Optimal control of the power ramp rate with flicker mitigation for directly grid connected wind turbines

In this paper, a detailed mathematical optimization model of electrolyzer/fuel cell technology connected to the grid through limited rating converters is developed. The model is so defined that it can tackle voltage fluctuation and meet the power ramp rate limitations inflicted by integration of constant-speed wind turbines at the Point of Common Coupling. The flicker mitigation and power ramp rate control problem in the presence of wind generation and variable electrical loads is defined as a nonlinear constrained optimization problem, in which voltage fluctuation is minimized as the objective function and the power ramp rate limitations are respected by the defined real-time ramp rate constraint. The problem is solved using the sequential quadratic programming method, which is a fast solver, by adjusting suitable initial points to be appropriate for real-time applications. The simulation results validate the efficiency of the proposed method and show dramatic improvement in flicker mitigation, power ramp rate control, and system rating reduction in comparison with the proportional–integral control method that was developed in previous studies.

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Design of Supervisory Control for Speed Control of Wind Turbine using Torque-Control Method Based on Buck Converter

E3S Web of Conferences ◽

10.1051/e3sconf/202019000019 ◽

2020 ◽

Vol 190 ◽

pp. 00019

Author(s):

Katherin Indriawati ◽

Choirul Mufit ◽

Andi Rahmadiansah

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Supervisory Control ◽

Control Method ◽

Speed Control ◽

Buck Converter ◽

Torque Control ◽

Control Mode ◽

Rotor Speed ◽

Integral Control

The variation of wind speed causes the electric power generated by the turbine also varies. To obtain maximum power, the rotor speed of wind turbines must be optimally rated. The rotor speed can be controlled by manipulating the torque from the generator; this method is called Torque Control. In that case, a DC-DC converter is needed as the control actuator. In this study, a buck converter-based supervisory control design was performed on the Horizontal-axis wind turbines (HAWT). Supervisory control is composed of two control loops arranged in cascade, and there is a formula algorithm as the supervisory level. The primary loop uses proportional control mode with a proportional gain of 0.3, whereas in the secondary loop using proportional-integral control mode with a proportional gain of 5.2 and an integral gain of 0.1. The Supervisory control has been implemented successfully and resulted in an average increase in turbine power of 4.1 % at 5 m s–1 and 10.58 % at 6 m s–1 and 11.65 % at 7 m s–1, compared to wind turbine systems without speed control.

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Ramp rate control and voltage regulation for grid directly connected wind turbines

2008 IEEE Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century ◽

10.1109/pes.2008.4596329 ◽

2008 ◽

Cited By ~ 7

Author(s):

Ali H. Kasem ◽

Ehab F. El-Saadany ◽

Hassan H. El-Tamaly ◽

Mohamed A. A. Wahab

Keyword(s):

Wind Turbines ◽

Rate Control ◽

Voltage Regulation ◽

Ramp Rate

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A rate control method with preanalysis for real-time MPEG-2 video coding

Proceedings 2001 International Conference on Image Processing (Cat. No.01CH37205) ◽

10.1109/icip.2001.958164 ◽

2002 ◽

Cited By ~ 1

Author(s):

Y. Yokoyama ◽

S. Nogaki

Keyword(s):

Video Coding ◽

Real Time ◽

Rate Control ◽

Control Method

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Comparative and Cost Analysis of a Novel Predictive Power Ramp Rate Control Method: A Case Study in a PV Power Plant in Puerto Rico

Applied Sciences ◽

10.3390/app11135766 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5766

Author(s):

Juan F. Patarroyo-Montenegro ◽

Jesus D. Vasquez-Plaza ◽

Omar F. Rodriguez-Martinez ◽

Yuly V. Garcia ◽

Fabio Andrade

Keyword(s):

Puerto Rico ◽

Power Plant ◽

Control Strategy ◽

Rate Control ◽

Control Method ◽

Real Data ◽

Control Methods ◽

Ramp Rate ◽

Proposed Model ◽

One Year

One of the most important aspects that need to be addressed to increase solar energy penetration is the power ramp-rate control. In weak grids such as the one found in Puerto Rico, it is important to smooth power fluctuations caused by the intermittence of passing clouds. In this work, a novel power ramp-rate control strategy is proposed. Additionally, a comparison with some of the most common power ramp-rate control methods is performed using a proposed model and real solar radiation data from the Coto Laurel photovoltaic power plant located in Ponce, Puerto Rico. The proposed model was validated using one-year real data from Coto Laurel. The power ramp-rate control methods were compared in real-time simulations using the OP5700 from Opal-RT Technologies considering power ramp rate fluctuations, power ramp-rate violations, fluctuations in the state-of-charge, among other indicators. Moreover, the proposed power ramp-rate control strategy, called predictive dynamic smoothing was explained and compared. Results indicate that the predictive dynamic smoothing produced a considerably reduced Levelized Cost of Storage compared to other power ramp-rate control methods and provided a higher lifetime expectancy for lithium batteries.

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