University of South Wales Master of Sciences Thesis
tải về 6.62 Mb. Chế độ xem pdf
|
| 2.2.5. PV Array specification
PV cells produces around 0.5V and it is the smallest unit of the solar PV system. Cells are further connected in series or/and parallel combination to form a PV array. The power-voltage and current- voltage characteristics of 330 SunPower modules (SPR-305) PV model are obtained according to the value of the variables �ph, �o, �sh, and ��. The value of the variables are collected from manufacture datasheet and are shown in the appendices, they usually provide values for �PV and �PV at open circuit, short circuit, and maximum power point and finally the number of the PV cells. The current-voltage and power-voltage characteristics of a solar PV module operating at a standard temperature of 25 ∘ C and different solar irradiance are shown in Figures 2.6 and 2.7. According to solar irradiation or load current, the maximum output power of the PV module varies. Therefore, a proper control system is needed to use the PV model more efficiently as an electric power source by building a MPPT. There are many different MPPT methods discussed in [12,15], among them perturbation and observation method (P&O) is most widely used because it is much simpler and needs fewer measured variables. The 100-kW PV array of the detailed model uses 330 SunPower modules (SPR-305). The array consists of 66 strings of 5 series-connected modules connected in parallel (66*5*305.2 W= 100.7 kW). Standalone hybrid generation system for the remote area of Thar, Pakistan Manufacturer specifications for one module are: - Number of series-connected cells: 96. - Open-circuit voltage: Voc= 64.2 V. - Short-circuit current: Isc = 5.96 A. - Voltage and current at maximum power: Vmp =54.7 V, Imp= 5.58 A. The characteristics of the SunPower-SPR305 array are shown below. Fig. 2.6 I-V characteristics of the PV- Array Fig. 2.7 P-V characteristics of the PV- Array Dot on blue curve indicate module manufacturer specifications (Voc, Isc, Vmp, Imp) under standard test conditions (25 degrees Celsius, 1000 W/m2). tải về 6.62 Mb. Chia sẻ với bạn bè của bạn:
|