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How to design an optimal mixed H2/H∞ robust FID controller for a complex control system is of great practical importance, but it is still an open issue. From the perspective of evolutionary algorithm, this paper formulates this issue firstly as a typical constrained optimization problem by minimizing a weighted objective function consisting of the robust stability performance, disturbance attenuation...
A simple, self-starting and stable dual-wavelength-comb mode-locked fiber laser is realized with a dual-mode-fiber-based filter. The cost-effective, multimode interference fiber filter with low spectral modulation depth enables relatively wide spectral bandwidths in the mode-locking windows.
Dead-time effect of dual active bridge (DAB) DC-DC converter is usually out of consideration in traditional optimized strategies, causing the deviation of the theoretical and actual results. In this paper, the current stress model of DAB with dead-time effect is given, and combining the transmission power model, a current-stress-optimized strategy is proposed. Meanwhile, the corresponding control...
Nowadays, research on the reliability improvement of T-type three-level inverters is studied as an important issue. In this paper, a novel fault tolerant control strategy based on model predictive control (MPC) is proposed for open-circuit faults in switch devices. When an open-circuit fault occurs to neutral-point switches, the impossible switching states of zero- and small-voltage vectors should...
This paper studies the use of consensus control to coordinate distributed Electric Springs (ES) in addressing the voltage regulation and reactive power sharing problems in an isolated microgrid. Consensus control can ensure the collective operation of multiple ESs and a fair sharing of voltage regulation task among them. Low bandwidth communication infrastructure is sufficient for consensus control...
Because of the differences in line impedances, parallel inverters with conventional droop control will have huge circulating current, which does not flow through the loads. To mitigate the circulating current, the research in this paper finds out that parallel-operated inverters should have the impedance in inverse proportion to their capacities, which is difficult to realize in practice. To meet...
This paper is concerned with the stochastic stabilization problem of observer-based output feedback control for sampled-data system. Different from most previous studies, we assume stochastic sampling and packet dropout may occur simultaneously. The packet dropouts lost in both the sensor-controller (S/C) and controller-actuator (C/A) channels are modelled by two mutually independent stochastic variables...
The navigation relayed by multiple stations (NRMS) is an advanced cooperative navigation technology which relies on multiple different stations to sequentially guide a vehicle to its destination. This paper addresses the optimal path planning problem for the vehicle navigated by the NRMS technology (OPP-V-NRMS) which is a challenging hierarchical mixed-variable constrained optimization problem involving...
In this paper, a balanced CPW-fed circularly polarized (CP) antenna is proposed. The antenna consists of two L-shaped monopole radiating elements which are deployed perpendicular to each other to excite orthogonal radiation fields. A 90° delay line section is embedded in one of the differential feedlines to provide 90° phase difference between signals fed to the two input ports. The combination of...
This paper gives a detailed analysis about the causes of the voltage distortion caused by dead time in dual active bridge (DAB) DC-DC converter. The zero-crossing point of the equivalent leakage inductor's current is the definitive factor for various voltage distortion phenomena, which is determined by dead time and phase-shift ratios. Based on the switching characterization of DAB in dual-phase-shift...
In this paper, a kind of interference on chirp pluses in spaceborne SAR and the corresponding suppression method are introduced. This interference is a kind of multi-component linear frequency modulated (LFM) signal which is difficult to be suppression by classical elimination methods. According to the generation mechanism of interference, the mathematical model is established firstly. Moreover, the...
As one widely applied swarm intelligent algorithm, particle swarm optimization (PSO) algorithm has obtained the attention of various scholars with its advantages of easy implementation, high precision and fast convergence. Firstly, aiming to solve the problems that PSO has low searching speed and PSO is easy to fall into local optimal solution especially when dealing with high-dimension model, this...
Aiming at earthquake prediction field, this paper puts forward a multi-expert multi-attribute uncertainty management algorithm based on DS evidence theory. Seismic signal has so much uncertainty that traditional mathematical statistics method cannot solve. Considering DS theory is an excellent uncertainty reasoning method, we extract three instantaneous attributes of plural seismic signal as prediction...
A new method of current balance compensation based on SVG and V/v transformer is proposed to solve the problem of three-phase side current asymmetry caused by traction power supply system of electrified railway. The conditions for elimination of negative sequence current are analyzed. In this compensation system, a total of three single-phase voltage source inverters of SVG are respectively connected...
Rain deteriorates outdoor vision and causes challenge for most vision based intelligent systems. In this paper we propose a method to efficiently remove the rain present in light field data. Firstly, the sub-view image sequence is globally aligned to the central view. Robust Principle Component Analysis (RPCA) are then applied to decompose the sequence into two parts, i.e., the low-rank data, and...
This work develops a new iterative algorithm, which is called stochastic truncated amplitude flow (STAF), to recover an unknown signal × ∊ Rn from m "phaseless" quadratic equations of the form ψ1=|aτi x|, 1 ≤ i ≤ m. This problem is also known as phase retrieval, which is NP-hard in general. Building on an amplitude-based nonconvex least-squares formulation, STAF proceeds in two stages: s1)...
In view of the traditional correlation integral optimization method, when the system disturbances are correlative with the decision variables, objective function does not converge to the optimal value in the process of iterative optimization. In this work, an improved method of correlation integral optimization is proposed. Based on the steady data driven model, an adaptive disturbance estimator is...
In this paper, a self-learning approach is proposed towards solving scene-specific pedestrian detection problem without any human annotation involved. The self-learning approach is deployed as progressive steps of object discovery, object enforcement, and label propagation. In the learning procedure, object locations in each frame are treated as latent variables that are solved with a progressive...
In this paper, we establish a baseline for object symmetry detection in complex backgrounds by presenting a new benchmark and an end-to-end deep learning approach, opening up a promising direction for symmetry detection in the wild. The new benchmark, named Sym-PASCAL, spans challenges including object diversity, multi-objects, part-invisibility, and various complex backgrounds that are far beyond...
Electromagnetic (EM) scattering by chiral objects is formulated by volume integral equations (VIEs). The chiral media belong to bi-anisotropic materials and have a strong directional difference for unknown functions. The VIEs are usually solved by the method of moments (MoM) with the Schaubert-Wilton-Glisson (SWG) basis function which requires conforming meshes and only considers the inhomogeneity...
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