Design Of High Power Factor Inverter Without Electrolytic Capacitor

In power electronic power conversion devices involving AC/DC or DC/AC conversion,the voltage and current on the AC side with sinusoidal regularity change will produce secondary fluctuating power components.Instantaneous power does not match the DC side with voltage or current straight change.It is usually necessary to connect large capacity electrolytic capacitors in parallel with DC bus,but the weakness of electrolytic capacitors in chemical properties and service life is harmful to The whole service life and stability of the system,so effective methods must be taken to remove the electrolytic capacitance.meanwhile,the harmonic pollution caused by a large number of non-linear power electronic devices connected to the power grid is also serious.Reasonable measures should be taken to improve the input power factor of the power converter.Firstly,this paper summarizes and compares the high input power factor technology and the non-electrolytic capacitor power conversion technology.On the basis of this research,the basic structure of AC/DC/AC conversion consists of the front-stage active power factor correction circuit(APFC)and the back-stage DC/AC inverters is determined.At the same time,according to the characteristics of bidirectional flow of pulsating power in DC bus of AC/DC/AC circuit,through parallelling bidirectional Buck/Boost active compensation circuit in DC bus,and adopting a new compensation control strategy without current sensor and fast response speed,the unbalanced ripple power in AC/DC/AC conversion can be well suppressed.Then,the new control is respectively applied to the Boost and Buck type parallel decoupling circuit,and the mathematical analysis is also carried out.Finally,the Design of high power factor input with electrolytic capacitor-less inverter Supply is achieved.In order to verify the effectiveness of the proposed topology and control strategy,an experimental prototype of parallel decoupled non-electrolytic capacitor inverter power supply based on AC/DC/AC transformation is designed.The experimental results verify the correctness of the theoretical analysis.