Performance optimisation of the grid‐connected flyback inverter under improved hybrid conduction mode

Abstract

In the unfolding-type interleaved two-switch flyback inverter (ILTFI) operating in discontinuous conduction mode (DCM), the hybrid control strategy combining the one-phase DCM and the two-phase DCM has a significant impact on improving the efficiency under all load conditions. In the situation where the marginal power of this control strategy is increased, the converter may enter CCM. Consequently, the converter cannot track the reference current and the output current quality is notably decreased. To tackle this issue, a novel hybrid control method is proposed which varies the switching frequency based on the output power. The proposed approach is immune to the loss analysis and power losses of the components. Hence, it is independent of components selection and their characteristics. In this case, the smooth transition between the one-phase and the two-phase operation modes is guaranteed without affecting the output power quality and the stability of the converter in DCM. The control complexity of the proposed scheme is low and the converter can be easily controlled in DCM. The performance of the flyback microinverter with the proposed hybrid control scheme is verified by the simulation and the experimental results together with the loss analysis.

A simple and highly efficient flyback inverter control strategy for AC module application

“…As a consequence, the power losses due to partial shading and PV module mismatch can be reduced [7][8][9][10][11]. Moreover, the specifications like easier maintenance and higher reliability of the ac module systems are other benefits of them [12][13][14][15][16][17]. Thus, these features make the micro-inverter a promising solution for future renewable power generation systems.…”

An Efficient Grid-tied Flyback Micro-inverter with DCM Control Strategy

“…In recent years, many technologies are proposed to design the small and efficient micro-inverter [4][5][6][7][8][9][10]. Flyback micro-inverter [11][12][13][14][15][16] represents a good attractive micro-inverter that is integrated with a single PV module.…”