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Noise analysis of a widely used switched capacitor unity gain sampler is presented, which in detail shows that the circuit structure can not only get rid of the offset voltage induced by the OTA involved, but also has the ability of suppressing 1/f noise with operation timing of the sampling capacitor, functioning as correlated double sampling in fact, however paying the price of increasing thermal...
This paper presents a feasibility study on the prototyping of a hybrid EPAC (Electric Pedal Assisted Cycle) through an FC-B-UC (Fuel Cell — Battery — Ultra-Capacitors) power system. Aim of this work is the characterization of a PEMFC (Proton Exchange Membrane Fuel Cell) in order to confirm its theoretical performances and to verify the possibility of its installation on an e-bike.
Multilevel inverters are high voltage, high power devices with wide electrical applications due to their lower output harmonic component and device stress management capabilities. Manifold control strategies have been proposed and implemented for MLIs and fundamental frequency switching strategies are especially suited due to their ability to provide for higher efficiency. This paper proposes a hybrid...
During preliminary design sketch phases, the power electronics designer has to propose optimal solutions complying with system level requirements, which are continuously evolving since the global system is not finalized. It is particularly complicated in the cases of wide operating ranges where the optimal design for the most constrained operating point does not necessarily provides the optimal design...
In this paper we review some of the fundamental limits of dc-dc power converters described in 1966 and 1969 and generate an averaged power model that is useful to perform high-level comparison of power converters and architectures. The model is extended to 3 port power converters, which is used to calculate the minimum possible internal power to be processed by the components of the power stage of...
An electromagnetic interference (EMI) filter design method for electric vehicle (EV) application is proposed in this paper. By transforming the design problem to an optimization problem, the filter volume, system disturbance level, inverter touch current and filter leakage current are taken into account simultaneously. A topology and order evolution approach is merged into the optimization algorithm...
A model predictive control system for delta-connected modular multilevel converter is proposed in this paper. The control system is based on offline computed optimal pulse patterns, which are modified online using model predictive control. Optimized pulse patterns facilitate the shaping of the grid current spectrum at low switching frequencies. Unlike conventional control methods with optimal pulse...
A hybrid modulation approach is proposed in this work, which allows to modulate the switches of the five level neutral point clamped inverter (5LANPC) with different switching frequencies. Some of the switches are controlled with a low switching frequency using six-step modulation and Optimized Pulse Patterns (OPPs), whereas the rest are modulated with a high switching frequency using Carrier-Based...
The multiobjective allocation optimization of single tuned passive power filters for decreasing the power losses and harmonic mitigation in distribution networks is presented in the paper. The Pareto definition of the multiobjective problems is used in the paper. The two objectives problem consists of the two technical objective functions, the real power losses and the total harmonic distortion, is...
This paper presents a complete design procedure for a motor drive aiming at maximizing nominal power within loss (30 W) and form factor (60 inch3) constraints. Particularly, this motor drive system has EMI requirement on both input and output sides and it should be free convection cooled. Loss-size Pareto fronts of multiple three-phase topologies including two-level voltage source converter (VSC),...
Voltage quality is an essential requirement in the operation of electricity distribution systems. At consumer busbars, the deviation from the nominal voltage has specific ranges, prescribed in technical regulations. A widely chosen voltage correction approach is to use reactive power compensation. Capacitor banks are used for this purpose in highly loaded networks, but their placement and sizing require...
The optimal capacitor allocation in electricity distribution networks (EDN) plays a meaningful role in voltage profile improvement, power factor amelioration and also power losses minimization. This work presents two comprehensive optimization algorithms based on metaheuristics as a comparison to solve the capacitor allocation problem in modern distribution networks. Thus, the problem of optimal capacitor...
With reliability and flexibility criteria surging, multi-level converters become of growing interest for high-power medium-voltage renewable energy applications. Specific objectives are met with specialized intelligent controls. The goal of this paper is to present a universal intelligent controller able to manage all degrees of freedom of multi-level power converters and any paradigm. To do so, a...
Researches on electromagnetic repulsion mechanisms are drawing more and more attention globally. The objective of this paper is to develop an electromagnetic repulsion mechanism for a 40.5 kV vacuum circuit breaker and then to make an optimization. Design of experiments (DOE) method are used to screen the prominent factors. Result shows that three impact factors are the prominent factors, which include...
PFC converters are widely used in industrial drive systems. The modulation scheme and the topology of the converter have a considerable impact not only on the switching losses, but also on the volume of the passive components, i.e. the EMI filter (CM and DM) and the dC link capacitors. In order to evaluate this impact, different modulation schemes for 2L and 3L topologies are analysed in this paper...
Thermal energy harvesting systems use boost converters for high-efficiency low voltage operation, but lack the ability for low voltage startup without off-chip transformers. We present a cold start system that uses integrated magnetics instead of external transformers in a Meissner Oscillator to start up from ultra low voltages, with a switched capacitor DC-DC circuit for additional voltage gain....
In this paper, we consider an optimization problem solving for model predictive control (MPC) of a modular multilevel converter (MMC). An MMC consists of a large number of submodules. The objective of the MPC is to determine the best switching sequences for the submodules in the MMC to track the phase current references for T time horizons. The MPC is formulated as a nonlinear mixed-integer programming...
With the R&D of high voltage direct current (HVDC) transmission, HVDC circuit breaker as the protection equipment has been widely applied in the power system. In this paper, the HVDC vacuum circuit breaker (VCB) based on artificial zero mode has been analyzed, and the genetic algorithm (GA) has been used to optimize the parameters of DC VCB. Moreover, an optimization design method of converting...
Modular Multilevel Converters (MMC) are being widely considered for shipboard applications. Designing such converters through multi-objective optimization is of interest, because such an approach allows the trade-off between competing objectives (for example, mass and loss) to be explicitly and quantitatively identified. However, doing so can require 104–106 time domain simulations in order to rigorously...
The increasing penetration of electric vehicles (EVs) will bring great challenges to the secure and economic operation of distribution networks. On the other hand, coordinated charging of EVs can alleviate the adverse impacts of charging loads and even increase the efficiency of distribution network operation. This paper aims at optimally scheduling the daily charging of EVs and the daily on/off switching...
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