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The purpose of this study is to find a control method for three-phase four-wire shunt active power filters, which uses a load-equivalent conductance for obtaining a reference signal for compensating non-active current.

Changes of energy stored in an active filter’s reactance elements are monitored to find the active component of the load current. It is then used as a current reference to be realised as a supply source current. Computer simulation methods were used to verify the presented control method.

To calculate the reference signal for the active filter action, it is enough to measure the active filter’s DC-side capacitors’ voltages. It has been proved that P regulators are sufficient to realise compensating current and to stabilise active filter capacitors’ voltages. The supply source-neutral conductor current can be zeroed even for nonlinear and unbalanced load-generating DC-component in its neutral conductor. In addition, the active filter can buffer load-active power changes and act simultaneously as a local energy accumulator.

This paper provides an alternative approach to address the problem of the three-phase four-wire shunt active power filter control methods.

Norbert Wiener’s cybernetic paradigm represents one of the seminal ideas of the twentieth century. Nevertheless, its full potential has yet to be realized. For instance, cybernetics is relatively little used as an analytical tool in the social sciences. One reason, it is argued here, is that Wiener’s framework lacks a crucial element – a functional definition of information. Although so‐called Shannon information has made many valuable contributions and has many important uses, it is blind to the functional properties of information. Here a radically different approach to information theory is described. After briefly critiquing the literature in information theory, a new kind of cybernetic information will be proposed called “control information.” Control information is not a “thing” but an attribute of the relationships between things. It is defined as: the capacity (know‐how) to control the acquisition, disposition and utilization of matter/energy in purposive (cybernetic) processes. This concept is briefly elucidated, and a formalization proposed in terms of a common unit of measurement, namely the quantity of “available energy” that can be controlled by a given unit of information in a given context. However, other metrics are also feasible, from money to allocations of human labor. Some illustrations are briefly provided and some of the implications are discussed.

The purpose of this study is to compare two unsteady actuators: an oscillator and a sweeping jet. Both actuators can produce an oscillating jet of different amplitudes and frequencies without any moving parts, making them an attractive actuator concept. The Coanda effect phenomenon can explain the operating principles of these two unsteady actuators.

A numerical study was conducted to compare the amplitudes and frequencies of fluidic and sweeping jet (SJ) oscillators to obtain an efficient actuator to control separated flows at high Reynolds numbers. For this goal, two-dimensional unsteady Reynolds-averaged Navier-Stokes simulations were carried out using computational fluid dynamics (CFD) fluent code to evaluate the actuator performances. The discrete fast Fourier transform method determined the oscillation frequencies.

The oscillation frequencies gradually increase as the inlet pressure increases. The characteristics and dimensions of the vortices produced in the mixing chamber and feedback loops vary overtime when the injected fluid is swept sideways. The frequencies supplied by the SJ are stronger than those obtained by the fluidic oscillator, which may contribute to improving the aerodynamic performance at a lower power supply cost.

The existence of the splitter in the fluidic oscillator led to the production of separate pulses, which would be useful in various industrial applications, including active control of combustion and mixing processes while other applications such as flow separation control require SJs. With the latter actuator higher and interesting frequencies can be obtained, leading to efficient flow control.

Nowadays, distributed generation and microgrids (MGs) are becoming an important research line because of their peculiar characteristics. MGs are composed of small power sources which can be renewable, placed near customer sites. Moreover, they have the inherent property of islanding: the disconnection of either the MG from the main grid or a part of a MG from the rest of the MG. The purpose of this paper is to study two different control strategies allowing grid connected and islanding operation of the MG.

In this paper, the behaviour of a particular MG during grid connected and islanding operation is investigated. The studied MG is based on different energy sources: a wind turbine, a photovoltaic array, a backup diesel generator and a storage system. The renewable sources and the storage system are connected on a DC bus which is interconnected with a main grid through a voltage source inverter (VSI). The attention focuses on the control technique of the VSI during grid connected and islanding operation of the MG. The behaviour of the AC signals on the point of common coupling between the MG and the main grid as well as the DC signals on the DC bus on which are connected renewable energy sources of the MG has been investigated by simulation using a MATLAB/Simulink model.

For the investigated MG, the simulation results show that using a single master VSI and classical control strategies, it is possible to have a good power quality on the MG during grid connection and islanding operation.

This paper investigates the behaviour of a particular MG in order to analyse two different control strategies allowing grid connected and islanding operation.

Renewable energy sources such as solar photovoltaic (PV) and wind are ubiquitous because of their lower environmental impact. Output from solar PV and wind turbines is unstable; hence, this article aims to propose an effective controller to extract maximum available power.

By focusing on the varying nature of solar irradiance and wind speed, the paper presents the maximum power point tracking (MPPT) technique for renewable energy sources, and power regulation is made by the novel inverter design. Moreover, a DC–DC boost converter is adopted with solar PV, and a doubly fed induction generator is connected with the wind turbine. The proposed MPPT technique is used with the help of a rain optimization algorithm (ROA) based on bi-directional long short-term memory (Bi-LSTM) (ROA_Bi-LSTM). In addition, the sinusoidal pulse width modulation inverter is used for DC–AC power conversion.

The proposed MPPT technique has jointly tracked the maximum power from solar PV and wind under varying climatic conditions. The power flow to the transmission line is stabilized to protect the load devices from unregulated frequency and voltage deviations. The power to the smart grid is regulated by three-level sinusoidal pulse width modulation inverter.

The methodology and concept of the paper are taken by the author on their own. They have not taken a duplicate copy of any other research article.

The purpose of this paper is to carry out a detailed analysis of two port converter fed by Solar and wind sources during different operational modes by small signal modelling. The converter is fully characterized and simulated using Matlab/Simulink. The voltage and current waveforms along with their corresponding expressions describing the converter operation are presented in detail. Then the DC-averaged equivalent topology is derived using circuit averaging technique. A complete derivation of the power stage transfer functions relevant to the capacitor voltage loop, such as capacitor voltage to solar voltage and inductor current to wind input voltage is obtained.

Stability analysis is used to analyze the small deviations around the steady-state operating point which helps in modeling the closed loop converter parameters. This paper presents the analysis, modeling and control of two port Cuk-buck converter topology.

Based on the results, a control strategy is designed to manage the energy flow within the system. A lab-level prototype for Cuk-buck converter with PWM controller is implemented and tested under various input conditions to study the performance of the converter during seasonal changes. The simulation and experimental results showed that effective operation and control strategy of the hybrid power supply system managed to be achieved alongside its feasible outputs.

This analysis can be extended to all power electronic converters and will be useful for the design of controllers.

An appropriate control design plays a key role in enhancing the overall performance of the system. Hence, this paper is intended to present in detail the small signal modeling of the Cuk-buck converter along with the control design for all the switching modes.

Though this type of converter topology has been discussed widely in literature, very scarce literature is available related to modeling and control design of the converter. A state-space averaging model of the converter followed by a type-II compensator design is described, and prototype design and experimental results are also presented.

In residential buildings, personal choices influence electricity and water consumption. Prior studies indicate that information feedback can stimulate resource conservation. College dormitories provide an excellent venue for controlled study of the effects of feedback. The goal of this study is to assess how different resolutions of socio‐technical feedback, combined with incentives, encourage students to conserve resources.

An automated data monitoring system was developed that provided dormitory residents with real‐time web‐based feedback on energy and water use in two “high resolution” dormitories. In contrast, utility meters were manually read for 20 “low‐resolution” dormitories, and data were provided to residents once per week. For both groups, resource use was monitored during a baseline period and during a two week “dorm energy competition” during which feedback, education and conservation incentives were provided.

Overall, the introduction of feedback, education and incentives resulted in a 32 percent reduction in electricity use (amounting to savings of 68,300 kWh, $5,107 and 148,000 lbs of CO₋₂) but only a 3 percent reduction in water use. Dormitories that received high resolution feedback were more effective at conservation, reducing their electricity consumption by 55 percent compared to 31 percent for low resolution dormitories. In a post‐competition survey, students reported that they would continue conservation practices developed during the competition and that they would view web‐based real‐time data even in the absence of competition.

The results of this research provide evidence that real‐time resource feedback systems, when combined with education and an incentive, interest, motivate and empower college students to reduce resource use in dormitories.

This is the first study to report on the effects of providing college students with real‐time feedback on resource use. The authors of this study are currently engaged in further research to determine: whether reductions in consumption can be sustained over time with and without incentives; the degree to which feedback affect attitude; and the degree to which findings are transferable to apartments and other residential settings.

Due to technological improvement and development of the vehicle-to-home (V2H) concept, electric vehicle (EV) can be considered as an active component of net-zero energy buildings (NZEBs). However, to achieve more dependable results, proper energy analysis is needed to take into consideration the stochastic behavior of renewable energy, energy consumption in the building and vehicle use pattern. This study aims to stochastically model a building integrating photovoltaic panels as a microgeneration technology and EVs to meet NZEB requirements.

First, a multiobjective nondominated sorting genetic algorithm (NSGA-II) was developed to optimize the building energy performance considering panels installed on the façade. Next, a dynamic solution is implemented in MATLAB to stochastically model electricity generation using solar panels as well as building and EV energy consumption. Besides, the Monte Carlo simulation method is used for quantifying the uncertainty of NZEB performance. To investigate the impact of weather on both energy consumption and generation, the model is tested in five different climatic zones in Iran.

The results show that the stochastic simulation provides building designers with a variety of convenient options to select the best design based on level of confidence and desired budget. Furthermore, economic evaluation signifies that investing in all studied cities is profitable.

Considering the uncertainty in building energy demand and PV power generation as well as EV mobility and the charging–discharging power profile for evaluating building energy performance is the main contribution of this study.

The purpose of this paper was to present a soft landing control strategy for a biped robot to avoid and absorb the impulsive reaction forces (which weakens walking stability) caused by the landing impact between the swing foot and the ground.

First, a suitable trajectory of the swing foot is preplanned to avoid the impulsive reaction forces in the walking direction. Second, the impulsive reaction forces of the landing impact are suppressed by the on-line trajectory modification based on the extended time-domain passivity control with admittance causality that has the reaction forces as inputs and the decomposed swing foot’s positions to trim off the forces as the outputs.

The experiment data and results are described and analyzed, showing that the proposed soft landing control strategy can suppress the impulsive forces and improve walking stability.

The main contribution is that a soft landing control strategy for a biped robot was proposed to deal with the impulsive reaction forces generated by the landing impact, which enhances walking stability.

The purpose of this paper is to analyze the thermal-diffusion and diffusion-thermo effects on magnetohydrodynamics (MHD) natural convective flow through porous medium in a rotating system with ramped temperature.

Using the non-dimensional variables, the flow governing equations along with corresponding initial and boundary conditions have been transformed into non-dimensional form. These non-dimensional partial differential equations are solved by using finite element method. This method is powerful and stable. It provides excellent convergence and flexibility in providing solutions.

The effects of Soret number, Dufour number, rotation parameter, magnetic parameter, Hall current parameter, permeability parameter, thermal Grashof number, solutal Grashof number, Prandtl number, thermal radiation parameter, heat absorption parameter, Schmidt number, chemical reaction parameter and time on the fluid velocities, temperature and concentration are represented graphically in a significant way and the influence of pertinent flow governing parameters on the skin frictions and Nusselt number are presented in tabular form. On the other hand, a comparison for validation of the numerical code with previously published work is performed, and an excellent agreement is observed for the limited case existing literature.

A very useful source of information for researchers on the subject of MHD flow through porous medium in a rotating system with ramped temperature.

The problem is moderately original, as it contains many effects like thermal-diffusion (Soret) and diffusion-thermo (Dufour) effects and chemical reaction.