A photovoltaic (PV) power generation system mainly consists of PV modules, a controller, an inverter, batteries, and other accessories (grid-connected systems do not require batteries). Based on whether they rely on the public power grid, they are divided into off-grid and grid-connected systems. Off-grid systems operate independently and do not depend on the power grid. Off-grid PV systems are equipped with batteries that provide energy storage, ensuring stable system power and supplying electricity to the load when the PV system does not generate power at night or on cloudy or rainy days.
Regardless of the form, the working principle is the same: photovoltaic modules convert light energy into direct current (DC), and the DC is converted into alternating current (AC) by the inverter, ultimately enabling the use of electricity and access to the internet.
1. Photovoltaic modules
Photovoltaic modules are the core component of a photovoltaic system. They consist of a series of photovoltaic panels made of semiconductor materials that convert sunlight into electrical energy. Photovoltaic modules are typically installed on rooftops or open ground to maximize the amount of sunlight they receive.
2. Inverter
Inverters are a crucial component of photovoltaic (PV) systems, converting the direct current (DC) output from PV modules into alternating current (AC). This AC power can be easily connected to the grid to supply electricity for homes or industries. Inverters are characterized by high efficiency, stability, and reliability, making them one of the key pieces of equipment in a PV system.
3. Photovoltaic combiner box
The function of a photovoltaic combiner box is to collect the current output from photovoltaic modules and aggregate it. A photovoltaic combiner box typically contains multiple terminals for connecting the photovoltaic modules and the inverter. It is waterproof, dustproof, and corrosion-resistant, allowing it to operate stably in harsh environments.
4. Controller
The controller is the brain of a photovoltaic system, responsible for monitoring and controlling the entire system. It monitors parameters such as the output power of the photovoltaic modules, system voltage, and current in real time, and adjusts the system accordingly to ensure stable operation. The controller also has protection functions to prevent system overload, short circuits, and other abnormal conditions.
5. Energy storage equipment
Energy storage devices are used to store electrical energy in photovoltaic systems. Common energy storage devices include batteries and supercapacitors. Batteries can provide energy to the system under low light conditions, ensuring the normal operation of the system; supercapacitors have the characteristics of rapid charging and discharging, which can be used to smooth the system's output current and improve the system's stability.
6. Cables and connectors
Cables and connectors are components used to transmit electrical energy in photovoltaic systems. Cables need to have excellent insulation and weather resistance to ensure efficient power transmission; connectors need to have good contact performance and stability to ensure the safety and reliability of the system.
A typical photovoltaic (PV) power generation system consists of modules, inverters, grid-connected boxes, support structures, and AC/DC cables. The modules are the core component of the system; they form an array to convert solar energy into electrical energy, thus generating PV power. The diagram below illustrates the process of a PV power station from power generation to grid connection. The module array is fixed to the roof using a support structure. The DC current generated by the array is transmitted through DC cables, converted to AC by the inverter, and then fed into the grid via the grid-connected box.
photovoltaic modules
As the core component of a photovoltaic power generation system, the important parameters of the module include power, voltage, current, length and width dimensions, and weight. Among them, the voltage and current of the module determine the type of inverter, and the length and width dimensions determine the number of modules that can be installed on a roof.
As can be seen, sunlight passes through the glass backsheet of the module, the N-type semiconductor inside the module moves towards the negative electrode, the P-type semiconductor moves towards the positive electrode, and current flows through after the external load forms a circuit.
Photovoltaic inverter
Inverters convert the direct current output from solar panels into alternating current (AC) that can be used by general electrical appliances. They also maximize the performance of solar cells and provide system fault protection. The selection of inverters for photovoltaic power plants must consider parameters such as the installed capacity of the power plant, the voltage and current of the solar panels, and the number of panels.
Photovoltaic grid-connected box
The grid-connected box mainly consists of disconnectors, circuit breakers and related control components. As the end of the photovoltaic power generation system, it connects the power grid and the power generation system, protects and measures the total amount of photovoltaic power generation, facilitates fault repair and management, and improves the safety and economic efficiency of the power generation system.
Photovoltaic support
As an important component of photovoltaic power generation systems, photovoltaic brackets mainly serve to connect the components to the roof. Taking a flat roof as an example, under the premise of ensuring the power station's load-bearing capacity and wind resistance are safe, the power station can be installed at an angle to maximize power generation and increase the owner's income.
TRW original guide rails feature a U-shaped cross-section design, providing compressive and bending resistance to meet the load-bearing requirements of power plants. Made of zinc-aluminum-magnesium galvanized steel, they have the advantage of self-repairing when rusted, making them not only corrosion-resistant but also aesthetically pleasing.
1. The main components of an independent photovoltaic power generation system are: controller, battery pack, solar cell modules, and inverter.
2. The main components of a grid-connected photovoltaic power generation system are: inverter, solar cell array, and battery array.
3. The main components of a distributed photovoltaic power generation system are: photovoltaic cell modules, DC combiner boxes, grid-connected inverters, AC distribution cabinets, photovoltaic array supports, DC distribution cabinets, and other equipment.
Summarize:
For photovoltaic power plants to have an operational lifespan of over 25 years, rigorous quality control is essential at every stage of construction. Trina Smart Distributed, a leading brand of distributed photovoltaics in China, consistently adheres to original equipment standards. Through systematic operation and management, standardized original equipment systems, and 24/7 remote monitoring and maintenance, it forms a closed-loop quality control system to ensure stable and continuous operation throughout the entire power generation lifespan. This creates tangible economic benefits for users, aligns with national strategies, and supports county-wide development, driving high-quality development of the industry through concrete actions!
