Inverter Q&A

　　As the global pace of reducing carbon emissions is getting faster and faster, the development of clean energy has also entered a fast track. Among them, photovoltaic power generation is known as the most suitable clean energy at this stage, and its supporting inverters, lithium battery energy storage systems, etc. are constantly updated. Although SES Power is mainly engaged in the production of customized lithium batteries, we have many projects that need to be used with various inverters. In order to provide better services to customers, we choose inverters as accessories. The most frequently asked questions by users are answered here.

　　Q: The temperature of the back of the inverter is a little high when it is working. Is this normal?

　　A: This is normal, because the whole inverter dissipates heat through the heat sink on the back, and the inverter can only operate normally if the heat dissipation is normal. However, the normal operating ambient temperature is generally within 60 degrees. If it is too high, the inverter will run with reduced load. During installation, it is recommended to install the inverter in a cool and ventilated place to avoid exposure to the sun.

　　Q Why is the active power of photovoltaics preferentially consumed?

　　A: Photovoltaic power generation is a kind of power source, it can output electric energy, and can only output electric energy, and the grid is a special kind of power source, it can not only provide electric energy to the load, but also can receive electric energy as a load. According to the principle that current flows from places with high voltage to places with low voltage, when photovoltaic power is generated, the voltage of the grid-connected inverter is always slightly higher than the grid voltage from the perspective of the load, so the load preferentially uses photovoltaic power generation, only When the photovoltaic power is less than the load power, the voltage of the grid connection point will drop, and the grid will supply power to the load.

　　Q: Why does the photovoltaic power station installed in my home fail to achieve the ideal power generation?

　　A: The amount of photovoltaic power generation changes dynamically according to objective conditions. In addition to the loss of the photovoltaic system itself, the intensity of solar radiation, the inclination angle of photovoltaic modules, dust, snow, shadows, etc. block the light reaching the modules and exceed the power of the cells. The standard operating temperature (25℃) and other reasons will reduce the power generation. Therefore, it is recommended to select a suitable inclination angle and regularly clean the photovoltaic panels during installation.

　　Q: Will adding a free compensation device to improve the power factor reduce the power generation of the inverter?

　　A: Adding reactive power compensation device to improve the power factor will not affect the power generation of the inverter. Using the inverter itself to do limited reactive power compensation, the power factor is above 0.9, and it will not affect the power generation of the inverter; However, if the power factor of the inverter is set lower than 0.9, it will affect the active output of the inverter and thus the power generation.

　　Q: The inverter stops and the red light is on. The display screen shows that the grid voltage is too high/too low, the grid frequency is too high/too low, the grid is missing, and the corresponding fault code is displayed. What is the solution?

　　A: The inverter reports over-under-voltage faults and over-under-frequency faults are mostly due to the problem of the power grid itself, not the inverter. The inverter itself can properly relax the voltage and frequency ranges under the conditions of safety regulations.

　　In addition, remind users again that there are many types of secondary batteries that can be used with photovoltaic power generation, such as nickel-metal hydride batteries, lead-acid batteries, lithium batteries, etc. SES Power recommends that you use a lithium iron phosphate battery because of its long life, good safety performance, and light weight. For example, we use 12V100Ah, 24V100Ah, 36V100Ah, 48V100Ah, 60V100Ah, 3KW, 5KW home energy storage systems, rack-mounted energy storage systems and other products of square aluminum-shell lithium iron phosphate batteries from EVE, CATL, and BYD, which are very popular with customers. Here is an application example of replacing lead-acid batteries with lithium iron phosphate batteries. 12V/100Ah (1280Wh) lead-acid battery, its weight is 26kg, the number of charging times is about 300 times, and the use time is about 2 years. If the lithium iron phosphate power battery is used, the same 320Wh energy (4 100Ah batteries connected in series) is used, the weight is about 9kg, the number of charging times can reach 4000 times, and the service life can reach 5 to 8 years. If it is used in conjunction with photovoltaic power generation, the overall economic effect must be that lithium iron phosphate batteries are far better than lead-acid batteries.