Zengin S.,Ege University |
Deveci F.,Ege University |
Deveci F.,Electronic Control Systems |
Boztepe M.,Ege University
IEEE Transactions on Power Electronics | Year: 2013
Electrolytic capacitors as a decoupling reservoir restrict the lifetime of photovoltaic (PV) microinverters. This has led to the development of several improved decoupling circuits that can reduce the capacitor value to allow the use of nonelectrolytic types. In this paper, the minimum decoupling capacitor value for the proper operation of discontinuous conduction mode flyback PV microinverters is analyzed by taking into account the total harmonic distortion (THD) and PV power utilization ratio. The results presented show that the decoupling capacitor value influences the THD more than PV power utilization. A decoupling capacitor selection method for single-stage and two-stage flyback inverters is proposed. Experimental results obtained on an 80-W test bench are presented. © 1986-2012 IEEE.
Lanzon A.,University of Manchester |
Lanzon A.,Electronic Control Systems |
Freddi A.,Marche Polytechnic University |
Longhi S.,Marche Polytechnic University
Journal of Guidance, Control, and Dynamics | Year: 2014
In this paper, the problemof designingacontrol lawincase ofrotor failure inquadrotor vehiclesis addressed. First, a nonlinear mathematical model for a quadrotor vehicle is derived, which includes translational and rotational dynamics. Then a robust feedback linearization controller isdeveloped, which sacrifices the controllability ofthe yaw state due to rotor failure to linearize the closed-loop system around a working point, where roll and pitch angles are zero and the angular speed around the vertical axis is a nonzero constant. An H∞ loop shaping technique is adopted to achieve regulationofthese variables around the chosen working point. Finally,anouter loopisproposed for achieving control of the linear displacement under the assumption of small angles approximation for the pitch and roll angles. The proposed control strategy allows the vehicle to use the remaining three functional rotors to enter a constant angular speed around its vertical axis, granting stability and representing an effective way to deal with a rotor failure in quadrotor vehicles. Copyright © 2013 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.
Ding Z.,Electronic Control Systems
International Journal of Control | Year: 2014
This paper deals with consensus control of a class of nonlinear systems with Lipschitz nonlinearities. Certain features of the Laplacian matrix are explored in the real Jordan form to identify conditions for global consensus control. Under the identified conditions, consensus control and stability of the proposed control are analysed in time domain through Lyapunov functions in real domain. The proposed control uses relative state information of the system. A simulation study is included to demonstrate the proposed control designs with some simulation results shown. © 2014 © 2014 Taylor & Francis.
Filipiak J.,Electronic Control Systems |
Solarz L.,Military University of Technology |
Steczko G.,Electronic Control Systems
Sensors | Year: 2011
In the paper a feasibility study on the use of surface acoustic wave (SAW) vibration sensors for electronic warning systems is presented. The system is assembled from concatenated SAW vibration sensors based on a SAW delay line manufactured on a surface of a piezoelectric plate. Vibrations of the plate are transformed into electric signals that allow identification of the sensor and localization of a threat. The theoretical study of sensor vibrations leads us to the simple isotropic model with one degree of freedom. This model allowed an explicit description of the sensor plate movement and identification of the vibrating sensor. Analysis of frequency response of the ST-cut quartz sensor plate and a damping speed of its impulse response has been conducted. The analysis above was the basis to determine the ranges of parameters for vibrating plates to be useful in electronic warning systems. Generally, operation of electronic warning systems with SAW vibration sensors is based on the analysis of signal phase changes at the working frequency of delay line after being transmitted via two circuits of concatenated four-terminal networks. Frequencies of phase changes are equal to resonance frequencies of vibrating plates of sensors. The amplitude of these phase changes is proportional to the amplitude of vibrations of a sensor plate. Both pieces of information may be sent and recorded jointly by a simple electrical unit. © 2011 by the authors; licensee MDPI, Basel, Switzerland.
Sakata S.,Electronic Control Systems |
Ashida F.,Electronic Control Systems |
Tanaka H.,The University of Shimane
Computer Methods in Applied Mechanics and Engineering | Year: 2010
This paper discusses stabilization of an optimization procedure to determine an appropriate semivariogram parameter using the empirical semivariogram for Kriging-based approximation. From a viewpoint of a computational cost for constructing a surrogate model, a semivariogram fitting approach using the empirical semivariogram can be usable for the parameter estimation of a semivariogram function. However, instability of the optimization procedure for determination of the semivariogram parameter may be observed in some cases and it causes to generate an invalid surrogate model. For this problem, a simple technique for stabilization of the optimization for the parameter determination is proposed in this paper. The proposed approach employs a normalization technique of input data with respect to values of variables and an objective function. The proposed method is applied to some numerical examples, and the numerical results illustrate validity and effectiveness of the proposed method. © 2010 Elsevier B.V.