**3.2 Reconfigurable PV module**

It is shown in different research work the ways different fixed PV cell topologies mitigate the effect of partial shading and mismatch [28–31]. The usage of bypass diode achieves the effectiveness of fixed topologies. However, a fault in the bypass diodes can make various topologies for creating PV modules ineffective. Compared to using bypass diode, a novel complementary metal-oxide-semiconductor (CMOS) switch embedded PV module is proposed [32]. Thus having CMOS based switches the PV modules configuration, i.e., the number of PV cells in series vs. the number of PV cells in parallel, can be changed in real time [12, 32] in case of a fault in PV cells or partial shading condition. A CMOS embedded PV module is shown in **Figure 9**. The circuit diagram of the switches used is presented in detailed in [33].

In [27], it is presented that reconfigurable PV modules are much better in tackling the effect partial shading condition. However, it is also shown on the resistance of metal oxide semiconductor field-effect transistor (MOSFET) can reduce the

**Figure 7.**

*The PV module connected in BL topology. a) the configuration of PV module is 4 × 5 b) I-V characteristics of PV module c) P-V characteristics of PV module under different shading condition.*

#### **Figure 8.**

*The PV module connected in HC topology. a) the configuration of PV module is 4 × 5 b) I-V characteristics of PV module c) P-V characteristics of PV module under different shading condition.*

#### **Figure 9.**

*CMOS switch embedded PV module. A group of four transistors are connected in series by turning ON and OFF CMOS based transistors.*

effectiveness of the CMOS embedded PV module. Hence, it is a necessity to develop a modeling technique for reconfigurable PV modules for further development and deployment of their usage in various applications. Three different types of MOSFETs are used for modeling the reconfigurable, which is presented in **Table 2** [12].

The array decomposition for modeling the CMOS embedded PV module is shown in **Figure 10**. For simplicity, the two diodes are combined into a single diode shown in **Figure 10**. The total current generated by the reconfigurable PV module in configuration Ns × Np (number of PV cells in series x number of PV cells in parallel) is given by [33]:

$$I\_{PV} \approx N\_p \left[ I\_{ph} - I\_{d1} - I\_{d2} - \frac{B}{R\_P} \right] \tag{6}$$

$$I\_d = I\_s \left( \mathbf{e}^{\left(\frac{B}{\mathbf{A} \times \mathbf{V}\_T}\right)} - \mathbf{1} \right) \tag{7}$$

**27**

**Figure 11.**

*PV cells in series x number of PV cells in parallel).*

*Modeling of Photovoltaic Module*

**Table 2.**

**Figure 10.**

*DOI: http://dx.doi.org/10.5772/intechopen.97082*

*CMOS transistors resistance variable name and values.*

*PV cell decomposition technique for modeling CMOS embedded PV module.*

*The maximum power under different shading patterns over PV module for different configurations (number of* 

**Symbol Description Value and units**

RPs ON resistance of P-type MOSFET transistor 1mΩ RT ON resistance of transmission gate transistor 1mΩ Rns ON resistance of N-type MOSFET transistor 1mΩ

$$B = \frac{\upsilon\_{pv}}{N\_S} + i\_{pv} \left( \frac{R\_S}{N\_P} + \frac{\left(N\_S - 1\right) \cdot R\_T}{N\_P \cdot N\_S} + \frac{2 \cdot R\_m}{\left(N\_P - 1\right) \cdot N\_S} \right) \tag{8}$$

In Eq. (8), the Rns is equal to RPS. It is possible to achieve it by sizing the N-type and P-type MOSFET transistor's width based on the process transconductance. The
