This paper presents the design and analysis of a parallel connected inverter configuration of. The configuration consists of parallel connected three-phase dc/ac inverter. Series resistors added to the inverter output to maintain same... more
This paper presents the design and analysis of a parallel connected inverter configuration of. The configuration consists of parallel connected three-phase dc/ac inverter. Series resistors added to the inverter output to maintain same current in each inverter of the two parallel inverters, and to reduce the circulating current in the parallel inverters to the minimum. High frequency third harmonic injection PWM (THIPWM) employed to reduce the total harmonic distortion and to make maximum use of the voltage source. DSP was used to generate the THIPWM and the control algorithm for the converter. Selected experimental results have been shown to validate the proposed system.
In this paper, a method is proposed to improve the frequency stability and accuracy of the generated wave in DC/AC square wave inverters using a microcontroller-based stabilized oscillator circuit. The proposed technique relies on using... more
In this paper, a method is proposed to improve the frequency stability and accuracy of the generated wave in DC/AC square wave inverters using a microcontroller-based stabilized oscillator circuit. The proposed technique relies on using the 8051 microcontroller as a stable oscillator to generate two anti-phase 50 Hz square waves for the driving power stage of the inverter based on a program stored in its internal ROM. These signals are then boosted to increase their voltage and current levels using BJT switching mode power transistors operating in the push/pull mode. The resulting signal is then raised into the required voltage level with the aid of a step-up transformer. A practical inverter circuit has been designed and constructed to convert a 12 V battery DC input into 220 V AC output based on the 8051 microcontroller. This circuit consists of an 8051 microcontroller, buffer, driver power transistor stage, final power transistor stage, and a step-up transformer. The inverter circuit has been simulated, implemented, and tested practically. The test measurements have indicated that the circuit gives a full load power of 10 W with full-load voltage regulation of 8%, and a maximum conversion efficiency of 70%.
This paper presents an advanced power converter employs a sinusoidal voltage absolute value tracking buck–boost DC–DC converter in the first power processing stage and a polarity changing full-bridge inverter in the second stage. The... more
This paper presents an advanced power converter employs a sinusoidal voltage absolute value tracking buck–boost DC–DC converter in the first power processing stage and a polarity changing full-bridge inverter in the second stage. The proposed power conversion system has the capability of delivering good quantitative and qualitative sinusoidal output current and voltage waveforms with good output voltage regulation. Consequently, the complete voltage regulator system, which is mainly suitable for new energy generation systems as well as energy storage systems, can be constructed compactly and inexpensively without DC link electrolytic capacitor. Also, the paper presents an auxiliary passive resonant circuit for soft switching operation. Simulation results using PSIM software are presented to verify the operation principles and feasibility of the proposed power conversion system. Finally, these results are verified by means of an experimental prototype.
This paper presents a grid connected system. Three phase DC-AC inverters used to convert the regulated DC power to AC power suitable for grid connection. Third harmonic injection PWM (THIPWM) was employed to reduce the total harmonic... more
This paper presents a grid connected system. Three phase DC-AC inverters used to convert the regulated DC power to AC power suitable for grid connection. Third harmonic injection PWM (THIPWM) was employed to reduce the total harmonic distortion and for maximum use of the voltage source. DSP was used to generate the accurate THIPWM for grid connection, by synchronizing the inverter voltage with the grid voltage. The application of THIPWM to parallel connected inverter reduces the total harmonic distortion and increases efficiency of the inverter. Experimental results validate the developed model and the proposed system.
For application of PV systems, a major deterrent factor in their use is high initial investment. A focus has therefore been placed on new, cheap and innovative inverter solutions. As a result of this, a single stage inverter topology and... more
For application of PV systems, a major deterrent factor in their use is high initial investment. A focus has therefore been placed on new, cheap and innovative inverter solutions. As a result of this, a single stage inverter topology and a new configuration are proposed. In two stage circuit, the first stage takes care of MPPT and boosting the PV voltage while second stage inverts the first stage output into the required AC form. A two stage configuration has drawbacks such as high part count, lower efficiency, lower reliability, high cost and large size. These drawbacks are overcome by the circuit proposed in this paper. The new inverter circuit proposed in this paper is designed and simulated in a simulation environment. The improved topology increases the voltage, reduces the power loss and enhances the various electrical parameters. This enhancement and improvement of electrical quantities is explained with the help of different formulae and figures. With the use of this improve circuitry; the efficiency of the PV Array can be increased. The proposed inverter design and its implementation are given with operational results. Keywords — Inverters, Boost inverter, DC-AC Converter, power semiconductor switches. I. INTRODUCTION Due to the increase in industrial revolution, the world energy demand has also increased. Photovoltaic (PV) system has taken a great attention since it appears to be one of the most promising renewable energy sources. the PV solar generation is preferred over the other renewable energy sources due to the advantages such as absence of fuel cost, cleanliness, pollution free and little maintenance. Solar inverter is a critical component in a solar energy system. It converts DC power output into AC that can be fed into the grid and directly influences the efficiency and reliability of solar energy system. Grid connected PV systems have become very popular because they do not need battery backups to ensure MPPT. The grid can absorb any amount of power and so the maximum utilization of the available solar power is ensured. In this grid connected PV system, the inverter is the heart of the system which is responsible for converting DC power into the required AC power.
This paper presents a grid connected system. Three phase DC-AC inverters used to convert the regulated DC power to AC power suitable for grid connection. Third harmonic injection PWM (THIPWM) was employed to reduce the total harmonic... more
This paper presents a grid connected system. Three phase DC-AC inverters used to convert the regulated DC power to AC power suitable for grid connection. Third harmonic injection PWM (THIPWM) was employed to reduce the total harmonic distortion (THD) and for maximum use of the voltage source. the accurate generation of THIPWM minimize the THD and make the inverter suitable for grid connection, by synchronizing the inverter voltage with the grid voltage. The application of THIPWM to inverter increases efficiency of the inverter. Simulation results validate the developed model and the proposed system.
This paper is devoted to the state of the art in photovoltaic (PV) conversion chains and their architectures. Two major characteristics are considered to classify these chains. These are the galvanic isolation and the number of stages;... more
This paper is devoted to the state of the art in photovoltaic (PV) conversion chains and their architectures. Two major characteristics are considered to classify these chains. These are the galvanic isolation and the number of stages; characteristics generally localized around the DC-AC converter (inverter) at the end of the PV conversion chain. Therefore, this paper deals with a comprehensive review of the different inverter topologies that can be integrated into PV conversion chains, distinguishing between the transformer based and the transformer-less conversion chains. The paper demonstrates that to this date, transformer-based inverters are very common and widely used, have a long record of accomplishment as a component of solar energy systems, in particular for residential applications because of their greater efficiency, smaller size, and lower costs. Nevertheless, transformer-less chains are touted with some problems and shortcomings. Moreover, solar energy storage devices, wireless charging systems in stations and along the highways require the re-examination of the existing solar PV conversion chains, their architectures and possibly new conversion chains suitable for all distributed generation including electric cars and storage devices.
I attemp to review some of AC-DC Inverter from main power supply about 220 to 12 -5-0 volt.Only issues about zener diode current which is fixed with a decent low power with a low current. Another also low dc-dc converter which is have a... more
I attemp to review some of AC-DC Inverter from main power supply about 220 to 12 -5-0 volt.Only issues about zener diode current which is fixed with a decent low power with a low current.
Another also low dc-dc converter which is have a potential only between two lead mostly powered with solar panel.more safety
Fuel cells (FCs) are considered as one of the most promising sources of electrical energy that can meet environmental constraints. One of the important steps to ensure clean energy is seamless power transfer from the FC to the grid. In... more
Fuel cells (FCs) are considered as one of the most promising sources of electrical energy that can meet environmental constraints. One of the important steps to ensure clean energy is seamless power transfer from the FC to the grid. In this study, the behaviour of the FC under AC load and grid connection of FC system is simulated. Required interface for FCs' grid connection is performed with PSCAD software. For this purpose, polymer electrolyte membrane (PEM) FC model is developed in PSCAD software. Power converter units are designed to supply DC and AC loads. Control structures are developed for DC-DC converter and DC-AC inverter models in PSCAD. Power conditioning units are separately controlled by proportional-integral controller. The electrical behaviour and control of FCs are investigated and simulated using PSCAD software. Then a developed PEM FC system model is tested for AC load conditions. The PEM FC system is connected to grid and the behaviours of grid connected FC system are examined.
