*1.3. Paper Structure*

This paper is organized as follows. The first section presented an introduction, including the motivation for the research and the specific research questions. The second section addresses system-level criteria for BIPV installations. A comparison between the different electrical architectures is given in section three. The fourth section will translate the system-level criteria into specific converter requirements and discuss relevant fault-tolerance and safety aspects more in-depth. The last section concludes this paper.

#### **2. System Criteria for BIPV**

This section describes the important system criteria that relate to the electrical installation of BIPV systems. These criteria serve as key performance indicators (KPIs) to evaluate the different interconnection methods, as shown in Figure 1. The next section will evaluate the different methods based on the derived KPIs.

**Figure 1.** The possible electrical architectures for PV module interconnection to an AC or DC grid: (**a**) string inverters; (**b**) micro-inverters; (**c**) series power optimizer; and (**d**) parallel power optimizer.
