Grid impedance affects the stability and control performance of grid-connected power electronic devices, such as inverters used to integrate wind solar energy. Adaptive inverters, guarantee under different grid conditions, requires online measurement performed in real time. Such can be by injecting a current perturbation from inverter into reading voltage responses. To minimize impact on operation, injection must kept small possible while producing enough that reliably measured processed...

Grid impedance and the output of grid-connected inverter are important parameters for operation systems, such as solar, wind, other distributed-generation resource systems. The mismatch between grid interfacing circuit often generates harmonic resonances that lead to reduced power quality even instability. Since impedances usually vary over time a function many parameters, online measurements required stability assessment adaptive control inverters. Several methods have been proposed quick,...

Online measurements of the battery impedance provide valuable information on state-of-charge and state-of-health, which can be utilized for improving safety performance associated system. The electrochemical-impedance spectroscopy (EIS) is widely used measurements, but it not most applicable solution online due to its slowness complexity. These drawbacks improved using broadband signals, such as pseudorandom sequences (PRS), are fast easily implementable. However, nonlinear behavior...

Many modern commercial ships are electric ships, i.e., they utilize integrated propulsion (IEP ), where motors with variable speed drives used for ship propulsion. This provides a number of advantages, such as reduced size and weight, power availability aboard the ship, vibration, more flexibility in generation engine placement by eliminating mechanical connection between engines Most cruise many yachts, even cargo IEP. There is also significant interest IEP military ships.

Grid impedance is an important parameter for the operation and control of grid-connected inverters used integration solar, wind, other distributed generation resources. Since grid usually varies over time with conditions, online measurement required adaptive inverters. Existing methods based on impulse perturbation Fourier analysis require large current or voltage injection that may interfere normal inverter. This paper proposes use maximum-length binary sequence (MLBS) averaging techniques...

Grid impedance has a major effect on the operation of inverter-connected systems, such as renewable energy sources. Stability system depends ratio inverter output and grid at point common coupling. Because varies over time with many parameters, online grid-impedance measurement acquired in real is most preferred method for observing stability. Recent studies have presented methods based multiple-input-multiple-output (MIMO) identification techniques, where stability grid-connected rapidly...

Grid impedance affects the stability and control performance of grid-connected power-electronics devices, such as inverters, used to integrate wind solar energy. Adaptive guarantee under different grid conditions, requires online measurement performed in real time. Wideband frequency-response-measurement techniques based on pseudo-random binary sequence (PRBS) or impulse injection have been often applied for grid-impedance measurements. However, while using PRBS impulse, it is assumed that...

The operation of more electric aircraft is dependent on the embedded power grid. Therefore, on-board power-distribution system must be reliable, having a high level survivability, and promptly respond to any change in aircraft's operation. Recent studies have presented number frequency-response-based tools with which analyze both single- multiconverter systems. methods can efficiently applied for analysis, stability assessment, adaptive control design. Most often, wideband measurement...

The impedance of lithium-ion (Li-ion) batteries contains information about the dynamics and state parameters battery. This can be utilized to improve performance safety battery application. is typically modeled by an equivalent-circuit-model (ECM), which provides dynamic In addition, variations in model used for estimation. A fitting algorithm required parametrize ECM due nonlinearity both ECM. However, conventional algorithms, such as complex-nonlinear-least-squares (CNLS) algorithm, often...

DC distribution systems typically consist of several feedback-controlled switched-mode converters forming a complex power system. Consequently, number issues related to stability arise due interactions among multiple converter subsystems. Recent studies have presented methods such as passivity-based criterion, where the and other dynamic characteristics an interconnected system can be effectively analyzed using bus-impedance measurement. Studies online measurement techniques, bus impedance...

LCL-filter is commonly used to attenuate the switching harmonics of grid-connected converters. LCL -filter creates resonances in converter dynamics which shall be damped for ensuring robust performance converter. Active damping methods can resonant behavior effectively. Accordingly, output impedance affected and grid-interaction sensitivity varies with active design. In order carry out impedance-based stability analysis or assessment harmonic rejection capability, an accurate analytical...

A large share of renewable energy production is connected to a weak grid with significant impedance. The transmission impedance causes unintended flow reactive power grid, coupling the active fed from inverter. losses, strains requirements, and can even compromise system stability. Requirements on support were recently imposed new photovoltaic inverters, which are often implemented proportional factor control or droop for local voltage regulation. present work proposes method real-time...

This paper presents a CMOS MEMS-based thermoelectric energy generator (TEG) device with an efficient heat dissipation path. For present devices, the output performance is greatly limited by high thermal-contact resistance in system. proposed work, silicon substrate etched into two comb-shaped blocks thermally isolated from each other, which form hot and cold sides. Thin-film-based thermal legs are densely located between along winding split line. Low internal achieved symmetrical structure....

DC power distribution systems typically consist of several source converters supplying load through single or multiple dc buses. Such complex are prone to stability issues caused by the interactions among feedback-controlled converters. Additionally, interconnected undergo considerable changes in their operating points. This can cause a system that is well-stabilized at certain point go unstable for another condition. Therefore, stabilization method capable adapting variations conditions...

State parameters such as the state-of-charge (SOC) and state-of-health (SOH) play important role in operation of Li-ion batteries, accurate estimate is prime importance evaluating battery condition guaranteeing safe use. While it difficult to measure SOC SOH directly, internal impedance can be used obtain parameters. Recent studies have shown methods based on pseudo-random binary sequence (PRBS) with which rapidly measured real time. Using this method, charged recharged according excitation...

Switched-mode power converters are extensively used to various electronic loads and processes. The use of low-cost components with high parameter variation together the requirement short time market has set new challenges for designers such as necessity characterize a large number before production ramp-up. It been shown that frequency-domain characterization yields most useful information on quality converter. conventional frequency response analyzers can be measuring responses, but...

Switched-mode converters have become extensively used in powering different consumer products. The increased mass production using low-cost components with high parameter variation has set new challenges to designers. Recent studies shown that frequency-domain characterization yields most useful information about the dynamics and quality of a converter. This been widely recognized fast correlation-based techniques developed enabling use frequency-response measurements both design phases....

Power quality problems caused by grid-connected renewable energy inverters have been reported in recent literature. Excessive harmonics and interharmonics may arise when the inverter starts to interact with grid impedance. Small-signal impedance models proven be useful tools analyze stability margins. However, most often voltage feedforward loop employed is not included impedance-based analysis. To fill this gap, paper presents an model, which includes effect of feedforward, presence large...

The impedance of a Lithium-ion (Li-ion) battery has been shown to be valuable tool in evaluating the characteristics such as state-of-charge (SOC) and state-of-health (SOH). Recent studies have impedance-measurement methods based on broadband pseudo-random sequences (PRS) Fourier techniques. can efficiently applied real-time applications where conventional electrochemical-impedance spectroscopy (EIS) is not well suited measure impedance. techniques PRS are, however, strongly affected by...

Switched-mode converters are often the key to operating various electronic systems in everyday life. This means that reliable operation of is prime importance and functioning must be verified during both design phase production. Recent studies have shown can fully characterized by a set frequency responses efficiently used validate analyze related systems. Several methods been proposed for quickly accurately measuring responses, but surprisingly, use multiple-input multiple-output (MIMO)...