PROJECT TITLE:

On the Reduction of Second Harmonic Current and Improvement of Dynamic Response for Two-Stage Single-Phase Inverter - 2015

ABSTRACT:

2-stage single-section inverters have been widely used as they'll achieve voltage matching and galvanic isolation between the input and output. Because of the pulsating output power of the downstream inverter, an ac current at twice the output frequency, which is named second harmonic current (SHC), arises within the input aspect of the downstream inverter. This SHC can penetrate to the front-finish dc-dc converter, leading to reduced conversion potency. This paper first analyzes the propagation mechanism of the SHC and load transient response of 2-stage single-phase inverters from the perspective of output impedance. Then, based mostly on this mode control and load current feed forward, two management strategies to realize low SHC in the front-end dc-dc converter and fast dynamic performance during load transient are proposed in this paper. Finally, a 2-kW two-stage single-section inverter prototype has been constructed and tested, and the experimental results are provided to verify the effectiveness of the proposed control strategies.