This paper presents a modified SINGLE stage SINGLE PHASE inverter with four switches. The proposed inverter has important features such as continuous input current, voltage buck and boost with SINGLE stage conversion, short circuit safety and operation in various duty cycles same as qZSI and qSBI converters. In the rest of the paper, the suggested inverter operation mode and its switching method are described first and then, the steady state analysis is presented. To validate the merits of the proposed inverter, a comparison of the converter with similar topologies is provided. To verify the proper operation of the converter and also, to prove the presented theoretical calculations, a prototype of the introduced topology has been implemented in the laboratory. Test measurement results of the suggested inverter in 150 W with 10kHz frequency is derived. The obtained results and waveforms from test measurement present proposed inverter operation, steady state analysis and performance..

A new type of SINGLE-PHASE stand-alone induction generator using a three-PHASE induction machine and a SINGLE-PHASE voltage-source PWM inverter is introduced. The generator scheme is capable of producing constant load frequency with a very well regulated output voltage. A small lead acid battery and a SINGLE-PHASE full diode-bridge rectifier are used to feed the inverter. The inverter feeds one of the stator PHASEs. During the generator voltage build up, the inverter supplies the battery first and after a while a diode-bridge rectifier, which is fed by the generator, replaces if. The system steady state and dynamic equations are derived and are solved to obtain the performance characteristics of the generator scheme. A digital simulation study is carried out for a 2.2 KW three PHASE induction machine. The simulated results obtained confirm that this generator can achieve an output power of about 0.6 pu..

In this paper, a new SINGLE-PHASE SINGLE-stage high step-up boost inverter appropriate for photovoltaic systems is proposed. In the proposed inverter, the duty cycle of one of the switches is adjusted to control the output voltage and increase the gain. In this structure, the dynamic model is adopted as an appropriate model to describe the low-frequency behavior of converters and extract the equations. Moreover, in this topology, a common ground is used between the input and output which can remove leakage current in different applications, including grid-connected applications. The proposed inverter is simulated using MATLAB/SIMULINK, and the experimental results are presented to verify the theoretical analysis.

In this paper, SINGLE-PHASE dynamic comparator was improved based on adding a clocked NMOS auxiliary latch at its output and two clocked NMOS transistors at its internal nodes. Using clocked NMOS latch and transistors increased the speed of comparator, without increasing the loading effect and kick-back noise on its previous and next stages. The advantage of the proposed comparator rather than the conventional comparator was higher speed with precence same power dissipations. To demonstrate the mention specifications, proposed and conventional comparators were analyzed and simulated at 2-GS/s sampling rate in 0. 18-μ m CMOS process. In this case, the outputs of proposed comparator were determined almost 18-ps (%9) faster than the outputs of conventional comparator. Also, to compare the performances of proposed and conventional comparators in flash ADCs, two 4-bits flash ADCs, using proposed and conventional comparators in their comparison chains blocks, were designed and simulated at 2-GS/s. In this case, the FOM of ADCs with the proposed and conventional comparators at nyquist rate input frequency achieved 0. 61-pJ/conv. step and 0. 72-pJ/conv. step, respectively. Corresponding, the ENOB of ADCs achieved 3. 74-Bit and 3. 45-Bit, respectively. In addition, the power dissipations of comparators array of ADCs with proposed and conventional comparators were 4. 23-mW and 4. 09-mW, respectively. Also, the power dissipations of two flash ADCs, without the power dissipations of their comparators array, were 11. 70-mW and 12. 03-mW, respectively.

This paper presents a SINGLE-PHASE topology for multilevel inverters with minimum number of switching devices. The proposed topology significantly reduces the number of DC voltage sources, switches, and power diodes as the number of output voltage levels increases. The proposed multilevel inverter is constructed using series-connection of multilevel strings. Suggested multilevel string is composed of multiple basic switching units. The proposed multilevel inverter has extendable configuration that increases the number of output voltage levels more and more by adding more stages. The proposed multilevel inverter would be implemented in both symmetric and asymmetric configurations. Two different algorithms are introduced for determination of magnitude of DC voltage sources to reach the maximum number of output voltage levels with minimum number of semiconductor devices. Important characteristics of both symmetric and asymmetric configurations are extracted and compared with similar multilevel inverter topologies. Finally, a prototype of the proposed multilevel inverter is simulated and implemented experimentally to verify operation of the proposed multilevel inverter.

Increasing of word demand load caused a new Distributed Generation (DG) to enter to power system. One of the most renewable energy is the Photovoltaic System. It is beneficial to use this system in both separately as well as connected to power system using power electronics interface. In this paper an optimal PID controller for Photovoltaic System systems has been developed. The optimization technique is applied to PID optimal controller in order to control the voltage of Photovoltaic System against load variation, is presents. Nonlinear characteristics of load variations as plant input, Photovoltaic System operational behavior demand for high quality optimal controller to ensure both stability and safe performance. Thus, Honey Bee Mating Optimization (HBMO) is used for optimal tuning of PID coefficients in order to enhance closed loop system performance. In order to use this algorithm, at first, problem is written as an optimization problem which includes the objective function and constraints, and then to achieve the most desirable controller, HBMO algorithm is applied to solve the problem. In this study, the proposed controller is applied to the closed loop photovoltaic system behavior. Simulation results are done for various loads in time domain, and the results show the efficiency of the proposed controller in contrast to the previous controllers.