What is the structure of a photovoltaic inverter? How long is the service life of a photovoltaic inverter?

Photovoltaic inverter, as a DC-AC conversion power adjustment device, is divided into two parts: boost circuit and inverter bridge circuit, mainly composed of semiconductor devices. The main semiconductor devices are as follows:
1. Current sensor: It is required to have high precision, fast response, low-temperature resistance, high-temperature resistance, etc. Different current sensors are used for different powers, and Hall current sensors are generally used for current sampling;
2. Current Transformer: Wide current range, BRS series current transformer is generally used;
3. Reactor.
When encountering the shutdown of the photovoltaic inverter, the shutdown operation on the LCD panel is required first, and then the photovoltaic inverter will be controlled to stop. After the switch on the back of the inverter, the photovoltaic inverter will be directly connected to the AC cabinet, and then the two direct input circuit breakers in the photovoltaic inverter will be directly rotated to the closed state, and then disconnected. In the previous opening, if the inverter is directly set to an external power supply scale, it is also possible to cut off the external power supply inside, and then the circuit breaker will be withdrawn to operate.

After confirming that the PV inverter is completely disconnected from the AC side, you will use your own multimeter to check the side of the AC inside, that is, you will make sure that you have no points, and then make sure that it will not be reconnected to the power supply, and then It can be directly connected to the bottom line, observe whether there is a hanging place for the photovoltaic inverter, observe whether there is deformation, check whether there is humidity above the environment, and check the filter when all air inlets are Is it normal.
To start the photovoltaic inverter, first, remove the ground wire, then close the transformer on the box and then open the hall on the side, then open the Xi'an road of the AC output of the photovoltaic inverter directly to the switch stage, and then close a bus box until the start, and then use the closed DC cabinet until the real input starts, then turn both DCs to the ON stage, wait for about a minute, and turn on the other things in turn, the photovoltaic The inverter is ready to start.
The life of photovoltaic modules is 25 years, and whether the life of the inverter can reach 25 years depends on the equipment maintenance method. The string inverter generally adopts the whole machine replacement and maintenance method, and the quality requirements for power station maintainers are compared. Low, the life of the whole machine depends on the component with the shortest life. The centralized inverter generally adopts the module maintenance method. The whole machine is divided into several modules. The maintenance engineer first detects which module is faulty, and then replaces the faulty module. The life of the whole mechanism depends on the life of the most valuable components. In distributed photovoltaic power plants, string inverters are mainly used. The following mainly takes string inverters as an example.

The short life of the photovoltaic inverter
The photovoltaic inverter is composed of structural parts, circuit boards, power switch tubes, capacitors, liquid crystal displays, and fans.
1. Electrolytic capacitors are indeed one of the most vulnerable components of inverters. There is an electrolyte in the electrolytic capacitor. Over time, the electrolyte may evaporate and dry, resulting in an increase in the equivalent series impedance of the electrolytic capacitor. Under the same current, higher ESR will cause the capacitor to heat up, thus further aggravating the evaporation of the electrolyte, forming a vicious cycle that eventually leads to device failure. The best capacitor on the photovoltaic inverter is the NCC capacitor, and its capacitor specification clearly states: "Please note that the calculated result is not a guaranteed value. When designing the life of the equipment, please review the service life margin. Also, if the estimated life of capacitors exceeds 15 years, please use 15 years as the upper limit.”
2. In addition to electrolytic capacitors, there are many components with a lifespan of fewer than 25 years, such as liquid crystal displays, including PVC material connectors, cables, terminals, etc. Thermal grease can timely remove the heat generated by electronic components. Conducted out, if there is no thermal grease, the heat generated by the vital components cannot be conducted in time, then the components will be quickly aged and damaged, but the life of thermal grease is generally about 10 years.