Modeling and Lyapunov-designed based on adaptive gain sliding mode control for wind turbines

In this paper, modeling and the Lyapunov-designed control approach are studied for the Wind Energy Conversion Systems (WECS). The objective of this study is to ensure the maximum energy production of a WECS while reducing the mechanical stress on the shafts (turbine and generator). Furthermore, the proposed control strategy aims to optimize the wind energy captured by the wind turbine operating under rating wind speed, using an Adaptive Gain Sliding Mode Control (AG-SMC). The adaptation for the sliding gain and the torque estimation are carried out using the sliding surface as an improved solution that handles the conventional sliding mode control. Furthermore, the resultant WECS control policy is relatively simple, meaning the online computational cost and time are considerably reduced. Time-domain simulation studies are performed to discuss the effectiveness of the proposed control strateg

Experimental Validation of a Marine Current Turbine Simulator: Application to a Permanent Magnet Synchronous Generator-Based System Second-Order Sliding Mode Control

This paper deals with the experimental validation of a Matlab-Simulink simulation tool of marine current turbine (MCT) systems. The developed simulator is intended to be used as a sizing and site evaluation tool for MCT installations. For that purpose, the simulator is evaluated within the context of speed control of a permanent magnet synchronous generatorbased (PMSG) MCT. To increase the generated power, and therefore the efficiency of an MCT, a nonlinear controller has been proposed. PMSG has been already considered for similar applications, particularly wind turbine systems using mainly PI controllers. However, such kinds of controllers do not adequately handle some of tidal resource characteristics such as turbulence and swell effects. Moreover, PMSG parameter variations should be accounted for. Therefore, a robust nonlinear control strategy, namely second-order sliding mode control, is proposed. The proposed control strategy is inserted in the simulator that accounts for the resource and the marine turbine models. Simulations using tidal current data from Raz de Sein (Brittany, France) and experiments on a 7.5-kW real-time simulator are carried out for the validation of the simulator.Thèse financée par Brest Métropole Océan

Experimental Validation of a Marine Current Turbine Simulator: Application to a Permanent Magnet Synchronous Generator-Based System Second-Order Sliding Mode Control

This paper deals with the experimental validation of a Matlab-Simulink simulation tool of marine current turbine (MCT) systems. The developed simulator is intended to be used as a sizing and site evaluation tool for MCT installations. For that purpose, the simulator is evaluated within the context of speed control of a permanent magnet synchronous generatorbased (PMSG) MCT. To increase the generated power, and therefore the efficiency of an MCT, a nonlinear controller has been proposed. PMSG has been already considered for similar applications, particularly wind turbine systems using mainly PI controllers. However, such kinds of controllers do not adequately handle some of tidal resource characteristics such as turbulence and swell effects. Moreover, PMSG parameter variations should be accounted for. Therefore, a robust nonlinear control strategy, namely second-order sliding mode control, is proposed. The proposed control strategy is inserted in the simulator that accounts for the resource and the marine turbine models. Simulations using tidal current data from Raz de Sein (Brittany, France) and experiments on a 7.5-kW real-time simulator are carried out for the validation of the simulator.Thèse financée par Brest Métropole Océan

Enhancement of Solar PV Panel Using Single Integral Sliding Mode MPPT Control

The maximum power extraction using single integral sliding mode control scheme is established from the sliding mode control scheme. The sliding mode control (SMC) scheme extracts the maximum power during the partial shading weather conditions using the effective selection sliding surface duty cycle ratio in combination of dc/dc boost converter. This dynamic operation of sliding surface selection operation in partial shading conditions aids to enhance the solar panel efficiency compared to the other existing MPPT schemes. The effective dynamic operation of sliding surface mode control is designed using feedback loop control scheme to diminish the steady state voltage error of the solar panel, further to obtain the higher sliding duty cycle ratio. The dc-to-dc boost converter is made active using sliding duty cycle ratio as input gate signal boost converter switch. Hence, higher efficiency attains at higher sliding surface duty ration. This sliding surface duty ratio is limited in sliding mode MPPT control scheme and requires the necessary advancements to achieve the maximum duty cycle ratio. The single integral sliding mode control scheme offers the maximum duty cycle ratio compared to sliding mode control scheme. Therefore, this paper discusses the single integral sliding mode MPPT control scheme. The proposed method employs the effective dynamic sliding operation using integrated steady state voltage error signal and allows to nullify the lacuna of maximum sliding duty cycle ratio. Also, the projected SISMC scheme improves the effective dynamic sliding surface switching operations compared to sliding control scheme. This allows the system to be stable and reliable switching operations. To validate the proposed MPPT control scheme the MATLAB / Simulink model was designed and verified. Also, the SMC scheme was designed and compared with the present method

Enhancement of Solar PV Panel Using Single Integral Sliding Mode MPPT Control

The maximum power extraction using single integral sliding mode control scheme is established from the sliding mode control scheme. The sliding mode control (SMC) scheme extracts the maximum power during the partial shading weather conditions using the effective selection sliding surface duty cycle ratio in combination of dc/dc boost converter. This dynamic operation of sliding surface selection operation in partial shading conditions aids to enhance the solar panel efficiency compared to the other existing MPPT schemes. The effective dynamic operation of sliding surface mode control is designed using feedback loop control scheme to diminish the steady state voltage error of the solar panel, further to obtain the higher sliding duty cycle ratio. The dc-to-dc boost converter is made active using sliding duty cycle ratio as input gate signal boost converter switch. Hence, higher efficiency attains at higher sliding surface duty ration. This sliding surface duty ratio is limited in sliding mode MPPT control scheme and requires the necessary advancements to achieve the maximum duty cycle ratio. The single integral sliding mode control scheme offers the maximum duty cycle ratio compared to sliding mode control scheme. Therefore, this paper discusses the single integral sliding mode MPPT control scheme. The proposed method employs the effective dynamic sliding operation using integrated steady state voltage error signal and allows to nullify the lacuna of maximum sliding duty cycle ratio. Also, the projected SISMC scheme improves the effective dynamic sliding surface switching operations compared to sliding control scheme. This allows the system to be stable and reliable switching operations. To validate the proposed MPPT control scheme the MATLAB / Simulink model was designed and verified. Also, the SMC scheme was designed and compared with the present method

Integral sliding-mode controller for maximum power point tracking in the grid-connected photovoltaic systems

The output power generated in the photovoltaic modules depends both on the solar radiation and the temperature of the solar cells. To maximize the efficiency of the system, it is required to monitor the maximum power point of the photovoltaic system. For this purpose, monitoring the maximum power point (MPPT) of photovoltaic systems should be as quick and accurately as possible for increasing energy production, which ultimately increases the cost-efficiency of the photovoltaic system. This paper proposes a new approach for MPPT) using the concept of the integral sliding mode controller (ISMC) to ensure fast and precise monitoring of the peak power. The performance of the ISMC is significantly influenced by the choice of the sliding surface. To assess the reliability ISMC control, the results have been compared with those of a PI controller. The results obtained are used to evaluate the performance of the ISMC strategy under different climatic conditions. Finally, the effectiveness of the proposed solution is confirmed using simulations in PSIM tools and experimental results were used to evaluate the effectiveness of the proposed approach

A Sliding Mode Control for a Sensorless Tracker: Application on a Photovoltaic System

The photovoltaic sun tracker allows us to increase the energy production. The sun tracker considered in this study has two degrees of freedom (2-DOF) and especially specified by the lack of sensors. In this way, the tracker will have as a set point the sun position at every second during the day for a period of five years. After sunset, the tracker goes back to the initial position (which of sunrise). The sliding mode control (SMC) will be applied to ensure at best the tracking mechanism and, in another hand, the sliding mode observer will replace the velocity sensor which suffers from a lot of measurement disturbances. Experimental measurements show that this autonomic dual axis Sun Tracker increases the power production by over 40%

GWO-super-twisting integral sliding mode control of 60 KW PV system based on interleaved boost converter

The energy provided by the PV system is strongly influenced by climatic conditions such as solar radiation and cell temperature. A suitable DC /DC converter and a robust control strategy combined with the maximum power point tracking (MPPT) algorithm are required to harness the maximum power of the panel. This paper proposes a super-twisting integral sliding mode control (ST-ISMC) for four legs interleaved boost converter (FLIBC) as an interface to the MPPT algorithm for a 60 KW PV system. The FLIBC has been used to overcome the drawbacks of the conventional boost converter (CBC). The ST-ISMC is proposed to maintain the PV voltage track the reference provided by the MPPT algorithm and ensure the equal sharing of input current between legs. The controller gains of the proposed ST-ISMC have been calculated using the grey wolf optimization algorithm for better performance. The simulation results prove the excellent performance of the proposed controller over the conventional controller