs in wind power systems, a suitable control system with parametric uncertainty and system fault plays a significant role. In this study, the 5 MW wind turbine model has been developed with the combination of blade element momentum theory and the electrohydraulic transmission system model. Moreover, the wind turbine system model has been imposed fault in the pump of electrohydraulic transmission system. The proposed wind turbine system model has been validated with the existing result. The blade element momentum theory has been used to estimate the optimum pump turbine couple rotational speed for maximum power tracking. Double loop controller has been used for wind turbine power transmission system control. The first controller loop has been used for pump and wind turbine system speed control for maximum power tracking, as a passive fault tolerance controller and the second control loop for motor and generator system speed control to regulate the frequency of the generated power. Interval type 2-fuzzy proportional–integral–derivative controller are suitable for high degree of uncertain system like wind power system due to their footprint of uncertainties. Proper choice of footprint of uncertainty provides robust performance against uncertainties and dynamic performance. Hence, the primary and secondary controller has been developed as interval type 2-fuzzy proportional–integral–derivative with inertial weight local search–based teaching–learning-based optimization controller. The inertial weight local search–based teaching–learning-based optimization interval type 2-fuzzy proportional–integral–derivative controller performance has been studied with benchmark sinusoidal test signals. The proposed inertial weight local search–based teaching–learning-based optimization interval type 2-fuzzy proportional–integral–derivative controller performance has been also compared with conventional proportional–integral–derivative and interval type 2-fuzzy proportional–integral–derivative controller. The proposed system performance has been compared with contemporary reported digital hydrostatic transmission wind turbine system and recently reported controller with consideration of fault in the pump. The proposed inertial weight local search–based teaching–learning-based optimization interval type 2-fuzzy proportional–integral–derivative controller performance has been compared through integral absolute error with interval type 2-fuzzy proportional–integral–derivative controller and recently reported proportional–integral–derivative sliding mode controller obtained as 0.0016, 0.0029, and 0.0031, respectively.
... The flow equation for a variable displacement pump is determined by [26]: ...
... The wind turbine rotor is coaxially connected with the pump, so it was assumed that they had the same angular velocity, which is ω p = ω r . The torque balance equation between the wind turbine rotor and the pump is expressed as [26]: ...
... The hydraulic flow supplied to a variable hydraulic motor can be expressed as [26]: ...
Wind speed uncertainty and measurement noise affect the control effect in hydraulic wind turbine systems. This paper proposes a model predictive control (MPC) method with a dynamic Kalman filter (KF) based on a linear parameter-varying (LPV) model to address this problem. First of all, the LPV model for a nonlinear system of a hydraulic wind turbine is established using function substitution. Then, a LPV-based KF is introduced into the MPC to provide more precise estimated results and improve the anti-interference ability of the system. According to the current condition of the hydraulic wind turbine, the method updates the Kalman state estimator at each sampling instant and computes the optimal control input by solving a quadratic programming (QP) optimization problem. The performance and the efficiency of the proposed method is validated in simulation and compared with other methods.
... Walter Gil-Gonzaĺez et al. established a dynamic model for small hydro-power plant, and designed a controller based on passivity theory which better than PI controller (Gil-Gonzaĺez et al., 2020). Wei et al. proposed a new type of closed hydraulic wind turbine with an energy storage system and demonstrated the parametric design and modelling of a 600 kW hydraulic wind turbine using a Micon 600 kW wind turbine as an example (Wei et al., 2018). Chan Roh et al. established a mathematical model for the hydraulic system of floating wave energy converters, which included an accumulator, hydraulic motor, and generator. ...
With the increasing scarcity of energy in the world, energy has become an important part of restricting the development and application of traditional ocean profilers. The method of converting ocean thermal energy (OTE) into electrical energy through an energy conversion system is a solution. The model establishment and performance analysis of the energy conversion system are the basis of the ocean thermal profiler (OTP) design. The model and performance are affected by the coupling of multiple parameters, especially rotational speed and pressure. In this study, a universal parameterized model for multi-parameter coupling was proposed. System performance analysis based on experiments including load current, speed, mechanical efficiency and total efficiency was presented. After model parameter identification, the error of mechanical efficiency was within 5%; the total efficiency error was less than 12.8%, and the maximum efficiency point error didn’t exceed 2.21%. The results indicated that the parameterized model was satisfactory for the engineering applications and could guide the design of OTP.
... The ( curve depends on the pitch of the blades ( ) as well as the ratio between the equivalent wind speed v and the tipping speed of the blades called the tip speed ratio ( , [ ]). The electrical power ( is due to some losses in the wind turbine (Equation 8). (8) where, ( ) is the efficiency of the electrical power generation. ...
... The electrical power ( is due to some losses in the wind turbine (Equation 8). (8) where, ( ) is the efficiency of the electrical power generation. The power wind turbine ( is directly proportional to the cube of the wind speed, which can be formulated below (Equation 9). ...
... Based on the above equations (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12), it is now possible to set up the differential Equation 13, that describes a simple wind turbine model. ...
The development of control systems to improve efficiency requires accurate mathematical models. This article deals with
the modelling of two-mass variable speed wind turbine generators. A model design of a 3.5 MW vertically axial wind
generator and a mathematical model of an electromechanical system is considered in this article. Wind turbine
generators behave to have the most significant uncertainty, specified the possibility for nonlinear behaviour. The main
focus is on structural aerodynamics, including the forcing and motion of the rotating parts of the turbine. The turbine’s
critical structural aerodynamics and mechanical components are the blade pitch actuators, drive shaft actuators, and
turbine specifications. With an accurate wind turbine model, the control engineers will design control systems to reduce
loads, increase the operating lifetime, and increase electrical power. Methods of linearization about operating points have
been proposed to enable an efficient control system design. The results show that the model can be used in different
strategies evaluation.
... Other researchers have proposed different variations on the hydraulic turbine idea (also known as a hydrostatic drivetrain). The components and control of the hydraulic system vary, but often include a variable displacement motor and synchronous generator, while some also include a variable displacement pump and hydraulic accumulator [19,20]. With a variable pump and variable motor, two closed loop ...
... In-Plane control systems can track optimal tip-speed-ratio and also meet synchronous generator requirements [19]. While the hydraulic transmission tends to be less efficient than a geared transmission, using a constant speed generator can remove the need for power electronic converters and improve efficiency [21,22]. ...
... Different methods for application and control of energy storage in the hydraulic transmission have also been considered, both to increase energy production and/or smooth energy output. These systems are typically short-term energy storage using a hydraulic accumulator which focuses on smoothing fluctuations in power production due to turbulence [19,22,24,[30][31][32]. An innovative control system design reported in Dutta et al. and further investigated in Mohr et al. allows the turbine to generate slightly more than rated power in Region 2.5 to capture some of the turbulent energy fluctuations, with a focus on fluctuations on the 1-minute time scale [22,24,32]. ...
A new super-rated method of wind turbine control is proposed for operation between rated and cut-out wind speeds, in conjunction with integrated energy storage, that may allow dramatically increased power capture as well as improved energy dispatchability without increasing turbine size or generator size. In the proposed system, a hydraulic transmission is used decouple the wind turbine rotor from the electric generator, allowing for mechanical energy storage to be integrated into the system before the generator. Rather than the conventional Region 3 control, the new super-rated Region 3+ operation allows the rotor to generate additional power above the rated power limit and store that additional power for later regeneration. In this Region 3+ operation, the limit on operation is based on rotor thrust loads (instead of rotor power) so that power can increase with increasing wind speed. A case study with the NREL 5 MW reference turbine in steady Class I winds showed that super-rated operation could increase annual power production by 23% (including hydraulic transmission storage losses), without increasing mean out-of-plane blade loads, rotor size, or generator power. In addition, this new operation for this case increases the capacity factor from 53% to 66%, which increases power levelization. However, a wide array of component design issues must be addressed (especially for the hydraulic drivetrain) to determine if this potential can be realized.
... The research in the development of effective methods and electronics such as high-quality electric hubs and active power filters for the smooth integration of wind energy output with the grids is still a demanding area ( Perera et al., 2017;Tareen et al., 2017). The energy storage systems compatible with wind energy farms are also being developed ( Hemmati, 2017;Ma et al., 2017;Wei et al., 2018). Apart from all these current developments, the establishment of reliable models and software for the smooth functioning of each unit and various components of wind energy farms is a necessity. ...
The energy demand is rapidly increasing globally, and extensive use of conventional energy resources is causing global warming, environmental pollution, health issues, etc. Fossil energy resources are declining rapidly, while wind energy is a cost-effective and promising energy source amongst renewable energy resources. The understanding and development of wind energy technologies is thus a necessity in the field of green energy production. This chapter provides exposure to the wind energy conversion systems along with the current status and future perspective of wind energy technologies. Furthermore, the socio-economic and environmental challenges of wind energy systems are also discussed in this chapter.
