The Components of Solar Panel System for Home

The solar panel system for home is composed of solar cell array, battery pack, charge and discharge controller, inverter, AC distribution cabinet, automatic solar tracking system, automatic solar module dust removal system and other equipment.

The functions of each part of the equipment are:

1. Solar cells

In the presence of light (whether it is sunlight or light generated by other luminous objects), the battery absorbs light energy, and there is an accumulation of charges with different signs at both ends of the battery, which generates a "Photo-voltage", which is the "photovoltaic effect". Under the action of the photovoltaic effect, the two ends of the solar cell generate electromotive force and convert light energy into electrical energy. It is an energy conversion device.

Solar cells are generally silicon cells, which are divided into three types: mono-crystalline silicon solar cells, poly-crystalline silicon solar cells and amorphous silicon solar cells.

2. Battery pack

Its function is to store the electric energy emitted by the solar cell array when it is exposed to light and to provide power to the load at any time.

The basic requirements for the battery pack used in solar cell power generation are:

a. Low self-discharge rate;

b.Long service life;

c. Strong deep discharge capability;

d. High charging efficiency;

e. Little or no maintenance;

f. Wide operating temperature range;

g. Low price.

The batteries currently used in conjunction with solar panel system for home are mainly lead-acid batteries and cadmium-nickel batteries. For lead-acid batteries above 200Ah, fixed or industrial sealed maintenance-free lead-acid batteries are generally used. The rated voltage of each battery is 2VDC. For lead-acid batteries below 200Ah, small sealed maintenance-free lead-acid batteries are generally used. The rated voltage of each battery is 12VDC.

With the development and application of lithium batteries in recent years, lithium iron phosphate batteries have also become another option for batteries in solar panel system for home.Compared with traditional lead-acid batteries, it can be charged and discharged more than 6,000 times and has a longer service life. At the same time, it also costs more.

3. Charge and discharge controller

It is a device that can automatically prevent battery overcharging and over-discharging. Since the number of charge and discharge cycles and depth of discharge of the battery are important factors that determine the service life of the battery, a charge and discharge controller that can control the overcharge or over discharge of the battery pack is an essential device.

4. Inverter

It is a device that converts direct current into alternating current. Since solar cells and batteries are DC power sources and the load is AC load, an inverter is essential.

According to the operating mode, inverters can be divided into independent operating inverters and grid-connected inverters. Stand-alone inverters are used in stand-alone solar cell power generation systems to supply power to independent loads. Grid-connected inverters are used in solar cell power generation systems that operate on the grid.

Inverters can be divided into square wave inverters and sine wave inverters according to the output wave type. The square wave inverter has a simple circuit and low cost, but has a large harmonic component. It is generally used in systems below a few hundred watts and with low harmonic requirements. Sine wave inverters are expensive but can be adapted to a variety of loads.

Inverter protection function:

a. Overload protection;

b. Short circuit protection;

c. Reverse connection protection;

d. Under voltage protection;

e. Over voltage protection;

f. Overheating protection.

5. AC power distribution cabinet

Its main function in the power station system is to switch the backup inverter to ensure the normal power supply of the solar panel system for home, and also to measure the line power.