A power conversion circuit

Abstract

The invention discloses a power conversion circuit, which includes an input DC source, a DC conversion unit, an AC conversion unit, and a filter unit. The DC conversion unit is used to output a DC bus voltage according to a DC power supply, wherein the DC bus voltage is higher than that of the DC power supply. Voltage; the AC conversion unit accepts the DC bus voltage and outputs an AC voltage and an AC current; the filter unit filters the ripples of the AC current and the AC voltage to provide smooth AC voltage and AC current to the load. The power conversion circuit of the present invention makes the voltage stress of the switch tube smaller, and uses fewer switch tubes than the traditional two-stage scheme, reduces the conduction loss and the turn-off loss of the switch tube, and improves the efficiency of the entire converter.

Description

technical field [0001] The invention relates to the technical field of electric energy conversion, in particular to a power conversion circuit. Background technique [0002] With the increasing emphasis on energy saving and environmental protection, new energy power generation is widely used. However, due to the influence of external environment and other factors, new energy power generation systems such as solar / wind energy have a wide output voltage range, and their electromagnetic working environment is harsh. Equipped with a high-efficiency and high-reliability DC-AC conversion device with high boosting capacity, the new energy output voltage is converted into an AC voltage with a voltage frequency that meets the requirements. The traditional DC-AC conversion circuit has low reliability in the electromagnetic interference environment due to the bridge arm through problem, and its AC output voltage needs to be lower than the DC input voltage, which cannot meet the above w...

AI Technical Summary

Problems solved by technology

[0002] With the increasing emphasis on energy saving and environmental protection, new energy power generation is widely used. However, due to the influence of external environment and other factors, new energy power generation systems such as solar / wind energy have a wide output voltage range, and their electromagnetic working environment is harsh. Equipped with a high-efficiency and high-reliability DC-AC conversion device with high boosting capacity, the new energy output voltage can be converted into an AC voltage whose voltage frequency meets the requirements

The traditional DC-AC conversion circuit has low reliability in the electromagnetic interference environment due to the problem of bridge arm straight-through, and its AC output voltage needs to be lower than the DC input voltage, which cannot meet the above working requirements

[0003] The existing solution is to add an AC transformer or a DC converter to the DC-AC circuit to achieve the step-up function, but the AC transformer is bulky and heavy, and the implementation cost is high, and the two-stage structure of the DC converter makes the system complex. And affect the efficiency, and their reliability has not been improved; the existing unipolar converters such as impedance source converters have boosting capability and high reliability, but the boosting work needs to use the bridge arm through state, the switch tube High current stress and conduction losses, low system efficiency, and only suitable for three-phase AC output applications

Images