Single-stage single-phase current type inverter with high step-up ratio

Abstract

The invention relates to a single-stage single-phase current type inverter with a high step-up ratio, belonging to the power electronic technology. The inverter comprises an energy storage inductor having a central tap, a single-phase inverting bridge and a single-phase filter in order cascade connection; an energy storage switch is connected between the central tap of the energy storage inductorand the input DC power supply; the input DC power supply, the energy storage inductor and the energy storage switch form a magnetizing loop; the single-phase inverting bridge comprises a two-phase power-limiting switches for bearing two-way voltage stress and one-way current stress. The inverter can convert unstable DC into stable and excellent single-phase output AC, and has the advantages of single-stage power conversion, high power density, high conversion efficiency, high step-up ratio, low distortion degree of output wave shape, high reliability in overloading and short circuit, low costand the like; the inverter is suitable for the step-up, middle and small capacity single-phase passive and grid-connected inverting occasions; and the inverter further shows unique advantages along with the appearance of novel components such as two-way blocking IGBT and the like.

Description

technical field [0001] The present invention relates to a single-stage, single-phase, large-boost-ratio current-type inverter, which belongs to the power electronics technology. Background technique [0002] The inverter is a static conversion device that uses power semiconductor devices to convert direct current into alternating current, which is used for AC loads or connected to the public grid for power generation. [0003] Due to the increasing shortage of fossil energy (non-renewable energy) such as oil, coal and natural gas, serious environmental pollution, global warming, nuclear energy production will produce nuclear waste and pollute the environment, energy and the environment have become major issues facing mankind in the 21st century . Renewable energy (green energy) such as solar energy, wind energy, tidal energy and geothermal energy has the advantages of being clean, pollution-free, cheap, reliable, and abundant. People are paying more and more attention to th...

AI Technical Summary

Problems solved by technology

When this type of inverter works normally, the DC side voltage must be greater than the peak value of the AC side phase voltage, so there is an obvious defect: when the DC side voltage (such as the output capacity of photovoltaic cells) decreases, such as rainy days or nights, the entire power generation The system will stop functioning and the utilization of the system will drop

In this regard, the following two methods are often used to solve this problem: (1) Add a Boost DC converter to the front stage to form a two-stage power conversion circuit structure, which increases the complexity, loss and cost of the circuit; (2) ) output plus a single-phase power frequency transformer, which greatly increases the volume, weight and cost of the system, especially difficult to adapt to today's sharp rise in the price of copper and iron raw materials

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