Modeling and Analysis of Variable Wind Speed Turbine System Using Back to Back Converter

Rotor blades are the most complex structural components in a wind turbine and are subjected to continuous cyclic loads of wind and self-weight variation. The structural maintenance operations in wind farms are moving towards condition based maintenance (CBM) to avoid premature failures. For this, damage prognosis with remaining useful life (RUL) estimation in wind turbine blades is necessary. Wind speed variation plays an important role influencing the loading and consequently the RUL of the structural components. This study investigates the effect of variable wind speed between the cutin and cut-out speeds of a typical wind farm on the RUL of a damage detected wind turbine blade as opposed to average wind speed assumption. RUL of wind turbine blades are estimated for different initial crack sizes using particle filtering method which forecasts the evolution of fatigue crack addressing the non-linearity and uncertainty in crack propagation. The stresses on a numerically simulated life size onshore wind turbine blade subjected to the above wind speed loading cases are used in computing the crack propagation observation data for particle filters. The effects of variable wind speed on the damage propagation rates and RUL in comparison to those at an average wind speed condition are studied and discussed.

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Adaptive Gains Control Scheme for PMSG-Based Wind Power Plant to Provide Voltage Regulation Service

Energies ◽

10.3390/en12040753 ◽

2019 ◽

Vol 12 (4) ◽

pp. 753 ◽

Cited By ~ 2

Author(s):

Jianfeng Dai ◽

Yi Tang ◽

Jun Yi

Keyword(s):

Wind Speed ◽

Power Plant ◽

Wind Power ◽

Reactive Power ◽

Voltage Regulation ◽

Wind Power Plant ◽

Control Scheme ◽

Power Capability ◽

Variable Wind ◽

Voltage Support

High-penetration wind power will count towards a significant portion of future power grid. This significant role requires wind turbine generators (WTGs) to contribute to voltage and reactive power support. The maximum reactive power capacity (MRPC) of a WTG depends on its current input wind speed, so that the reactive power regulating ability of the WTG itself and adjacent WTGs are not necessarily identical due to the variable wind speed and the wake effect. This paper proposes an adaptive gains control scheme (AGCS) for a permanent magnet synchronous generator (PMSG)-based wind power plant (WPP) to provide a voltage regulation service that can enhance the voltage-support capability under load disturbance and various wind conditions. The droop gains of the voltage controller for PMSGs are spatially and temporally dependent variables and adjusted adaptively depending on the MRPC which are a function of the current variable wind speed. Thus, WTGs with lower input wind speed can provide greater reactive power capability. The proposed AGCS is demonstrated by using a PSCAD/EMTDC simulator. It can be concluded that, compared with the conventional fixed-gains control scheme (FGCS), the proposed method can effectively improve the voltage-support capacity while ensuring stable operation of all PMSGs in WPP, especially under high wind speed conditions.

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Analysis of the Wind System Operation in the Optimal Energetic Area at Variable Wind Speed over Time

Sustainability ◽

10.3390/su11051249 ◽

2019 ◽

Vol 11 (5) ◽

pp. 1249 ◽

Cited By ~ 5

Author(s):

Ciprian Sorandaru ◽

Sorin Musuroi ◽

Flaviu Frigura-Iliasa ◽

Doru Vatau ◽

Marian Dordescu

Keyword(s):

Wind Speed ◽

Angular Velocity ◽

Optimal Operation ◽

Wind System ◽

Optimal Velocity ◽

Electric Generator ◽

Wind Speeds ◽

Power Point ◽

Variable Wind ◽

Over Time

Due to high mechanical inertia and rapid variations in wind speed over time, at variable wind speeds, the problem of operation in the optimal energetic area becomes complex and in due time it is not always solvable. No work has been found that analyzes the energy-optimal operation of a wind system operating at variable wind speeds over time and that considers the variation of the wind speed over time. In this paper, we take into account the evolution of wind speed over time and its measurement with a low-power turbine, which operates with no load at the mechanical angular velocity ωMAX. The optimal velocity is calculated. The energy that is captured by the wind turbine significantly depends on the mechanical angular velocity. In order to perform a function in the maximum power point (MPP) power point area, the load on the electric generator is changed, and the optimum mechanical velocity is estimated, ωOPTIM, knowing that the ratio ωOPTIM/ωMAX does not depend on the time variation of the wind speed.

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