I. H. Baciu

Modeling Transfer Function for Buck Power Converter

Switching regulators offer two main advantages compared to the linear regulators. First, switching efficiency is much better than linear. Second, because less energy is lost in the transfer, smaller components and less thermal management are required. A switching power supply has to assure the stability between input and output voltage, the stability between load and output voltage, and a good transient response between different disturbances signals. The paper will outline a mathematical method for modeling the transfer function for switching power supplies. That model will be implemented in Simulink and after that, the result will compared with PSpice. This model can be used to design a best control for power converters.

Advanced CAD Methods for Designing High Quality Power Systems

Nowaday electronic systems require more and more efficient energy solutions taking into consideration the CEE rules on this matter. Even more, the cost effective limitations applied to any electronic design will force electronic producers to solve CEE compliance issues as early as possible, in the stage of designing the product .For this purpose, modeling and simulation of the power generation/consumption behavior will help designers in finding proper solutions for their products. The paper will outline a method for modeling and simulation of power devices in order to achieve the quality required for energy flow into electronic devices.

Advanced methods of generating signals to command switching converters

This paper presents the implementation of a signal generator using a 12-bit DAC. The applications were developed in LabView software and are used for transposing in a FPGA code sequences for communicating with the DAC and for analytical implementation of the generated signal. For practical implementation of the signal generator the following hardware components were used: Spartan 3E development board and the peripheral module PmodDA2. The waveform of the generated signal is set based on an analytical expression implemented in LabView (with the PC host) using MathScript function. Signal generation is possible by using PmodDA2 module. Infinite discrete sequences form the analog signal, controlled by the software application developed in Labview (the host is Spartan 3E development board).

Resonance in power converters circuits

The story about resonant circuits its important for understanding the operation behavior of resonant power converter. The aim of this study is to made the students to understand how can they apply mathematics relations in study of this phenomenon and to know how we can apply it in power supply circuits. For the resonance we must have at least two reactive components. One of these components is a capacitor and another is an inductor. The difference between them is the phase angle between current and voltage. The most important thing is to put in evidence, in situation of resonance, the minimum impedance of equivalent circuit, the angle phase zero between voltage and current and the current and voltage sinusoidal shape. If we apply this circuit in a power converter supply and if we make an analysis about this the conclusion which we obtain is about the frequency of stimulation signal. To eliminate the multiple commutations we must have an equal or bigger commutation frequency like resonant frequency. For this paper I realize to a simple application in Matlab to compute the frequency of equivalent circuit and to simulate Buck converter with ZVS commutation and ZCS commutation.

Advanced simulation of load variation in induction heating systems

All induction heating applied systems are developed using electromagnetic induction. Electromagnetic induction refers to the phenomenon by which electric current is generated in a closed circuit by the fluctuation of current in another circuit placed next to it. The basic principle of induction heating is that AC current flowing through a circuit affects the magnetic movement of a secondary circuit located near it. The fluctuation of current inside the primary circuit provided the answer as to how the mysterious current is generated in the neighboring secondary circuit.

Comparison between different method to obtain the solution for differential equations of half bridge inverter

The paper presents a study about half bridge invertors and a MATLAB tool for simulation this type of invertors. This tool describes a comparison between two modes of solution for differential equation. The period of commutation is divided in four intervals. Interval one, when we want to open Q1 transistor, interval two and four when all component are blocked, and interval three when we want to open Q2 transistor. These entire intervals are modulated with mathematical equations which are resolved with two methods.

Wireless diagnosis and monitoring system of sensor network from civil structures

This paper is focused on the development of a wireless device used in diagnosis and monitoring of sensors networks from civil structures like hydro-energetic buildings. Those constructions are monitored with sensors and measurement systems spread over the entire constructions body. The measurement systems are connected through a RS485 network. The entire structure forms a data acquisition system that is usually controlled by a software application that runs on a computer. A daily management activity in hydro-energetic buildings consists in an automatic and a manual data collection. At the physical layer, in real life, the measurement devices and RS485 networks can be affected by a set of malfunctions that are dangerous signal integrity for the safety of a human operator. For that reason a manual measurement device based on wireless technology is useful. The issues of signals integrity of RS485 lines are detected with an electronic device that is connected to the lines. In additional, using communication protocol the data from each sensor can be collected. The panel interface of the human operator is a software application that runs on a smart mobile device that uses Bluetooth communication [2]. In the last years the mobile software applications has been greatly increased in industry [1]. By using a software application and a wireless mobile device a diagnosis and monitoring system is developed which is more safety and has a vast development space [3].

Analysing of half-bridge inverter using the Simulink platform

Evolution technologies and increasing consumption constrain us to think of reducing resource consumption. This cannot be achieved except through improvements of existing systems and the invention of new systems. One of these systems is also the induction heating. This system has revolutionized heating systems. If until now was using a simple electrical resistance heating, the new systems use induced current effect intro electric conductive surface. Using these systems has shown that the efficiency of the new systems is approximately 30% higher. This paper presents a theoretical study of an induction heating system whose order is made through an half bridge inverter circuit.

Mathematical model for a quasi-resonant converter

The paper presents a mathematical model for a quasi-resonant converter. This type of converter was analyzed for an induction heating system. The system can have a series or a parallel resonant circuit as a load. In this paper we discussed only series resonant circuit load case.

Tool for design and simulation of Flyback converters

In this paper is presented a mathematical method to design of switching mode power supply with galvanic separation. Also, the intent of this paper is to present a tool for designing of Flyback converter. Using a combination between differential mathematical equation and linear equations implemented in Matlab, a tool for simulation and design of this type of converter was implemented. This tool allows the introduction of minimal number of input data in order to design the converter and returns all the circuit parameters and the characteristic waveforms of the Flyback converter. This tool for designing and simulating of Flyback converter can have a wide range of users, from switching mode power supply design engineers, in order to reduce the time necessary for design this type of converters, to students that learn these kinds of dc-dc power supply. In order to validate the results obtained with the mathematical model implemented in this Matlab tool, a Spice model simulation was also implemented.