Single-phase push-pull inverter inhibiting secondary ripples

Abstract

The invention discloses a single-phase push-pull inverter inhibiting secondary ripples, and the inverter comprises a DC power supply Vin, an input filter capacitor, a main switching tube, an isolation transformer, a rectification circuit, a filter circuit, a polarity reversal inverter bridge, a load, a boost circuit, and an auxiliary switching tube. The inverter enables power ripples caused by output power to flow through an auxiliary network through the control of the power flowing direction, guarantees that input power does not comprise DC flow of frequency doubling pulse in the output power, and achieves the purpose of inhibiting the secondary ripples of a DC input side.

Description

technical field [0001] The invention relates to a single-phase push-pull inverter capable of suppressing secondary ripple. Background technique [0002] In recent years, humans have paid more and more attention to the natural environment. Clean, efficient and sustainable new energy power technologies have attracted widespread attention. Some inverter topologies and control schemes for new energy power generation have emerged. For example attached figure 1 Shown is a typical single-phase push-pull inverter. For this kind of system, the double-frequency power pulsation contained in the AC output power is fed back to the DC input side as a secondary current ripple, which will affect the service life of input sources such as batteries and fuel cells, and will interfere with the DC power supply system in severe cases. Therefore, it is urgent to solve the secondary ripple problem in the new energy power generation system and improve the utilization efficiency of new energy. Alt...

AI Technical Summary

Problems solved by technology

For this kind of system, the double-frequency power pulsation contained in the AC output power is fed back to the DC input side as a secondary current ripple, which will affect the service life of input sources such as batteries and fuel cells, and will interfere with the DC power supply system in severe cases. Therefore, it is urgent to solve the secondary ripple problem in the new energy power generation system and improve the utilization efficiency of new energy

Although connecting a large electrolytic capacitor in parallel on the DC input side can suppress the secondary ripple, if the inverter needs to work in a high temperature environment in summer, the service life of the electrolytic capacitor will be shortened sharply in a high temperature environment, which will affect the entire inverter The service life of the device

The LC resonant circuit is connected to the circuit, and the frequency of the resonant circuit is designed to be twice the output frequency, which can achieve the purpose of suppressing the secondary ripple, but the volume of the inductor and capacitor required to filter out the low-frequency ripple is relatively large, reducing the system reliability and power density

An active filter can also be connected to the circuit, but the additional circuit will inevitably require an additional control system, making the whole system more complicated and not conducive to integration

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