Load Frequency Control of Three area Multi-Unit Deregulated Power System with FOSMC and Performance analysis using Regulation constant

This paper presents three area multi-unit Deregulated Power System (DPS) for Load Frequency Control (LFC) using Fractional Order Sliding Mode Controller (FOSMC) along with Thyristor Controlled Phase Shifters (TCPS) and Superconducting Magnetic Energy Storage (SMES) combination. The FOSMC can be used to overcome nonlinearities and uncertainties of the system for bilateral and unilateral transactions under different Step Load Perturbations (SLPs). The deregulated power system performance is analyzed for different Regulation constants (R) such as 1.8, 2.4 and 3.0. For stabilization of oscillations in frequency and to stabilize the deregulated power system dynamically for different SLPs, TCPS is incorporated with the tie line in series and SMES is used as an energy storage unit. The dynamic responses of LFC problems have been simulated and analyzed with MATLAB/Simulink-based computer simulations. Further simulation results have also been tabulated as a comparative performance with respect to peak overshoot and settling time.&nbsp

Microstructures and Toughening of TiC-TiB 2

Micro-nanocrystalline microstructures which are characterized by TiB2 platelets of the average thickness close to or smaller than 1 μm can be achieved in nearly full-density solidified TiC-TiB2 ceramic composites with Cr-based alloy phases by combustion synthesis in ultra-high gravity field of 2500 g. The filler phases in ceramic composites are actually Cr-based alloy with a little solidified solution of Ni atoms and Al atoms. The hardness, flexural strength, and fracture toughness of the materials are 18.5 ± 1.5 GPa, 650 ± 35 MPa, and 16.5 ± 1.5 MPa⋅m0.5, respectively. The improved fracture toughness of TiC-TiB2 ceramic composites results from crack deflection, crack bridging, and pull-out by a large number of fine TiB2 platelets and plastic deformation with some Cr-based alloy phases

Quadrotor Aggressive Deployment, Using a Quaternion-based Spherical Chattering-free Sliding-mode Controller

International audienceThis paper introduces a non-conventional approach for autonomous multi-rotor UAV deployment, in which a quadro-tor is aggressively launched through the air with its motors turned off. A continuous quaternion attitude trajectory is proposed to safely recover the vehicle into hover mode. Then, an operator then could take the command or continue a desired mission in autonomous mode. The controller is a chattering-free sliding mode algorithm based on the geometrical properties of quaternions and axis-angle rotations. Lyapunov theory is used to analyze the system stability. The proposed methodology is validated in real world indoor and outdoor experiments

Research and Implement of PMSM Regenerative Braking Control for Electric Vehicle

As the society pays more and more attention to the environment pollution and energy crisis, the electric vehicle (EV) development also entered in a new era. With the development of motor speed control technology and the improvement of motor performance, although the dynamic performance and economical cost of EVs are both better than the internal-combustion engine vehicle (ICEV), the driving range limit and charging station distribution are two major problems which limit the popularization of EVs. In order to extend driving range for EVs, regenerative braking (RB) emerges which is able to recover energy during the braking process to improve the energy efficiency. This thesis aims to investigate the RB based pure electric braking system and its implementation. There are many forms of RB system such as fully electrified braking system and blended braking system (BBS) which is equipped both electric RB system and hydraulic braking (HB) system. In this thesis the main research objective is the RB based fully electrified braking system, however, RB system cannot satisfy all braking situation only by itself. Because the regenerating electromagnetic torque may be too small to meet the braking intention of the driver when the vehicle speed is very low and the regenerating electromagnetic torque may be not enough to stop the vehicle as soon as possible in the case of emergency braking. So, in order to ensure braking safety and braking performance, braking torque should be provided with different forms regarding different braking situation and different braking intention. In this thesis, braking torque is classified into three types. First one is normal reverse current braking when the vehicle speed is too low to have enough RB torque. Second one is RB torque which could recover kinetic energy by regenerating electricity and collecting electric energy into battery packs. The last braking situation is emergency where the braking torque is provided by motor plugging braking based on the optimal slip ratio braking control strategy. Considering two indicators of the RB system which are regenerative efficiency and braking safety, a trade-off point should be found and the corresponding control strategy should be designed. In this thesis, the maximum regenerative efficiency is obtained by a braking torque distribution strategy between front wheel and rear wheel based on a maximum available RB torque estimation method and ECE-R13 regulation. And the emergency braking performance is ensured by a novel fractional-order integral sliding mode control (FOISMC) and numerical simulations show that the control performance is better than the conventional sliding mode controller