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DEE-53117 Solar Power Systems
Examination, 1.11.2017

Answer to each guestion 1, 2, 3 and 4 should fit into one page of a common writing paper.

a)
b)
c)

b)

How and why does solar radiation vary daily and annually on the northern hemisphere?

What is the type and structure of the most common PV panel (module) type in the market?
What has been the market share of solar PV power plants in new installed capacity of
electricity production globally and in European Union during the past few years?

Draw the change in % of open circuit voltage, short circuit current and maximum power as a
function of temperature from -20 to 80 * for a crystalline silicon photovoltaic cell.

What is the basic difference in absorption of photons between silicon and thin film
photovoltaic cells and what is the reason for that?

PV system includes 30 series connected identical PV modules, which have a short circuit current
of 10 A, open circuit voltage of 12.5 V and maximum power of 95 W in standard test conditions
(STC). One bypass diode is connected in antiparalle] with series connected monocrystalline silicon
PV cell in the PV module to protect cells.

a)

b)

a)

b)
c)

d)
e)

Draw current and power of one PV module as a function of voltage, when it receives 1 kW/m?
irradiance at 25 and 55 *C temperature.

Draw current and power of the series connected PV system as a function of voltage, when 10
PV modules receive an irradiance of 200 W/m?, 18 an irradiance of 800 W/m? and the rest an
irradiance of 1.2 kW/m?. All PV modules are at STC temperature.

What electrical guantity is common for PV module strings connected in parallel and what is
cumulative?

How does voltage behave when identical PV cells are connected in series?

What is the share of solar PV power production capacity of the total electricity production
capacity worldwide?

Define the guantity charging capacity of a PV panel (module).

Define the guantity fill factor.

Why a lightning protection is not usually need for a PV power system installed on a rooftop
of a private detached house?