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This paper presents the study of dynamic modeling and control of a converter of multiple inputs (MIC) with MPPT. There are two independent inputs, wind and photovoltaic sources (PV), connected to a DC bus, and a single converter (MIC) as a means of reducing system costs. In order to extract maximum energy from the PV system for a given solar irradiance and temperature, an approach of adjusting the...
Delayed hot water in domestic water heating systems is a worldwide problem with an estimated loss of 15,000 litres of treated water annually per average household. Commercially available systems to overcome this issue cost several thousand dollars and they occupy space and modifications to plumbing. Supercapacitor (SC) assisted temperature modification apparatus (SCATMA), a patent-pending technique...
When an ideal voltage source is used to replenish an electro-chemical battery with an open circuit voltage of V and a charge of Q coulombs, it stores an energy of QV in the battery, if the charging loop is ideal with no losses. However, if the electro-chemical battery is to be replaced by a capacitor, the energy stored will be ½QV and the loop resistance will dissipate ½QV of energy creating an overall...
Although supercapacitors are more cyclable than batteries, as they don't imply faradic reaction for energy storage, they are subject to ageing. The main ageing causes are temperature and voltage. This article investigates the effect of a supplementary ageing cause which is high frequency ripple current. Indeed, ripple current is a problem happening for DC networks using power electronics converters...
This paper presents a compression algorithm for power quality (PQ) signals, which does not separate the signal into stationary and transient components. The proposed algorithm is composed of a number of different compression techniques which are combined to improve both compression ratio and total computing time. This method is based on a sequence of three phases. The first phase transforms the signal...
The field of Machine Vision is still dominated by classical imaging systems consisting of a camera attached to a PC. Especially very fast processes with high requirements on minimal latency or maximal refresh rate are increasingly starting to stretch such systems to their limits. Image sensors with integrated feature extraction - so-called “Vision Chips” - already allow reducing the amount of data...
In this paper a predictive current control strategy with a fixed switching frequency for a voltage source inverter is proposed, with the aim of obtaining a modulated waveform at the output of the converter with a natural reduction of the common mode voltage. The feasibility of this strategy is evaluated using simulation results to demonstrate the advantages of predictive control, such as fast dynamic...
Machine vision methods to provide spatial coordinates measurement has developed in a wide range of technologies for multiples fields of applications such as robot navigation, medical scanning, and structural monitoring. Each technology with specified properties that could be categorized as advantage and disadvantage according its utility to the application purpose. This paper presents the photodiode...
Voltage waveform improvement has been the object of several investigations for many years and a manifold of different solutions have been proposed to reduce the harmonic content in Voltage Source Inverters (VSI) power application. In many cases this improvements have been obtained by modifying the reference voltage modulating signal. The recent introduction of cardinal B-spline functions, used as...
The understanding of the interrelationships among the photometrical, electrical and thermal (photo-electro-thermal) parameters is extremely important to design lighting systems based on light-emitting diodes (LEDs). This paper proposes an improvement in the estimation of the luminous flux previously proposed in A General Photo-Electro-Thermal Theory (PET Theory), using information taken only from...
This paper presents the analysis, design and simulation of a digital control strategy for an electronic ballast to supply a 100 W high frequency Electrodeless Fluorescent Lamp (EFL). The electronic topology consists of a single-stage SEPIC power-factor converter associated with a half-bridge asymmetric LCC resonant inverter. In this configuration, the dimming capability based on a low-frequency burst-mode...
The use of series-resonant converters (SRC) in light emitting diodes (LEDs) drivers has increased due to its simplicity and high efficiency. Furthermore, the use of SRC provides a reduction of the low frequency (LF) ripple in the LEDs' current, originated by the voltage ripple in the output of the power factor correction (PFC) stage (bus voltage ripple). Thus, the attenuation of the ripple transmission...
This paper presents a three-phase switched capacitor converter to drive power light-emitting diodes (LEDs). The proposed converter does not utilize electrolytic capacitors, providing a high useful lifetime. In addition, the converter does not have diode bridge input rectifier, which can increase the converter efficiency. Moreover, it can stabilize the output current in open loop control, without needing...
This paper presents the analysis and design of a self-oscillating electronic ballast with universal input voltage range (100–240 VRMS) and power factor correction to supply a T8 32 W fluorescent lamp. The power factor correction stage consists of a DC-DC converter operating in discontinuous conduction mode. The lamp is supplied by a half-bridge resonant inverter and a self-oscillating command circuit...
This paper presents a new theoretical equivalent model (TEM) for Organic Light-Emitting Diodes (OLEDs). This TEM is useful to simulate and analyze OLED dedicated drivers, considering dynamic and steady-state operation conditions. A simple characterization procedure to OLED parameter identification is presented. Based on this procedure an OLED sample is used to validate the proposed modeling.
Distribution STATic synchronous COMpensators (DSTATCOMs) have been proved an effective approach to compensate reactive current in distribution network. With positive-sequence component, negative-sequence and zero-sequence component of unbalanced load current detected independently, selective reactive current compensation with individual phase control strategy can be realized. To improve the steady...
In this paper a Predictive Current Control strategy is proposed for constant switching frequency operation and verified with a neutral-point-clamped (NPC) converter for load current regulation and DC-link capacitor voltages balancing. The aim of this control technique is to obtain a modulated waveform at the output of the converter, whilst maintaining all the desired characteristics of FCS-MPC. The...
Every power converter needs a precise synchronization method to be able to connect to the utility grid. The synchronization impacts directly on the performance of the converter. Synchronization algorithms are often based on the well known Synchronous Reference Frame Phase Locked Loop (SRF-PLL). These are usually implemented in software on Digital signal Processors (DSP) or Microcontrollers and the...
This paper considers the control of a 7-leg back-to-back Voltage Source Inverter (VSI) arrangement feeding a 4-wire load from a 3-phase Permanent Magnet Synchronous Generator (PMSG) operating at variable speed. The 7-leg converter is regulated using Resonant Controllers (RCs) at the load side and self-tuning resonant controllers at the generator side. The control system is augmented by a feed-forward...
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