The solar generator systems consists of solar panels, solar controllers, and batteries. If the output power is AC 220V or 110V, an inverter is also required. The functions of each part are:
Solar panels are the core part of the solar power generation system. Its function is to convert the sun’s radiant energy into electrical energy, then store it in the storage battery, or push the load to work. The quality and cost of the solar panel will directly determine the quality and cost of the entire system.
The solar controller is composed of a special processor CPU, electronic components, displays, switching power tubes, etc. Its function is to control the working status of the entire system, and avoid battery overcharging or overdischarging. In places with large temperature differences, qualified controllers should also have the function of temperature compensation. It also should have other additional functions such as light control switch and time control switch etc.
Generally lead-acid batteries, nickel metal hydride batteries, nickel cadmium batteries or lithium batteries can also be used in small systems. Since the input energy of the solar photovoltaic power generation system is extremely unstable, it is generally necessary to configure a battery system to work. Its function is to store the electric energy from solar panels when sunny day, and release it when needed.
More information can be found in another article, “Solar Gel Battery and Their Competitors“
In many occasions, it is necessary to provide 220VAC and 110VAC AC power. Since the direct output of solar energy is generally 12VDC, 24VDC, or 48VDC, in order to provide power to 220VAC electrical appliances, it is necessary to convert the DC power into AC, So a DC-AC inverter is required. In some occasions, when loads with multiple voltages , a DC-DC inverter is also needed, such as converting 24VDC power into 5VDC power.
During the day, the solar cell modules generate a certain electromotive force, and form a solar cell square array through the series and parallel connection of the modules, so that the voltage of the square array meets the requirements of the system input voltage. Then the storage battery is charged through the charge and discharge controller, so the electric energy converted from light energy is stored.
At night, the battery pack provides input power to the inverter. Through the inverter, the DC power is converted into AC power, which is sent to the power distribution cabinet. The power is supplied by the switching function of the power distribution cabinet. The discharge of the battery pack is controlled by the controller to ensure the normal use of the battery. The photovoltaic power station system should also have limited load protection and lightning protection devices , which will protect the system equipment from overload and lightning strikes, then maintain the safe use of system equipment.
Solar generator systems are mainly divided into four categories according to its application .
Off- grid solar generator system, which is especially suitable for application in areas with no electricity shortage; the off grid solar power systems is also called an independent photovoltaic system. The photovoltaic power generation system is not connected to the public grid. Its typical feature is to use solar energy to generate electricity during the day, store the electrical energy in energy storage devices such as batteries, and release electrical energy to related electrical equipment when needed.
Solar off grid power systems are generally composed of solar cell arrays, off-grid controllers, battery packs, and off-grid inverters. The system structure is shown in the figure below:
On- grid solar generator system, which has been widely promoted and implemented in developed countries; the on-grid solar system generally consists of solar cell arrays, on-grid inverters and some electrical equipment (combiner boxes, power distribution cabinets, etc.). The structure of this system is shown in the figure below:
Hybrid solar generator system and other energy sources; the photovoltaic hybrid solar system refers to other power supply equipments except photovoltaics generation system. Such as wind power photovoltaic power generation complementary system (referred to as wind-solar hybrid system), photovoltaic and mains complementary system, photovoltaic and diesel engine complementary system, wind-solar and diesel-electric complementary system, etc. The hybrid solar system can be applied in many fields, can avoid each other’s deficiencies of individual power generation systems, and improve the stability of the power generation system.
The fourth is solar energy application products, such as solar chargers, various solar lamps, photovoltaic water pumps, etc. In fact, the scale of photovoltaic systems spans a large range, ranging from 0.3-2 watt photovoltaic application products to megawatt-level solar photovoltaic power plants. Photovoltaic systems can be used in any field and provide green power to humans in various ways.
1) Cleaning the solar panels every half a month. The maintenance of photovoltaic panels is mainly to check whether the solar power supply system and battery packs are all in normal status.
2) Check each solar panel and solar system wiring and wiring connections, and whether each group of photovoltaic panels is working normally.
3) Check the connections of the solar cells of the photovoltaic panel, templates, molded glass, and frames whether have looseness and damage. The situation should be recorded in the maintenance/repair log. If damaged, replace immediately or plan for replacement.
4) When the surface of photovoltaic panels is cleaned, it can increase the power generation of the system, so we could increase the frequency of cleaning.
The maintenance of the steel bracket is mainly to check whether there is any rust on it. If yes, remove the rusted from the surface, then paint with anti-rust paint. Check whether there are any screws loosen , if yes, tighten the screws immediately.
