Composition of photovoltaic power generation monitoring system

1. Solar cell module

Solar cell module, also known as solar panel, is the core part of solar photovoltaic power generation system and the most valuable part of solar power generation system. Its function is to convert the radiation energy of sunlight into electrical energy and send it to the battery for storage, or it can be directly used to drive the load. When the power generation capacity is large, multiple battery modules need to be connected in series and parallel to form a solar cell array. The solar cells currently used are mainly crystalline silicon cells, which are divided into single crystal silicon solar cells, polycrystalline silicon solar cells and amorphous silicon solar cells.

2. Battery

The function of the battery is mainly to store the electrical energy generated by the solar cell and can supply power to the load at any time. The basic requirements of the solar photovoltaic power generation system for the battery are: low self-discharge rate, long service life, high charging efficiency, strong deep discharge capacity, wide operating temperature range, low maintenance or maintenance-free and low cost. At present, the main maintenance-free lead-acid battery used in the photovoltaic system is in small and micro systems. Mirror hydrogen battery, nickel-cadmium battery, lithium battery or supercapacitor can also be used. When there is a large capacity of electric energy storage, multiple batteries need to be connected in series and parallel to form a battery pack.

3. Photovoltaic controller

The function of the solar photovoltaic controller is to control the working state of the entire system. Its main functions include protection against battery overcharge, protection against battery overdischarge, system short circuit electronic protection, system polarity reverse connection protection, nighttime anti-reverse charging protection, etc. In places with large temperature differences, the controller also has the function of temperature compensation. In addition, the controller also has working modes such as light-controlled switch and time-controlled switch, as well as display functions for various working states such as charging status and battery power. Photovoltaic controllers are generally divided into low-power, medium-power, high-power and wind-solar hybrid controllers.

4. AC inverter

AC inverter is a device that converts the DC power output by solar cell modules or batteries into AC power to supply to the power grid or AC load. Inverters can be divided into independent inverters and grid-connected inverters according to different operating modes. Independent inverters are used for independently operated solar power generation systems to power independent loads. Grid-connected inverters are used for grid-connected solar power generation systems.