Mihaela Codruta Ancuti

Optimizing Wind Energy Capture_OPTIM

In the last decade, modern vehicles have become very complex, being equipped with embedded electronic systems which include more than a thousand of electronic control units (ECUs). Therefore, it is mandatory to analyze the potential risk of automotive systems failure because it could have a significant impact on humans’ safety. This paper proposes a novel, functional safety concept at the power management level of a system basis chip (SBC), from the development phase to system design. In the presented case, the safety-critical application is represented by a powertrain transmission electronic control unit. A step-by-step design guideline procedure is presented, having as a focus the cost, safety, and performance to obtain a robust, cost-efficient, safe, and reliable design. To prove compliance with the ISO 26262 standard, quantitative worst-case evaluations of the hardware have been done. The assessment results qualify the proposed design with automotive safety integrity levels (ASIL, up to ASIL-D). The main contribution of this paper is to demonstrate how to apply the functional safety concept to a real, safety-critical system by following the proposed design methodology.

The wind turbine’s operation is affected by the wind speed variations, which cannot be followed by the wind turbine due to the large moment of the power plant’s inertia. The method proposed in this paper belongs to the wind turbine power curves (WTPC) approach, which expresses the power curve of the permanent magnet synchronous generator (PMSG) by a set of mathematical equations. The WTPC research papers published before now have not taken into consideration the total power plant inertia at time-variable wind speeds, when the wind turbine’s optimal operation is very difficult to be reached, and its efficiency is thus threatened. The study is based on a wind turbine having a large moment of total inertia, and demonstrates, through extensive simulation results, that the optimal values of the PMSG’s power can be determined based on the kinetic motion equation. This PMSG’s optimal power represents an ideal time-varying curve, and the wind turbine should be controlled so as to closely follow it. For this purpose, proportional integral (PI) and proportional integral derivative (PID) type-based control methods were implemented and analyzed, so that the PMSG’s power oscillations could be reduced, and the PMSG’s angular speed value made comparable to the optimal one, meaning that the wind turbine operates within the optimal operation area, and is efficient. The simulations are actually the numerical solutions obtained by using the Scientific Workplace simulation environment, and they are based on the wind speed measurements collected from a wind farm located in Dobrogea, Romania.