The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Power frequency transformer is necessary when doubly fed induction generator (DFIG) connects with high-voltage ac grid. However power frequency transformer possesses many undesirable properties such as bulky size, environmental concerns. Additionally, the wind farms need reactive power compensation, such as static synchronous compensator (STATCOM). In this paper, the DFIG converter system with integrated...
A quick analysis approach based on Pontryagin principle is proposed to calculate the maximum cross-range, and the lateral accessible region in the new redefined coordinate is analyzed. The order and non-linearity of the point-mass motion function is reduced by coordinate transformation and replacing the independent variable, the trajectory optimization is cast as an optimal control problem, then the...
A method for Unmanned Surface Vehicle (USV) to follow linear path is proposed, considering both position error and course error. Based on dynamic model of the USV which is thrust with twin fixed propellers driven by DC electric motors, Cross Track Error and Line of Sight are combined into DIDO controller based on PD. The simulation experiment is conducted and compared with the method using Cross Track...
Previous works have shown a linear anode spot formation threshold current (I\(_{\rm th}\) ) dependence on the critical axial magnetic field (AMF), \({\textit {B}}^{\rm crit}_{\rm AMF}\) , in a vacuum under applied AMFs of up to \(\sim 110\) mT. However, the effects of the contact design parameters (e.g., contact diameter, contact gap, and contact material) on this dependence have not yet been...
As a functional material of the enhanced cooling, porous matrix has been widely used in the environments concerned with very high temperature. Through the pores of the porous matrix, the flowing coolant absorbs and takes away the heat inside the matrix to achieve the thermal protection of high temperature structures. In the past investigations on the permeability of porous materials, experiments and...
This paper discusses the constraints of coplanar points in perspective projection, based on which a new method to calibrate lens distortion is presented. Stem from the concept of center line related to Ponceletpsilas theorem on projective geometry, an equation of the center line is derived algebraically, from which some useful properties of the center line are deduced. These properties constitute...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.