Pulse Control Technique Research Articles

A new high speed charge and high efficiency Li-Ion battery charger interface using pulse control technique

A new Li-Ion battery charger interface (BCI) using pulse control (PC) technique is designed and analyzed in this paper. Thanks to the use of PC technique, the main standards of the Li-Ion battery charger, i.e. fast charge, small surface area and high efficiency, are achieved. The proposed charger achieves full charge in forty-one minutes passing by the constant current (CC) charging mode which also included the start-up and the constant voltage mode (CV) charging mode. It designed, simulated and layouted which occupies a small size area 0.1 mm2 by using Taiwan Semiconductor Manufacturing Company 180 nm complementary metal oxide semi-conductor technology (TSMC 180 nm CMOS) technology in Cadence Virtuoso software. The battery voltage VBAT varies between 2.9 V to 4.35 V and the maximum battery current IBAT is 2.1 A in CC charging mode, according to a maximum input voltage VIN equal 5 V. The maximum charging efficiency reaches 98%.

High‐Fidelity Geometric Quantum Gates with Short Paths on Superconducting Circuits

AbstractGeometric phases are robust against certain types of local noises, and thus provide a promising way toward high‐fidelity quantum gates. However, comparing with the dynamical ones, previous implementations of nonadiabatic geometric quantum gates usually require longer evolution time, due to the needed longer evolution path. Here, a scheme is proposed to realize nonadiabatic geometric quantum gates with short paths based on simple pulse control techniques, instead of deliberated pulse control in previous investigations, which can thus further suppress the influence from the environment induced noises. Specifically, the idea is illustrated on a superconducting quantum circuit, which is one of the most promising platforms for realizing practical quantum computer. As the current scheme shortens the geometric evolution path, ultra‐high gate fidelity can be obtained, especially for the two‐qubit gate case, as verified by the numerical simulation. Therefore, the protocol suggests a promising way toward high‐fidelity and robust quantum computation on a solid‐state quantum system.

Coherent multi-comb pulse control demonstrated in polarization-modulated dual-comb spectroscopy technique

A novel coherent pulse control technique that actively exploits the high controllability of multi-comb systems is proposed. We generalize the frequency relationships between comb sources and utilize the relative carrier envelope phase controllability through the relative offset frequency, Δfceo, of the combs. To show the utility of this concept, we demonstrate polarization-modulated comb generation and its coherent detection. This experiment corresponds to an extended dual-comb spectroscopy, in which effective triple-combs are involved in total. Our successful proof-of-principle experiment exhibits the excellent potential of the multi-comb systems, achieving rapid, precise, and arbitrary coherent control in broad metrological applications.

Protection of Three-Phase VSI Grid-Connected PV System During Transient Conditions Using Fuzzy Logic

This paper presents 100 KW three-phase photovoltaic (PV) systems connected to the grid. The system utilizes a two-stage energy conversion power conditioning unit topology composed of a DC–DC boost converter and three-phase voltage source inverter (VSI). The main commonly problem is the capacitor damage of the PV array system during transient conditions due to high impulse voltage when connected to the grid. The problem of VSI capacitor failure during transient conditions is solved in this paper by using fuzzy logic pulse control technique. The fuzzy logic controller is implemented on the three-phase VSI of the PV system. The $$V_{\mathrm{dc}}$$ applied on the capacitor for the above system is tested during transient conditions using two-level and three-level inverters using MATLAB/Simulink.

Master Equation and Control of an Open Quantum System with Leakage

Given a multilevel system coupled to a bath, we use a Feshbach P, Q partitioning technique to derive an exact trace-nonpreserving master equation for a subspace S_{i} of the system. The resultant equation properly treats the leakage effect from S_{i} into the remainder of the system space. Focusing on a second-order approximation, we show that a one-dimensional master equation is sufficient to study problems of quantum state storage and is a good approximation, or exact, for several analytical models. It allows a natural definition of a leakage function and its control and provides a general approach to study and control decoherence and leakage. Numerical calculations on an harmonic oscillator coupled to a room temperature harmonic bath show that the leakage can be suppressed by the pulse control technique without requiring ideal pulses.

펄스형 Nd:YAG 레이저와 단락이행모드의 직류 GMA 열원을 이용한 하이브리드 용접 공정에 대한 연구

Until now, many researches on laser-arc hybrid welding processes have been conducted mainly for high power CW laser and high direct current arc to weld the thick steel plates for shipbuilding. Recently, however the usage of thin steel plates, which tend to be deformed easily by thermal energy, is been increasing because of demand of light structure such as car body in the automobile industry. Accordingly, heat sources having relatively low heat input such as pulsed laser, dip-transfer DC GMA and pulsed GMA seem to be applied more increasingly and the study about those heat sources is needed more intensively. Any heat source mentioned above can not stand alone without weld defects at a relatively high welding speed for increasing the welding productivity. This is main reason to apply the hybrid welding process which uses pulsed laser and low-heat-input GMA heat sources simultaneously to weld the thin steel plate. In this study, parameters of pulsed laser and dip-transfer DC GMA welding are studied firstly through preliminary experiments, and then analyzed in the viewpoint of their physical phenomena. Before conducting the hybrid welding, a pulse control technique is developed based on the parallel port communication and Visual C++ 6.0. Owing to development of this technique, interactions of laser and arc pulses can be controlled consistently. Using the pulse control technique, the hybrid welding is conducted and then its interactive welding phenomenon is analyzed.

Resonant cancellation of off-resonant effects in a multilevel qubit

Off-resonant effects are a significant source of error in quantum computation. This paper presents a group theoretic proof that off-resonant transitions to the higher levels of a multilevel qubit can be completely prevented in principle. This result can be generalized to prevent unwanted transitions due to qubit-qubit interactions. A simple scheme exploiting dynamic pulse control techniques is presented that can cancel transitions to higher states to arbitrary accuracy.

Modeling and control of an electrorheological device for structural control applications

This paper presents some of the results of an experimental and analytical study of a controllable electrorheological (ER) device configured to induce an adjustable amount of dynamic shear force in response to an applied voltage. Maps of the force-deformation characteristics of the aluminosilicate based ER material are developed over a relatively wide frequency range, and approximating analytical expressions are obtained for the force-deformation-frequency-voltage characteristics of the material. Subsequently, an evaluation is made of the efficiency of using online control of an electrorheological actuator to emulate the operation of an optimally tuned auxiliary mass damper attached to a primary system subjected to arbitrary dynamic environments. It is shown through numerical simulation studies that the proposed parameter control algorithm provides an efficient means for the online control of the primary system under a wide range of excitations. An experimental study is presented in which an ER device is used, in conjunction with a small laboratory building model, as a semiactive element in an online structural control approach using pulse control techniques.