چكيده به لاتين
The shortage of conventional fossil fuels and the environmental problems has been calling for the search and utilization of renewable energy sources and electric vehicles. Among them, Bidirectional DC-DC converters (BDC) converters have taken more attention for their usage in Plug-In Hybrid Electric Vehicles (PHEV), Photovoltaic (PV) system, Fuel Cell, Uninterruptible Power Supplies (UPS) in recent years. The BDCs can be classified into isolated and non-isolated types. The non-isolated BDCs have attracted special interest due to esay control and simple structure ,but in cases where there are large differences between the two high and low voltages, they are not suitable due to multiple problems. Therefore, in order to increase gain voltage the high step-up/step-down converters have been introduced. To increase the voltage gain have been proposed the coupled-inductor, interleaved, switching capacitor topology, and hybrid methods. Since these converters are commonly used as the interconnect between the high-voltage DC bus and the energy storage element, such as the battery, the lack of charge / charge discharge current is one of the main factors affecting their lifespan and their health. Also, by various soft-switching techniques can be applied to reduce the switching loss and increase the power density. It should be noted that in these exchangers, the creation of soft-switching conditions with the least possible element, which has both optimized efficiency / efficiency performance, is one of the design challenges.
Design and simulation of a new non-isolated high step-up bidirectional converter is proposed for Energy Storage Systems in this research. The Analysis of a 500W, 24V/400V is realized. The detailed analysis is discussed in this research. The interleaved structure is applied to achieve the current sharing characteristic. In addition to reducing the current stress of the component, the current ripple of the circuit can also be decreased. In order to decrease the semiconductors voltage stress and to improve the high voltage gain, this converter uniting the coupled inductor. Moreover, the active clamp circuits are employed to suppress the primary main switch turn-off voltage spikes and to recycle the leakage energy. All the switches can achieve ZVS soft switching performance. Through simulation, the validity and property of the proposed converter can be verified. Finally, by referring to the contents and results presented, while presenting the overall conclusion, the suggestions that can be considered in future research are discusse.
Keywords: Bi-directional dc-dc converter ,high step-up/step-down converters ,soft switching techniques ,interleaved ,coupled inductor.
