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This research study involved the analog CMOS design of an ultra-low power current reference applicable on wireless devices, especially on passive RFID tags. Passive RFID are battery-less circuit that needs to convert incoming RF power into a DC voltage using rectifier circuit. However, the tag can be read only at very short distances, typically a few feet at most. This greatly limits the device for...
This work proposes a Fast Response One Cycle Control (OCC) strategy for Active Power Filters (FOCC-APF). Moreover, a comprehensive study of the OCC technique, exploiting their features and inherent drawbacks to provide a better understanding of this technique is presented. Finally, simulation results of the active power filter with the conventional and proposed strategies are shown to evaluate APF...
As in most of the renewable energy sources it is not possible to generate high voltage directly, the study of high gain dc-dc converters is an emerging area of research. This paper presents a high step-up dc-dc converter based on current-fed Cockcroft-Walton multiplier. This converter not only steps up the voltage gain but also eliminates the use of high frequency transformer which adds to cost and...
Switch mode power supplies generated a wide range of conductive and inductive interference. Moreover, the spectrum dominated by discrete components with a switching frequency of a power transistor and its harmonics. To ensure the electromagnetic compatibility of devices necessary to reduce the amplitude of these spectral components. In this paper the questions of usage of spread spectrum technology...
Based on the analysis of the turbine generator system, steam turbine and its speed governor system, synchronous generator and its excitation controller and load model of turbine generator system are modeled mathematically. Then, the model of turbine generator system is simulated in Matlab/Simulink, the model of turbine generator system can conclude characteristics curves that are similar with actual...
Wind technology is one of the fastest developing renewable technologies. Squirrel cage induction generator (SCIG) with back to back fully rated converter used for wind energy conversion systems (WECS) is a meritorious option among its class. SCIG's offer advantages of being robust, suitable for any harsh environment, cheaply available and unsophisticated than the other types available. To enable increased...
There is now general acceptance that the burning of fossil fuels is having a significant influence on the global climate. In this scenario renewable energies will have to contribute in energy diversity and security of supply. That the world's ever knows a similar rising need of energy. Wind energy is a promising technology and becomes more and more interesting player on the market of energy production...
In this paper, a novel architecture for charging mode controller of Li-Ion battery charger is proposed. It is design to generate stable control signals even when noise level reaches several tens of millivolts. The trickle current is as low as 200mA enabling longer life cycle for Li-Ion battery. The large current reaches 1A without any impact on trickle current offering a faster charging time for Li-Ion...
Most utilities use a standard small generator interconnection procedure (SGIP) process that includes a screen for placing potential PV interconnection requests on a fast track that do not require more detailed study. One common screening threshold is the 15% of peak load screen that fast tracks PV below a certain size. This paper performs a technical evaluation of the screen compared to a large number...
Increasing photovoltaic (PV) penetration is a major driver for developing new methods to integrate renewable generation into distribution systems. For planning of low voltage distribution networks future share of penetrations have to be modeled in an appropriate way, to simulate and analyze the impact of PV generation. Different approaches to model high penetration scenarios - in particular defining...
This paper shows that the flux-decay model of a synchronous generator exhibits the property of differential flatness. Differential flatness will be utilized for planning the generator's trajectory as there is a one-to-one correspondence between output curves and trajectories for states and inputs. Flat outputs of the generator are taken to be the generator's complex current injected into the power...
This paper focuses on black-start of power system with turbine based combined cooling, heating and power (CCHP) systems as start units. Firstly, the relation among inrush current, the capacity of CCHP systems and transformers are researched and summarized by building models and running simulations in PSCAD. Then three typical black-start cases are designed based on the distribution network, and simulation...
This paper presents a clock generator featuring a feedback temperature and voltage compensation circuit and low dropout regulator circuit on-chip capable of constraining frequency variation to 3.49 %. The inclusion of an OPA, MOS transistors and resistors eliminates the need of large BJT devices to reduce the area penalty and achieve low power consumption. Particularly, a negative feedback temperature...
DC distribution systems are emerging in ship applications in order to facilitate fuel saving and low emission. As opposed to the conventional shipboard ac power systems, in a ship dc power system, the generators can rotate independently. This makes the voltage regulation and power sharing to be implemented differently. This paper presents dc voltage control in a shipboard dc power system, while the...
This paper presents a micro-grid simulator tool useful for implementing and testing multi-agent controllers (SGridSim). As a common engineering practice it is important to have a tool that simplifies the modeling of the salient features of a desired system. In electric micro-grids, these salient features are the voltage and power distributions within the micro-grid. Current simplified electric power...
This article presents a modular approach to generate the interleaved carriers of a parallel converters. Compared with previous solutions requiring accurate analog computations, a straightforward implementation of the generator is proposed here. By using only comparators and logical gates dedicated to the tuning of the carrier phase, a correct interleaving of the carriers is obtained in steady-state...
Several methods that can be used to verify effectiveness of startup circuits in eliminating known stable Trojan operating states will be discussed. It will be shown that some widely used approaches do not guarantee Trojan states have been removed. Some of the methods introduced appear to be more practical to work with than others. These methods can also be used to identify the presence of unknown...
Three phase power, especially for pumping applications, is highly desired in many rural applications. For economic reasons, many of these installations are supplied from single phase medium voltage networks. This paper shows that a well-balanced three phase supply, suitable for induction machine supply, can be produced with a Scott transformer connection of a single phase inverter and the existing...
The field trials in the two MV grids - ‘Großes Walsertal’ and ‘Lungau’ give new insights to the voltage control algorithms developed prior over the last couple of years. These experiences include: Advancement of the voltage control with the on load tap changer and the distributed generators’ reactive power - ‘range’ and ‘level’ controller respectively - towards better utilization of the voltage band...
This paper presents a new structure of variable gain amplifier (VGA) in which a modified Gilbert Cell is firstly proposed to implement a low power wide dynamic range VGA. The proposed VGA can provide 50-dB dynamic range within a linear error of 1-dB. Furthermore, the proposed circuit consumes less than 0.5-mA current and occupies about only 0.12-mm2 chip area, both of which are relatively low in terms...
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