High Step up Dc-Dc Converter For Distributed Power Generation

ABSTRACT: This paper presents, a high voltage gain DC-DC converter for distributed generation (DG) systems with MPPT controller. A high step-up ratio and clamp-mode converter are proposed to achieve high voltage gain and high efficiency. This can be obtained by using two capacitors and one coupled inductor. During the switch-off period, the capacitors are charged in parallel and during the switch-on period they are discharged in series by the energy stored in the coupled inductor. A passive clamp circuit is used to recycle the leakage inductor energy of the coupled inductor, thus voltage stress on the main switch is reduced. The control method for the circuit is implemented using a MPPT controller which tracks the maximum power of the sources. The converter is suitable for high power applications because of the reduced conduction loss and low input current ripple. The operating principle and MATLAB simulations are discussed in detail

High step up DC-DC converter topology for PV systems and electric vehicles

This thesis presents new high step-up DC-DC converters for photovoltaic and electric vehicle applications. An asymmetric flyback-forward DC-DC converter is proposed for the PV system controlled by the MPPT algorithm. The second converter is a modular switched-capacitor DC-DC converter, it has the capability to operate with transistor and capacitor open-circuit faults in every module. The results from simulations and tests of the asymmetric DC-DC converters have suggested that the proposed converter has a 5% to 10% voltage gain ratio increased to the symmetric structures among 100W – 300W power (such as [3]) range while maintaining efficiency of 89%-93% when input voltage is in the range of 25 – 30 V. they also indicated that the softswitching technique has been achieved, which significantly reduce the power loss by 1.7%, which exceeds the same topology of the proposed converter without the softswitching technique. Moreover, the converters can maintain rated outputs under main transistor open circuit fault situation or capacitor open circuit faults. The simulation and test results of the proposed modularized switched-capacitor DC-DC converters indicate that the proposed converter has the potential of extension, it can be embedded with infinite module in simulation results, however, during experiment. The sign open circuit fault to the transistors and capacitors would have low impact to the proposed converters, only the current ripple on the input source would increase around 25% for 4-module switched-capacitor DC-DC converters. The developed converters can be applied to many applications where DC-DC voltage conversion is alighted. In addition to PVs and EVs. Since they can ride through some electrical faults in the devices, the developed converter will have economic implications to improve the system efficiency and reliability

Power Quality Enhancement in Grid Connected PV Systems using High Step Up DC-DC Converter

Renewable energy sources (RES) are gaining more importance in the present scenario due to the depletion of fossil fuels and increasing power demand. Solar energy is the one of the most promising as it is clean and easily available source. The voltage obtained from the PV system is low. This voltage is increased by high step up dc-dc converter which uses only one switch leads to low switching losses and hence the efficiency of this converter is high. To get the good response this converter is operated in closed loop manner. Integration of PV system with existing grid has so many issues like distorted voltage, current and reactive power control etc. This paper presents a four leg inverter which works on hysteresis current control technique to address the power quality issues like reactive power compensation, balanced load currents and compensation of neutral current. The switching to the inverter is designed in such a way that it supplies the extra current to stabilise the current of the grid that is being supplied to the loads. Finally, the proposed technique is validated by using mat lab/Simulink software and corresponding results are presented in this paper

A New Multilevel Inverter Topology For High Step Up DC-DC Converter

High step up proportion dc–dc converters with megawatt evaluations are of enthusiasm for wind turbine interfaces and high-voltage direct current frameworks. This paper introduces a secluded multilevel dc–dc converter in view of the standard boost converter topology yet with the typical single switches supplanted by various capacitor-cinched sub modules. The converter is worked in resounding mode with reverberation between sub module capacitors and the arm inductor. A phase-shifted switching  course of action is connected with the end goal that there is a consistent number, i.e., N, of sub modules supporting the high voltage at once. In this operation mode, the progression up proportion is reliant on the quantity of sub modules and the inductor charging proportion. The converter shows versatility without utilizing a transformer and is equipped for bidirectional power stream. This venture is reached out to next sub module for expanding working scope of the converter. The outcomes checked through MATLAB/SIMULINK condition

Interleaved High Step-up DC-DC Converter with Diode-Capacitor Multiplier Cell and Ripple-Free Input Current

In this paper interleaving and switched-capacitor techniques are used to introduce a high step-up DC-DC converter for renewable energy systems application. The proposed converter delivers high voltage gain without utilizing transformer or excessive duty cycle and features ripple-free input current which results in lower conduction losses and decreased electromagnetic interference (EMI). Lower output capacitance is another advantage of proposed converter, leading to smaller size and lower cost. Furthermore lower voltage stress on switches allows the utilization of switches with low resistance. Simulation results verify the performance of suggested converter

Interleaved High Step-up DC-DC Converter with Diode-Capacitor Multiplier Cell and Ripple-Free Input Current

In this paper interleaving and switched-capacitor techniques are used to introduce a high step-up DC-DC converter for renewable energy systems application. The proposed converter delivers high voltage gain without utilizing transformer or excessive duty cycle and features ripple-free input current which results in lower conduction losses and decreased electromagnetic interference (EMI). Lower output capacitance is another advantage of proposed converter, leading to smaller size and lower cost. Furthermore lower voltage stress on switches allows the utilization of switches with low resistance. Simulation results verify the performance of suggested converter

Performance Enhancement of High Step-up DC-DC Converter to Attain High Efficiency and Low Voltage Stress

This study proposes a new high voltage gain and high-efficiency DC-DC converter to interface renewable energy resources into dc nanogrid. The proposed topology is formed by a coupled inductor to achieve high voltage gain and low stress on the active switch. The switch voltage stress is significantly low compared to the output voltage. Thus, efficiency is improved by utilizing a low voltage rating MOSFET. Furthermore, the utilization of couple inductor eliminated the reverse recovery losses of diodes. The converter consists of the least number of components that decrease the overall system cost. The steady-state operation and analysis of the proposed converter are discussed comprehensively. The experimental performance is verified by building and testing a prototype in the laboratory. The experimental results prove the consistency with the theoretical analysis. The converter depicts a peak efficiency of 97.10% in the laboratory

A High Step-Up Dc-Dc Converter using a Three Winding Coupled Inductor for Photovoltaic to Grid Applications

A dual-switch high step-up DC-DC converter topology is proposed in this paper. The proposed topology uses two power switches, a three-winding coupled inductor (TWCI), and voltage multiplier cells to provide a high voltage gain. Furthermore, the voltage stresses on power semiconductor switches are low, resulting in lower switching and conduction losses. Moreover, the common electrical ground is preserved in this topology, making it a suitable candidate for photovoltaic (PV) to grid systems. The operating modes and steady state analysis of the proposed converter are presented, and a comparative study is carried out to demonstrate advantages of the proposed topology over the existing topologies. Finally, the simulation results of the proposed topology are presented using PLECS software along with the experimental results for a 200 W, 30 V to 400 V laboratory setup