Abstract

This paper presents grid-feeding type micro-inverter for a single-phase grid-interactive photovoltaic (PV) system. The system comprises of two stages, a step-up DC-DC converter with series resonant type voltage multiplier-a doubler and an inverter operating on single-switch modulation technique in order to improve efficiency of system. Use of single switch-modulating inverter helps in preventing shoot-through problem. The PV current from array is estimated without employing a DC current sensor to make system operate at maximum power point (MPP). A simulation for low power 300 W PV system without DC-current sensor maximum power point tracking (MPPT) control has been carried out to analyze cost effectiveness solution for small power rooftop applications. The simulation has been carried out on MATLAB®/Simulink platform under varying irradiation conditions to verify effectiveness of control technique and ripple present into injected grid current. The total harmonic distortion in grid current has been observed to be less than 5% even at as low as 0.25G irradiation to comply IEEE standards.

中文翻译：

---

基于直流电流传感器的无MPPT并网单相光伏（PV）微型逆变器

摘要

本文提出了一种用于单相并网光伏系统的并网型微型逆变器。该系统包括两级，具有串联谐振型电压倍增器的升压DC-DC转换器-倍增器和以单开关调制技术操作的逆变器，以提高系统效率。使用单个开关调制逆变器有助于防止直通问题。无需使用直流电流传感器就能使系统以最大功率点（MPP）运行的情况下，估算来自阵列的PV电流。针对没有直流电流传感器最大功率点跟踪（MPPT）控制的低功率300 W光伏系统进行了仿真，以分析小功率屋顶应用的成本效益解决方案。在不同的辐照条件下，在MATLAB®/ Simulink平台上进行了仿真，以验证控制技术的有效性以及注入电网电流中的纹波。即使在低至0.25的情况下，也已观察到电网电流的总谐波失真小于5％。G辐射符合IEEE标准。