This paper presents a modular grid-connected single-phase system based on series-connected current-source module integrated converters (MICs). The modular configuration improves the reliability, redundancy and scalability of photovoltaic (PV) distributed generators. In this system, each PV panel is connected to a dc/ac inverter to permit individual Maximum Power Point Tracking (MPPT) operation for each panel. Thus, the harvested power from the PV system will increase significantly. There are four different inverter topologies suitable to be used as MICs with different performances in terms of filtering elements size, power losses, efficiency, output voltage range, and high frequency transformers’ size. For the MPPT control, the oscillating even order harmonic components should be eliminated from the inverter’s input side otherwise the maximum power cannot be extracted. The proposed modulation scheme in this paper will ease the control of inverter’s input and output sides. Therefore, the 2nd order harmonic in the input current can be eliminated without adding new active semiconductor switches. A repetitive controller coupled with proportional-resonant controllers are employed to achieve accurate tracking for grid side as well as input side currents. Comparisons and performance evaluations for the proposed MICs are presented and validated with 1 kVA prototype controlled by TMS320F29335 DSP.

中文翻译：

---

用于光伏并网应用的电流源单相模块集成逆变器

本文介绍了一种基于串联电流源模块集成转换器 (MIC) 的模块化并网单相系统。模块化配置提高了光伏 (PV) 分布式发电机的可靠性、冗余性和可扩展性。在该系统中，每个光伏电池板都连接到一个直流/交流逆变器，以允许每个电池板单独进行最大功率点跟踪 (MPPT) 操作。因此，从光伏系统收集的功率将显着增加。有四种不同的逆变器拓扑结构适合用作 MIC，在滤波元件尺寸、功率损耗、效率、输出电压范围和高频变压器尺寸方面具有不同的性能。对于 MPPT 控制，逆变器输入侧的振荡偶次谐波分量应消除，否则无法提取最大功率。本文提出的调制方案将简化逆变器输入和输出侧的控制。因此，无需添加新的有源半导体开关即可消除输入电流中的二阶谐波。重复控制器与比例谐振控制器相结合，用于实现对电网侧和输入侧电流的精确跟踪。通过由 TMS320F29335 DSP 控制的 1 kVA 原型展示并验证了建议的 MIC 的比较和性能评估。无需添加新的有源半导体开关即可消除输入电流中的二阶谐波。重复控制器与比例谐振控制器相结合，用于实现对电网侧和输入侧电流的精确跟踪。通过由 TMS320F29335 DSP 控制的 1 kVA 原型展示并验证了建议的 MIC 的比较和性能评估。无需添加新的有源半导体开关即可消除输入电流中的二阶谐波。重复控制器与比例谐振控制器相结合，用于实现对电网侧和输入侧电流的精确跟踪。通过由 TMS320F29335 DSP 控制的 1 kVA 原型展示并验证了建议的 MIC 的比较和性能评估。