Solar Cell

Md Imtiaz Uddin (11010338)Raihanul Islam (11010156)

W e l c o m e t o p r e s e n t a t I o n a b o u t

What is solar cell?

Solar cells are in fact large areasemiconductor diodes.

Due to photovoltaic effectenergy of light (energy ofphotons) converts intoelectrical current.

Figure 1.1: a solar cell

Solar Cell Features

Crystalline solar cellsoMono crystalline siliconoPolycrystalline siliconoRibbon siliconoMono-like-multi silicon (MLM)

Amorphous solar cells

Figure 1.2: Crystalline solar cell

Figure 1.2: Amorphous solar cell

Solar Cell Operation

Photo voltaic is the direct conversion of light into electricity at theatomic level. Some materials exhibit a property known as thephotoelectric effect that causes them to absorb photons of light andrelease electrons. When these free electrons are captured, an electriccurrent results that can be used as electricity.

When light energy strikes the solar cell, electrons are knockedloose from the atoms in the semiconductor material. If electricalconductors are attached to the positive and negative sides, forming anelectrical circuit, the electrons can be captured in the form of anelectric current -- that is, electricity. This electricity can then be used topower a load, such as a light or a tool.

Figure 3.1: Solar cell configure

Solar Cell Operation (cont…)

Figure 3.2: an animation about solar cell operation

Important terms of Solar Cell

Figure 4.1: important terms of solar cell

AGM (Absorbed Glass Mat)AlternatorAmorphous SemiconductorAmp HourBackup EnergyCell (battery)Cell (solar)CircuitFull SunInverter (AC)Kilowatt-Hour (KWH)Maximum Power Point Tracking (MPPT)Peak WattPhotovoltaic Cell

Maximum power point tracking (MPPT) is a technique that grid connected inverters, solarbattery chargers and similar devices use to get the maximum possible power from one or morephotovoltaic modules.

Solar inverters convert the DC power to AC power and may incorporate MPPT: such inverterssample the output power (I-V curve) from the solar modules and apply the proper resistance(load) so as to obtain maximum power.

MPP(Maximum power point) is the product of the MPP voltage(Vmpp) and MPP current(Impp).

MPPT ( Maximum Power Point Tracking )

Perturb and observeIncremental conductanceCurrent sweepConstant voltage

Classification

MPPT ( Maximum Power Point Tracking )

Panel tracking - this is where the panels are on a mount that followsthe sun.

These optimize output by following the sun across the sky formaximum sunlight.

These typically give us about a 15% increase in winter and up to a35% increase in summer.

This is just the opposite of the seasonal variation for MPPTcontrollers.

Maximum Power Point Tracking is electronic tracking - usually digital.the charge controller looks at the output of the panels, and comparesit to the battery voltage.

It takes this and converts it to best voltage to get maximum AMPSinto the battery.

Most modern MPPT's are around 93-97% efficient in the conversion.

Figure 5.1: a MPPT display

Solar Cell Characteristics

There have four characteristics of solar cell by depend ondifferent irradiation and temperature values. Which are-

Solar cell I-V characteristics for different irradiation values

Solar cell Power characteristics for different irradiation values

Solar cell I-V characteristics for temperature dependency

Solar cell Power characteristics for temperature dependency

Solar Cell Characteristics (cont…)

Figure 2.1: Solar cell I-V characteristics for different irradiation values

Figure 2.2: Solar cell Power characteristics for different irradiation values

Solar Cell Characteristics (cont…)

Figure 2.3: Solar cell I-V characteristics for temperature dependency

Figure 2.4: Solar cell Power characteristics for temperature dependency

Some of MPPT digital devices

Figure 5.4: SunSaver MPPT

Figure 5.3: TriStar MPPT

Figure 5.2: TriStar MPPT 600V

Thank’s all